switch to linux-only setup

.gitignore

@@ -0,0 +1,4 @@
+__pycache__
+build
+cmake-build-*
+

CMakeLists.txt

@@ -0,0 +1,42 @@
+cmake_minimum_required(VERSION 3.22)
+
+project(kge)
+
+find_package(SDL2 REQUIRED)
+find_package(OpenGL REQUIRED)
+
+add_compile_options("-Wall" "-Wextra" "-Werror")
+add_definitions(-DIMGUI_ENABLE_FREETYPE)
+
+add_library(imgui STATIC
+        # Main Imgui files
+        ext/imgui/imgui.cpp
+        ext/imgui/imgui.h
+        ext/imgui/imgui_draw.cpp
+        ext/imgui/imgui_tables.cpp
+        ext/imgui/imgui_widgets.cpp
+        ext/imgui/imgui_demo.cpp
+
+        ext/imgui/backends/imgui_impl_sdl2.cpp
+        ext/imgui/backends/imgui_impl_sdl2.h
+        ext/imgui/backends/imgui_impl_opengl3.cpp
+        ext/imgui/backends/imgui_impl_opengl3.h)
+add_library(imgui::imgui ALIAS imgui)
+target_link_libraries(imgui
+    PUBLIC
+    OpenGL::GL
+    $<TARGET_NAME_IF_EXISTS:SDL2::SDL2main>
+    $<IF:$<TARGET_EXISTS:SDL2::SDL2>,SDL2::SDL2,SDL2::SDL2-static>
+)
+target_include_directories(imgui PUBLIC
+	ext/imgui/
+	ext/imgui/backends/
+)
+
+include_directories(ext/)
+
+add_executable(kge
+	kge.cc
+)
+target_link_libraries(kge imgui)
+

ext/imgui/.editorconfig

@@ -0,0 +1,28 @@
+# See http://editorconfig.org to read about the EditorConfig format.
+# - In theory automatically supported by VS2017+ and most common IDE or text editors.
+# - In practice VS2019-VS2022 stills don't trim trailing whitespaces correctly :(
+#   - Suggest installing this to trim whitespaces:
+#      GitHub https://github.com/madskristensen/TrailingWhitespace
+#      VS2019 https://marketplace.visualstudio.com/items?itemName=MadsKristensen.TrailingWhitespaceVisualizer
+#      VS2022 https://marketplace.visualstudio.com/items?itemName=MadsKristensen.TrailingWhitespace64
+#     (in spite of its name doesn't only visualize but also trims)
+#   - Alternative for older VS2010 to VS2015: https://marketplace.visualstudio.com/items?itemName=EditorConfigTeam.EditorConfig
+
+# top-most EditorConfig file
+root = true
+
+# Default settings:
+# Use 4 spaces as indentation
+[*]
+indent_style = space
+indent_size = 4
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[imstb_*]
+indent_size = 3
+trim_trailing_whitespace = false
+
+[Makefile]
+indent_style = tab
+indent_size = 4

ext/imgui/.gitattributes

@@ -0,0 +1,30 @@
+* text=auto
+
+*.c text
+*.cpp text
+*.h text
+*.m text
+*.mm text
+*.md text
+*.txt text
+*.html text
+*.bat text
+*.frag text
+*.vert text
+*.mkb text
+*.icf text
+
+*.sln text eol=crlf
+*.vcxproj text eol=crlf
+*.vcxproj.filters text eol=crlf
+*.natvis text eol=crlf
+
+Makefile text eol=lf
+*.sh text eol=lf
+*.pbxproj text eol=lf
+*.storyboard text eol=lf
+*.plist text eol=lf
+
+*.png binary
+*.ttf binary
+*.lib binary

ext/imgui/.github/FUNDING.yml

@@ -0,0 +1 @@
+custom: ['https://github.com/ocornut/imgui/wiki/Sponsors']

ext/imgui/.github/issue_template.md

@@ -0,0 +1,46 @@
+(Click "Preview" above ^ to turn URL into clickable links)
+
+1. FOR FIRST-TIME USERS PROBLEMS COMPILING/LINKING/RUNNING or LOADING FONTS,  please use [GitHub Discussions](https://github.com/ocornut/imgui/discussions). EVERYTHING ELSE CAN BE POSTED HERE!
+
+2. PLEASE CAREFULLY READ: [FAQ](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md)
+
+3. PLEASE CAREFULLY READ: [Contributing Guidelines](https://github.com/ocornut/imgui/blob/master/docs/CONTRIBUTING.md)
+
+4. PLEASE MAKE SURE that you have: read the FAQ; explored the contents of `ShowDemoWindow()` including the Examples menu; searched among Issues; used your IDE to search for keywords in all sources and text files; and read the links above.
+
+5. Be mindful that messages are being sent to the e-mail box of "Watching" users. Try to proof-read your messages before sending them. Edits are not seen by those users.
+
+6. Delete points 1-6 and PLEASE FILL THE TEMPLATE BELOW before submitting your issue.
+
+Thank you!
+
+----
+
+_(you may also go to Demo>About Window, and click "Config/Build Information" to obtain a bunch of detailed information that you can paste here)_
+
+**Version/Branch of Dear ImGui:**
+
+Version: XXX
+Branch: XXX _(master/viewport/docking/etc.)_
+
+**Back-end/Renderer/Compiler/OS**
+
+Back-ends: imgui_impl_XXX.cpp + imgui_impl_XXX.cpp _(or specify if using a custom engine/back-end)_
+Compiler: XXX _(if the question is related to building or platform specific features)_
+Operating System: XXX
+
+**My Issue/Question:**
+
+XXX _(please provide as much context as possible)_
+
+**Screenshots/Video**
+
+XXX _(you can drag files here)_
+
+**Standalone, minimal, complete and verifiable example:** _(see https://github.com/ocornut/imgui/issues/2261)_
+```
+// Here's some code anyone can copy and paste to reproduce your issue
+ImGui::Begin("Example Bug");
+MoreCodeToExplainMyIssue();
+ImGui::End();
+```

ext/imgui/.github/pull_request_template.md

@@ -0,0 +1,6 @@
+(Click "Preview" to turn any http URL into a clickable link)
+
+1. PLEASE CAREFULLY READ: [Contributing Guidelines](https://github.com/ocornut/imgui/blob/master/docs/CONTRIBUTING.md)
+
+2. Clear this template before submitting your PR.
+

ext/imgui/.github/workflows/build.yml

@@ -0,0 +1,507 @@
+name: build
+
+on:
+  push:
+  pull_request:
+  workflow_run:
+    # Use a workflow as a trigger of scheduled builds. Forked repositories can disable scheduled builds by disabling
+    # "scheduled" workflow, while maintaining ability to perform local CI builds.
+    workflows:
+      - scheduled
+    branches:
+      - master
+      - docking
+    types:
+      - requested
+
+jobs:
+  Windows:
+    runs-on: windows-2019
+    env:
+      VS_PATH: C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\
+      MSBUILD_PATH: C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin\
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Install Dependencies
+        shell: powershell
+        run: |
+          Invoke-WebRequest -Uri "https://www.libsdl.org/release/SDL2-devel-2.26.3-VC.zip" -OutFile "SDL2-devel-2.26.3-VC.zip"
+          Expand-Archive -Path SDL2-devel-2.26.3-VC.zip
+          echo "SDL2_DIR=$(pwd)\SDL2-devel-2.26.3-VC\SDL2-2.26.3\" >>${env:GITHUB_ENV}
+
+          Invoke-WebRequest -Uri "https://github.com/ocornut/imgui/files/3789205/vulkan-sdk-1.1.121.2.zip" -OutFile vulkan-sdk-1.1.121.2.zip
+          Expand-Archive -Path vulkan-sdk-1.1.121.2.zip
+          echo "VULKAN_SDK=$(pwd)\vulkan-sdk-1.1.121.2\" >>${env:GITHUB_ENV}
+
+      - name: Fix Projects
+        shell: powershell
+        run: |
+          # CI workers do not supporter older Visual Studio versions. Fix projects to target newer available version.
+          gci -recurse -filter "*.vcxproj" | ForEach-Object {
+            (Get-Content $_.FullName) -Replace "<PlatformToolset>v\d{3}</PlatformToolset>","<PlatformToolset>v142</PlatformToolset>" | Set-Content -Path $_.FullName
+            (Get-Content $_.FullName) -Replace "<WindowsTargetPlatformVersion>[\d\.]+</WindowsTargetPlatformVersion>","<WindowsTargetPlatformVersion>10.0.18362.0</WindowsTargetPlatformVersion>" | Set-Content -Path $_.FullName
+          }
+
+      # Not using matrix here because it would inflate job count too much. Check out and setup is done for every job and that makes build times way too long.
+      - name: Build example_null (extra warnings, mingw 64-bit)
+        run: mingw32-make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+      - name: Build example_null (mingw 64-bit, as DLL)
+        shell: bash
+        run: |
+          echo '#ifdef _EXPORT'                                  >  example_single_file.cpp
+          echo '#  define IMGUI_API __declspec(dllexport)'       >> example_single_file.cpp
+          echo '#else'                                           >> example_single_file.cpp
+          echo '#  define IMGUI_API __declspec(dllimport)'       >> example_single_file.cpp
+          echo '#endif'                                          >> example_single_file.cpp
+          echo '#define IMGUI_IMPLEMENTATION'                    >> example_single_file.cpp
+          echo '#include "misc/single_file/imgui_single_file.h"' >> example_single_file.cpp
+          g++ -I. -Wall -Wformat -D_EXPORT -shared -o libimgui.dll -Wl,--out-implib,libimgui.a example_single_file.cpp -limm32
+          g++ -I. -Wall -Wformat -o example_null.exe examples/example_null/main.cpp -L. -limgui
+          rm -f example_null.exe libimgui.* example_single_file.*
+
+      - name: Build example_null (extra warnings, msvc 64-bit)
+        shell: cmd
+        run: |
+          cd examples\example_null
+          call "%VS_PATH%\VC\Auxiliary\Build\vcvars64.bat"
+          .\build_win32.bat /W4
+
+      - name: Build example_null (single file build)
+        shell: bash
+        run: |
+          cat > example_single_file.cpp <<'EOF'
+
+          #define IMGUI_IMPLEMENTATION
+          #include "misc/single_file/imgui_single_file.h"
+          #include "examples/example_null/main.cpp"
+
+          EOF
+          g++ -I. -Wall -Wformat -o example_single_file.exe example_single_file.cpp -limm32
+
+      - name: Build example_null (with IMGUI_DISABLE_WIN32_FUNCTIONS)
+        shell: bash
+        run: |
+          cat > example_single_file.cpp <<'EOF'
+
+          #define IMGUI_DISABLE_WIN32_FUNCTIONS
+          #define IMGUI_IMPLEMENTATION
+          #include "misc/single_file/imgui_single_file.h"
+          #include "examples/example_null/main.cpp"
+
+          EOF
+          g++ -I. -Wall -Wformat -o example_single_file.exe example_single_file.cpp -limm32
+
+      - name: Build example_null (as DLL)
+        shell: cmd
+        run: |
+          call "%VS_PATH%\VC\Auxiliary\Build\vcvars64.bat"
+
+          echo #ifdef _EXPORT                                  >  example_single_file.cpp
+          echo #  define IMGUI_API __declspec(dllexport)       >> example_single_file.cpp
+          echo #else                                           >> example_single_file.cpp
+          echo #  define IMGUI_API __declspec(dllimport)       >> example_single_file.cpp
+          echo #endif                                          >> example_single_file.cpp
+          echo #define IMGUI_IMPLEMENTATION                    >> example_single_file.cpp
+          echo #include "misc/single_file/imgui_single_file.h" >> example_single_file.cpp
+
+          cl.exe /D_USRDLL /D_WINDLL /D_EXPORT /I. example_single_file.cpp /LD /FeImGui.dll /link
+          cl.exe /I. ImGui.lib /Feexample_null.exe examples/example_null/main.cpp
+
+      - name: Build Win32 example_glfw_opengl2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_opengl2/example_glfw_opengl2.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+
+      - name: Build Win32 example_glfw_opengl3
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_opengl3/example_glfw_opengl3.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build Win32 example_glfw_vulkan
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build Win32 example_sdl2_vulkan
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_vulkan/example_sdl2_vulkan.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build Win32 example_sdl2_opengl2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_opengl2/example_sdl2_opengl2.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build Win32 example_sdl2_opengl3
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_opengl3/example_sdl2_opengl3.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+
+      - name: Build Win32 example_sdl2_directx11
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_directx11/example_sdl2_directx11.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build Win32 example_win32_directx9
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx9/example_win32_directx9.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+
+      - name: Build Win32 example_win32_directx10
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx10/example_win32_directx10.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+
+      - name: Build Win32 example_win32_directx11
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx11/example_win32_directx11.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_glfw_opengl2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_opengl2/example_glfw_opengl2.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_glfw_opengl3
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_opengl3/example_glfw_opengl3.vcxproj /p:Platform=x64 /p:Configuration=Release'
+
+      - name: Build x64 example_glfw_vulkan
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj /p:Platform=x64 /p:Configuration=Release'
+
+      - name: Build x64 example_sdl2_vulkan
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_vulkan/example_sdl2_vulkan.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_sdl2_opengl2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_opengl2/example_sdl2_opengl2.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_sdl2_opengl3
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_opengl3/example_sdl2_opengl3.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_sdl2_directx11
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_directx11/example_sdl2_directx11.vcxproj /p:Platform=x64 /p:Configuration=Release'
+
+      - name: Build x64 example_win32_directx9
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx9/example_win32_directx9.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_win32_directx10
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx10/example_win32_directx10.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_win32_directx11
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx11/example_win32_directx11.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
+      - name: Build x64 example_win32_directx12
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx12/example_win32_directx12.vcxproj /p:Platform=x64 /p:Configuration=Release'
+
+  Linux:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Install Dependencies
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y libglfw3-dev libsdl2-dev gcc-multilib g++-multilib libfreetype6-dev libvulkan-dev
+
+    - name: Build example_null (extra warnings, gcc 32-bit)
+      run: |
+        make -C examples/example_null clean
+        CXXFLAGS="$CXXFLAGS -m32 -Werror" make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+    - name: Build example_null (extra warnings, gcc 64-bit)
+      run: |
+        make -C examples/example_null clean
+        CXXFLAGS="$CXXFLAGS -m64 -Werror" make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+    - name: Build example_null (extra warnings, clang 32-bit)
+      run: |
+        make -C examples/example_null clean
+        CXXFLAGS="$CXXFLAGS -m32 -Werror" CXX=clang++ make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+    - name: Build example_null (extra warnings, clang 64-bit)
+      run: |
+        make -C examples/example_null clean
+        CXXFLAGS="$CXXFLAGS -m64 -Werror" CXX=clang++ make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+    - name: Build example_null (extra warnings, empty IM_ASSERT)
+      run: |
+          cat > example_single_file.cpp <<'EOF'
+
+          #define IM_ASSERT(x)
+          #define IMGUI_IMPLEMENTATION
+          #include "misc/single_file/imgui_single_file.h"
+          #include "examples/example_null/main.cpp"
+
+          EOF
+          g++ -I. -std=c++11 -Wall -Wformat -Wextra -Werror -Wno-zero-as-null-pointer-constant -Wno-double-promotion -Wno-variadic-macros -Wno-empty-body -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (freetype)
+      run: |
+        make -C examples/example_null clean
+        make -C examples/example_null WITH_FREETYPE=1
+
+    - name: Build example_null (single file build)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with ImWchar32)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_USE_WCHAR32
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with large ImDrawIdx + pointer ImTextureID)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define ImTextureID void*
+        #define ImDrawIdx unsigned int
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IMGUI_DISABLE_OBSOLETE_FUNCTIONS)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IMGUI_DISABLE_OBSOLETE_KEYIO)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_DISABLE_OBSOLETE_KEYIO
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IMGUI_DISABLE_DEMO_WINDOWS and IMGUI_DISABLE_DEBUG_TOOLS)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_DISABLE_DEMO_WINDOWS
+        #define IMGUI_DISABLE_DEBUG_TOOLS
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IMGUI_DISABLE_FILE_FUNCTIONS)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_DISABLE_FILE_FUNCTIONS
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IMGUI_USE_BGRA_PACKED_COLOR)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_USE_BGRA_PACKED_COLOR
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (with IM_VEC2_CLASS_EXTRA and IM_VEC4_CLASS_EXTRA)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        struct MyVec2 { float x; float y; MyVec2(float x, float y) : x(x), y(y) { } };
+        struct MyVec4 { float x; float y; float z; float w;
+        MyVec4(float x, float y, float z, float w) : x(x), y(y), z(z), w(w) { } };
+        #define IM_VEC2_CLASS_EXTRA                                             \
+                ImVec2(const MyVec2& f) { x = f.x; y = f.y; }                   \
+                operator MyVec2() const { return MyVec2(x, y); }
+        #define IM_VEC4_CLASS_EXTRA                                             \
+                ImVec4(const MyVec4& f) { x = f.x; y = f.y; z = f.z; w = f.w; } \
+                operator MyVec4() const { return MyVec4(x, y, z, w); }
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (without c++ runtime, Clang)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #define IMGUI_DISABLE_DEMO_WINDOWS
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        clang++ -I. -std=c++11 -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
+
+    - name: Build example_glfw_opengl2
+      run: make -C examples/example_glfw_opengl2
+
+    - name: Build example_glfw_opengl3
+      run: make -C examples/example_glfw_opengl3
+      if: github.event_name == 'workflow_run'
+
+    - name: Build example_sdl2_opengl2
+      run: make -C examples/example_sdl2_opengl2
+      if: github.event_name == 'workflow_run'
+
+    - name: Build example_sdl2_opengl3
+      run: make -C examples/example_sdl2_opengl3
+
+    - name: Build with IMGUI_IMPL_VULKAN_NO_PROTOTYPES
+      run: g++ -c -I. -std=c++11 -DIMGUI_IMPL_VULKAN_NO_PROTOTYPES=1 backends/imgui_impl_vulkan.cpp
+
+  MacOS:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Install Dependencies
+      run: |
+        brew install glfw3 sdl2
+
+    - name: Build example_null (extra warnings, clang 64-bit)
+      run: make -C examples/example_null WITH_EXTRA_WARNINGS=1
+
+    - name: Build example_null (single file build)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        clang++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
+
+    - name: Build example_null (without c++ runtime)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        clang++ -I. -std=c++11 -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
+
+    - name: Build example_glfw_opengl2
+      run: make -C examples/example_glfw_opengl2
+
+    - name: Build example_glfw_opengl3
+      run: make -C examples/example_glfw_opengl3
+      if: github.event_name == 'workflow_run'
+
+    - name: Build example_glfw_metal
+      run: make -C examples/example_glfw_metal
+
+    - name: Build example_sdl2_metal
+      run: make -C examples/example_sdl2_metal
+
+    - name: Build example_sdl2_opengl2
+      run: make -C examples/example_sdl2_opengl2
+      if: github.event_name == 'workflow_run'
+
+    - name: Build example_sdl2_opengl3
+      run: make -C examples/example_sdl2_opengl3
+
+    - name: Build example_apple_metal
+      run: xcodebuild -project examples/example_apple_metal/example_apple_metal.xcodeproj -target example_apple_metal_macos
+
+    - name: Build example_apple_opengl2
+      run: xcodebuild -project examples/example_apple_opengl2/example_apple_opengl2.xcodeproj -target example_osx_opengl2
+
+  iOS:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Build example_apple_metal
+      run: |
+        # Code signing is required, but we disable it because it is irrelevant for CI builds.
+        xcodebuild -project examples/example_apple_metal/example_apple_metal.xcodeproj -target example_apple_metal_ios CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGNING_ALLOWED=NO
+
+  Emscripten:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Install Dependencies
+      run: |
+        wget -q https://github.com/emscripten-core/emsdk/archive/master.tar.gz
+        tar -xvf master.tar.gz
+        emsdk-master/emsdk update
+        emsdk-master/emsdk install latest
+        emsdk-master/emsdk activate latest
+
+    - name: Build example_sdl2_opengl3 with Emscripten
+      run: |
+        pushd emsdk-master
+        source ./emsdk_env.sh
+        popd
+        make -C examples/example_sdl2_opengl3 -f Makefile.emscripten
+
+    - name: Build example_emscripten_wgpu
+      run: |
+        pushd emsdk-master
+        source ./emsdk_env.sh
+        popd
+        make -C examples/example_emscripten_wgpu
+
+  Android:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Build example_android_opengl3
+      run: |
+        cd examples/example_android_opengl3/android
+        gradle assembleDebug --stacktrace

ext/imgui/.github/workflows/scheduled.yml

@@ -0,0 +1,15 @@
+#
+# This is a dummy workflow used to trigger scheduled builds. Forked repositories most likely should disable this
+# workflow to avoid daily builds of inactive repositories.
+#
+name: scheduled
+
+on:
+  schedule:
+    - cron:  '0 9 * * *'
+
+jobs:
+  scheduled:
+    runs-on: ubuntu-latest
+    steps:
+      - run: exit 0

ext/imgui/.github/workflows/static-analysis.yml

@@ -0,0 +1,46 @@
+name: static-analysis
+
+on:
+  workflow_run:
+    # Perform static analysis together with build workflow. Build triggers of "build" workflow do not need to be repeated here.
+    workflows:
+      - build
+    types:
+      - requested
+
+jobs:
+  PVS-Studio:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 1
+
+      - name: Install Dependencies
+        env:
+          # The Secret variable setup in GitHub must be in format: "name_or_email key", on a single line
+          PVS_STUDIO_LICENSE: ${{ secrets.PVS_STUDIO_LICENSE }}
+        run: |
+          if [[ "$PVS_STUDIO_LICENSE" != "" ]];
+          then
+            wget -q https://files.viva64.com/etc/pubkey.txt
+            sudo apt-key add pubkey.txt
+            sudo wget -O /etc/apt/sources.list.d/viva64.list https://files.viva64.com/etc/viva64.list
+            sudo apt-get update
+            sudo apt-get install -y pvs-studio
+            pvs-studio-analyzer credentials -o pvs-studio.lic $PVS_STUDIO_LICENSE
+          fi
+
+      - name: PVS-Studio static analysis
+        run: |
+          if [[ ! -f pvs-studio.lic ]];
+          then
+            echo "PVS Studio license is missing. No analysis will be performed."
+            echo "If you have a PVS Studio license please create a project secret named PVS_STUDIO_LICENSE with your license."
+            echo "You may use a free license. More information at https://www.viva64.com/en/b/0457/"
+            exit 0
+          fi
+          cd examples/example_null
+          pvs-studio-analyzer trace -- make WITH_EXTRA_WARNINGS=1
+          pvs-studio-analyzer analyze -e ../../imstb_rectpack.h -e ../../imstb_textedit.h -e ../../imstb_truetype.h -l ../../pvs-studio.lic -o pvs-studio.log
+          plog-converter -a 'GA:1,2;OP:1' -d V1071 -t errorfile -w pvs-studio.log

ext/imgui/.gitignore

@@ -0,0 +1,59 @@
+## OSX artifacts
+.DS_Store
+
+## Dear ImGui artifacts
+imgui.ini
+
+## General build artifacts
+*.o
+*.obj
+*.exe
+examples/*/Debug/*
+examples/*/Release/*
+examples/*/x64/*
+
+## Visual Studio artifacts
+.vs
+ipch
+*.opensdf
+*.log
+*.pdb
+*.ilk
+*.user
+*.sdf
+*.suo
+*.VC.db
+*.VC.VC.opendb
+
+## Getting files created in JSON/Schemas/Catalog/ from a VS2022 update
+JSON/
+
+## Commonly used CMake directories
+build*/
+
+## Xcode artifacts
+project.xcworkspace
+xcuserdata
+
+## Emscripten artifacts
+examples/*.o.tmp
+examples/*.out.js
+examples/*.out.wasm
+examples/example_glfw_opengl3/web/*
+examples/example_sdl2_opengl3/web/*
+examples/example_emscripten_wgpu/web/*
+
+## JetBrains IDE artifacts
+.idea
+cmake-build-*
+
+## Unix executables from our example Makefiles
+examples/example_glfw_metal/example_glfw_metal
+examples/example_glfw_opengl2/example_glfw_opengl2
+examples/example_glfw_opengl3/example_glfw_opengl3
+examples/example_glut_opengl2/example_glut_opengl2
+examples/example_null/example_null
+examples/example_sdl2_metal/example_sdl2_metal
+examples/example_sdl2_opengl2/example_sdl2_opengl2
+examples/example_sdl2_opengl3/example_sdl2_opengl3
+examples/example_sdl2_sdlrenderer/example_sdl2_sdlrenderer

ext/imgui/LICENSE.txt

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014-2023 Omar Cornut
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

ext/imgui/backends/imgui_impl_allegro5.cpp

@@ -0,0 +1,613 @@
+// dear imgui: Renderer + Platform Backend for Allegro 5
+// (Info: Allegro 5 is a cross-platform general purpose library for handling windows, inputs, graphics, etc.)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ALLEGRO_BITMAP*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Clipboard support (from Allegro 5.1.12)
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Issues:
+//  [ ] Renderer: The renderer is suboptimal as we need to convert vertices manually.
+//  [ ] Platform: Missing gamepad support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-11-30: Renderer: Restoring using al_draw_indexed_prim() when Allegro version is >= 5.2.5.
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-17: Inputs: always calling io.AddKeyModsEvent() next and before key event (not in NewFrame) to fix input queue with very low framerates.
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-12-08: Renderer: Fixed mishandling of the the ImDrawCmd::IdxOffset field! This is an old bug but it never had an effect until some internal rendering changes in 1.86.
+//  2021-08-17: Calling io.AddFocusEvent() on ALLEGRO_EVENT_DISPLAY_SWITCH_OUT/ALLEGRO_EVENT_DISPLAY_SWITCH_IN events.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-05-19: Renderer: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-02-18: Change blending equation to preserve alpha in output buffer.
+//  2020-08-10: Inputs: Fixed horizontal mouse wheel direction.
+//  2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
+//  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
+//  2019-05-11: Inputs: Don't filter character value from ALLEGRO_EVENT_KEY_CHAR before calling AddInputCharacter().
+//  2019-04-30: Renderer: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2018-11-30: Platform: Added touchscreen support.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName/io.BackendRendererName so they can be displayed in the About Window.
+//  2018-06-13: Platform: Added clipboard support (from Allegro 5.1.12).
+//  2018-06-13: Renderer: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-06-13: Renderer: Stopped using al_draw_indexed_prim() as it is buggy in Allegro's DX9 backend.
+//  2018-06-13: Renderer: Backup/restore transform and clipping rectangle.
+//  2018-06-11: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-04-18: Misc: Renamed file from imgui_impl_a5.cpp to imgui_impl_allegro5.cpp.
+//  2018-04-18: Misc: Added support for 32-bit vertex indices to avoid conversion at runtime. Added imconfig_allegro5.h to enforce 32-bit indices when included from imgui.h.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplAllegro5_RenderDrawData() in the .h file so you can call it yourself.
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_allegro5.h"
+#include <stdint.h>     // uint64_t
+#include <cstring>      // memcpy
+
+// Allegro
+#include <allegro5/allegro.h>
+#include <allegro5/allegro_primitives.h>
+#ifdef _WIN32
+#include <allegro5/allegro_windows.h>
+#endif
+#define ALLEGRO_HAS_CLIPBOARD           (ALLEGRO_VERSION_INT >= ((5 << 24) | (1 << 16) | (12 << 8))) // Clipboard only supported from Allegro 5.1.12
+#define ALLEGRO_HAS_DRAW_INDEXED_PRIM   (ALLEGRO_VERSION_INT >= ((5 << 24) | (2 << 16) | ( 5 << 8))) // DX9 implementation of al_draw_indexed_prim() got fixed in Allegro 5.2.5
+
+// Visual Studio warnings
+#ifdef _MSC_VER
+#pragma warning (disable: 4127) // condition expression is constant
+#endif
+
+struct ImDrawVertAllegro
+{
+    ImVec2          pos;
+    ImVec2          uv;
+    ALLEGRO_COLOR   col;
+};
+
+// FIXME-OPT: Unfortunately Allegro doesn't support 32-bit packed colors so we have to convert them to 4 float as well..
+// FIXME-OPT: Consider inlining al_map_rgba()?
+// see https://github.com/liballeg/allegro5/blob/master/src/pixels.c#L554
+// and https://github.com/liballeg/allegro5/blob/master/include/allegro5/internal/aintern_pixels.h
+#define DRAW_VERT_IMGUI_TO_ALLEGRO(DST, SRC)  { (DST)->pos = (SRC)->pos; (DST)->uv = (SRC)->uv; unsigned char* c = (unsigned char*)&(SRC)->col; (DST)->col = al_map_rgba(c[0], c[1], c[2], c[3]); }
+
+// Allegro Data
+struct ImGui_ImplAllegro5_Data
+{
+    ALLEGRO_DISPLAY*            Display;
+    ALLEGRO_BITMAP*             Texture;
+    double                      Time;
+    ALLEGRO_MOUSE_CURSOR*       MouseCursorInvisible;
+    ALLEGRO_VERTEX_DECL*        VertexDecl;
+    char*                       ClipboardTextData;
+
+    ImVector<ImDrawVertAllegro> BufVertices;
+    ImVector<int>               BufIndices;
+
+    ImGui_ImplAllegro5_Data()   { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+static ImGui_ImplAllegro5_Data* ImGui_ImplAllegro5_GetBackendData()     { return ImGui::GetCurrentContext() ? (ImGui_ImplAllegro5_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr; }
+
+static void ImGui_ImplAllegro5_SetupRenderState(ImDrawData* draw_data)
+{
+    // Setup blending
+    al_set_separate_blender(ALLEGRO_ADD, ALLEGRO_ALPHA, ALLEGRO_INVERSE_ALPHA, ALLEGRO_ADD, ALLEGRO_ONE, ALLEGRO_INVERSE_ALPHA);
+
+    // Setup orthographic projection matrix
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
+    {
+        float L = draw_data->DisplayPos.x;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+        float T = draw_data->DisplayPos.y;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+        ALLEGRO_TRANSFORM transform;
+        al_identity_transform(&transform);
+        al_use_transform(&transform);
+        al_orthographic_transform(&transform, L, T, 1.0f, R, B, -1.0f);
+        al_use_projection_transform(&transform);
+    }
+}
+
+// Render function.
+void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    // Backup Allegro state that will be modified
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    ALLEGRO_TRANSFORM last_transform = *al_get_current_transform();
+    ALLEGRO_TRANSFORM last_projection_transform = *al_get_current_projection_transform();
+    int last_clip_x, last_clip_y, last_clip_w, last_clip_h;
+    al_get_clipping_rectangle(&last_clip_x, &last_clip_y, &last_clip_w, &last_clip_h);
+    int last_blender_op, last_blender_src, last_blender_dst;
+    al_get_blender(&last_blender_op, &last_blender_src, &last_blender_dst);
+
+    // Setup desired render state
+    ImGui_ImplAllegro5_SetupRenderState(draw_data);
+
+    // Render command lists
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+
+        ImVector<ImDrawVertAllegro>& vertices = bd->BufVertices;
+#if ALLEGRO_HAS_DRAW_INDEXED_PRIM
+        vertices.resize(cmd_list->VtxBuffer.Size);
+        for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
+        {
+            const ImDrawVert* src_v = &cmd_list->VtxBuffer[i];
+            ImDrawVertAllegro* dst_v = &vertices[i];
+            DRAW_VERT_IMGUI_TO_ALLEGRO(dst_v, src_v);
+        }
+        const int* indices = nullptr;
+        if (sizeof(ImDrawIdx) == 2)
+        {
+            // FIXME-OPT: Allegro doesn't support 16-bit indices.
+            // You can '#define ImDrawIdx int' in imconfig.h to request Dear ImGui to output 32-bit indices.
+            // Otherwise, we convert them from 16-bit to 32-bit at runtime here, which works perfectly but is a little wasteful.
+            bd->BufIndices.resize(cmd_list->IdxBuffer.Size);
+            for (int i = 0; i < cmd_list->IdxBuffer.Size; ++i)
+                bd->BufIndices[i] = (int)cmd_list->IdxBuffer.Data[i];
+            indices = bd->BufIndices.Data;
+        }
+        else if (sizeof(ImDrawIdx) == 4)
+        {
+            indices = (const int*)cmd_list->IdxBuffer.Data;
+        }
+#else
+        // Allegro's implementation of al_draw_indexed_prim() for DX9 was broken until 5.2.5. Unindex buffers ourselves while converting vertex format.
+        vertices.resize(cmd_list->IdxBuffer.Size);
+        for (int i = 0; i < cmd_list->IdxBuffer.Size; i++)
+        {
+            const ImDrawVert* src_v = &cmd_list->VtxBuffer[cmd_list->IdxBuffer[i]];
+            ImDrawVertAllegro* dst_v = &vertices[i];
+            DRAW_VERT_IMGUI_TO_ALLEGRO(dst_v, src_v);
+        }
+#endif
+
+        // Render command lists
+        ImVec2 clip_off = draw_data->DisplayPos;
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplAllegro5_SetupRenderState(draw_data);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+                ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle, Draw
+                ALLEGRO_BITMAP* texture = (ALLEGRO_BITMAP*)pcmd->GetTexID();
+                al_set_clipping_rectangle(clip_min.x, clip_min.y, clip_max.x - clip_min.x, clip_max.y - clip_min.y);
+#if ALLEGRO_HAS_DRAW_INDEXED_PRIM
+                al_draw_indexed_prim(&vertices[0], bd->VertexDecl, texture, &indices[pcmd->IdxOffset], pcmd->ElemCount, ALLEGRO_PRIM_TRIANGLE_LIST);
+#else
+                al_draw_prim(&vertices[0], bd->VertexDecl, texture, pcmd->IdxOffset, pcmd->IdxOffset + pcmd->ElemCount, ALLEGRO_PRIM_TRIANGLE_LIST);
+#endif
+            }
+        }
+    }
+
+    // Restore modified Allegro state
+    al_set_blender(last_blender_op, last_blender_src, last_blender_dst);
+    al_set_clipping_rectangle(last_clip_x, last_clip_y, last_clip_w, last_clip_h);
+    al_use_transform(&last_transform);
+    al_use_projection_transform(&last_projection_transform);
+}
+
+bool ImGui_ImplAllegro5_CreateDeviceObjects()
+{
+    // Build texture atlas
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
+
+    // Create texture
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    int flags = al_get_new_bitmap_flags();
+    int fmt = al_get_new_bitmap_format();
+    al_set_new_bitmap_flags(ALLEGRO_MEMORY_BITMAP | ALLEGRO_MIN_LINEAR | ALLEGRO_MAG_LINEAR);
+    al_set_new_bitmap_format(ALLEGRO_PIXEL_FORMAT_ABGR_8888_LE);
+    ALLEGRO_BITMAP* img = al_create_bitmap(width, height);
+    al_set_new_bitmap_flags(flags);
+    al_set_new_bitmap_format(fmt);
+    if (!img)
+        return false;
+
+    ALLEGRO_LOCKED_REGION* locked_img = al_lock_bitmap(img, al_get_bitmap_format(img), ALLEGRO_LOCK_WRITEONLY);
+    if (!locked_img)
+    {
+        al_destroy_bitmap(img);
+        return false;
+    }
+    memcpy(locked_img->data, pixels, sizeof(int) * width * height);
+    al_unlock_bitmap(img);
+
+    // Convert software texture to hardware texture.
+    ALLEGRO_BITMAP* cloned_img = al_clone_bitmap(img);
+    al_destroy_bitmap(img);
+    if (!cloned_img)
+        return false;
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)cloned_img);
+    bd->Texture = cloned_img;
+
+    // Create an invisible mouse cursor
+    // Because al_hide_mouse_cursor() seems to mess up with the actual inputs..
+    ALLEGRO_BITMAP* mouse_cursor = al_create_bitmap(8, 8);
+    bd->MouseCursorInvisible = al_create_mouse_cursor(mouse_cursor, 0, 0);
+    al_destroy_bitmap(mouse_cursor);
+
+    return true;
+}
+
+void ImGui_ImplAllegro5_InvalidateDeviceObjects()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    if (bd->Texture)
+    {
+        io.Fonts->SetTexID(0);
+        al_destroy_bitmap(bd->Texture);
+        bd->Texture = nullptr;
+    }
+    if (bd->MouseCursorInvisible)
+    {
+        al_destroy_mouse_cursor(bd->MouseCursorInvisible);
+        bd->MouseCursorInvisible = nullptr;
+    }
+}
+
+#if ALLEGRO_HAS_CLIPBOARD
+static const char* ImGui_ImplAllegro5_GetClipboardText(void*)
+{
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    if (bd->ClipboardTextData)
+        al_free(bd->ClipboardTextData);
+    bd->ClipboardTextData = al_get_clipboard_text(bd->Display);
+    return bd->ClipboardTextData;
+}
+
+static void ImGui_ImplAllegro5_SetClipboardText(void*, const char* text)
+{
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    al_set_clipboard_text(bd->Display, text);
+}
+#endif
+
+static ImGuiKey ImGui_ImplAllegro5_KeyCodeToImGuiKey(int key_code)
+{
+    switch (key_code)
+    {
+        case ALLEGRO_KEY_TAB: return ImGuiKey_Tab;
+        case ALLEGRO_KEY_LEFT: return ImGuiKey_LeftArrow;
+        case ALLEGRO_KEY_RIGHT: return ImGuiKey_RightArrow;
+        case ALLEGRO_KEY_UP: return ImGuiKey_UpArrow;
+        case ALLEGRO_KEY_DOWN: return ImGuiKey_DownArrow;
+        case ALLEGRO_KEY_PGUP: return ImGuiKey_PageUp;
+        case ALLEGRO_KEY_PGDN: return ImGuiKey_PageDown;
+        case ALLEGRO_KEY_HOME: return ImGuiKey_Home;
+        case ALLEGRO_KEY_END: return ImGuiKey_End;
+        case ALLEGRO_KEY_INSERT: return ImGuiKey_Insert;
+        case ALLEGRO_KEY_DELETE: return ImGuiKey_Delete;
+        case ALLEGRO_KEY_BACKSPACE: return ImGuiKey_Backspace;
+        case ALLEGRO_KEY_SPACE: return ImGuiKey_Space;
+        case ALLEGRO_KEY_ENTER: return ImGuiKey_Enter;
+        case ALLEGRO_KEY_ESCAPE: return ImGuiKey_Escape;
+        case ALLEGRO_KEY_QUOTE: return ImGuiKey_Apostrophe;
+        case ALLEGRO_KEY_COMMA: return ImGuiKey_Comma;
+        case ALLEGRO_KEY_MINUS: return ImGuiKey_Minus;
+        case ALLEGRO_KEY_FULLSTOP: return ImGuiKey_Period;
+        case ALLEGRO_KEY_SLASH: return ImGuiKey_Slash;
+        case ALLEGRO_KEY_SEMICOLON: return ImGuiKey_Semicolon;
+        case ALLEGRO_KEY_EQUALS: return ImGuiKey_Equal;
+        case ALLEGRO_KEY_OPENBRACE: return ImGuiKey_LeftBracket;
+        case ALLEGRO_KEY_BACKSLASH: return ImGuiKey_Backslash;
+        case ALLEGRO_KEY_CLOSEBRACE: return ImGuiKey_RightBracket;
+        case ALLEGRO_KEY_TILDE: return ImGuiKey_GraveAccent;
+        case ALLEGRO_KEY_CAPSLOCK: return ImGuiKey_CapsLock;
+        case ALLEGRO_KEY_SCROLLLOCK: return ImGuiKey_ScrollLock;
+        case ALLEGRO_KEY_NUMLOCK: return ImGuiKey_NumLock;
+        case ALLEGRO_KEY_PRINTSCREEN: return ImGuiKey_PrintScreen;
+        case ALLEGRO_KEY_PAUSE: return ImGuiKey_Pause;
+        case ALLEGRO_KEY_PAD_0: return ImGuiKey_Keypad0;
+        case ALLEGRO_KEY_PAD_1: return ImGuiKey_Keypad1;
+        case ALLEGRO_KEY_PAD_2: return ImGuiKey_Keypad2;
+        case ALLEGRO_KEY_PAD_3: return ImGuiKey_Keypad3;
+        case ALLEGRO_KEY_PAD_4: return ImGuiKey_Keypad4;
+        case ALLEGRO_KEY_PAD_5: return ImGuiKey_Keypad5;
+        case ALLEGRO_KEY_PAD_6: return ImGuiKey_Keypad6;
+        case ALLEGRO_KEY_PAD_7: return ImGuiKey_Keypad7;
+        case ALLEGRO_KEY_PAD_8: return ImGuiKey_Keypad8;
+        case ALLEGRO_KEY_PAD_9: return ImGuiKey_Keypad9;
+        case ALLEGRO_KEY_PAD_DELETE: return ImGuiKey_KeypadDecimal;
+        case ALLEGRO_KEY_PAD_SLASH: return ImGuiKey_KeypadDivide;
+        case ALLEGRO_KEY_PAD_ASTERISK: return ImGuiKey_KeypadMultiply;
+        case ALLEGRO_KEY_PAD_MINUS: return ImGuiKey_KeypadSubtract;
+        case ALLEGRO_KEY_PAD_PLUS: return ImGuiKey_KeypadAdd;
+        case ALLEGRO_KEY_PAD_ENTER: return ImGuiKey_KeypadEnter;
+        case ALLEGRO_KEY_PAD_EQUALS: return ImGuiKey_KeypadEqual;
+        case ALLEGRO_KEY_LCTRL: return ImGuiKey_LeftCtrl;
+        case ALLEGRO_KEY_LSHIFT: return ImGuiKey_LeftShift;
+        case ALLEGRO_KEY_ALT: return ImGuiKey_LeftAlt;
+        case ALLEGRO_KEY_LWIN: return ImGuiKey_LeftSuper;
+        case ALLEGRO_KEY_RCTRL: return ImGuiKey_RightCtrl;
+        case ALLEGRO_KEY_RSHIFT: return ImGuiKey_RightShift;
+        case ALLEGRO_KEY_ALTGR: return ImGuiKey_RightAlt;
+        case ALLEGRO_KEY_RWIN: return ImGuiKey_RightSuper;
+        case ALLEGRO_KEY_MENU: return ImGuiKey_Menu;
+        case ALLEGRO_KEY_0: return ImGuiKey_0;
+        case ALLEGRO_KEY_1: return ImGuiKey_1;
+        case ALLEGRO_KEY_2: return ImGuiKey_2;
+        case ALLEGRO_KEY_3: return ImGuiKey_3;
+        case ALLEGRO_KEY_4: return ImGuiKey_4;
+        case ALLEGRO_KEY_5: return ImGuiKey_5;
+        case ALLEGRO_KEY_6: return ImGuiKey_6;
+        case ALLEGRO_KEY_7: return ImGuiKey_7;
+        case ALLEGRO_KEY_8: return ImGuiKey_8;
+        case ALLEGRO_KEY_9: return ImGuiKey_9;
+        case ALLEGRO_KEY_A: return ImGuiKey_A;
+        case ALLEGRO_KEY_B: return ImGuiKey_B;
+        case ALLEGRO_KEY_C: return ImGuiKey_C;
+        case ALLEGRO_KEY_D: return ImGuiKey_D;
+        case ALLEGRO_KEY_E: return ImGuiKey_E;
+        case ALLEGRO_KEY_F: return ImGuiKey_F;
+        case ALLEGRO_KEY_G: return ImGuiKey_G;
+        case ALLEGRO_KEY_H: return ImGuiKey_H;
+        case ALLEGRO_KEY_I: return ImGuiKey_I;
+        case ALLEGRO_KEY_J: return ImGuiKey_J;
+        case ALLEGRO_KEY_K: return ImGuiKey_K;
+        case ALLEGRO_KEY_L: return ImGuiKey_L;
+        case ALLEGRO_KEY_M: return ImGuiKey_M;
+        case ALLEGRO_KEY_N: return ImGuiKey_N;
+        case ALLEGRO_KEY_O: return ImGuiKey_O;
+        case ALLEGRO_KEY_P: return ImGuiKey_P;
+        case ALLEGRO_KEY_Q: return ImGuiKey_Q;
+        case ALLEGRO_KEY_R: return ImGuiKey_R;
+        case ALLEGRO_KEY_S: return ImGuiKey_S;
+        case ALLEGRO_KEY_T: return ImGuiKey_T;
+        case ALLEGRO_KEY_U: return ImGuiKey_U;
+        case ALLEGRO_KEY_V: return ImGuiKey_V;
+        case ALLEGRO_KEY_W: return ImGuiKey_W;
+        case ALLEGRO_KEY_X: return ImGuiKey_X;
+        case ALLEGRO_KEY_Y: return ImGuiKey_Y;
+        case ALLEGRO_KEY_Z: return ImGuiKey_Z;
+        case ALLEGRO_KEY_F1: return ImGuiKey_F1;
+        case ALLEGRO_KEY_F2: return ImGuiKey_F2;
+        case ALLEGRO_KEY_F3: return ImGuiKey_F3;
+        case ALLEGRO_KEY_F4: return ImGuiKey_F4;
+        case ALLEGRO_KEY_F5: return ImGuiKey_F5;
+        case ALLEGRO_KEY_F6: return ImGuiKey_F6;
+        case ALLEGRO_KEY_F7: return ImGuiKey_F7;
+        case ALLEGRO_KEY_F8: return ImGuiKey_F8;
+        case ALLEGRO_KEY_F9: return ImGuiKey_F9;
+        case ALLEGRO_KEY_F10: return ImGuiKey_F10;
+        case ALLEGRO_KEY_F11: return ImGuiKey_F11;
+        case ALLEGRO_KEY_F12: return ImGuiKey_F12;
+        default: return ImGuiKey_None;
+    }
+}
+
+bool ImGui_ImplAllegro5_Init(ALLEGRO_DISPLAY* display)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplAllegro5_Data* bd = IM_NEW(ImGui_ImplAllegro5_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = io.BackendRendererName = "imgui_impl_allegro5";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;       // We can honor GetMouseCursor() values (optional)
+
+    bd->Display = display;
+
+    // Create custom vertex declaration.
+    // Unfortunately Allegro doesn't support 32-bit packed colors so we have to convert them to 4 floats.
+    // We still use a custom declaration to use 'ALLEGRO_PRIM_TEX_COORD' instead of 'ALLEGRO_PRIM_TEX_COORD_PIXEL' else we can't do a reliable conversion.
+    ALLEGRO_VERTEX_ELEMENT elems[] =
+    {
+        { ALLEGRO_PRIM_POSITION, ALLEGRO_PRIM_FLOAT_2, IM_OFFSETOF(ImDrawVertAllegro, pos) },
+        { ALLEGRO_PRIM_TEX_COORD, ALLEGRO_PRIM_FLOAT_2, IM_OFFSETOF(ImDrawVertAllegro, uv) },
+        { ALLEGRO_PRIM_COLOR_ATTR, 0, IM_OFFSETOF(ImDrawVertAllegro, col) },
+        { 0, 0, 0 }
+    };
+    bd->VertexDecl = al_create_vertex_decl(elems, sizeof(ImDrawVertAllegro));
+
+#if ALLEGRO_HAS_CLIPBOARD
+    io.SetClipboardTextFn = ImGui_ImplAllegro5_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplAllegro5_GetClipboardText;
+    io.ClipboardUserData = nullptr;
+#endif
+
+    return true;
+}
+
+void ImGui_ImplAllegro5_Shutdown()
+{
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplAllegro5_InvalidateDeviceObjects();
+    if (bd->VertexDecl)
+        al_destroy_vertex_decl(bd->VertexDecl);
+    if (bd->ClipboardTextData)
+        al_free(bd->ClipboardTextData);
+
+    io.BackendPlatformName = io.BackendRendererName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_HasMouseCursors;
+    IM_DELETE(bd);
+}
+
+// ev->keyboard.modifiers seems always zero so using that...
+static void ImGui_ImplAllegro5_UpdateKeyModifiers()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ALLEGRO_KEYBOARD_STATE keys;
+    al_get_keyboard_state(&keys);
+    io.AddKeyEvent(ImGuiMod_Ctrl, al_key_down(&keys, ALLEGRO_KEY_LCTRL) || al_key_down(&keys, ALLEGRO_KEY_RCTRL));
+    io.AddKeyEvent(ImGuiMod_Shift, al_key_down(&keys, ALLEGRO_KEY_LSHIFT) || al_key_down(&keys, ALLEGRO_KEY_RSHIFT));
+    io.AddKeyEvent(ImGuiMod_Alt, al_key_down(&keys, ALLEGRO_KEY_ALT) || al_key_down(&keys, ALLEGRO_KEY_ALTGR));
+    io.AddKeyEvent(ImGuiMod_Super, al_key_down(&keys, ALLEGRO_KEY_LWIN) || al_key_down(&keys, ALLEGRO_KEY_RWIN));
+}
+
+// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+bool ImGui_ImplAllegro5_ProcessEvent(ALLEGRO_EVENT* ev)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+
+    switch (ev->type)
+    {
+    case ALLEGRO_EVENT_MOUSE_AXES:
+        if (ev->mouse.display == bd->Display)
+        {
+            io.AddMousePosEvent(ev->mouse.x, ev->mouse.y);
+            io.AddMouseWheelEvent(-ev->mouse.dw, ev->mouse.dz);
+        }
+        return true;
+    case ALLEGRO_EVENT_MOUSE_BUTTON_DOWN:
+    case ALLEGRO_EVENT_MOUSE_BUTTON_UP:
+        if (ev->mouse.display == bd->Display && ev->mouse.button > 0 && ev->mouse.button <= 5)
+            io.AddMouseButtonEvent(ev->mouse.button - 1, ev->type == ALLEGRO_EVENT_MOUSE_BUTTON_DOWN);
+        return true;
+    case ALLEGRO_EVENT_TOUCH_MOVE:
+        if (ev->touch.display == bd->Display)
+            io.AddMousePosEvent(ev->touch.x, ev->touch.y);
+        return true;
+    case ALLEGRO_EVENT_TOUCH_BEGIN:
+    case ALLEGRO_EVENT_TOUCH_END:
+    case ALLEGRO_EVENT_TOUCH_CANCEL:
+        if (ev->touch.display == bd->Display && ev->touch.primary)
+            io.AddMouseButtonEvent(0, ev->type == ALLEGRO_EVENT_TOUCH_BEGIN);
+        return true;
+    case ALLEGRO_EVENT_MOUSE_LEAVE_DISPLAY:
+        if (ev->mouse.display == bd->Display)
+            io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+        return true;
+    case ALLEGRO_EVENT_KEY_CHAR:
+        if (ev->keyboard.display == bd->Display)
+            if (ev->keyboard.unichar != 0)
+                io.AddInputCharacter((unsigned int)ev->keyboard.unichar);
+        return true;
+    case ALLEGRO_EVENT_KEY_DOWN:
+    case ALLEGRO_EVENT_KEY_UP:
+        if (ev->keyboard.display == bd->Display)
+        {
+            ImGui_ImplAllegro5_UpdateKeyModifiers();
+            ImGuiKey key = ImGui_ImplAllegro5_KeyCodeToImGuiKey(ev->keyboard.keycode);
+            io.AddKeyEvent(key, (ev->type == ALLEGRO_EVENT_KEY_DOWN));
+            io.SetKeyEventNativeData(key, ev->keyboard.keycode, -1); // To support legacy indexing (<1.87 user code)
+        }
+        return true;
+    case ALLEGRO_EVENT_DISPLAY_SWITCH_OUT:
+        if (ev->display.source == bd->Display)
+            io.AddFocusEvent(false);
+        return true;
+    case ALLEGRO_EVENT_DISPLAY_SWITCH_IN:
+        if (ev->display.source == bd->Display)
+        {
+            io.AddFocusEvent(true);
+#if defined(ALLEGRO_UNSTABLE)
+            al_clear_keyboard_state(bd->Display);
+#endif
+        }
+        return true;
+    }
+    return false;
+}
+
+static void ImGui_ImplAllegro5_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return;
+
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        al_set_mouse_cursor(bd->Display, bd->MouseCursorInvisible);
+    }
+    else
+    {
+        ALLEGRO_SYSTEM_MOUSE_CURSOR cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_DEFAULT;
+        switch (imgui_cursor)
+        {
+        case ImGuiMouseCursor_TextInput:    cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_EDIT; break;
+        case ImGuiMouseCursor_ResizeAll:    cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_MOVE; break;
+        case ImGuiMouseCursor_ResizeNS:     cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_N; break;
+        case ImGuiMouseCursor_ResizeEW:     cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_E; break;
+        case ImGuiMouseCursor_ResizeNESW:   cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_NE; break;
+        case ImGuiMouseCursor_ResizeNWSE:   cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_RESIZE_NW; break;
+        case ImGuiMouseCursor_NotAllowed:   cursor_id = ALLEGRO_SYSTEM_MOUSE_CURSOR_UNAVAILABLE; break;
+        }
+        al_set_system_mouse_cursor(bd->Display, cursor_id);
+    }
+}
+
+void ImGui_ImplAllegro5_NewFrame()
+{
+    ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplAllegro5_Init()?");
+
+    if (!bd->Texture)
+        ImGui_ImplAllegro5_CreateDeviceObjects();
+
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    w = al_get_display_width(bd->Display);
+    h = al_get_display_height(bd->Display);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+
+    // Setup time step
+    double current_time = al_get_time();
+    io.DeltaTime = bd->Time > 0.0 ? (float)(current_time - bd->Time) : (float)(1.0f / 60.0f);
+    bd->Time = current_time;
+
+    // Setup mouse cursor shape
+    ImGui_ImplAllegro5_UpdateMouseCursor();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_allegro5.h

@@ -0,0 +1,38 @@
+// dear imgui: Renderer + Platform Backend for Allegro 5
+// (Info: Allegro 5 is a cross-platform general purpose library for handling windows, inputs, graphics, etc.)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ALLEGRO_BITMAP*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Clipboard support (from Allegro 5.1.12)
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Issues:
+//  [ ] Renderer: The renderer is suboptimal as we need to unindex our buffers and convert vertices manually.
+//  [ ] Platform: Missing gamepad support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct ALLEGRO_DISPLAY;
+union ALLEGRO_EVENT;
+
+IMGUI_IMPL_API bool     ImGui_ImplAllegro5_Init(ALLEGRO_DISPLAY* display);
+IMGUI_IMPL_API void     ImGui_ImplAllegro5_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplAllegro5_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data);
+IMGUI_IMPL_API bool     ImGui_ImplAllegro5_ProcessEvent(ALLEGRO_EVENT* event);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API bool     ImGui_ImplAllegro5_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplAllegro5_InvalidateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_android.cpp

@@ -0,0 +1,304 @@
+// dear imgui: Platform Binding for Android native app
+// This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
+
+// Implemented features:
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
+// Missing features:
+//  [ ] Platform: Clipboard support.
+//  [ ] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [ ] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+// Important:
+//  - Consider using SDL or GLFW backend on Android, which will be more full-featured than this.
+//  - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)
+//  - FIXME: Unicode character inputs needs to be passed by Dear ImGui by the application (see examples/ and issue #3446)
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-03-04: Initial version.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_android.h"
+#include <time.h>
+#include <android/native_window.h>
+#include <android/input.h>
+#include <android/keycodes.h>
+#include <android/log.h>
+
+// Android data
+static double                                   g_Time = 0.0;
+static ANativeWindow*                           g_Window;
+static char                                     g_LogTag[] = "ImGuiExample";
+
+static ImGuiKey ImGui_ImplAndroid_KeyCodeToImGuiKey(int32_t key_code)
+{
+    switch (key_code)
+    {
+        case AKEYCODE_TAB:                  return ImGuiKey_Tab;
+        case AKEYCODE_DPAD_LEFT:            return ImGuiKey_LeftArrow;
+        case AKEYCODE_DPAD_RIGHT:           return ImGuiKey_RightArrow;
+        case AKEYCODE_DPAD_UP:              return ImGuiKey_UpArrow;
+        case AKEYCODE_DPAD_DOWN:            return ImGuiKey_DownArrow;
+        case AKEYCODE_PAGE_UP:              return ImGuiKey_PageUp;
+        case AKEYCODE_PAGE_DOWN:            return ImGuiKey_PageDown;
+        case AKEYCODE_MOVE_HOME:            return ImGuiKey_Home;
+        case AKEYCODE_MOVE_END:             return ImGuiKey_End;
+        case AKEYCODE_INSERT:               return ImGuiKey_Insert;
+        case AKEYCODE_FORWARD_DEL:          return ImGuiKey_Delete;
+        case AKEYCODE_DEL:                  return ImGuiKey_Backspace;
+        case AKEYCODE_SPACE:                return ImGuiKey_Space;
+        case AKEYCODE_ENTER:                return ImGuiKey_Enter;
+        case AKEYCODE_ESCAPE:               return ImGuiKey_Escape;
+        case AKEYCODE_APOSTROPHE:           return ImGuiKey_Apostrophe;
+        case AKEYCODE_COMMA:                return ImGuiKey_Comma;
+        case AKEYCODE_MINUS:                return ImGuiKey_Minus;
+        case AKEYCODE_PERIOD:               return ImGuiKey_Period;
+        case AKEYCODE_SLASH:                return ImGuiKey_Slash;
+        case AKEYCODE_SEMICOLON:            return ImGuiKey_Semicolon;
+        case AKEYCODE_EQUALS:               return ImGuiKey_Equal;
+        case AKEYCODE_LEFT_BRACKET:         return ImGuiKey_LeftBracket;
+        case AKEYCODE_BACKSLASH:            return ImGuiKey_Backslash;
+        case AKEYCODE_RIGHT_BRACKET:        return ImGuiKey_RightBracket;
+        case AKEYCODE_GRAVE:                return ImGuiKey_GraveAccent;
+        case AKEYCODE_CAPS_LOCK:            return ImGuiKey_CapsLock;
+        case AKEYCODE_SCROLL_LOCK:          return ImGuiKey_ScrollLock;
+        case AKEYCODE_NUM_LOCK:             return ImGuiKey_NumLock;
+        case AKEYCODE_SYSRQ:                return ImGuiKey_PrintScreen;
+        case AKEYCODE_BREAK:                return ImGuiKey_Pause;
+        case AKEYCODE_NUMPAD_0:             return ImGuiKey_Keypad0;
+        case AKEYCODE_NUMPAD_1:             return ImGuiKey_Keypad1;
+        case AKEYCODE_NUMPAD_2:             return ImGuiKey_Keypad2;
+        case AKEYCODE_NUMPAD_3:             return ImGuiKey_Keypad3;
+        case AKEYCODE_NUMPAD_4:             return ImGuiKey_Keypad4;
+        case AKEYCODE_NUMPAD_5:             return ImGuiKey_Keypad5;
+        case AKEYCODE_NUMPAD_6:             return ImGuiKey_Keypad6;
+        case AKEYCODE_NUMPAD_7:             return ImGuiKey_Keypad7;
+        case AKEYCODE_NUMPAD_8:             return ImGuiKey_Keypad8;
+        case AKEYCODE_NUMPAD_9:             return ImGuiKey_Keypad9;
+        case AKEYCODE_NUMPAD_DOT:           return ImGuiKey_KeypadDecimal;
+        case AKEYCODE_NUMPAD_DIVIDE:        return ImGuiKey_KeypadDivide;
+        case AKEYCODE_NUMPAD_MULTIPLY:      return ImGuiKey_KeypadMultiply;
+        case AKEYCODE_NUMPAD_SUBTRACT:      return ImGuiKey_KeypadSubtract;
+        case AKEYCODE_NUMPAD_ADD:           return ImGuiKey_KeypadAdd;
+        case AKEYCODE_NUMPAD_ENTER:         return ImGuiKey_KeypadEnter;
+        case AKEYCODE_NUMPAD_EQUALS:        return ImGuiKey_KeypadEqual;
+        case AKEYCODE_CTRL_LEFT:            return ImGuiKey_LeftCtrl;
+        case AKEYCODE_SHIFT_LEFT:           return ImGuiKey_LeftShift;
+        case AKEYCODE_ALT_LEFT:             return ImGuiKey_LeftAlt;
+        case AKEYCODE_META_LEFT:            return ImGuiKey_LeftSuper;
+        case AKEYCODE_CTRL_RIGHT:           return ImGuiKey_RightCtrl;
+        case AKEYCODE_SHIFT_RIGHT:          return ImGuiKey_RightShift;
+        case AKEYCODE_ALT_RIGHT:            return ImGuiKey_RightAlt;
+        case AKEYCODE_META_RIGHT:           return ImGuiKey_RightSuper;
+        case AKEYCODE_MENU:                 return ImGuiKey_Menu;
+        case AKEYCODE_0:                    return ImGuiKey_0;
+        case AKEYCODE_1:                    return ImGuiKey_1;
+        case AKEYCODE_2:                    return ImGuiKey_2;
+        case AKEYCODE_3:                    return ImGuiKey_3;
+        case AKEYCODE_4:                    return ImGuiKey_4;
+        case AKEYCODE_5:                    return ImGuiKey_5;
+        case AKEYCODE_6:                    return ImGuiKey_6;
+        case AKEYCODE_7:                    return ImGuiKey_7;
+        case AKEYCODE_8:                    return ImGuiKey_8;
+        case AKEYCODE_9:                    return ImGuiKey_9;
+        case AKEYCODE_A:                    return ImGuiKey_A;
+        case AKEYCODE_B:                    return ImGuiKey_B;
+        case AKEYCODE_C:                    return ImGuiKey_C;
+        case AKEYCODE_D:                    return ImGuiKey_D;
+        case AKEYCODE_E:                    return ImGuiKey_E;
+        case AKEYCODE_F:                    return ImGuiKey_F;
+        case AKEYCODE_G:                    return ImGuiKey_G;
+        case AKEYCODE_H:                    return ImGuiKey_H;
+        case AKEYCODE_I:                    return ImGuiKey_I;
+        case AKEYCODE_J:                    return ImGuiKey_J;
+        case AKEYCODE_K:                    return ImGuiKey_K;
+        case AKEYCODE_L:                    return ImGuiKey_L;
+        case AKEYCODE_M:                    return ImGuiKey_M;
+        case AKEYCODE_N:                    return ImGuiKey_N;
+        case AKEYCODE_O:                    return ImGuiKey_O;
+        case AKEYCODE_P:                    return ImGuiKey_P;
+        case AKEYCODE_Q:                    return ImGuiKey_Q;
+        case AKEYCODE_R:                    return ImGuiKey_R;
+        case AKEYCODE_S:                    return ImGuiKey_S;
+        case AKEYCODE_T:                    return ImGuiKey_T;
+        case AKEYCODE_U:                    return ImGuiKey_U;
+        case AKEYCODE_V:                    return ImGuiKey_V;
+        case AKEYCODE_W:                    return ImGuiKey_W;
+        case AKEYCODE_X:                    return ImGuiKey_X;
+        case AKEYCODE_Y:                    return ImGuiKey_Y;
+        case AKEYCODE_Z:                    return ImGuiKey_Z;
+        case AKEYCODE_F1:                   return ImGuiKey_F1;
+        case AKEYCODE_F2:                   return ImGuiKey_F2;
+        case AKEYCODE_F3:                   return ImGuiKey_F3;
+        case AKEYCODE_F4:                   return ImGuiKey_F4;
+        case AKEYCODE_F5:                   return ImGuiKey_F5;
+        case AKEYCODE_F6:                   return ImGuiKey_F6;
+        case AKEYCODE_F7:                   return ImGuiKey_F7;
+        case AKEYCODE_F8:                   return ImGuiKey_F8;
+        case AKEYCODE_F9:                   return ImGuiKey_F9;
+        case AKEYCODE_F10:                  return ImGuiKey_F10;
+        case AKEYCODE_F11:                  return ImGuiKey_F11;
+        case AKEYCODE_F12:                  return ImGuiKey_F12;
+        default:                            return ImGuiKey_None;
+    }
+}
+
+int32_t ImGui_ImplAndroid_HandleInputEvent(AInputEvent* input_event)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    int32_t event_type = AInputEvent_getType(input_event);
+    switch (event_type)
+    {
+    case AINPUT_EVENT_TYPE_KEY:
+    {
+        int32_t event_key_code = AKeyEvent_getKeyCode(input_event);
+        int32_t event_scan_code = AKeyEvent_getScanCode(input_event);
+        int32_t event_action = AKeyEvent_getAction(input_event);
+        int32_t event_meta_state = AKeyEvent_getMetaState(input_event);
+
+        io.AddKeyEvent(ImGuiMod_Ctrl,  (event_meta_state & AMETA_CTRL_ON)  != 0);
+        io.AddKeyEvent(ImGuiMod_Shift, (event_meta_state & AMETA_SHIFT_ON) != 0);
+        io.AddKeyEvent(ImGuiMod_Alt,   (event_meta_state & AMETA_ALT_ON)   != 0);
+        io.AddKeyEvent(ImGuiMod_Super, (event_meta_state & AMETA_META_ON)  != 0);
+
+        switch (event_action)
+        {
+        // FIXME: AKEY_EVENT_ACTION_DOWN and AKEY_EVENT_ACTION_UP occur at once as soon as a touch pointer
+        // goes up from a key. We use a simple key event queue/ and process one event per key per frame in
+        // ImGui_ImplAndroid_NewFrame()...or consider using IO queue, if suitable: https://github.com/ocornut/imgui/issues/2787
+        case AKEY_EVENT_ACTION_DOWN:
+        case AKEY_EVENT_ACTION_UP:
+        {
+            ImGuiKey key = ImGui_ImplAndroid_KeyCodeToImGuiKey(event_key_code);
+            if (key != ImGuiKey_None && (event_action == AKEY_EVENT_ACTION_DOWN || event_action == AKEY_EVENT_ACTION_UP))
+            {
+                io.AddKeyEvent(key, event_action == AKEY_EVENT_ACTION_DOWN);
+                io.SetKeyEventNativeData(key, event_key_code, event_scan_code);
+            }
+
+            break;
+        }
+        default:
+            break;
+        }
+        break;
+    }
+    case AINPUT_EVENT_TYPE_MOTION:
+    {
+        int32_t event_action = AMotionEvent_getAction(input_event);
+        int32_t event_pointer_index = (event_action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK) >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
+        event_action &= AMOTION_EVENT_ACTION_MASK;
+
+        switch (AMotionEvent_getToolType(input_event, event_pointer_index))
+        {
+        case AMOTION_EVENT_TOOL_TYPE_MOUSE:
+            io.AddMouseSourceEvent(ImGuiMouseSource_Mouse);
+            break;
+        case AMOTION_EVENT_TOOL_TYPE_STYLUS:
+        case AMOTION_EVENT_TOOL_TYPE_ERASER:
+            io.AddMouseSourceEvent(ImGuiMouseSource_Pen);
+            break;
+        case AMOTION_EVENT_TOOL_TYPE_FINGER:
+        default:
+            io.AddMouseSourceEvent(ImGuiMouseSource_TouchScreen);
+            break;
+        }
+
+        switch (event_action)
+        {
+        case AMOTION_EVENT_ACTION_DOWN:
+        case AMOTION_EVENT_ACTION_UP:
+            // Physical mouse buttons (and probably other physical devices) also invoke the actions AMOTION_EVENT_ACTION_DOWN/_UP,
+            // but we have to process them separately to identify the actual button pressed. This is done below via
+            // AMOTION_EVENT_ACTION_BUTTON_PRESS/_RELEASE. Here, we only process "FINGER" input (and "UNKNOWN", as a fallback).
+            if((AMotionEvent_getToolType(input_event, event_pointer_index) == AMOTION_EVENT_TOOL_TYPE_FINGER)
+            || (AMotionEvent_getToolType(input_event, event_pointer_index) == AMOTION_EVENT_TOOL_TYPE_UNKNOWN))
+            {
+                io.AddMousePosEvent(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index));
+                io.AddMouseButtonEvent(0, event_action == AMOTION_EVENT_ACTION_DOWN);
+            }
+            break;
+        case AMOTION_EVENT_ACTION_BUTTON_PRESS:
+        case AMOTION_EVENT_ACTION_BUTTON_RELEASE:
+            {
+                int32_t button_state = AMotionEvent_getButtonState(input_event);
+                io.AddMouseButtonEvent(0, (button_state & AMOTION_EVENT_BUTTON_PRIMARY) != 0);
+                io.AddMouseButtonEvent(1, (button_state & AMOTION_EVENT_BUTTON_SECONDARY) != 0);
+                io.AddMouseButtonEvent(2, (button_state & AMOTION_EVENT_BUTTON_TERTIARY) != 0);
+            }
+            break;
+        case AMOTION_EVENT_ACTION_HOVER_MOVE: // Hovering: Tool moves while NOT pressed (such as a physical mouse)
+        case AMOTION_EVENT_ACTION_MOVE:       // Touch pointer moves while DOWN
+            io.AddMousePosEvent(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index));
+            break;
+        case AMOTION_EVENT_ACTION_SCROLL:
+            io.AddMouseWheelEvent(AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_HSCROLL, event_pointer_index), AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_VSCROLL, event_pointer_index));
+            break;
+        default:
+            break;
+        }
+    }
+        return 1;
+    default:
+        break;
+    }
+
+    return 0;
+}
+
+bool ImGui_ImplAndroid_Init(ANativeWindow* window)
+{
+    g_Window = window;
+    g_Time = 0.0;
+
+    // Setup backend capabilities flags
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendPlatformName = "imgui_impl_android";
+
+    return true;
+}
+
+void ImGui_ImplAndroid_Shutdown()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendPlatformName = nullptr;
+}
+
+void ImGui_ImplAndroid_NewFrame()
+{
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int32_t window_width = ANativeWindow_getWidth(g_Window);
+    int32_t window_height = ANativeWindow_getHeight(g_Window);
+    int display_width = window_width;
+    int display_height = window_height;
+
+    io.DisplaySize = ImVec2((float)window_width, (float)window_height);
+    if (window_width > 0 && window_height > 0)
+        io.DisplayFramebufferScale = ImVec2((float)display_width / window_width, (float)display_height / window_height);
+
+    // Setup time step
+    struct timespec current_timespec;
+    clock_gettime(CLOCK_MONOTONIC, &current_timespec);
+    double current_time = (double)(current_timespec.tv_sec) + (current_timespec.tv_nsec / 1000000000.0);
+    io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
+    g_Time = current_time;
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_android.h

@@ -0,0 +1,36 @@
+// dear imgui: Platform Binding for Android native app
+// This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
+
+// Implemented features:
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
+// Missing features:
+//  [ ] Platform: Clipboard support.
+//  [ ] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [ ] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+// Important:
+//  - Consider using SDL or GLFW backend on Android, which will be more full-featured than this.
+//  - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)
+//  - FIXME: Unicode character inputs needs to be passed by Dear ImGui by the application (see examples/ and issue #3446)
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct ANativeWindow;
+struct AInputEvent;
+
+IMGUI_IMPL_API bool     ImGui_ImplAndroid_Init(ANativeWindow* window);
+IMGUI_IMPL_API int32_t  ImGui_ImplAndroid_HandleInputEvent(AInputEvent* input_event);
+IMGUI_IMPL_API void     ImGui_ImplAndroid_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplAndroid_NewFrame();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx10.cpp

@@ -0,0 +1,589 @@
+// dear imgui: Renderer Backend for DirectX10
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-05-19: DirectX10: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-02-18: DirectX10: Change blending equation to preserve alpha in output buffer.
+//  2019-07-21: DirectX10: Backup, clear and restore Geometry Shader is any is bound when calling ImGui_ImplDX10_RenderDrawData().
+//  2019-05-29: DirectX10: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: DirectX10: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2018-12-03: Misc: Added #pragma comment statement to automatically link with d3dcompiler.lib when using D3DCompile().
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-07-13: DirectX10: Fixed unreleased resources in Init and Shutdown functions.
+//  2018-06-08: Misc: Extracted imgui_impl_dx10.cpp/.h away from the old combined DX10+Win32 example.
+//  2018-06-08: DirectX10: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-04-09: Misc: Fixed erroneous call to io.Fonts->ClearInputData() + ClearTexData() that was left in DX10 example but removed in 1.47 (Nov 2015) on other backends.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX10_RenderDrawData() in the .h file so you can call it yourself.
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2016-05-07: DirectX10: Disabling depth-write.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_dx10.h"
+
+// DirectX
+#include <stdio.h>
+#include <d3d10_1.h>
+#include <d3d10.h>
+#include <d3dcompiler.h>
+#ifdef _MSC_VER
+#pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
+#endif
+
+// DirectX data
+struct ImGui_ImplDX10_Data
+{
+    ID3D10Device*               pd3dDevice;
+    IDXGIFactory*               pFactory;
+    ID3D10Buffer*               pVB;
+    ID3D10Buffer*               pIB;
+    ID3D10VertexShader*         pVertexShader;
+    ID3D10InputLayout*          pInputLayout;
+    ID3D10Buffer*               pVertexConstantBuffer;
+    ID3D10PixelShader*          pPixelShader;
+    ID3D10SamplerState*         pFontSampler;
+    ID3D10ShaderResourceView*   pFontTextureView;
+    ID3D10RasterizerState*      pRasterizerState;
+    ID3D10BlendState*           pBlendState;
+    ID3D10DepthStencilState*    pDepthStencilState;
+    int                         VertexBufferSize;
+    int                         IndexBufferSize;
+
+    ImGui_ImplDX10_Data()       { memset((void*)this, 0, sizeof(*this)); VertexBufferSize = 5000; IndexBufferSize = 10000; }
+};
+
+struct VERTEX_CONSTANT_BUFFER_DX10
+{
+    float   mvp[4][4];
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplDX10_Data* ImGui_ImplDX10_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplDX10_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+static void ImGui_ImplDX10_SetupRenderState(ImDrawData* draw_data, ID3D10Device* ctx)
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+
+    // Setup viewport
+    D3D10_VIEWPORT vp;
+    memset(&vp, 0, sizeof(D3D10_VIEWPORT));
+    vp.Width = (UINT)draw_data->DisplaySize.x;
+    vp.Height = (UINT)draw_data->DisplaySize.y;
+    vp.MinDepth = 0.0f;
+    vp.MaxDepth = 1.0f;
+    vp.TopLeftX = vp.TopLeftY = 0;
+    ctx->RSSetViewports(1, &vp);
+
+    // Bind shader and vertex buffers
+    unsigned int stride = sizeof(ImDrawVert);
+    unsigned int offset = 0;
+    ctx->IASetInputLayout(bd->pInputLayout);
+    ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
+    ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
+    ctx->IASetPrimitiveTopology(D3D10_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    ctx->VSSetShader(bd->pVertexShader);
+    ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
+    ctx->PSSetShader(bd->pPixelShader);
+    ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
+    ctx->GSSetShader(nullptr);
+
+    // Setup render state
+    const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
+    ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
+    ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
+    ctx->RSSetState(bd->pRasterizerState);
+}
+
+// Render function
+void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    ID3D10Device* ctx = bd->pd3dDevice;
+
+    // Create and grow vertex/index buffers if needed
+    if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
+    {
+        if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
+        bd->VertexBufferSize = draw_data->TotalVtxCount + 5000;
+        D3D10_BUFFER_DESC desc;
+        memset(&desc, 0, sizeof(D3D10_BUFFER_DESC));
+        desc.Usage = D3D10_USAGE_DYNAMIC;
+        desc.ByteWidth = bd->VertexBufferSize * sizeof(ImDrawVert);
+        desc.BindFlags = D3D10_BIND_VERTEX_BUFFER;
+        desc.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
+        desc.MiscFlags = 0;
+        if (ctx->CreateBuffer(&desc, nullptr, &bd->pVB) < 0)
+            return;
+    }
+
+    if (!bd->pIB || bd->IndexBufferSize < draw_data->TotalIdxCount)
+    {
+        if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
+        bd->IndexBufferSize = draw_data->TotalIdxCount + 10000;
+        D3D10_BUFFER_DESC desc;
+        memset(&desc, 0, sizeof(D3D10_BUFFER_DESC));
+        desc.Usage = D3D10_USAGE_DYNAMIC;
+        desc.ByteWidth = bd->IndexBufferSize * sizeof(ImDrawIdx);
+        desc.BindFlags = D3D10_BIND_INDEX_BUFFER;
+        desc.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
+        if (ctx->CreateBuffer(&desc, nullptr, &bd->pIB) < 0)
+            return;
+    }
+
+    // Copy and convert all vertices into a single contiguous buffer
+    ImDrawVert* vtx_dst = nullptr;
+    ImDrawIdx* idx_dst = nullptr;
+    bd->pVB->Map(D3D10_MAP_WRITE_DISCARD, 0, (void**)&vtx_dst);
+    bd->pIB->Map(D3D10_MAP_WRITE_DISCARD, 0, (void**)&idx_dst);
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += cmd_list->VtxBuffer.Size;
+        idx_dst += cmd_list->IdxBuffer.Size;
+    }
+    bd->pVB->Unmap();
+    bd->pIB->Unmap();
+
+    // Setup orthographic projection matrix into our constant buffer
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
+    {
+        void* mapped_resource;
+        if (bd->pVertexConstantBuffer->Map(D3D10_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
+            return;
+        VERTEX_CONSTANT_BUFFER_DX10* constant_buffer = (VERTEX_CONSTANT_BUFFER_DX10*)mapped_resource;
+        float L = draw_data->DisplayPos.x;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+        float T = draw_data->DisplayPos.y;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+        float mvp[4][4] =
+        {
+            { 2.0f/(R-L),   0.0f,           0.0f,       0.0f },
+            { 0.0f,         2.0f/(T-B),     0.0f,       0.0f },
+            { 0.0f,         0.0f,           0.5f,       0.0f },
+            { (R+L)/(L-R),  (T+B)/(B-T),    0.5f,       1.0f },
+        };
+        memcpy(&constant_buffer->mvp, mvp, sizeof(mvp));
+        bd->pVertexConstantBuffer->Unmap();
+    }
+
+    // Backup DX state that will be modified to restore it afterwards (unfortunately this is very ugly looking and verbose. Close your eyes!)
+    struct BACKUP_DX10_STATE
+    {
+        UINT                        ScissorRectsCount, ViewportsCount;
+        D3D10_RECT                  ScissorRects[D3D10_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
+        D3D10_VIEWPORT              Viewports[D3D10_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
+        ID3D10RasterizerState*      RS;
+        ID3D10BlendState*           BlendState;
+        FLOAT                       BlendFactor[4];
+        UINT                        SampleMask;
+        UINT                        StencilRef;
+        ID3D10DepthStencilState*    DepthStencilState;
+        ID3D10ShaderResourceView*   PSShaderResource;
+        ID3D10SamplerState*         PSSampler;
+        ID3D10PixelShader*          PS;
+        ID3D10VertexShader*         VS;
+        ID3D10GeometryShader*       GS;
+        D3D10_PRIMITIVE_TOPOLOGY    PrimitiveTopology;
+        ID3D10Buffer*               IndexBuffer, *VertexBuffer, *VSConstantBuffer;
+        UINT                        IndexBufferOffset, VertexBufferStride, VertexBufferOffset;
+        DXGI_FORMAT                 IndexBufferFormat;
+        ID3D10InputLayout*          InputLayout;
+    };
+    BACKUP_DX10_STATE old = {};
+    old.ScissorRectsCount = old.ViewportsCount = D3D10_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE;
+    ctx->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
+    ctx->RSGetViewports(&old.ViewportsCount, old.Viewports);
+    ctx->RSGetState(&old.RS);
+    ctx->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
+    ctx->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
+    ctx->PSGetShaderResources(0, 1, &old.PSShaderResource);
+    ctx->PSGetSamplers(0, 1, &old.PSSampler);
+    ctx->PSGetShader(&old.PS);
+    ctx->VSGetShader(&old.VS);
+    ctx->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
+    ctx->GSGetShader(&old.GS);
+    ctx->IAGetPrimitiveTopology(&old.PrimitiveTopology);
+    ctx->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
+    ctx->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
+    ctx->IAGetInputLayout(&old.InputLayout);
+
+    // Setup desired DX state
+    ImGui_ImplDX10_SetupRenderState(draw_data, ctx);
+
+    // Render command lists
+    // (Because we merged all buffers into a single one, we maintain our own offset into them)
+    int global_vtx_offset = 0;
+    int global_idx_offset = 0;
+    ImVec2 clip_off = draw_data->DisplayPos;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplDX10_SetupRenderState(draw_data, ctx);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+                ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle
+                const D3D10_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                ctx->RSSetScissorRects(1, &r);
+
+                // Bind texture, Draw
+                ID3D10ShaderResourceView* texture_srv = (ID3D10ShaderResourceView*)pcmd->GetTexID();
+                ctx->PSSetShaderResources(0, 1, &texture_srv);
+                ctx->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
+            }
+        }
+        global_idx_offset += cmd_list->IdxBuffer.Size;
+        global_vtx_offset += cmd_list->VtxBuffer.Size;
+    }
+
+    // Restore modified DX state
+    ctx->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
+    ctx->RSSetViewports(old.ViewportsCount, old.Viewports);
+    ctx->RSSetState(old.RS); if (old.RS) old.RS->Release();
+    ctx->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
+    ctx->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
+    ctx->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
+    ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
+    ctx->PSSetShader(old.PS); if (old.PS) old.PS->Release();
+    ctx->VSSetShader(old.VS); if (old.VS) old.VS->Release();
+    ctx->GSSetShader(old.GS); if (old.GS) old.GS->Release();
+    ctx->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
+    ctx->IASetPrimitiveTopology(old.PrimitiveTopology);
+    ctx->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
+    ctx->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
+    ctx->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
+}
+
+static void ImGui_ImplDX10_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
+
+    // Upload texture to graphics system
+    {
+        D3D10_TEXTURE2D_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Width = width;
+        desc.Height = height;
+        desc.MipLevels = 1;
+        desc.ArraySize = 1;
+        desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        desc.SampleDesc.Count = 1;
+        desc.Usage = D3D10_USAGE_DEFAULT;
+        desc.BindFlags = D3D10_BIND_SHADER_RESOURCE;
+        desc.CPUAccessFlags = 0;
+
+        ID3D10Texture2D* pTexture = nullptr;
+        D3D10_SUBRESOURCE_DATA subResource;
+        subResource.pSysMem = pixels;
+        subResource.SysMemPitch = desc.Width * 4;
+        subResource.SysMemSlicePitch = 0;
+        bd->pd3dDevice->CreateTexture2D(&desc, &subResource, &pTexture);
+        IM_ASSERT(pTexture != nullptr);
+
+        // Create texture view
+        D3D10_SHADER_RESOURCE_VIEW_DESC srv_desc;
+        ZeroMemory(&srv_desc, sizeof(srv_desc));
+        srv_desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        srv_desc.ViewDimension = D3D10_SRV_DIMENSION_TEXTURE2D;
+        srv_desc.Texture2D.MipLevels = desc.MipLevels;
+        srv_desc.Texture2D.MostDetailedMip = 0;
+        bd->pd3dDevice->CreateShaderResourceView(pTexture, &srv_desc, &bd->pFontTextureView);
+        pTexture->Release();
+    }
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)bd->pFontTextureView);
+
+    // Create texture sampler
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    {
+        D3D10_SAMPLER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Filter = D3D10_FILTER_MIN_MAG_MIP_LINEAR;
+        desc.AddressU = D3D10_TEXTURE_ADDRESS_WRAP;
+        desc.AddressV = D3D10_TEXTURE_ADDRESS_WRAP;
+        desc.AddressW = D3D10_TEXTURE_ADDRESS_WRAP;
+        desc.MipLODBias = 0.f;
+        desc.ComparisonFunc = D3D10_COMPARISON_ALWAYS;
+        desc.MinLOD = 0.f;
+        desc.MaxLOD = 0.f;
+        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+    }
+}
+
+bool    ImGui_ImplDX10_CreateDeviceObjects()
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    if (!bd->pd3dDevice)
+        return false;
+    if (bd->pFontSampler)
+        ImGui_ImplDX10_InvalidateDeviceObjects();
+
+    // By using D3DCompile() from <d3dcompiler.h> / d3dcompiler.lib, we introduce a dependency to a given version of d3dcompiler_XX.dll (see D3DCOMPILER_DLL_A)
+    // If you would like to use this DX10 sample code but remove this dependency you can:
+    //  1) compile once, save the compiled shader blobs into a file or source code and pass them to CreateVertexShader()/CreatePixelShader() [preferred solution]
+    //  2) use code to detect any version of the DLL and grab a pointer to D3DCompile from the DLL.
+    // See https://github.com/ocornut/imgui/pull/638 for sources and details.
+
+    // Create the vertex shader
+    {
+        static const char* vertexShader =
+            "cbuffer vertexBuffer : register(b0) \
+            {\
+              float4x4 ProjectionMatrix; \
+            };\
+            struct VS_INPUT\
+            {\
+              float2 pos : POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            struct PS_INPUT\
+            {\
+              float4 pos : SV_POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            PS_INPUT main(VS_INPUT input)\
+            {\
+              PS_INPUT output;\
+              output.pos = mul( ProjectionMatrix, float4(input.pos.xy, 0.f, 1.f));\
+              output.col = input.col;\
+              output.uv  = input.uv;\
+              return output;\
+            }";
+
+        ID3DBlob* vertexShaderBlob;
+        if (FAILED(D3DCompile(vertexShader, strlen(vertexShader), nullptr, nullptr, nullptr, "main", "vs_4_0", 0, 0, &vertexShaderBlob, nullptr)))
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        if (bd->pd3dDevice->CreateVertexShader(vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), &bd->pVertexShader) != S_OK)
+        {
+            vertexShaderBlob->Release();
+            return false;
+        }
+
+        // Create the input layout
+        D3D10_INPUT_ELEMENT_DESC local_layout[] =
+        {
+            { "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, pos), D3D10_INPUT_PER_VERTEX_DATA, 0 },
+            { "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, uv),  D3D10_INPUT_PER_VERTEX_DATA, 0 },
+            { "COLOR",    0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (UINT)IM_OFFSETOF(ImDrawVert, col), D3D10_INPUT_PER_VERTEX_DATA, 0 },
+        };
+        if (bd->pd3dDevice->CreateInputLayout(local_layout, 3, vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), &bd->pInputLayout) != S_OK)
+        {
+            vertexShaderBlob->Release();
+            return false;
+        }
+        vertexShaderBlob->Release();
+
+        // Create the constant buffer
+        {
+            D3D10_BUFFER_DESC desc;
+            desc.ByteWidth = sizeof(VERTEX_CONSTANT_BUFFER_DX10);
+            desc.Usage = D3D10_USAGE_DYNAMIC;
+            desc.BindFlags = D3D10_BIND_CONSTANT_BUFFER;
+            desc.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
+            desc.MiscFlags = 0;
+            bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pVertexConstantBuffer);
+        }
+    }
+
+    // Create the pixel shader
+    {
+        static const char* pixelShader =
+            "struct PS_INPUT\
+            {\
+            float4 pos : SV_POSITION;\
+            float4 col : COLOR0;\
+            float2 uv  : TEXCOORD0;\
+            };\
+            sampler sampler0;\
+            Texture2D texture0;\
+            \
+            float4 main(PS_INPUT input) : SV_Target\
+            {\
+            float4 out_col = input.col * texture0.Sample(sampler0, input.uv); \
+            return out_col; \
+            }";
+
+        ID3DBlob* pixelShaderBlob;
+        if (FAILED(D3DCompile(pixelShader, strlen(pixelShader), nullptr, nullptr, nullptr, "main", "ps_4_0", 0, 0, &pixelShaderBlob, nullptr)))
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        if (bd->pd3dDevice->CreatePixelShader(pixelShaderBlob->GetBufferPointer(), pixelShaderBlob->GetBufferSize(), &bd->pPixelShader) != S_OK)
+        {
+            pixelShaderBlob->Release();
+            return false;
+        }
+        pixelShaderBlob->Release();
+    }
+
+    // Create the blending setup
+    {
+        D3D10_BLEND_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.AlphaToCoverageEnable = false;
+        desc.BlendEnable[0] = true;
+        desc.SrcBlend = D3D10_BLEND_SRC_ALPHA;
+        desc.DestBlend = D3D10_BLEND_INV_SRC_ALPHA;
+        desc.BlendOp = D3D10_BLEND_OP_ADD;
+        desc.SrcBlendAlpha = D3D10_BLEND_ONE;
+        desc.DestBlendAlpha = D3D10_BLEND_INV_SRC_ALPHA;
+        desc.BlendOpAlpha = D3D10_BLEND_OP_ADD;
+        desc.RenderTargetWriteMask[0] = D3D10_COLOR_WRITE_ENABLE_ALL;
+        bd->pd3dDevice->CreateBlendState(&desc, &bd->pBlendState);
+    }
+
+    // Create the rasterizer state
+    {
+        D3D10_RASTERIZER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.FillMode = D3D10_FILL_SOLID;
+        desc.CullMode = D3D10_CULL_NONE;
+        desc.ScissorEnable = true;
+        desc.DepthClipEnable = true;
+        bd->pd3dDevice->CreateRasterizerState(&desc, &bd->pRasterizerState);
+    }
+
+    // Create depth-stencil State
+    {
+        D3D10_DEPTH_STENCIL_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.DepthEnable = false;
+        desc.DepthWriteMask = D3D10_DEPTH_WRITE_MASK_ALL;
+        desc.DepthFunc = D3D10_COMPARISON_ALWAYS;
+        desc.StencilEnable = false;
+        desc.FrontFace.StencilFailOp = desc.FrontFace.StencilDepthFailOp = desc.FrontFace.StencilPassOp = D3D10_STENCIL_OP_KEEP;
+        desc.FrontFace.StencilFunc = D3D10_COMPARISON_ALWAYS;
+        desc.BackFace = desc.FrontFace;
+        bd->pd3dDevice->CreateDepthStencilState(&desc, &bd->pDepthStencilState);
+    }
+
+    ImGui_ImplDX10_CreateFontsTexture();
+
+    return true;
+}
+
+void    ImGui_ImplDX10_InvalidateDeviceObjects()
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    if (!bd->pd3dDevice)
+        return;
+
+    if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
+    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
+    if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
+    if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }
+    if (bd->pDepthStencilState)     { bd->pDepthStencilState->Release(); bd->pDepthStencilState = nullptr; }
+    if (bd->pRasterizerState)       { bd->pRasterizerState->Release(); bd->pRasterizerState = nullptr; }
+    if (bd->pPixelShader)           { bd->pPixelShader->Release(); bd->pPixelShader = nullptr; }
+    if (bd->pVertexConstantBuffer)  { bd->pVertexConstantBuffer->Release(); bd->pVertexConstantBuffer = nullptr; }
+    if (bd->pInputLayout)           { bd->pInputLayout->Release(); bd->pInputLayout = nullptr; }
+    if (bd->pVertexShader)          { bd->pVertexShader->Release(); bd->pVertexShader = nullptr; }
+}
+
+bool    ImGui_ImplDX10_Init(ID3D10Device* device)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplDX10_Data* bd = IM_NEW(ImGui_ImplDX10_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_dx10";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    // Get factory from device
+    IDXGIDevice* pDXGIDevice = nullptr;
+    IDXGIAdapter* pDXGIAdapter = nullptr;
+    IDXGIFactory* pFactory = nullptr;
+    if (device->QueryInterface(IID_PPV_ARGS(&pDXGIDevice)) == S_OK)
+        if (pDXGIDevice->GetParent(IID_PPV_ARGS(&pDXGIAdapter)) == S_OK)
+            if (pDXGIAdapter->GetParent(IID_PPV_ARGS(&pFactory)) == S_OK)
+            {
+                bd->pd3dDevice = device;
+                bd->pFactory = pFactory;
+            }
+    if (pDXGIDevice) pDXGIDevice->Release();
+    if (pDXGIAdapter) pDXGIAdapter->Release();
+    bd->pd3dDevice->AddRef();
+
+    return true;
+}
+
+void ImGui_ImplDX10_Shutdown()
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplDX10_InvalidateDeviceObjects();
+    if (bd->pFactory) { bd->pFactory->Release(); }
+    if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+void ImGui_ImplDX10_NewFrame()
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX10_Init()?");
+
+    if (!bd->pFontSampler)
+        ImGui_ImplDX10_CreateDeviceObjects();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx10.h

@@ -0,0 +1,31 @@
+// dear imgui: Renderer Backend for DirectX10
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct ID3D10Device;
+
+IMGUI_IMPL_API bool     ImGui_ImplDX10_Init(ID3D10Device* device);
+IMGUI_IMPL_API void     ImGui_ImplDX10_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplDX10_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API void     ImGui_ImplDX10_InvalidateDeviceObjects();
+IMGUI_IMPL_API bool     ImGui_ImplDX10_CreateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx11.cpp

@@ -0,0 +1,605 @@
+// dear imgui: Renderer Backend for DirectX11
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-05-19: DirectX11: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-02-18: DirectX11: Change blending equation to preserve alpha in output buffer.
+//  2019-08-01: DirectX11: Fixed code querying the Geometry Shader state (would generally error with Debug layer enabled).
+//  2019-07-21: DirectX11: Backup, clear and restore Geometry Shader is any is bound when calling ImGui_ImplDX10_RenderDrawData. Clearing Hull/Domain/Compute shaders without backup/restore.
+//  2019-05-29: DirectX11: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: DirectX11: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2018-12-03: Misc: Added #pragma comment statement to automatically link with d3dcompiler.lib when using D3DCompile().
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-08-01: DirectX11: Querying for IDXGIFactory instead of IDXGIFactory1 to increase compatibility.
+//  2018-07-13: DirectX11: Fixed unreleased resources in Init and Shutdown functions.
+//  2018-06-08: Misc: Extracted imgui_impl_dx11.cpp/.h away from the old combined DX11+Win32 example.
+//  2018-06-08: DirectX11: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX11_RenderDrawData() in the .h file so you can call it yourself.
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2016-05-07: DirectX11: Disabling depth-write.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_dx11.h"
+
+// DirectX
+#include <stdio.h>
+#include <d3d11.h>
+#include <d3dcompiler.h>
+#ifdef _MSC_VER
+#pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
+#endif
+
+// DirectX11 data
+struct ImGui_ImplDX11_Data
+{
+    ID3D11Device*               pd3dDevice;
+    ID3D11DeviceContext*        pd3dDeviceContext;
+    IDXGIFactory*               pFactory;
+    ID3D11Buffer*               pVB;
+    ID3D11Buffer*               pIB;
+    ID3D11VertexShader*         pVertexShader;
+    ID3D11InputLayout*          pInputLayout;
+    ID3D11Buffer*               pVertexConstantBuffer;
+    ID3D11PixelShader*          pPixelShader;
+    ID3D11SamplerState*         pFontSampler;
+    ID3D11ShaderResourceView*   pFontTextureView;
+    ID3D11RasterizerState*      pRasterizerState;
+    ID3D11BlendState*           pBlendState;
+    ID3D11DepthStencilState*    pDepthStencilState;
+    int                         VertexBufferSize;
+    int                         IndexBufferSize;
+
+    ImGui_ImplDX11_Data()       { memset((void*)this, 0, sizeof(*this)); VertexBufferSize = 5000; IndexBufferSize = 10000; }
+};
+
+struct VERTEX_CONSTANT_BUFFER_DX11
+{
+    float   mvp[4][4];
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplDX11_Data* ImGui_ImplDX11_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplDX11_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+static void ImGui_ImplDX11_SetupRenderState(ImDrawData* draw_data, ID3D11DeviceContext* ctx)
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+
+    // Setup viewport
+    D3D11_VIEWPORT vp;
+    memset(&vp, 0, sizeof(D3D11_VIEWPORT));
+    vp.Width = draw_data->DisplaySize.x;
+    vp.Height = draw_data->DisplaySize.y;
+    vp.MinDepth = 0.0f;
+    vp.MaxDepth = 1.0f;
+    vp.TopLeftX = vp.TopLeftY = 0;
+    ctx->RSSetViewports(1, &vp);
+
+    // Setup shader and vertex buffers
+    unsigned int stride = sizeof(ImDrawVert);
+    unsigned int offset = 0;
+    ctx->IASetInputLayout(bd->pInputLayout);
+    ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
+    ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
+    ctx->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    ctx->VSSetShader(bd->pVertexShader, nullptr, 0);
+    ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
+    ctx->PSSetShader(bd->pPixelShader, nullptr, 0);
+    ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
+    ctx->GSSetShader(nullptr, nullptr, 0);
+    ctx->HSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+    ctx->DSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+    ctx->CSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+
+    // Setup blend state
+    const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
+    ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
+    ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
+    ctx->RSSetState(bd->pRasterizerState);
+}
+
+// Render function
+void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    ID3D11DeviceContext* ctx = bd->pd3dDeviceContext;
+
+    // Create and grow vertex/index buffers if needed
+    if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
+    {
+        if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
+        bd->VertexBufferSize = draw_data->TotalVtxCount + 5000;
+        D3D11_BUFFER_DESC desc;
+        memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
+        desc.Usage = D3D11_USAGE_DYNAMIC;
+        desc.ByteWidth = bd->VertexBufferSize * sizeof(ImDrawVert);
+        desc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
+        desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
+        desc.MiscFlags = 0;
+        if (bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pVB) < 0)
+            return;
+    }
+    if (!bd->pIB || bd->IndexBufferSize < draw_data->TotalIdxCount)
+    {
+        if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
+        bd->IndexBufferSize = draw_data->TotalIdxCount + 10000;
+        D3D11_BUFFER_DESC desc;
+        memset(&desc, 0, sizeof(D3D11_BUFFER_DESC));
+        desc.Usage = D3D11_USAGE_DYNAMIC;
+        desc.ByteWidth = bd->IndexBufferSize * sizeof(ImDrawIdx);
+        desc.BindFlags = D3D11_BIND_INDEX_BUFFER;
+        desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
+        if (bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pIB) < 0)
+            return;
+    }
+
+    // Upload vertex/index data into a single contiguous GPU buffer
+    D3D11_MAPPED_SUBRESOURCE vtx_resource, idx_resource;
+    if (ctx->Map(bd->pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &vtx_resource) != S_OK)
+        return;
+    if (ctx->Map(bd->pIB, 0, D3D11_MAP_WRITE_DISCARD, 0, &idx_resource) != S_OK)
+        return;
+    ImDrawVert* vtx_dst = (ImDrawVert*)vtx_resource.pData;
+    ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource.pData;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += cmd_list->VtxBuffer.Size;
+        idx_dst += cmd_list->IdxBuffer.Size;
+    }
+    ctx->Unmap(bd->pVB, 0);
+    ctx->Unmap(bd->pIB, 0);
+
+    // Setup orthographic projection matrix into our constant buffer
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
+    {
+        D3D11_MAPPED_SUBRESOURCE mapped_resource;
+        if (ctx->Map(bd->pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
+            return;
+        VERTEX_CONSTANT_BUFFER_DX11* constant_buffer = (VERTEX_CONSTANT_BUFFER_DX11*)mapped_resource.pData;
+        float L = draw_data->DisplayPos.x;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+        float T = draw_data->DisplayPos.y;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+        float mvp[4][4] =
+        {
+            { 2.0f/(R-L),   0.0f,           0.0f,       0.0f },
+            { 0.0f,         2.0f/(T-B),     0.0f,       0.0f },
+            { 0.0f,         0.0f,           0.5f,       0.0f },
+            { (R+L)/(L-R),  (T+B)/(B-T),    0.5f,       1.0f },
+        };
+        memcpy(&constant_buffer->mvp, mvp, sizeof(mvp));
+        ctx->Unmap(bd->pVertexConstantBuffer, 0);
+    }
+
+    // Backup DX state that will be modified to restore it afterwards (unfortunately this is very ugly looking and verbose. Close your eyes!)
+    struct BACKUP_DX11_STATE
+    {
+        UINT                        ScissorRectsCount, ViewportsCount;
+        D3D11_RECT                  ScissorRects[D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
+        D3D11_VIEWPORT              Viewports[D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE];
+        ID3D11RasterizerState*      RS;
+        ID3D11BlendState*           BlendState;
+        FLOAT                       BlendFactor[4];
+        UINT                        SampleMask;
+        UINT                        StencilRef;
+        ID3D11DepthStencilState*    DepthStencilState;
+        ID3D11ShaderResourceView*   PSShaderResource;
+        ID3D11SamplerState*         PSSampler;
+        ID3D11PixelShader*          PS;
+        ID3D11VertexShader*         VS;
+        ID3D11GeometryShader*       GS;
+        UINT                        PSInstancesCount, VSInstancesCount, GSInstancesCount;
+        ID3D11ClassInstance         *PSInstances[256], *VSInstances[256], *GSInstances[256];   // 256 is max according to PSSetShader documentation
+        D3D11_PRIMITIVE_TOPOLOGY    PrimitiveTopology;
+        ID3D11Buffer*               IndexBuffer, *VertexBuffer, *VSConstantBuffer;
+        UINT                        IndexBufferOffset, VertexBufferStride, VertexBufferOffset;
+        DXGI_FORMAT                 IndexBufferFormat;
+        ID3D11InputLayout*          InputLayout;
+    };
+    BACKUP_DX11_STATE old = {};
+    old.ScissorRectsCount = old.ViewportsCount = D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE;
+    ctx->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
+    ctx->RSGetViewports(&old.ViewportsCount, old.Viewports);
+    ctx->RSGetState(&old.RS);
+    ctx->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
+    ctx->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
+    ctx->PSGetShaderResources(0, 1, &old.PSShaderResource);
+    ctx->PSGetSamplers(0, 1, &old.PSSampler);
+    old.PSInstancesCount = old.VSInstancesCount = old.GSInstancesCount = 256;
+    ctx->PSGetShader(&old.PS, old.PSInstances, &old.PSInstancesCount);
+    ctx->VSGetShader(&old.VS, old.VSInstances, &old.VSInstancesCount);
+    ctx->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
+    ctx->GSGetShader(&old.GS, old.GSInstances, &old.GSInstancesCount);
+
+    ctx->IAGetPrimitiveTopology(&old.PrimitiveTopology);
+    ctx->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
+    ctx->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
+    ctx->IAGetInputLayout(&old.InputLayout);
+
+    // Setup desired DX state
+    ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
+
+    // Render command lists
+    // (Because we merged all buffers into a single one, we maintain our own offset into them)
+    int global_idx_offset = 0;
+    int global_vtx_offset = 0;
+    ImVec2 clip_off = draw_data->DisplayPos;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback != nullptr)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+                ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle
+                const D3D11_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                ctx->RSSetScissorRects(1, &r);
+
+                // Bind texture, Draw
+                ID3D11ShaderResourceView* texture_srv = (ID3D11ShaderResourceView*)pcmd->GetTexID();
+                ctx->PSSetShaderResources(0, 1, &texture_srv);
+                ctx->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
+            }
+        }
+        global_idx_offset += cmd_list->IdxBuffer.Size;
+        global_vtx_offset += cmd_list->VtxBuffer.Size;
+    }
+
+    // Restore modified DX state
+    ctx->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
+    ctx->RSSetViewports(old.ViewportsCount, old.Viewports);
+    ctx->RSSetState(old.RS); if (old.RS) old.RS->Release();
+    ctx->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
+    ctx->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
+    ctx->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
+    ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
+    ctx->PSSetShader(old.PS, old.PSInstances, old.PSInstancesCount); if (old.PS) old.PS->Release();
+    for (UINT i = 0; i < old.PSInstancesCount; i++) if (old.PSInstances[i]) old.PSInstances[i]->Release();
+    ctx->VSSetShader(old.VS, old.VSInstances, old.VSInstancesCount); if (old.VS) old.VS->Release();
+    ctx->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
+    ctx->GSSetShader(old.GS, old.GSInstances, old.GSInstancesCount); if (old.GS) old.GS->Release();
+    for (UINT i = 0; i < old.VSInstancesCount; i++) if (old.VSInstances[i]) old.VSInstances[i]->Release();
+    ctx->IASetPrimitiveTopology(old.PrimitiveTopology);
+    ctx->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
+    ctx->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
+    ctx->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
+}
+
+static void ImGui_ImplDX11_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
+
+    // Upload texture to graphics system
+    {
+        D3D11_TEXTURE2D_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Width = width;
+        desc.Height = height;
+        desc.MipLevels = 1;
+        desc.ArraySize = 1;
+        desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        desc.SampleDesc.Count = 1;
+        desc.Usage = D3D11_USAGE_DEFAULT;
+        desc.BindFlags = D3D11_BIND_SHADER_RESOURCE;
+        desc.CPUAccessFlags = 0;
+
+        ID3D11Texture2D* pTexture = nullptr;
+        D3D11_SUBRESOURCE_DATA subResource;
+        subResource.pSysMem = pixels;
+        subResource.SysMemPitch = desc.Width * 4;
+        subResource.SysMemSlicePitch = 0;
+        bd->pd3dDevice->CreateTexture2D(&desc, &subResource, &pTexture);
+        IM_ASSERT(pTexture != nullptr);
+
+        // Create texture view
+        D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc;
+        ZeroMemory(&srvDesc, sizeof(srvDesc));
+        srvDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        srvDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
+        srvDesc.Texture2D.MipLevels = desc.MipLevels;
+        srvDesc.Texture2D.MostDetailedMip = 0;
+        bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, &bd->pFontTextureView);
+        pTexture->Release();
+    }
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)bd->pFontTextureView);
+
+    // Create texture sampler
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    {
+        D3D11_SAMPLER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
+        desc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
+        desc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
+        desc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
+        desc.MipLODBias = 0.f;
+        desc.ComparisonFunc = D3D11_COMPARISON_ALWAYS;
+        desc.MinLOD = 0.f;
+        desc.MaxLOD = 0.f;
+        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+    }
+}
+
+bool    ImGui_ImplDX11_CreateDeviceObjects()
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    if (!bd->pd3dDevice)
+        return false;
+    if (bd->pFontSampler)
+        ImGui_ImplDX11_InvalidateDeviceObjects();
+
+    // By using D3DCompile() from <d3dcompiler.h> / d3dcompiler.lib, we introduce a dependency to a given version of d3dcompiler_XX.dll (see D3DCOMPILER_DLL_A)
+    // If you would like to use this DX11 sample code but remove this dependency you can:
+    //  1) compile once, save the compiled shader blobs into a file or source code and pass them to CreateVertexShader()/CreatePixelShader() [preferred solution]
+    //  2) use code to detect any version of the DLL and grab a pointer to D3DCompile from the DLL.
+    // See https://github.com/ocornut/imgui/pull/638 for sources and details.
+
+    // Create the vertex shader
+    {
+        static const char* vertexShader =
+            "cbuffer vertexBuffer : register(b0) \
+            {\
+              float4x4 ProjectionMatrix; \
+            };\
+            struct VS_INPUT\
+            {\
+              float2 pos : POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            struct PS_INPUT\
+            {\
+              float4 pos : SV_POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            PS_INPUT main(VS_INPUT input)\
+            {\
+              PS_INPUT output;\
+              output.pos = mul( ProjectionMatrix, float4(input.pos.xy, 0.f, 1.f));\
+              output.col = input.col;\
+              output.uv  = input.uv;\
+              return output;\
+            }";
+
+        ID3DBlob* vertexShaderBlob;
+        if (FAILED(D3DCompile(vertexShader, strlen(vertexShader), nullptr, nullptr, nullptr, "main", "vs_4_0", 0, 0, &vertexShaderBlob, nullptr)))
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        if (bd->pd3dDevice->CreateVertexShader(vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), nullptr, &bd->pVertexShader) != S_OK)
+        {
+            vertexShaderBlob->Release();
+            return false;
+        }
+
+        // Create the input layout
+        D3D11_INPUT_ELEMENT_DESC local_layout[] =
+        {
+            { "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, pos), D3D11_INPUT_PER_VERTEX_DATA, 0 },
+            { "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, uv),  D3D11_INPUT_PER_VERTEX_DATA, 0 },
+            { "COLOR",    0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (UINT)IM_OFFSETOF(ImDrawVert, col), D3D11_INPUT_PER_VERTEX_DATA, 0 },
+        };
+        if (bd->pd3dDevice->CreateInputLayout(local_layout, 3, vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize(), &bd->pInputLayout) != S_OK)
+        {
+            vertexShaderBlob->Release();
+            return false;
+        }
+        vertexShaderBlob->Release();
+
+        // Create the constant buffer
+        {
+            D3D11_BUFFER_DESC desc;
+            desc.ByteWidth = sizeof(VERTEX_CONSTANT_BUFFER_DX11);
+            desc.Usage = D3D11_USAGE_DYNAMIC;
+            desc.BindFlags = D3D11_BIND_CONSTANT_BUFFER;
+            desc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
+            desc.MiscFlags = 0;
+            bd->pd3dDevice->CreateBuffer(&desc, nullptr, &bd->pVertexConstantBuffer);
+        }
+    }
+
+    // Create the pixel shader
+    {
+        static const char* pixelShader =
+            "struct PS_INPUT\
+            {\
+            float4 pos : SV_POSITION;\
+            float4 col : COLOR0;\
+            float2 uv  : TEXCOORD0;\
+            };\
+            sampler sampler0;\
+            Texture2D texture0;\
+            \
+            float4 main(PS_INPUT input) : SV_Target\
+            {\
+            float4 out_col = input.col * texture0.Sample(sampler0, input.uv); \
+            return out_col; \
+            }";
+
+        ID3DBlob* pixelShaderBlob;
+        if (FAILED(D3DCompile(pixelShader, strlen(pixelShader), nullptr, nullptr, nullptr, "main", "ps_4_0", 0, 0, &pixelShaderBlob, nullptr)))
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        if (bd->pd3dDevice->CreatePixelShader(pixelShaderBlob->GetBufferPointer(), pixelShaderBlob->GetBufferSize(), nullptr, &bd->pPixelShader) != S_OK)
+        {
+            pixelShaderBlob->Release();
+            return false;
+        }
+        pixelShaderBlob->Release();
+    }
+
+    // Create the blending setup
+    {
+        D3D11_BLEND_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.AlphaToCoverageEnable = false;
+        desc.RenderTarget[0].BlendEnable = true;
+        desc.RenderTarget[0].SrcBlend = D3D11_BLEND_SRC_ALPHA;
+        desc.RenderTarget[0].DestBlend = D3D11_BLEND_INV_SRC_ALPHA;
+        desc.RenderTarget[0].BlendOp = D3D11_BLEND_OP_ADD;
+        desc.RenderTarget[0].SrcBlendAlpha = D3D11_BLEND_ONE;
+        desc.RenderTarget[0].DestBlendAlpha = D3D11_BLEND_INV_SRC_ALPHA;
+        desc.RenderTarget[0].BlendOpAlpha = D3D11_BLEND_OP_ADD;
+        desc.RenderTarget[0].RenderTargetWriteMask = D3D11_COLOR_WRITE_ENABLE_ALL;
+        bd->pd3dDevice->CreateBlendState(&desc, &bd->pBlendState);
+    }
+
+    // Create the rasterizer state
+    {
+        D3D11_RASTERIZER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.FillMode = D3D11_FILL_SOLID;
+        desc.CullMode = D3D11_CULL_NONE;
+        desc.ScissorEnable = true;
+        desc.DepthClipEnable = true;
+        bd->pd3dDevice->CreateRasterizerState(&desc, &bd->pRasterizerState);
+    }
+
+    // Create depth-stencil State
+    {
+        D3D11_DEPTH_STENCIL_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.DepthEnable = false;
+        desc.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ALL;
+        desc.DepthFunc = D3D11_COMPARISON_ALWAYS;
+        desc.StencilEnable = false;
+        desc.FrontFace.StencilFailOp = desc.FrontFace.StencilDepthFailOp = desc.FrontFace.StencilPassOp = D3D11_STENCIL_OP_KEEP;
+        desc.FrontFace.StencilFunc = D3D11_COMPARISON_ALWAYS;
+        desc.BackFace = desc.FrontFace;
+        bd->pd3dDevice->CreateDepthStencilState(&desc, &bd->pDepthStencilState);
+    }
+
+    ImGui_ImplDX11_CreateFontsTexture();
+
+    return true;
+}
+
+void    ImGui_ImplDX11_InvalidateDeviceObjects()
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    if (!bd->pd3dDevice)
+        return;
+
+    if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
+    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
+    if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
+    if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }
+    if (bd->pDepthStencilState)     { bd->pDepthStencilState->Release(); bd->pDepthStencilState = nullptr; }
+    if (bd->pRasterizerState)       { bd->pRasterizerState->Release(); bd->pRasterizerState = nullptr; }
+    if (bd->pPixelShader)           { bd->pPixelShader->Release(); bd->pPixelShader = nullptr; }
+    if (bd->pVertexConstantBuffer)  { bd->pVertexConstantBuffer->Release(); bd->pVertexConstantBuffer = nullptr; }
+    if (bd->pInputLayout)           { bd->pInputLayout->Release(); bd->pInputLayout = nullptr; }
+    if (bd->pVertexShader)          { bd->pVertexShader->Release(); bd->pVertexShader = nullptr; }
+}
+
+bool    ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_context)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplDX11_Data* bd = IM_NEW(ImGui_ImplDX11_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_dx11";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    // Get factory from device
+    IDXGIDevice* pDXGIDevice = nullptr;
+    IDXGIAdapter* pDXGIAdapter = nullptr;
+    IDXGIFactory* pFactory = nullptr;
+
+    if (device->QueryInterface(IID_PPV_ARGS(&pDXGIDevice)) == S_OK)
+        if (pDXGIDevice->GetParent(IID_PPV_ARGS(&pDXGIAdapter)) == S_OK)
+            if (pDXGIAdapter->GetParent(IID_PPV_ARGS(&pFactory)) == S_OK)
+            {
+                bd->pd3dDevice = device;
+                bd->pd3dDeviceContext = device_context;
+                bd->pFactory = pFactory;
+            }
+    if (pDXGIDevice) pDXGIDevice->Release();
+    if (pDXGIAdapter) pDXGIAdapter->Release();
+    bd->pd3dDevice->AddRef();
+    bd->pd3dDeviceContext->AddRef();
+
+    return true;
+}
+
+void ImGui_ImplDX11_Shutdown()
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplDX11_InvalidateDeviceObjects();
+    if (bd->pFactory)             { bd->pFactory->Release(); }
+    if (bd->pd3dDevice)           { bd->pd3dDevice->Release(); }
+    if (bd->pd3dDeviceContext)    { bd->pd3dDeviceContext->Release(); }
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+void ImGui_ImplDX11_NewFrame()
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX11_Init()?");
+
+    if (!bd->pFontSampler)
+        ImGui_ImplDX11_CreateDeviceObjects();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx11.h

@@ -0,0 +1,32 @@
+// dear imgui: Renderer Backend for DirectX11
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct ID3D11Device;
+struct ID3D11DeviceContext;
+
+IMGUI_IMPL_API bool     ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_context);
+IMGUI_IMPL_API void     ImGui_ImplDX11_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplDX11_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API void     ImGui_ImplDX11_InvalidateDeviceObjects();
+IMGUI_IMPL_API bool     ImGui_ImplDX11_CreateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx12.cpp

@@ -0,0 +1,761 @@
+// dear imgui: Renderer Backend for DirectX12
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
+// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
+// To build this on 32-bit systems:
+// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
+// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
+// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
+// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-05-19: DirectX12: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-02-18: DirectX12: Change blending equation to preserve alpha in output buffer.
+//  2021-01-11: DirectX12: Improve Windows 7 compatibility (for D3D12On7) by loading d3d12.dll dynamically.
+//  2020-09-16: DirectX12: Avoid rendering calls with zero-sized scissor rectangle since it generates a validation layer warning.
+//  2020-09-08: DirectX12: Clarified support for building on 32-bit systems by redefining ImTextureID.
+//  2019-10-18: DirectX12: *BREAKING CHANGE* Added extra ID3D12DescriptorHeap parameter to ImGui_ImplDX12_Init() function.
+//  2019-05-29: DirectX12: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: DirectX12: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2019-03-29: Misc: Various minor tidying up.
+//  2018-12-03: Misc: Added #pragma comment statement to automatically link with d3dcompiler.lib when using D3DCompile().
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-06-12: DirectX12: Moved the ID3D12GraphicsCommandList* parameter from NewFrame() to RenderDrawData().
+//  2018-06-08: Misc: Extracted imgui_impl_dx12.cpp/.h away from the old combined DX12+Win32 example.
+//  2018-06-08: DirectX12: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle (to ease support for future multi-viewport).
+//  2018-02-22: Merged into master with all Win32 code synchronized to other examples.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_dx12.h"
+
+// DirectX
+#include <d3d12.h>
+#include <dxgi1_4.h>
+#include <d3dcompiler.h>
+#ifdef _MSC_VER
+#pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
+#endif
+
+// DirectX data
+struct ImGui_ImplDX12_RenderBuffers;
+struct ImGui_ImplDX12_Data
+{
+    ID3D12Device*               pd3dDevice;
+    ID3D12RootSignature*        pRootSignature;
+    ID3D12PipelineState*        pPipelineState;
+    DXGI_FORMAT                 RTVFormat;
+    ID3D12Resource*             pFontTextureResource;
+    D3D12_CPU_DESCRIPTOR_HANDLE hFontSrvCpuDescHandle;
+    D3D12_GPU_DESCRIPTOR_HANDLE hFontSrvGpuDescHandle;
+    ID3D12DescriptorHeap*       pd3dSrvDescHeap;
+    UINT                        numFramesInFlight;
+
+    ImGui_ImplDX12_RenderBuffers* pFrameResources;
+    UINT                        frameIndex;
+
+    ImGui_ImplDX12_Data()       { memset((void*)this, 0, sizeof(*this)); frameIndex = UINT_MAX; }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplDX12_Data* ImGui_ImplDX12_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplDX12_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Buffers used during the rendering of a frame
+struct ImGui_ImplDX12_RenderBuffers
+{
+    ID3D12Resource*     IndexBuffer;
+    ID3D12Resource*     VertexBuffer;
+    int                 IndexBufferSize;
+    int                 VertexBufferSize;
+};
+
+struct VERTEX_CONSTANT_BUFFER_DX12
+{
+    float   mvp[4][4];
+};
+
+// Functions
+static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx, ImGui_ImplDX12_RenderBuffers* fr)
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+
+    // Setup orthographic projection matrix into our constant buffer
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
+    VERTEX_CONSTANT_BUFFER_DX12 vertex_constant_buffer;
+    {
+        float L = draw_data->DisplayPos.x;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+        float T = draw_data->DisplayPos.y;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+        float mvp[4][4] =
+        {
+            { 2.0f/(R-L),   0.0f,           0.0f,       0.0f },
+            { 0.0f,         2.0f/(T-B),     0.0f,       0.0f },
+            { 0.0f,         0.0f,           0.5f,       0.0f },
+            { (R+L)/(L-R),  (T+B)/(B-T),    0.5f,       1.0f },
+        };
+        memcpy(&vertex_constant_buffer.mvp, mvp, sizeof(mvp));
+    }
+
+    // Setup viewport
+    D3D12_VIEWPORT vp;
+    memset(&vp, 0, sizeof(D3D12_VIEWPORT));
+    vp.Width = draw_data->DisplaySize.x;
+    vp.Height = draw_data->DisplaySize.y;
+    vp.MinDepth = 0.0f;
+    vp.MaxDepth = 1.0f;
+    vp.TopLeftX = vp.TopLeftY = 0.0f;
+    ctx->RSSetViewports(1, &vp);
+
+    // Bind shader and vertex buffers
+    unsigned int stride = sizeof(ImDrawVert);
+    unsigned int offset = 0;
+    D3D12_VERTEX_BUFFER_VIEW vbv;
+    memset(&vbv, 0, sizeof(D3D12_VERTEX_BUFFER_VIEW));
+    vbv.BufferLocation = fr->VertexBuffer->GetGPUVirtualAddress() + offset;
+    vbv.SizeInBytes = fr->VertexBufferSize * stride;
+    vbv.StrideInBytes = stride;
+    ctx->IASetVertexBuffers(0, 1, &vbv);
+    D3D12_INDEX_BUFFER_VIEW ibv;
+    memset(&ibv, 0, sizeof(D3D12_INDEX_BUFFER_VIEW));
+    ibv.BufferLocation = fr->IndexBuffer->GetGPUVirtualAddress();
+    ibv.SizeInBytes = fr->IndexBufferSize * sizeof(ImDrawIdx);
+    ibv.Format = sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT;
+    ctx->IASetIndexBuffer(&ibv);
+    ctx->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    ctx->SetPipelineState(bd->pPipelineState);
+    ctx->SetGraphicsRootSignature(bd->pRootSignature);
+    ctx->SetGraphicsRoot32BitConstants(0, 16, &vertex_constant_buffer, 0);
+
+    // Setup blend factor
+    const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
+    ctx->OMSetBlendFactor(blend_factor);
+}
+
+template<typename T>
+static inline void SafeRelease(T*& res)
+{
+    if (res)
+        res->Release();
+    res = nullptr;
+}
+
+// Render function
+void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    // FIXME: I'm assuming that this only gets called once per frame!
+    // If not, we can't just re-allocate the IB or VB, we'll have to do a proper allocator.
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    bd->frameIndex = bd->frameIndex + 1;
+    ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[bd->frameIndex % bd->numFramesInFlight];
+
+    // Create and grow vertex/index buffers if needed
+    if (fr->VertexBuffer == nullptr || fr->VertexBufferSize < draw_data->TotalVtxCount)
+    {
+        SafeRelease(fr->VertexBuffer);
+        fr->VertexBufferSize = draw_data->TotalVtxCount + 5000;
+        D3D12_HEAP_PROPERTIES props;
+        memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
+        props.Type = D3D12_HEAP_TYPE_UPLOAD;
+        props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
+        props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
+        D3D12_RESOURCE_DESC desc;
+        memset(&desc, 0, sizeof(D3D12_RESOURCE_DESC));
+        desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
+        desc.Width = fr->VertexBufferSize * sizeof(ImDrawVert);
+        desc.Height = 1;
+        desc.DepthOrArraySize = 1;
+        desc.MipLevels = 1;
+        desc.Format = DXGI_FORMAT_UNKNOWN;
+        desc.SampleDesc.Count = 1;
+        desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
+        desc.Flags = D3D12_RESOURCE_FLAG_NONE;
+        if (bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc, D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&fr->VertexBuffer)) < 0)
+            return;
+    }
+    if (fr->IndexBuffer == nullptr || fr->IndexBufferSize < draw_data->TotalIdxCount)
+    {
+        SafeRelease(fr->IndexBuffer);
+        fr->IndexBufferSize = draw_data->TotalIdxCount + 10000;
+        D3D12_HEAP_PROPERTIES props;
+        memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
+        props.Type = D3D12_HEAP_TYPE_UPLOAD;
+        props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
+        props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
+        D3D12_RESOURCE_DESC desc;
+        memset(&desc, 0, sizeof(D3D12_RESOURCE_DESC));
+        desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
+        desc.Width = fr->IndexBufferSize * sizeof(ImDrawIdx);
+        desc.Height = 1;
+        desc.DepthOrArraySize = 1;
+        desc.MipLevels = 1;
+        desc.Format = DXGI_FORMAT_UNKNOWN;
+        desc.SampleDesc.Count = 1;
+        desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
+        desc.Flags = D3D12_RESOURCE_FLAG_NONE;
+        if (bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc, D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&fr->IndexBuffer)) < 0)
+            return;
+    }
+
+    // Upload vertex/index data into a single contiguous GPU buffer
+    void* vtx_resource, *idx_resource;
+    D3D12_RANGE range;
+    memset(&range, 0, sizeof(D3D12_RANGE));
+    if (fr->VertexBuffer->Map(0, &range, &vtx_resource) != S_OK)
+        return;
+    if (fr->IndexBuffer->Map(0, &range, &idx_resource) != S_OK)
+        return;
+    ImDrawVert* vtx_dst = (ImDrawVert*)vtx_resource;
+    ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += cmd_list->VtxBuffer.Size;
+        idx_dst += cmd_list->IdxBuffer.Size;
+    }
+    fr->VertexBuffer->Unmap(0, &range);
+    fr->IndexBuffer->Unmap(0, &range);
+
+    // Setup desired DX state
+    ImGui_ImplDX12_SetupRenderState(draw_data, ctx, fr);
+
+    // Render command lists
+    // (Because we merged all buffers into a single one, we maintain our own offset into them)
+    int global_vtx_offset = 0;
+    int global_idx_offset = 0;
+    ImVec2 clip_off = draw_data->DisplayPos;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback != nullptr)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplDX12_SetupRenderState(draw_data, ctx, fr);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+                ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply Scissor/clipping rectangle, Bind texture, Draw
+                const D3D12_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                D3D12_GPU_DESCRIPTOR_HANDLE texture_handle = {};
+                texture_handle.ptr = (UINT64)pcmd->GetTexID();
+                ctx->SetGraphicsRootDescriptorTable(1, texture_handle);
+                ctx->RSSetScissorRects(1, &r);
+                ctx->DrawIndexedInstanced(pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
+            }
+        }
+        global_idx_offset += cmd_list->IdxBuffer.Size;
+        global_vtx_offset += cmd_list->VtxBuffer.Size;
+    }
+}
+
+static void ImGui_ImplDX12_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
+
+    // Upload texture to graphics system
+    {
+        D3D12_HEAP_PROPERTIES props;
+        memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
+        props.Type = D3D12_HEAP_TYPE_DEFAULT;
+        props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
+        props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
+
+        D3D12_RESOURCE_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Dimension = D3D12_RESOURCE_DIMENSION_TEXTURE2D;
+        desc.Alignment = 0;
+        desc.Width = width;
+        desc.Height = height;
+        desc.DepthOrArraySize = 1;
+        desc.MipLevels = 1;
+        desc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        desc.SampleDesc.Count = 1;
+        desc.SampleDesc.Quality = 0;
+        desc.Layout = D3D12_TEXTURE_LAYOUT_UNKNOWN;
+        desc.Flags = D3D12_RESOURCE_FLAG_NONE;
+
+        ID3D12Resource* pTexture = nullptr;
+        bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc,
+            D3D12_RESOURCE_STATE_COPY_DEST, nullptr, IID_PPV_ARGS(&pTexture));
+
+        UINT uploadPitch = (width * 4 + D3D12_TEXTURE_DATA_PITCH_ALIGNMENT - 1u) & ~(D3D12_TEXTURE_DATA_PITCH_ALIGNMENT - 1u);
+        UINT uploadSize = height * uploadPitch;
+        desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
+        desc.Alignment = 0;
+        desc.Width = uploadSize;
+        desc.Height = 1;
+        desc.DepthOrArraySize = 1;
+        desc.MipLevels = 1;
+        desc.Format = DXGI_FORMAT_UNKNOWN;
+        desc.SampleDesc.Count = 1;
+        desc.SampleDesc.Quality = 0;
+        desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
+        desc.Flags = D3D12_RESOURCE_FLAG_NONE;
+
+        props.Type = D3D12_HEAP_TYPE_UPLOAD;
+        props.CPUPageProperty = D3D12_CPU_PAGE_PROPERTY_UNKNOWN;
+        props.MemoryPoolPreference = D3D12_MEMORY_POOL_UNKNOWN;
+
+        ID3D12Resource* uploadBuffer = nullptr;
+        HRESULT hr = bd->pd3dDevice->CreateCommittedResource(&props, D3D12_HEAP_FLAG_NONE, &desc,
+            D3D12_RESOURCE_STATE_GENERIC_READ, nullptr, IID_PPV_ARGS(&uploadBuffer));
+        IM_ASSERT(SUCCEEDED(hr));
+
+        void* mapped = nullptr;
+        D3D12_RANGE range = { 0, uploadSize };
+        hr = uploadBuffer->Map(0, &range, &mapped);
+        IM_ASSERT(SUCCEEDED(hr));
+        for (int y = 0; y < height; y++)
+            memcpy((void*) ((uintptr_t) mapped + y * uploadPitch), pixels + y * width * 4, width * 4);
+        uploadBuffer->Unmap(0, &range);
+
+        D3D12_TEXTURE_COPY_LOCATION srcLocation = {};
+        srcLocation.pResource = uploadBuffer;
+        srcLocation.Type = D3D12_TEXTURE_COPY_TYPE_PLACED_FOOTPRINT;
+        srcLocation.PlacedFootprint.Footprint.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        srcLocation.PlacedFootprint.Footprint.Width = width;
+        srcLocation.PlacedFootprint.Footprint.Height = height;
+        srcLocation.PlacedFootprint.Footprint.Depth = 1;
+        srcLocation.PlacedFootprint.Footprint.RowPitch = uploadPitch;
+
+        D3D12_TEXTURE_COPY_LOCATION dstLocation = {};
+        dstLocation.pResource = pTexture;
+        dstLocation.Type = D3D12_TEXTURE_COPY_TYPE_SUBRESOURCE_INDEX;
+        dstLocation.SubresourceIndex = 0;
+
+        D3D12_RESOURCE_BARRIER barrier = {};
+        barrier.Type = D3D12_RESOURCE_BARRIER_TYPE_TRANSITION;
+        barrier.Flags = D3D12_RESOURCE_BARRIER_FLAG_NONE;
+        barrier.Transition.pResource   = pTexture;
+        barrier.Transition.Subresource = D3D12_RESOURCE_BARRIER_ALL_SUBRESOURCES;
+        barrier.Transition.StateBefore = D3D12_RESOURCE_STATE_COPY_DEST;
+        barrier.Transition.StateAfter  = D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE;
+
+        ID3D12Fence* fence = nullptr;
+        hr = bd->pd3dDevice->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&fence));
+        IM_ASSERT(SUCCEEDED(hr));
+
+        HANDLE event = CreateEvent(0, 0, 0, 0);
+        IM_ASSERT(event != nullptr);
+
+        D3D12_COMMAND_QUEUE_DESC queueDesc = {};
+        queueDesc.Type     = D3D12_COMMAND_LIST_TYPE_DIRECT;
+        queueDesc.Flags    = D3D12_COMMAND_QUEUE_FLAG_NONE;
+        queueDesc.NodeMask = 1;
+
+        ID3D12CommandQueue* cmdQueue = nullptr;
+        hr = bd->pd3dDevice->CreateCommandQueue(&queueDesc, IID_PPV_ARGS(&cmdQueue));
+        IM_ASSERT(SUCCEEDED(hr));
+
+        ID3D12CommandAllocator* cmdAlloc = nullptr;
+        hr = bd->pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&cmdAlloc));
+        IM_ASSERT(SUCCEEDED(hr));
+
+        ID3D12GraphicsCommandList* cmdList = nullptr;
+        hr = bd->pd3dDevice->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, cmdAlloc, nullptr, IID_PPV_ARGS(&cmdList));
+        IM_ASSERT(SUCCEEDED(hr));
+
+        cmdList->CopyTextureRegion(&dstLocation, 0, 0, 0, &srcLocation, nullptr);
+        cmdList->ResourceBarrier(1, &barrier);
+
+        hr = cmdList->Close();
+        IM_ASSERT(SUCCEEDED(hr));
+
+        cmdQueue->ExecuteCommandLists(1, (ID3D12CommandList* const*)&cmdList);
+        hr = cmdQueue->Signal(fence, 1);
+        IM_ASSERT(SUCCEEDED(hr));
+
+        fence->SetEventOnCompletion(1, event);
+        WaitForSingleObject(event, INFINITE);
+
+        cmdList->Release();
+        cmdAlloc->Release();
+        cmdQueue->Release();
+        CloseHandle(event);
+        fence->Release();
+        uploadBuffer->Release();
+
+        // Create texture view
+        D3D12_SHADER_RESOURCE_VIEW_DESC srvDesc;
+        ZeroMemory(&srvDesc, sizeof(srvDesc));
+        srvDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+        srvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2D;
+        srvDesc.Texture2D.MipLevels = desc.MipLevels;
+        srvDesc.Texture2D.MostDetailedMip = 0;
+        srvDesc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;
+        bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, bd->hFontSrvCpuDescHandle);
+        SafeRelease(bd->pFontTextureResource);
+        bd->pFontTextureResource = pTexture;
+    }
+
+    // Store our identifier
+    // READ THIS IF THE STATIC_ASSERT() TRIGGERS:
+    // - Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
+    // - This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
+    // [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
+    // [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
+    // [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
+    // [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
+    static_assert(sizeof(ImTextureID) >= sizeof(bd->hFontSrvGpuDescHandle.ptr), "Can't pack descriptor handle into TexID, 32-bit not supported yet.");
+    io.Fonts->SetTexID((ImTextureID)bd->hFontSrvGpuDescHandle.ptr);
+}
+
+bool    ImGui_ImplDX12_CreateDeviceObjects()
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    if (!bd || !bd->pd3dDevice)
+        return false;
+    if (bd->pPipelineState)
+        ImGui_ImplDX12_InvalidateDeviceObjects();
+
+    // Create the root signature
+    {
+        D3D12_DESCRIPTOR_RANGE descRange = {};
+        descRange.RangeType = D3D12_DESCRIPTOR_RANGE_TYPE_SRV;
+        descRange.NumDescriptors = 1;
+        descRange.BaseShaderRegister = 0;
+        descRange.RegisterSpace = 0;
+        descRange.OffsetInDescriptorsFromTableStart = 0;
+
+        D3D12_ROOT_PARAMETER param[2] = {};
+
+        param[0].ParameterType = D3D12_ROOT_PARAMETER_TYPE_32BIT_CONSTANTS;
+        param[0].Constants.ShaderRegister = 0;
+        param[0].Constants.RegisterSpace = 0;
+        param[0].Constants.Num32BitValues = 16;
+        param[0].ShaderVisibility = D3D12_SHADER_VISIBILITY_VERTEX;
+
+        param[1].ParameterType = D3D12_ROOT_PARAMETER_TYPE_DESCRIPTOR_TABLE;
+        param[1].DescriptorTable.NumDescriptorRanges = 1;
+        param[1].DescriptorTable.pDescriptorRanges = &descRange;
+        param[1].ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;
+
+        // Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling.
+        D3D12_STATIC_SAMPLER_DESC staticSampler = {};
+        staticSampler.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
+        staticSampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
+        staticSampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
+        staticSampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
+        staticSampler.MipLODBias = 0.f;
+        staticSampler.MaxAnisotropy = 0;
+        staticSampler.ComparisonFunc = D3D12_COMPARISON_FUNC_ALWAYS;
+        staticSampler.BorderColor = D3D12_STATIC_BORDER_COLOR_TRANSPARENT_BLACK;
+        staticSampler.MinLOD = 0.f;
+        staticSampler.MaxLOD = 0.f;
+        staticSampler.ShaderRegister = 0;
+        staticSampler.RegisterSpace = 0;
+        staticSampler.ShaderVisibility = D3D12_SHADER_VISIBILITY_PIXEL;
+
+        D3D12_ROOT_SIGNATURE_DESC desc = {};
+        desc.NumParameters = _countof(param);
+        desc.pParameters = param;
+        desc.NumStaticSamplers = 1;
+        desc.pStaticSamplers = &staticSampler;
+        desc.Flags =
+            D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT |
+            D3D12_ROOT_SIGNATURE_FLAG_DENY_HULL_SHADER_ROOT_ACCESS |
+            D3D12_ROOT_SIGNATURE_FLAG_DENY_DOMAIN_SHADER_ROOT_ACCESS |
+            D3D12_ROOT_SIGNATURE_FLAG_DENY_GEOMETRY_SHADER_ROOT_ACCESS;
+
+        // Load d3d12.dll and D3D12SerializeRootSignature() function address dynamically to facilitate using with D3D12On7.
+        // See if any version of d3d12.dll is already loaded in the process. If so, give preference to that.
+        static HINSTANCE d3d12_dll = ::GetModuleHandleA("d3d12.dll");
+        if (d3d12_dll == nullptr)
+        {
+            // Attempt to load d3d12.dll from local directories. This will only succeed if
+            // (1) the current OS is Windows 7, and
+            // (2) there exists a version of d3d12.dll for Windows 7 (D3D12On7) in one of the following directories.
+            // See https://github.com/ocornut/imgui/pull/3696 for details.
+            const char* localD3d12Paths[] = { ".\\d3d12.dll", ".\\d3d12on7\\d3d12.dll", ".\\12on7\\d3d12.dll" }; // A. current directory, B. used by some games, C. used in Microsoft D3D12On7 sample
+            for (int i = 0; i < IM_ARRAYSIZE(localD3d12Paths); i++)
+                if ((d3d12_dll = ::LoadLibraryA(localD3d12Paths[i])) != nullptr)
+                    break;
+
+            // If failed, we are on Windows >= 10.
+            if (d3d12_dll == nullptr)
+                d3d12_dll = ::LoadLibraryA("d3d12.dll");
+
+            if (d3d12_dll == nullptr)
+                return false;
+        }
+
+        PFN_D3D12_SERIALIZE_ROOT_SIGNATURE D3D12SerializeRootSignatureFn = (PFN_D3D12_SERIALIZE_ROOT_SIGNATURE)::GetProcAddress(d3d12_dll, "D3D12SerializeRootSignature");
+        if (D3D12SerializeRootSignatureFn == nullptr)
+            return false;
+
+        ID3DBlob* blob = nullptr;
+        if (D3D12SerializeRootSignatureFn(&desc, D3D_ROOT_SIGNATURE_VERSION_1, &blob, nullptr) != S_OK)
+            return false;
+
+        bd->pd3dDevice->CreateRootSignature(0, blob->GetBufferPointer(), blob->GetBufferSize(), IID_PPV_ARGS(&bd->pRootSignature));
+        blob->Release();
+    }
+
+    // By using D3DCompile() from <d3dcompiler.h> / d3dcompiler.lib, we introduce a dependency to a given version of d3dcompiler_XX.dll (see D3DCOMPILER_DLL_A)
+    // If you would like to use this DX12 sample code but remove this dependency you can:
+    //  1) compile once, save the compiled shader blobs into a file or source code and assign them to psoDesc.VS/PS [preferred solution]
+    //  2) use code to detect any version of the DLL and grab a pointer to D3DCompile from the DLL.
+    // See https://github.com/ocornut/imgui/pull/638 for sources and details.
+
+    D3D12_GRAPHICS_PIPELINE_STATE_DESC psoDesc;
+    memset(&psoDesc, 0, sizeof(D3D12_GRAPHICS_PIPELINE_STATE_DESC));
+    psoDesc.NodeMask = 1;
+    psoDesc.PrimitiveTopologyType = D3D12_PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE;
+    psoDesc.pRootSignature = bd->pRootSignature;
+    psoDesc.SampleMask = UINT_MAX;
+    psoDesc.NumRenderTargets = 1;
+    psoDesc.RTVFormats[0] = bd->RTVFormat;
+    psoDesc.SampleDesc.Count = 1;
+    psoDesc.Flags = D3D12_PIPELINE_STATE_FLAG_NONE;
+
+    ID3DBlob* vertexShaderBlob;
+    ID3DBlob* pixelShaderBlob;
+
+    // Create the vertex shader
+    {
+        static const char* vertexShader =
+            "cbuffer vertexBuffer : register(b0) \
+            {\
+              float4x4 ProjectionMatrix; \
+            };\
+            struct VS_INPUT\
+            {\
+              float2 pos : POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            struct PS_INPUT\
+            {\
+              float4 pos : SV_POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            \
+            PS_INPUT main(VS_INPUT input)\
+            {\
+              PS_INPUT output;\
+              output.pos = mul( ProjectionMatrix, float4(input.pos.xy, 0.f, 1.f));\
+              output.col = input.col;\
+              output.uv  = input.uv;\
+              return output;\
+            }";
+
+        if (FAILED(D3DCompile(vertexShader, strlen(vertexShader), nullptr, nullptr, nullptr, "main", "vs_5_0", 0, 0, &vertexShaderBlob, nullptr)))
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        psoDesc.VS = { vertexShaderBlob->GetBufferPointer(), vertexShaderBlob->GetBufferSize() };
+
+        // Create the input layout
+        static D3D12_INPUT_ELEMENT_DESC local_layout[] =
+        {
+            { "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, pos), D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
+            { "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT,   0, (UINT)IM_OFFSETOF(ImDrawVert, uv),  D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
+            { "COLOR",    0, DXGI_FORMAT_R8G8B8A8_UNORM, 0, (UINT)IM_OFFSETOF(ImDrawVert, col), D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
+        };
+        psoDesc.InputLayout = { local_layout, 3 };
+    }
+
+    // Create the pixel shader
+    {
+        static const char* pixelShader =
+            "struct PS_INPUT\
+            {\
+              float4 pos : SV_POSITION;\
+              float4 col : COLOR0;\
+              float2 uv  : TEXCOORD0;\
+            };\
+            SamplerState sampler0 : register(s0);\
+            Texture2D texture0 : register(t0);\
+            \
+            float4 main(PS_INPUT input) : SV_Target\
+            {\
+              float4 out_col = input.col * texture0.Sample(sampler0, input.uv); \
+              return out_col; \
+            }";
+
+        if (FAILED(D3DCompile(pixelShader, strlen(pixelShader), nullptr, nullptr, nullptr, "main", "ps_5_0", 0, 0, &pixelShaderBlob, nullptr)))
+        {
+            vertexShaderBlob->Release();
+            return false; // NB: Pass ID3DBlob* pErrorBlob to D3DCompile() to get error showing in (const char*)pErrorBlob->GetBufferPointer(). Make sure to Release() the blob!
+        }
+        psoDesc.PS = { pixelShaderBlob->GetBufferPointer(), pixelShaderBlob->GetBufferSize() };
+    }
+
+    // Create the blending setup
+    {
+        D3D12_BLEND_DESC& desc = psoDesc.BlendState;
+        desc.AlphaToCoverageEnable = false;
+        desc.RenderTarget[0].BlendEnable = true;
+        desc.RenderTarget[0].SrcBlend = D3D12_BLEND_SRC_ALPHA;
+        desc.RenderTarget[0].DestBlend = D3D12_BLEND_INV_SRC_ALPHA;
+        desc.RenderTarget[0].BlendOp = D3D12_BLEND_OP_ADD;
+        desc.RenderTarget[0].SrcBlendAlpha = D3D12_BLEND_ONE;
+        desc.RenderTarget[0].DestBlendAlpha = D3D12_BLEND_INV_SRC_ALPHA;
+        desc.RenderTarget[0].BlendOpAlpha = D3D12_BLEND_OP_ADD;
+        desc.RenderTarget[0].RenderTargetWriteMask = D3D12_COLOR_WRITE_ENABLE_ALL;
+    }
+
+    // Create the rasterizer state
+    {
+        D3D12_RASTERIZER_DESC& desc = psoDesc.RasterizerState;
+        desc.FillMode = D3D12_FILL_MODE_SOLID;
+        desc.CullMode = D3D12_CULL_MODE_NONE;
+        desc.FrontCounterClockwise = FALSE;
+        desc.DepthBias = D3D12_DEFAULT_DEPTH_BIAS;
+        desc.DepthBiasClamp = D3D12_DEFAULT_DEPTH_BIAS_CLAMP;
+        desc.SlopeScaledDepthBias = D3D12_DEFAULT_SLOPE_SCALED_DEPTH_BIAS;
+        desc.DepthClipEnable = true;
+        desc.MultisampleEnable = FALSE;
+        desc.AntialiasedLineEnable = FALSE;
+        desc.ForcedSampleCount = 0;
+        desc.ConservativeRaster = D3D12_CONSERVATIVE_RASTERIZATION_MODE_OFF;
+    }
+
+    // Create depth-stencil State
+    {
+        D3D12_DEPTH_STENCIL_DESC& desc = psoDesc.DepthStencilState;
+        desc.DepthEnable = false;
+        desc.DepthWriteMask = D3D12_DEPTH_WRITE_MASK_ALL;
+        desc.DepthFunc = D3D12_COMPARISON_FUNC_ALWAYS;
+        desc.StencilEnable = false;
+        desc.FrontFace.StencilFailOp = desc.FrontFace.StencilDepthFailOp = desc.FrontFace.StencilPassOp = D3D12_STENCIL_OP_KEEP;
+        desc.FrontFace.StencilFunc = D3D12_COMPARISON_FUNC_ALWAYS;
+        desc.BackFace = desc.FrontFace;
+    }
+
+    HRESULT result_pipeline_state = bd->pd3dDevice->CreateGraphicsPipelineState(&psoDesc, IID_PPV_ARGS(&bd->pPipelineState));
+    vertexShaderBlob->Release();
+    pixelShaderBlob->Release();
+    if (result_pipeline_state != S_OK)
+        return false;
+
+    ImGui_ImplDX12_CreateFontsTexture();
+
+    return true;
+}
+
+void    ImGui_ImplDX12_InvalidateDeviceObjects()
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    if (!bd || !bd->pd3dDevice)
+        return;
+
+    ImGuiIO& io = ImGui::GetIO();
+    SafeRelease(bd->pRootSignature);
+    SafeRelease(bd->pPipelineState);
+    SafeRelease(bd->pFontTextureResource);
+    io.Fonts->SetTexID(0); // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+
+    for (UINT i = 0; i < bd->numFramesInFlight; i++)
+    {
+        ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
+        SafeRelease(fr->IndexBuffer);
+        SafeRelease(fr->VertexBuffer);
+    }
+}
+
+bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* cbv_srv_heap,
+                         D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplDX12_Data* bd = IM_NEW(ImGui_ImplDX12_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_dx12";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->pd3dDevice = device;
+    bd->RTVFormat = rtv_format;
+    bd->hFontSrvCpuDescHandle = font_srv_cpu_desc_handle;
+    bd->hFontSrvGpuDescHandle = font_srv_gpu_desc_handle;
+    bd->pFrameResources = new ImGui_ImplDX12_RenderBuffers[num_frames_in_flight];
+    bd->numFramesInFlight = num_frames_in_flight;
+    bd->pd3dSrvDescHeap = cbv_srv_heap;
+    bd->frameIndex = UINT_MAX;
+
+    // Create buffers with a default size (they will later be grown as needed)
+    for (int i = 0; i < num_frames_in_flight; i++)
+    {
+        ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
+        fr->IndexBuffer = nullptr;
+        fr->VertexBuffer = nullptr;
+        fr->IndexBufferSize = 10000;
+        fr->VertexBufferSize = 5000;
+    }
+
+    return true;
+}
+
+void ImGui_ImplDX12_Shutdown()
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Clean up windows and device objects
+    ImGui_ImplDX12_InvalidateDeviceObjects();
+    delete[] bd->pFrameResources;
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+void ImGui_ImplDX12_NewFrame()
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX12_Init()?");
+
+    if (!bd->pPipelineState)
+        ImGui_ImplDX12_CreateDeviceObjects();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx12.h

@@ -0,0 +1,44 @@
+// dear imgui: Renderer Backend for DirectX12
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
+// See imgui_impl_dx12.cpp file for details.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+#include <dxgiformat.h> // DXGI_FORMAT
+
+struct ID3D12Device;
+struct ID3D12DescriptorHeap;
+struct ID3D12GraphicsCommandList;
+struct D3D12_CPU_DESCRIPTOR_HANDLE;
+struct D3D12_GPU_DESCRIPTOR_HANDLE;
+
+// cmd_list is the command list that the implementation will use to render imgui draw lists.
+// Before calling the render function, caller must prepare cmd_list by resetting it and setting the appropriate
+// render target and descriptor heap that contains font_srv_cpu_desc_handle/font_srv_gpu_desc_handle.
+// font_srv_cpu_desc_handle and font_srv_gpu_desc_handle are handles to a single SRV descriptor to use for the internal font texture.
+IMGUI_IMPL_API bool     ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* cbv_srv_heap,
+                                            D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle);
+IMGUI_IMPL_API void     ImGui_ImplDX12_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplDX12_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* graphics_command_list);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API void     ImGui_ImplDX12_InvalidateDeviceObjects();
+IMGUI_IMPL_API bool     ImGui_ImplDX12_CreateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx9.cpp

@@ -0,0 +1,388 @@
+// dear imgui: Renderer Backend for DirectX9
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-06-25: DirectX9: Explicitly disable texture state stages after >= 1.
+//  2021-05-19: DirectX9: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-04-23: DirectX9: Explicitly setting up more graphics states to increase compatibility with unusual non-default states.
+//  2021-03-18: DirectX9: Calling IDirect3DStateBlock9::Capture() after CreateStateBlock() as a workaround for state restoring issues (see #3857).
+//  2021-03-03: DirectX9: Added support for IMGUI_USE_BGRA_PACKED_COLOR in user's imconfig file.
+//  2021-02-18: DirectX9: Change blending equation to preserve alpha in output buffer.
+//  2019-05-29: DirectX9: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: DirectX9: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2019-03-29: Misc: Fixed erroneous assert in ImGui_ImplDX9_InvalidateDeviceObjects().
+//  2019-01-16: Misc: Disabled fog before drawing UI's. Fixes issue #2288.
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-06-08: Misc: Extracted imgui_impl_dx9.cpp/.h away from the old combined DX9+Win32 example.
+//  2018-06-08: DirectX9: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-05-07: Render: Saving/restoring Transform because they don't seem to be included in the StateBlock. Setting shading mode to Gouraud.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX9_RenderDrawData() in the .h file so you can call it yourself.
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_dx9.h"
+
+// DirectX
+#include <d3d9.h>
+
+// DirectX data
+struct ImGui_ImplDX9_Data
+{
+    LPDIRECT3DDEVICE9           pd3dDevice;
+    LPDIRECT3DVERTEXBUFFER9     pVB;
+    LPDIRECT3DINDEXBUFFER9      pIB;
+    LPDIRECT3DTEXTURE9          FontTexture;
+    int                         VertexBufferSize;
+    int                         IndexBufferSize;
+
+    ImGui_ImplDX9_Data()        { memset((void*)this, 0, sizeof(*this)); VertexBufferSize = 5000; IndexBufferSize = 10000; }
+};
+
+struct CUSTOMVERTEX
+{
+    float    pos[3];
+    D3DCOLOR col;
+    float    uv[2];
+};
+#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE|D3DFVF_TEX1)
+
+#ifdef IMGUI_USE_BGRA_PACKED_COLOR
+#define IMGUI_COL_TO_DX9_ARGB(_COL)     (_COL)
+#else
+#define IMGUI_COL_TO_DX9_ARGB(_COL)     (((_COL) & 0xFF00FF00) | (((_COL) & 0xFF0000) >> 16) | (((_COL) & 0xFF) << 16))
+#endif
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplDX9_Data* ImGui_ImplDX9_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplDX9_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+static void ImGui_ImplDX9_SetupRenderState(ImDrawData* draw_data)
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+
+    // Setup viewport
+    D3DVIEWPORT9 vp;
+    vp.X = vp.Y = 0;
+    vp.Width = (DWORD)draw_data->DisplaySize.x;
+    vp.Height = (DWORD)draw_data->DisplaySize.y;
+    vp.MinZ = 0.0f;
+    vp.MaxZ = 1.0f;
+    bd->pd3dDevice->SetViewport(&vp);
+
+    // Setup render state: fixed-pipeline, alpha-blending, no face culling, no depth testing, shade mode (for gradient), bilinear sampling.
+    bd->pd3dDevice->SetPixelShader(nullptr);
+    bd->pd3dDevice->SetVertexShader(nullptr);
+    bd->pd3dDevice->SetRenderState(D3DRS_FILLMODE, D3DFILL_SOLID);
+    bd->pd3dDevice->SetRenderState(D3DRS_SHADEMODE, D3DSHADE_GOURAUD);
+    bd->pd3dDevice->SetRenderState(D3DRS_ZWRITEENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_ALPHATESTENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
+    bd->pd3dDevice->SetRenderState(D3DRS_ZENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);
+    bd->pd3dDevice->SetRenderState(D3DRS_BLENDOP, D3DBLENDOP_ADD);
+    bd->pd3dDevice->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
+    bd->pd3dDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
+    bd->pd3dDevice->SetRenderState(D3DRS_SEPARATEALPHABLENDENABLE, TRUE);
+    bd->pd3dDevice->SetRenderState(D3DRS_SRCBLENDALPHA, D3DBLEND_ONE);
+    bd->pd3dDevice->SetRenderState(D3DRS_DESTBLENDALPHA, D3DBLEND_INVSRCALPHA);
+    bd->pd3dDevice->SetRenderState(D3DRS_SCISSORTESTENABLE, TRUE);
+    bd->pd3dDevice->SetRenderState(D3DRS_FOGENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_RANGEFOGENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_SPECULARENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_STENCILENABLE, FALSE);
+    bd->pd3dDevice->SetRenderState(D3DRS_CLIPPING, TRUE);
+    bd->pd3dDevice->SetRenderState(D3DRS_LIGHTING, FALSE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLOROP, D3DTOP_MODULATE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_TEXTURE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG2, D3DTA_DIFFUSE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_MODULATE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
+    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE);
+    bd->pd3dDevice->SetTextureStageState(1, D3DTSS_COLOROP, D3DTOP_DISABLE);
+    bd->pd3dDevice->SetTextureStageState(1, D3DTSS_ALPHAOP, D3DTOP_DISABLE);
+    bd->pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
+    bd->pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);
+
+    // Setup orthographic projection matrix
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
+    // Being agnostic of whether <d3dx9.h> or <DirectXMath.h> can be used, we aren't relying on D3DXMatrixIdentity()/D3DXMatrixOrthoOffCenterLH() or DirectX::XMMatrixIdentity()/DirectX::XMMatrixOrthographicOffCenterLH()
+    {
+        float L = draw_data->DisplayPos.x + 0.5f;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x + 0.5f;
+        float T = draw_data->DisplayPos.y + 0.5f;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y + 0.5f;
+        D3DMATRIX mat_identity = { { { 1.0f, 0.0f, 0.0f, 0.0f,  0.0f, 1.0f, 0.0f, 0.0f,  0.0f, 0.0f, 1.0f, 0.0f,  0.0f, 0.0f, 0.0f, 1.0f } } };
+        D3DMATRIX mat_projection =
+        { { {
+            2.0f/(R-L),   0.0f,         0.0f,  0.0f,
+            0.0f,         2.0f/(T-B),   0.0f,  0.0f,
+            0.0f,         0.0f,         0.5f,  0.0f,
+            (L+R)/(L-R),  (T+B)/(B-T),  0.5f,  1.0f
+        } } };
+        bd->pd3dDevice->SetTransform(D3DTS_WORLD, &mat_identity);
+        bd->pd3dDevice->SetTransform(D3DTS_VIEW, &mat_identity);
+        bd->pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat_projection);
+    }
+}
+
+// Render function.
+void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    // Create and grow buffers if needed
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
+    {
+        if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
+        bd->VertexBufferSize = draw_data->TotalVtxCount + 5000;
+        if (bd->pd3dDevice->CreateVertexBuffer(bd->VertexBufferSize * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &bd->pVB, nullptr) < 0)
+            return;
+    }
+    if (!bd->pIB || bd->IndexBufferSize < draw_data->TotalIdxCount)
+    {
+        if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
+        bd->IndexBufferSize = draw_data->TotalIdxCount + 10000;
+        if (bd->pd3dDevice->CreateIndexBuffer(bd->IndexBufferSize * sizeof(ImDrawIdx), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, sizeof(ImDrawIdx) == 2 ? D3DFMT_INDEX16 : D3DFMT_INDEX32, D3DPOOL_DEFAULT, &bd->pIB, nullptr) < 0)
+            return;
+    }
+
+    // Backup the DX9 state
+    IDirect3DStateBlock9* d3d9_state_block = nullptr;
+    if (bd->pd3dDevice->CreateStateBlock(D3DSBT_ALL, &d3d9_state_block) < 0)
+        return;
+    if (d3d9_state_block->Capture() < 0)
+    {
+        d3d9_state_block->Release();
+        return;
+    }
+
+    // Backup the DX9 transform (DX9 documentation suggests that it is included in the StateBlock but it doesn't appear to)
+    D3DMATRIX last_world, last_view, last_projection;
+    bd->pd3dDevice->GetTransform(D3DTS_WORLD, &last_world);
+    bd->pd3dDevice->GetTransform(D3DTS_VIEW, &last_view);
+    bd->pd3dDevice->GetTransform(D3DTS_PROJECTION, &last_projection);
+
+    // Allocate buffers
+    CUSTOMVERTEX* vtx_dst;
+    ImDrawIdx* idx_dst;
+    if (bd->pVB->Lock(0, (UINT)(draw_data->TotalVtxCount * sizeof(CUSTOMVERTEX)), (void**)&vtx_dst, D3DLOCK_DISCARD) < 0)
+    {
+        d3d9_state_block->Release();
+        return;
+    }
+    if (bd->pIB->Lock(0, (UINT)(draw_data->TotalIdxCount * sizeof(ImDrawIdx)), (void**)&idx_dst, D3DLOCK_DISCARD) < 0)
+    {
+        bd->pVB->Unlock();
+        d3d9_state_block->Release();
+        return;
+    }
+
+    // Copy and convert all vertices into a single contiguous buffer, convert colors to DX9 default format.
+    // FIXME-OPT: This is a minor waste of resource, the ideal is to use imconfig.h and
+    //  1) to avoid repacking colors:   #define IMGUI_USE_BGRA_PACKED_COLOR
+    //  2) to avoid repacking vertices: #define IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT struct ImDrawVert { ImVec2 pos; float z; ImU32 col; ImVec2 uv; }
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_src = cmd_list->VtxBuffer.Data;
+        for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
+        {
+            vtx_dst->pos[0] = vtx_src->pos.x;
+            vtx_dst->pos[1] = vtx_src->pos.y;
+            vtx_dst->pos[2] = 0.0f;
+            vtx_dst->col = IMGUI_COL_TO_DX9_ARGB(vtx_src->col);
+            vtx_dst->uv[0] = vtx_src->uv.x;
+            vtx_dst->uv[1] = vtx_src->uv.y;
+            vtx_dst++;
+            vtx_src++;
+        }
+        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        idx_dst += cmd_list->IdxBuffer.Size;
+    }
+    bd->pVB->Unlock();
+    bd->pIB->Unlock();
+    bd->pd3dDevice->SetStreamSource(0, bd->pVB, 0, sizeof(CUSTOMVERTEX));
+    bd->pd3dDevice->SetIndices(bd->pIB);
+    bd->pd3dDevice->SetFVF(D3DFVF_CUSTOMVERTEX);
+
+    // Setup desired DX state
+    ImGui_ImplDX9_SetupRenderState(draw_data);
+
+    // Render command lists
+    // (Because we merged all buffers into a single one, we maintain our own offset into them)
+    int global_vtx_offset = 0;
+    int global_idx_offset = 0;
+    ImVec2 clip_off = draw_data->DisplayPos;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback != nullptr)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplDX9_SetupRenderState(draw_data);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+                ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply Scissor/clipping rectangle, Bind texture, Draw
+                const RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                const LPDIRECT3DTEXTURE9 texture = (LPDIRECT3DTEXTURE9)pcmd->GetTexID();
+                bd->pd3dDevice->SetTexture(0, texture);
+                bd->pd3dDevice->SetScissorRect(&r);
+                bd->pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, pcmd->VtxOffset + global_vtx_offset, 0, (UINT)cmd_list->VtxBuffer.Size, pcmd->IdxOffset + global_idx_offset, pcmd->ElemCount / 3);
+            }
+        }
+        global_idx_offset += cmd_list->IdxBuffer.Size;
+        global_vtx_offset += cmd_list->VtxBuffer.Size;
+    }
+
+    // Restore the DX9 transform
+    bd->pd3dDevice->SetTransform(D3DTS_WORLD, &last_world);
+    bd->pd3dDevice->SetTransform(D3DTS_VIEW, &last_view);
+    bd->pd3dDevice->SetTransform(D3DTS_PROJECTION, &last_projection);
+
+    // Restore the DX9 state
+    d3d9_state_block->Apply();
+    d3d9_state_block->Release();
+}
+
+bool ImGui_ImplDX9_Init(IDirect3DDevice9* device)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplDX9_Data* bd = IM_NEW(ImGui_ImplDX9_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_dx9";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->pd3dDevice = device;
+    bd->pd3dDevice->AddRef();
+
+    return true;
+}
+
+void ImGui_ImplDX9_Shutdown()
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplDX9_InvalidateDeviceObjects();
+    if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+static bool ImGui_ImplDX9_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    unsigned char* pixels;
+    int width, height, bytes_per_pixel;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &bytes_per_pixel);
+
+    // Convert RGBA32 to BGRA32 (because RGBA32 is not well supported by DX9 devices)
+#ifndef IMGUI_USE_BGRA_PACKED_COLOR
+    if (io.Fonts->TexPixelsUseColors)
+    {
+        ImU32* dst_start = (ImU32*)ImGui::MemAlloc((size_t)width * height * bytes_per_pixel);
+        for (ImU32* src = (ImU32*)pixels, *dst = dst_start, *dst_end = dst_start + (size_t)width * height; dst < dst_end; src++, dst++)
+            *dst = IMGUI_COL_TO_DX9_ARGB(*src);
+        pixels = (unsigned char*)dst_start;
+    }
+#endif
+
+    // Upload texture to graphics system
+    bd->FontTexture = nullptr;
+    if (bd->pd3dDevice->CreateTexture(width, height, 1, D3DUSAGE_DYNAMIC, D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &bd->FontTexture, nullptr) < 0)
+        return false;
+    D3DLOCKED_RECT tex_locked_rect;
+    if (bd->FontTexture->LockRect(0, &tex_locked_rect, nullptr, 0) != D3D_OK)
+        return false;
+    for (int y = 0; y < height; y++)
+        memcpy((unsigned char*)tex_locked_rect.pBits + (size_t)tex_locked_rect.Pitch * y, pixels + (size_t)width * bytes_per_pixel * y, (size_t)width * bytes_per_pixel);
+    bd->FontTexture->UnlockRect(0);
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)bd->FontTexture);
+
+#ifndef IMGUI_USE_BGRA_PACKED_COLOR
+    if (io.Fonts->TexPixelsUseColors)
+        ImGui::MemFree(pixels);
+#endif
+
+    return true;
+}
+
+bool ImGui_ImplDX9_CreateDeviceObjects()
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    if (!bd || !bd->pd3dDevice)
+        return false;
+    if (!ImGui_ImplDX9_CreateFontsTexture())
+        return false;
+    return true;
+}
+
+void ImGui_ImplDX9_InvalidateDeviceObjects()
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    if (!bd || !bd->pd3dDevice)
+        return;
+    if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
+    if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
+    if (bd->FontTexture) { bd->FontTexture->Release(); bd->FontTexture = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+}
+
+void ImGui_ImplDX9_NewFrame()
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX9_Init()?");
+
+    if (!bd->FontTexture)
+        ImGui_ImplDX9_CreateDeviceObjects();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_dx9.h

@@ -0,0 +1,31 @@
+// dear imgui: Renderer Backend for DirectX9
+// This needs to be used along with a Platform Backend (e.g. Win32)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct IDirect3DDevice9;
+
+IMGUI_IMPL_API bool     ImGui_ImplDX9_Init(IDirect3DDevice9* device);
+IMGUI_IMPL_API void     ImGui_ImplDX9_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplDX9_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API bool     ImGui_ImplDX9_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplDX9_InvalidateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_glfw.cpp

@@ -0,0 +1,803 @@
+// dear imgui: Platform Backend for GLFW
+// This needs to be used along with a Renderer (e.g. OpenGL3, Vulkan, WebGPU..)
+// (Info: GLFW is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
+// (Requires: GLFW 3.1+. Prefer GLFW 3.3+ or GLFW 3.4+ for full feature support.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen (Windows only).
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLFW_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange' (note: the resizing cursors requires GLFW 3.4+).
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-07-18: Inputs: Revert ignoring mouse data on GLFW_CURSOR_DISABLED as it can be used differently. User may set ImGuiConfigFLags_NoMouse if desired. (#5625, #6609)
+//  2023-06-12: Accept glfwGetTime() not returning a monotonically increasing value. This seems to happens on some Windows setup when peripherals disconnect, and is likely to also happen on browser + Emscripten. (#6491)
+//  2023-04-04: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_TouchScreen/ImGuiMouseSource_Pen on Windows ONLY, using a custom WndProc hook. (#2702)
+//  2023-03-16: Inputs: Fixed key modifiers handling on secondary viewports (docking branch). Broken on 2023/01/04. (#6248, #6034)
+//  2023-03-14: Emscripten: Avoid using glfwGetError() and glfwGetGamepadState() which are not correctly implemented in Emscripten emulation. (#6240)
+//  2023-02-03: Emscripten: Registering custom low-level mouse wheel handler to get more accurate scrolling impulses on Emscripten. (#4019, #6096)
+//  2023-01-04: Inputs: Fixed mods state on Linux when using Alt-GR text input (e.g. German keyboard layout), could lead to broken text input. Revert a 2022/01/17 change were we resumed using mods provided by GLFW, turns out they were faulty.
+//  2022-11-22: Perform a dummy glfwGetError() read to cancel missing names with glfwGetKeyName(). (#5908)
+//  2022-10-18: Perform a dummy glfwGetError() read to cancel missing mouse cursors errors. Using GLFW_VERSION_COMBINED directly. (#5785)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-09-01: Inputs: Honor GLFW_CURSOR_DISABLED by not setting mouse position *EDIT* Reverted 2023-07-18.
+//  2022-04-30: Inputs: Fixed ImGui_ImplGlfw_TranslateUntranslatedKey() for lower case letters on OSX.
+//  2022-03-23: Inputs: Fixed a regression in 1.87 which resulted in keyboard modifiers events being reported incorrectly on Linux/X11.
+//  2022-02-07: Added ImGui_ImplGlfw_InstallCallbacks()/ImGui_ImplGlfw_RestoreCallbacks() helpers to facilitate user installing callbacks after initializing backend.
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2021-01-20: Inputs: calling new io.AddKeyAnalogEvent() for gamepad support, instead of writing directly to io.NavInputs[].
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-17: Inputs: always update key mods next and before key event (not in NewFrame) to fix input queue with very low framerates.
+//  2022-01-12: *BREAKING CHANGE*: Now using glfwSetCursorPosCallback(). If you called ImGui_ImplGlfw_InitXXX() with install_callbacks = false, you MUST install glfwSetCursorPosCallback() and forward it to the backend via ImGui_ImplGlfw_CursorPosCallback().
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2022-01-05: Inputs: Converting GLFW untranslated keycodes back to translated keycodes (in the ImGui_ImplGlfw_KeyCallback() function) in order to match the behavior of every other backend, and facilitate the use of GLFW with lettered-shortcuts API.
+//  2021-08-17: *BREAKING CHANGE*: Now using glfwSetWindowFocusCallback() to calling io.AddFocusEvent(). If you called ImGui_ImplGlfw_InitXXX() with install_callbacks = false, you MUST install glfwSetWindowFocusCallback() and forward it to the backend via ImGui_ImplGlfw_WindowFocusCallback().
+//  2021-07-29: *BREAKING CHANGE*: Now using glfwSetCursorEnterCallback(). MousePos is correctly reported when the host platform window is hovered but not focused. If you called ImGui_ImplGlfw_InitXXX() with install_callbacks = false, you MUST install glfwSetWindowFocusCallback() callback and forward it to the backend via ImGui_ImplGlfw_CursorEnterCallback().
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2020-01-17: Inputs: Disable error callback while assigning mouse cursors because some X11 setup don't have them and it generates errors.
+//  2019-12-05: Inputs: Added support for new mouse cursors added in GLFW 3.4+ (resizing cursors, not allowed cursor).
+//  2019-10-18: Misc: Previously installed user callbacks are now restored on shutdown.
+//  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
+//  2019-05-11: Inputs: Don't filter value from character callback before calling AddInputCharacter().
+//  2019-03-12: Misc: Preserve DisplayFramebufferScale when main window is minimized.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-11-07: Inputs: When installing our GLFW callbacks, we save user's previously installed ones - if any - and chain call them.
+//  2018-08-01: Inputs: Workaround for Emscripten which doesn't seem to handle focus related calls.
+//  2018-06-29: Inputs: Added support for the ImGuiMouseCursor_Hand cursor.
+//  2018-06-08: Misc: Extracted imgui_impl_glfw.cpp/.h away from the old combined GLFW+OpenGL/Vulkan examples.
+//  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-02-20: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value, passed to glfwSetCursor()).
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
+//  2018-01-25: Inputs: Added gamepad support if ImGuiConfigFlags_NavEnableGamepad is set.
+//  2018-01-25: Inputs: Honoring the io.WantSetMousePos by repositioning the mouse (when using navigation and ImGuiConfigFlags_NavMoveMouse is set).
+//  2018-01-20: Inputs: Added Horizontal Mouse Wheel support.
+//  2018-01-18: Inputs: Added mapping for ImGuiKey_Insert.
+//  2017-08-25: Inputs: MousePos set to -FLT_MAX,-FLT_MAX when mouse is unavailable/missing (instead of -1,-1).
+//  2016-10-15: Misc: Added a void* user_data parameter to Clipboard function handlers.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_glfw.h"
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wold-style-cast"     // warning: use of old-style cast
+#pragma clang diagnostic ignored "-Wsign-conversion"    // warning: implicit conversion changes signedness
+#endif
+
+// GLFW
+#include <GLFW/glfw3.h>
+
+#ifdef _WIN32
+#undef APIENTRY
+#define GLFW_EXPOSE_NATIVE_WIN32
+#include <GLFW/glfw3native.h>   // for glfwGetWin32Window()
+#endif
+#ifdef __APPLE__
+#define GLFW_EXPOSE_NATIVE_COCOA
+#include <GLFW/glfw3native.h>   // for glfwGetCocoaWindow()
+#endif
+
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#include <emscripten/html5.h>
+#endif
+
+// We gather version tests as define in order to easily see which features are version-dependent.
+#define GLFW_VERSION_COMBINED           (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 + GLFW_VERSION_REVISION)
+#ifdef GLFW_RESIZE_NESW_CURSOR          // Let's be nice to people who pulled GLFW between 2019-04-16 (3.4 define) and 2019-11-29 (cursors defines) // FIXME: Remove when GLFW 3.4 is released?
+#define GLFW_HAS_NEW_CURSORS            (GLFW_VERSION_COMBINED >= 3400) // 3.4+ GLFW_RESIZE_ALL_CURSOR, GLFW_RESIZE_NESW_CURSOR, GLFW_RESIZE_NWSE_CURSOR, GLFW_NOT_ALLOWED_CURSOR
+#else
+#define GLFW_HAS_NEW_CURSORS            (0)
+#endif
+#define GLFW_HAS_GAMEPAD_API            (GLFW_VERSION_COMBINED >= 3300) // 3.3+ glfwGetGamepadState() new api
+#define GLFW_HAS_GETKEYNAME             (GLFW_VERSION_COMBINED >= 3200) // 3.2+ glfwGetKeyName()
+#define GLFW_HAS_GETERROR               (GLFW_VERSION_COMBINED >= 3300) // 3.3+ glfwGetError()
+
+// GLFW data
+enum GlfwClientApi
+{
+    GlfwClientApi_Unknown,
+    GlfwClientApi_OpenGL,
+    GlfwClientApi_Vulkan
+};
+
+struct ImGui_ImplGlfw_Data
+{
+    GLFWwindow*             Window;
+    GlfwClientApi           ClientApi;
+    double                  Time;
+    GLFWwindow*             MouseWindow;
+    GLFWcursor*             MouseCursors[ImGuiMouseCursor_COUNT];
+    ImVec2                  LastValidMousePos;
+    bool                    InstalledCallbacks;
+    bool                    CallbacksChainForAllWindows;
+
+    // Chain GLFW callbacks: our callbacks will call the user's previously installed callbacks, if any.
+    GLFWwindowfocusfun      PrevUserCallbackWindowFocus;
+    GLFWcursorposfun        PrevUserCallbackCursorPos;
+    GLFWcursorenterfun      PrevUserCallbackCursorEnter;
+    GLFWmousebuttonfun      PrevUserCallbackMousebutton;
+    GLFWscrollfun           PrevUserCallbackScroll;
+    GLFWkeyfun              PrevUserCallbackKey;
+    GLFWcharfun             PrevUserCallbackChar;
+    GLFWmonitorfun          PrevUserCallbackMonitor;
+#ifdef _WIN32
+    WNDPROC                 GlfwWndProc;
+#endif
+
+    ImGui_ImplGlfw_Data()   { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+// - Because glfwPollEvents() process all windows and some events may be called outside of it, you will need to register your own callbacks
+//   (passing install_callbacks=false in ImGui_ImplGlfw_InitXXX functions), set the current dear imgui context and then call our callbacks.
+// - Otherwise we may need to store a GLFWWindow* -> ImGuiContext* map and handle this in the backend, adding a little bit of extra complexity to it.
+// FIXME: some shared resources (mouse cursor shape, gamepad) are mishandled when using multi-context.
+static ImGui_ImplGlfw_Data* ImGui_ImplGlfw_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplGlfw_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
+}
+
+// Functions
+static const char* ImGui_ImplGlfw_GetClipboardText(void* user_data)
+{
+    return glfwGetClipboardString((GLFWwindow*)user_data);
+}
+
+static void ImGui_ImplGlfw_SetClipboardText(void* user_data, const char* text)
+{
+    glfwSetClipboardString((GLFWwindow*)user_data, text);
+}
+
+static ImGuiKey ImGui_ImplGlfw_KeyToImGuiKey(int key)
+{
+    switch (key)
+    {
+        case GLFW_KEY_TAB: return ImGuiKey_Tab;
+        case GLFW_KEY_LEFT: return ImGuiKey_LeftArrow;
+        case GLFW_KEY_RIGHT: return ImGuiKey_RightArrow;
+        case GLFW_KEY_UP: return ImGuiKey_UpArrow;
+        case GLFW_KEY_DOWN: return ImGuiKey_DownArrow;
+        case GLFW_KEY_PAGE_UP: return ImGuiKey_PageUp;
+        case GLFW_KEY_PAGE_DOWN: return ImGuiKey_PageDown;
+        case GLFW_KEY_HOME: return ImGuiKey_Home;
+        case GLFW_KEY_END: return ImGuiKey_End;
+        case GLFW_KEY_INSERT: return ImGuiKey_Insert;
+        case GLFW_KEY_DELETE: return ImGuiKey_Delete;
+        case GLFW_KEY_BACKSPACE: return ImGuiKey_Backspace;
+        case GLFW_KEY_SPACE: return ImGuiKey_Space;
+        case GLFW_KEY_ENTER: return ImGuiKey_Enter;
+        case GLFW_KEY_ESCAPE: return ImGuiKey_Escape;
+        case GLFW_KEY_APOSTROPHE: return ImGuiKey_Apostrophe;
+        case GLFW_KEY_COMMA: return ImGuiKey_Comma;
+        case GLFW_KEY_MINUS: return ImGuiKey_Minus;
+        case GLFW_KEY_PERIOD: return ImGuiKey_Period;
+        case GLFW_KEY_SLASH: return ImGuiKey_Slash;
+        case GLFW_KEY_SEMICOLON: return ImGuiKey_Semicolon;
+        case GLFW_KEY_EQUAL: return ImGuiKey_Equal;
+        case GLFW_KEY_LEFT_BRACKET: return ImGuiKey_LeftBracket;
+        case GLFW_KEY_BACKSLASH: return ImGuiKey_Backslash;
+        case GLFW_KEY_RIGHT_BRACKET: return ImGuiKey_RightBracket;
+        case GLFW_KEY_GRAVE_ACCENT: return ImGuiKey_GraveAccent;
+        case GLFW_KEY_CAPS_LOCK: return ImGuiKey_CapsLock;
+        case GLFW_KEY_SCROLL_LOCK: return ImGuiKey_ScrollLock;
+        case GLFW_KEY_NUM_LOCK: return ImGuiKey_NumLock;
+        case GLFW_KEY_PRINT_SCREEN: return ImGuiKey_PrintScreen;
+        case GLFW_KEY_PAUSE: return ImGuiKey_Pause;
+        case GLFW_KEY_KP_0: return ImGuiKey_Keypad0;
+        case GLFW_KEY_KP_1: return ImGuiKey_Keypad1;
+        case GLFW_KEY_KP_2: return ImGuiKey_Keypad2;
+        case GLFW_KEY_KP_3: return ImGuiKey_Keypad3;
+        case GLFW_KEY_KP_4: return ImGuiKey_Keypad4;
+        case GLFW_KEY_KP_5: return ImGuiKey_Keypad5;
+        case GLFW_KEY_KP_6: return ImGuiKey_Keypad6;
+        case GLFW_KEY_KP_7: return ImGuiKey_Keypad7;
+        case GLFW_KEY_KP_8: return ImGuiKey_Keypad8;
+        case GLFW_KEY_KP_9: return ImGuiKey_Keypad9;
+        case GLFW_KEY_KP_DECIMAL: return ImGuiKey_KeypadDecimal;
+        case GLFW_KEY_KP_DIVIDE: return ImGuiKey_KeypadDivide;
+        case GLFW_KEY_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case GLFW_KEY_KP_SUBTRACT: return ImGuiKey_KeypadSubtract;
+        case GLFW_KEY_KP_ADD: return ImGuiKey_KeypadAdd;
+        case GLFW_KEY_KP_ENTER: return ImGuiKey_KeypadEnter;
+        case GLFW_KEY_KP_EQUAL: return ImGuiKey_KeypadEqual;
+        case GLFW_KEY_LEFT_SHIFT: return ImGuiKey_LeftShift;
+        case GLFW_KEY_LEFT_CONTROL: return ImGuiKey_LeftCtrl;
+        case GLFW_KEY_LEFT_ALT: return ImGuiKey_LeftAlt;
+        case GLFW_KEY_LEFT_SUPER: return ImGuiKey_LeftSuper;
+        case GLFW_KEY_RIGHT_SHIFT: return ImGuiKey_RightShift;
+        case GLFW_KEY_RIGHT_CONTROL: return ImGuiKey_RightCtrl;
+        case GLFW_KEY_RIGHT_ALT: return ImGuiKey_RightAlt;
+        case GLFW_KEY_RIGHT_SUPER: return ImGuiKey_RightSuper;
+        case GLFW_KEY_MENU: return ImGuiKey_Menu;
+        case GLFW_KEY_0: return ImGuiKey_0;
+        case GLFW_KEY_1: return ImGuiKey_1;
+        case GLFW_KEY_2: return ImGuiKey_2;
+        case GLFW_KEY_3: return ImGuiKey_3;
+        case GLFW_KEY_4: return ImGuiKey_4;
+        case GLFW_KEY_5: return ImGuiKey_5;
+        case GLFW_KEY_6: return ImGuiKey_6;
+        case GLFW_KEY_7: return ImGuiKey_7;
+        case GLFW_KEY_8: return ImGuiKey_8;
+        case GLFW_KEY_9: return ImGuiKey_9;
+        case GLFW_KEY_A: return ImGuiKey_A;
+        case GLFW_KEY_B: return ImGuiKey_B;
+        case GLFW_KEY_C: return ImGuiKey_C;
+        case GLFW_KEY_D: return ImGuiKey_D;
+        case GLFW_KEY_E: return ImGuiKey_E;
+        case GLFW_KEY_F: return ImGuiKey_F;
+        case GLFW_KEY_G: return ImGuiKey_G;
+        case GLFW_KEY_H: return ImGuiKey_H;
+        case GLFW_KEY_I: return ImGuiKey_I;
+        case GLFW_KEY_J: return ImGuiKey_J;
+        case GLFW_KEY_K: return ImGuiKey_K;
+        case GLFW_KEY_L: return ImGuiKey_L;
+        case GLFW_KEY_M: return ImGuiKey_M;
+        case GLFW_KEY_N: return ImGuiKey_N;
+        case GLFW_KEY_O: return ImGuiKey_O;
+        case GLFW_KEY_P: return ImGuiKey_P;
+        case GLFW_KEY_Q: return ImGuiKey_Q;
+        case GLFW_KEY_R: return ImGuiKey_R;
+        case GLFW_KEY_S: return ImGuiKey_S;
+        case GLFW_KEY_T: return ImGuiKey_T;
+        case GLFW_KEY_U: return ImGuiKey_U;
+        case GLFW_KEY_V: return ImGuiKey_V;
+        case GLFW_KEY_W: return ImGuiKey_W;
+        case GLFW_KEY_X: return ImGuiKey_X;
+        case GLFW_KEY_Y: return ImGuiKey_Y;
+        case GLFW_KEY_Z: return ImGuiKey_Z;
+        case GLFW_KEY_F1: return ImGuiKey_F1;
+        case GLFW_KEY_F2: return ImGuiKey_F2;
+        case GLFW_KEY_F3: return ImGuiKey_F3;
+        case GLFW_KEY_F4: return ImGuiKey_F4;
+        case GLFW_KEY_F5: return ImGuiKey_F5;
+        case GLFW_KEY_F6: return ImGuiKey_F6;
+        case GLFW_KEY_F7: return ImGuiKey_F7;
+        case GLFW_KEY_F8: return ImGuiKey_F8;
+        case GLFW_KEY_F9: return ImGuiKey_F9;
+        case GLFW_KEY_F10: return ImGuiKey_F10;
+        case GLFW_KEY_F11: return ImGuiKey_F11;
+        case GLFW_KEY_F12: return ImGuiKey_F12;
+        default: return ImGuiKey_None;
+    }
+}
+
+// X11 does not include current pressed/released modifier key in 'mods' flags submitted by GLFW
+// See https://github.com/ocornut/imgui/issues/6034 and https://github.com/glfw/glfw/issues/1630
+static void ImGui_ImplGlfw_UpdateKeyModifiers(GLFWwindow* window)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(ImGuiMod_Ctrl,  (glfwGetKey(window, GLFW_KEY_LEFT_CONTROL) == GLFW_PRESS) || (glfwGetKey(window, GLFW_KEY_RIGHT_CONTROL) == GLFW_PRESS));
+    io.AddKeyEvent(ImGuiMod_Shift, (glfwGetKey(window, GLFW_KEY_LEFT_SHIFT)   == GLFW_PRESS) || (glfwGetKey(window, GLFW_KEY_RIGHT_SHIFT)   == GLFW_PRESS));
+    io.AddKeyEvent(ImGuiMod_Alt,   (glfwGetKey(window, GLFW_KEY_LEFT_ALT)     == GLFW_PRESS) || (glfwGetKey(window, GLFW_KEY_RIGHT_ALT)     == GLFW_PRESS));
+    io.AddKeyEvent(ImGuiMod_Super, (glfwGetKey(window, GLFW_KEY_LEFT_SUPER)   == GLFW_PRESS) || (glfwGetKey(window, GLFW_KEY_RIGHT_SUPER)   == GLFW_PRESS));
+}
+
+static bool ImGui_ImplGlfw_ShouldChainCallback(GLFWwindow* window)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    return bd->CallbacksChainForAllWindows ? true : (window == bd->Window);
+}
+
+void ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackMousebutton != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackMousebutton(window, button, action, mods);
+
+    ImGui_ImplGlfw_UpdateKeyModifiers(window);
+
+    ImGuiIO& io = ImGui::GetIO();
+    if (button >= 0 && button < ImGuiMouseButton_COUNT)
+        io.AddMouseButtonEvent(button, action == GLFW_PRESS);
+}
+
+void ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackScroll != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackScroll(window, xoffset, yoffset);
+
+#ifdef __EMSCRIPTEN__
+    // Ignore GLFW events: will be processed in ImGui_ImplEmscripten_WheelCallback().
+    return;
+#endif
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMouseWheelEvent((float)xoffset, (float)yoffset);
+}
+
+static int ImGui_ImplGlfw_TranslateUntranslatedKey(int key, int scancode)
+{
+#if GLFW_HAS_GETKEYNAME && !defined(__EMSCRIPTEN__)
+    // GLFW 3.1+ attempts to "untranslate" keys, which goes the opposite of what every other framework does, making using lettered shortcuts difficult.
+    // (It had reasons to do so: namely GLFW is/was more likely to be used for WASD-type game controls rather than lettered shortcuts, but IHMO the 3.1 change could have been done differently)
+    // See https://github.com/glfw/glfw/issues/1502 for details.
+    // Adding a workaround to undo this (so our keys are translated->untranslated->translated, likely a lossy process).
+    // This won't cover edge cases but this is at least going to cover common cases.
+    if (key >= GLFW_KEY_KP_0 && key <= GLFW_KEY_KP_EQUAL)
+        return key;
+    GLFWerrorfun prev_error_callback = glfwSetErrorCallback(nullptr);
+    const char* key_name = glfwGetKeyName(key, scancode);
+    glfwSetErrorCallback(prev_error_callback);
+#if GLFW_HAS_GETERROR && !defined(__EMSCRIPTEN__) // Eat errors (see #5908)
+    (void)glfwGetError(nullptr);
+#endif
+    if (key_name && key_name[0] != 0 && key_name[1] == 0)
+    {
+        const char char_names[] = "`-=[]\\,;\'./";
+        const int char_keys[] = { GLFW_KEY_GRAVE_ACCENT, GLFW_KEY_MINUS, GLFW_KEY_EQUAL, GLFW_KEY_LEFT_BRACKET, GLFW_KEY_RIGHT_BRACKET, GLFW_KEY_BACKSLASH, GLFW_KEY_COMMA, GLFW_KEY_SEMICOLON, GLFW_KEY_APOSTROPHE, GLFW_KEY_PERIOD, GLFW_KEY_SLASH, 0 };
+        IM_ASSERT(IM_ARRAYSIZE(char_names) == IM_ARRAYSIZE(char_keys));
+        if (key_name[0] >= '0' && key_name[0] <= '9')               { key = GLFW_KEY_0 + (key_name[0] - '0'); }
+        else if (key_name[0] >= 'A' && key_name[0] <= 'Z')          { key = GLFW_KEY_A + (key_name[0] - 'A'); }
+        else if (key_name[0] >= 'a' && key_name[0] <= 'z')          { key = GLFW_KEY_A + (key_name[0] - 'a'); }
+        else if (const char* p = strchr(char_names, key_name[0]))   { key = char_keys[p - char_names]; }
+    }
+    // if (action == GLFW_PRESS) printf("key %d scancode %d name '%s'\n", key, scancode, key_name);
+#else
+    IM_UNUSED(scancode);
+#endif
+    return key;
+}
+
+void ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int keycode, int scancode, int action, int mods)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackKey != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackKey(window, keycode, scancode, action, mods);
+
+    if (action != GLFW_PRESS && action != GLFW_RELEASE)
+        return;
+
+    ImGui_ImplGlfw_UpdateKeyModifiers(window);
+
+    keycode = ImGui_ImplGlfw_TranslateUntranslatedKey(keycode, scancode);
+
+    ImGuiIO& io = ImGui::GetIO();
+    ImGuiKey imgui_key = ImGui_ImplGlfw_KeyToImGuiKey(keycode);
+    io.AddKeyEvent(imgui_key, (action == GLFW_PRESS));
+    io.SetKeyEventNativeData(imgui_key, keycode, scancode); // To support legacy indexing (<1.87 user code)
+}
+
+void ImGui_ImplGlfw_WindowFocusCallback(GLFWwindow* window, int focused)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackWindowFocus != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackWindowFocus(window, focused);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddFocusEvent(focused != 0);
+}
+
+void ImGui_ImplGlfw_CursorPosCallback(GLFWwindow* window, double x, double y)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackCursorPos != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackCursorPos(window, x, y);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMousePosEvent((float)x, (float)y);
+    bd->LastValidMousePos = ImVec2((float)x, (float)y);
+}
+
+// Workaround: X11 seems to send spurious Leave/Enter events which would make us lose our position,
+// so we back it up and restore on Leave/Enter (see https://github.com/ocornut/imgui/issues/4984)
+void ImGui_ImplGlfw_CursorEnterCallback(GLFWwindow* window, int entered)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackCursorEnter != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackCursorEnter(window, entered);
+
+    ImGuiIO& io = ImGui::GetIO();
+    if (entered)
+    {
+        bd->MouseWindow = window;
+        io.AddMousePosEvent(bd->LastValidMousePos.x, bd->LastValidMousePos.y);
+    }
+    else if (!entered && bd->MouseWindow == window)
+    {
+        bd->LastValidMousePos = io.MousePos;
+        bd->MouseWindow = nullptr;
+        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+    }
+}
+
+void ImGui_ImplGlfw_CharCallback(GLFWwindow* window, unsigned int c)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if (bd->PrevUserCallbackChar != nullptr && ImGui_ImplGlfw_ShouldChainCallback(window))
+        bd->PrevUserCallbackChar(window, c);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddInputCharacter(c);
+}
+
+void ImGui_ImplGlfw_MonitorCallback(GLFWmonitor*, int)
+{
+	// Unused in 'master' branch but 'docking' branch will use this, so we declare it ahead of it so if you have to install callbacks you can install this one too.
+}
+
+#ifdef __EMSCRIPTEN__
+static EM_BOOL ImGui_ImplEmscripten_WheelCallback(int, const EmscriptenWheelEvent* ev, void*)
+{
+    // Mimic Emscripten_HandleWheel() in SDL.
+    // Corresponding equivalent in GLFW JS emulation layer has incorrect quantizing preventing small values. See #6096
+    float multiplier = 0.0f;
+    if (ev->deltaMode == DOM_DELTA_PIXEL)       { multiplier = 1.0f / 100.0f; } // 100 pixels make up a step.
+    else if (ev->deltaMode == DOM_DELTA_LINE)   { multiplier = 1.0f / 3.0f; }   // 3 lines make up a step.
+    else if (ev->deltaMode == DOM_DELTA_PAGE)   { multiplier = 80.0f; }         // A page makes up 80 steps.
+    float wheel_x = ev->deltaX * -multiplier;
+    float wheel_y = ev->deltaY * -multiplier;
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMouseWheelEvent(wheel_x, wheel_y);
+    //IMGUI_DEBUG_LOG("[Emsc] mode %d dx: %.2f, dy: %.2f, dz: %.2f --> feed %.2f %.2f\n", (int)ev->deltaMode, ev->deltaX, ev->deltaY, ev->deltaZ, wheel_x, wheel_y);
+    return EM_TRUE;
+}
+#endif
+
+#ifdef _WIN32
+// GLFW doesn't allow to distinguish Mouse vs TouchScreen vs Pen.
+// Add support for Win32 (based on imgui_impl_win32), because we rely on _TouchScreen info to trickle inputs differently.
+static ImGuiMouseSource GetMouseSourceFromMessageExtraInfo()
+{
+    LPARAM extra_info = ::GetMessageExtraInfo();
+    if ((extra_info & 0xFFFFFF80) == 0xFF515700)
+        return ImGuiMouseSource_Pen;
+    if ((extra_info & 0xFFFFFF80) == 0xFF515780)
+        return ImGuiMouseSource_TouchScreen;
+    return ImGuiMouseSource_Mouse;
+}
+static LRESULT CALLBACK ImGui_ImplGlfw_WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    switch (msg)
+    {
+    case WM_MOUSEMOVE: case WM_NCMOUSEMOVE:
+    case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK: case WM_LBUTTONUP:
+    case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK: case WM_RBUTTONUP:
+    case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK: case WM_MBUTTONUP:
+    case WM_XBUTTONDOWN: case WM_XBUTTONDBLCLK: case WM_XBUTTONUP:
+        ImGui::GetIO().AddMouseSourceEvent(GetMouseSourceFromMessageExtraInfo());
+        break;
+    }
+    return ::CallWindowProc(bd->GlfwWndProc, hWnd, msg, wParam, lParam);
+}
+#endif
+
+void ImGui_ImplGlfw_InstallCallbacks(GLFWwindow* window)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    IM_ASSERT(bd->InstalledCallbacks == false && "Callbacks already installed!");
+    IM_ASSERT(bd->Window == window);
+
+    bd->PrevUserCallbackWindowFocus = glfwSetWindowFocusCallback(window, ImGui_ImplGlfw_WindowFocusCallback);
+    bd->PrevUserCallbackCursorEnter = glfwSetCursorEnterCallback(window, ImGui_ImplGlfw_CursorEnterCallback);
+    bd->PrevUserCallbackCursorPos = glfwSetCursorPosCallback(window, ImGui_ImplGlfw_CursorPosCallback);
+    bd->PrevUserCallbackMousebutton = glfwSetMouseButtonCallback(window, ImGui_ImplGlfw_MouseButtonCallback);
+    bd->PrevUserCallbackScroll = glfwSetScrollCallback(window, ImGui_ImplGlfw_ScrollCallback);
+    bd->PrevUserCallbackKey = glfwSetKeyCallback(window, ImGui_ImplGlfw_KeyCallback);
+    bd->PrevUserCallbackChar = glfwSetCharCallback(window, ImGui_ImplGlfw_CharCallback);
+    bd->PrevUserCallbackMonitor = glfwSetMonitorCallback(ImGui_ImplGlfw_MonitorCallback);
+    bd->InstalledCallbacks = true;
+}
+
+void ImGui_ImplGlfw_RestoreCallbacks(GLFWwindow* window)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    IM_ASSERT(bd->InstalledCallbacks == true && "Callbacks not installed!");
+    IM_ASSERT(bd->Window == window);
+
+    glfwSetWindowFocusCallback(window, bd->PrevUserCallbackWindowFocus);
+    glfwSetCursorEnterCallback(window, bd->PrevUserCallbackCursorEnter);
+    glfwSetCursorPosCallback(window, bd->PrevUserCallbackCursorPos);
+    glfwSetMouseButtonCallback(window, bd->PrevUserCallbackMousebutton);
+    glfwSetScrollCallback(window, bd->PrevUserCallbackScroll);
+    glfwSetKeyCallback(window, bd->PrevUserCallbackKey);
+    glfwSetCharCallback(window, bd->PrevUserCallbackChar);
+    glfwSetMonitorCallback(bd->PrevUserCallbackMonitor);
+    bd->InstalledCallbacks = false;
+    bd->PrevUserCallbackWindowFocus = nullptr;
+    bd->PrevUserCallbackCursorEnter = nullptr;
+    bd->PrevUserCallbackCursorPos = nullptr;
+    bd->PrevUserCallbackMousebutton = nullptr;
+    bd->PrevUserCallbackScroll = nullptr;
+    bd->PrevUserCallbackKey = nullptr;
+    bd->PrevUserCallbackChar = nullptr;
+    bd->PrevUserCallbackMonitor = nullptr;
+}
+
+// Set to 'true' to enable chaining installed callbacks for all windows (including secondary viewports created by backends or by user.
+// This is 'false' by default meaning we only chain callbacks for the main viewport.
+// We cannot set this to 'true' by default because user callbacks code may be not testing the 'window' parameter of their callback.
+// If you set this to 'true' your user callback code will need to make sure you are testing the 'window' parameter.
+void ImGui_ImplGlfw_SetCallbacksChainForAllWindows(bool chain_for_all_windows)
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    bd->CallbacksChainForAllWindows = chain_for_all_windows;
+}
+
+static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, GlfwClientApi client_api)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+    //printf("GLFW_VERSION: %d.%d.%d (%d)", GLFW_VERSION_MAJOR, GLFW_VERSION_MINOR, GLFW_VERSION_REVISION, GLFW_VERSION_COMBINED);
+
+    // Setup backend capabilities flags
+    ImGui_ImplGlfw_Data* bd = IM_NEW(ImGui_ImplGlfw_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = "imgui_impl_glfw";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;         // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+
+    bd->Window = window;
+    bd->Time = 0.0;
+
+    io.SetClipboardTextFn = ImGui_ImplGlfw_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplGlfw_GetClipboardText;
+    io.ClipboardUserData = bd->Window;
+
+    // Create mouse cursors
+    // (By design, on X11 cursors are user configurable and some cursors may be missing. When a cursor doesn't exist,
+    // GLFW will emit an error which will often be printed by the app, so we temporarily disable error reporting.
+    // Missing cursors will return nullptr and our _UpdateMouseCursor() function will use the Arrow cursor instead.)
+    GLFWerrorfun prev_error_callback = glfwSetErrorCallback(nullptr);
+    bd->MouseCursors[ImGuiMouseCursor_Arrow] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_TextInput] = glfwCreateStandardCursor(GLFW_IBEAM_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNS] = glfwCreateStandardCursor(GLFW_VRESIZE_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeEW] = glfwCreateStandardCursor(GLFW_HRESIZE_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_Hand] = glfwCreateStandardCursor(GLFW_HAND_CURSOR);
+#if GLFW_HAS_NEW_CURSORS
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = glfwCreateStandardCursor(GLFW_RESIZE_ALL_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = glfwCreateStandardCursor(GLFW_RESIZE_NESW_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = glfwCreateStandardCursor(GLFW_RESIZE_NWSE_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = glfwCreateStandardCursor(GLFW_NOT_ALLOWED_CURSOR);
+#else
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+#endif
+    glfwSetErrorCallback(prev_error_callback);
+#if GLFW_HAS_GETERROR && !defined(__EMSCRIPTEN__) // Eat errors (see #5908)
+    (void)glfwGetError(nullptr);
+#endif
+
+    // Chain GLFW callbacks: our callbacks will call the user's previously installed callbacks, if any.
+    if (install_callbacks)
+        ImGui_ImplGlfw_InstallCallbacks(window);
+    // Register Emscripten Wheel callback to workaround issue in Emscripten GLFW Emulation (#6096)
+    // We intentionally do not check 'if (install_callbacks)' here, as some users may set it to false and call GLFW callback themselves.
+    // FIXME: May break chaining in case user registered their own Emscripten callback?
+#ifdef __EMSCRIPTEN__
+    emscripten_set_wheel_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, nullptr, false, ImGui_ImplEmscripten_WheelCallback);
+#endif
+
+    // Set platform dependent data in viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+#ifdef _WIN32
+    main_viewport->PlatformHandleRaw = glfwGetWin32Window(bd->Window);
+#elif defined(__APPLE__)
+    main_viewport->PlatformHandleRaw = (void*)glfwGetCocoaWindow(bd->Window);
+#else
+    IM_UNUSED(main_viewport);
+#endif
+
+    // Windows: register a WndProc hook so we can intercept some messages.
+#ifdef _WIN32
+    bd->GlfwWndProc = (WNDPROC)::GetWindowLongPtr((HWND)main_viewport->PlatformHandleRaw, GWLP_WNDPROC);
+    IM_ASSERT(bd->GlfwWndProc != nullptr);
+    ::SetWindowLongPtr((HWND)main_viewport->PlatformHandleRaw, GWLP_WNDPROC, (LONG_PTR)ImGui_ImplGlfw_WndProc);
+#endif
+
+    bd->ClientApi = client_api;
+    return true;
+}
+
+bool ImGui_ImplGlfw_InitForOpenGL(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_OpenGL);
+}
+
+bool ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_Vulkan);
+}
+
+bool ImGui_ImplGlfw_InitForOther(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_Unknown);
+}
+
+void ImGui_ImplGlfw_Shutdown()
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    if (bd->InstalledCallbacks)
+        ImGui_ImplGlfw_RestoreCallbacks(bd->Window);
+#ifdef __EMSCRIPTEN__
+    emscripten_set_wheel_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, nullptr, false, nullptr);
+#endif
+
+    for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
+        glfwDestroyCursor(bd->MouseCursors[cursor_n]);
+
+    // Windows: register a WndProc hook so we can intercept some messages.
+#ifdef _WIN32
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ::SetWindowLongPtr((HWND)main_viewport->PlatformHandleRaw, GWLP_WNDPROC, (LONG_PTR)bd->GlfwWndProc);
+    bd->GlfwWndProc = nullptr;
+#endif
+
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplGlfw_UpdateMouseData()
+{
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+
+    // (those braces are here to reduce diff with multi-viewports support in 'docking' branch)
+    {
+        GLFWwindow* window = bd->Window;
+
+#ifdef __EMSCRIPTEN__
+        const bool is_window_focused = true;
+#else
+        const bool is_window_focused = glfwGetWindowAttrib(window, GLFW_FOCUSED) != 0;
+#endif
+        if (is_window_focused)
+        {
+            // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+            if (io.WantSetMousePos)
+                glfwSetCursorPos(window, (double)io.MousePos.x, (double)io.MousePos.y);
+
+            // (Optional) Fallback to provide mouse position when focused (ImGui_ImplGlfw_CursorPosCallback already provides this when hovered or captured)
+            if (bd->MouseWindow == nullptr)
+            {
+                double mouse_x, mouse_y;
+                glfwGetCursorPos(window, &mouse_x, &mouse_y);
+                bd->LastValidMousePos = ImVec2((float)mouse_x, (float)mouse_y);
+                io.AddMousePosEvent((float)mouse_x, (float)mouse_y);
+            }
+        }
+    }
+}
+
+static void ImGui_ImplGlfw_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange) || glfwGetInputMode(bd->Window, GLFW_CURSOR) == GLFW_CURSOR_DISABLED)
+        return;
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    // (those braces are here to reduce diff with multi-viewports support in 'docking' branch)
+    {
+        GLFWwindow* window = bd->Window;
+        if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
+        {
+            // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+            glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
+        }
+        else
+        {
+            // Show OS mouse cursor
+            // FIXME-PLATFORM: Unfocused windows seems to fail changing the mouse cursor with GLFW 3.2, but 3.3 works here.
+            glfwSetCursor(window, bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow]);
+            glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
+        }
+    }
+}
+
+// Update gamepad inputs
+static inline float Saturate(float v) { return v < 0.0f ? 0.0f : v  > 1.0f ? 1.0f : v; }
+static void ImGui_ImplGlfw_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+        return;
+
+    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+#if GLFW_HAS_GAMEPAD_API && !defined(__EMSCRIPTEN__)
+    GLFWgamepadstate gamepad;
+    if (!glfwGetGamepadState(GLFW_JOYSTICK_1, &gamepad))
+        return;
+    #define MAP_BUTTON(KEY_NO, BUTTON_NO, _UNUSED)          do { io.AddKeyEvent(KEY_NO, gamepad.buttons[BUTTON_NO] != 0); } while (0)
+    #define MAP_ANALOG(KEY_NO, AXIS_NO, _UNUSED, V0, V1)    do { float v = gamepad.axes[AXIS_NO]; v = (v - V0) / (V1 - V0); io.AddKeyAnalogEvent(KEY_NO, v > 0.10f, Saturate(v)); } while (0)
+#else
+    int axes_count = 0, buttons_count = 0;
+    const float* axes = glfwGetJoystickAxes(GLFW_JOYSTICK_1, &axes_count);
+    const unsigned char* buttons = glfwGetJoystickButtons(GLFW_JOYSTICK_1, &buttons_count);
+    if (axes_count == 0 || buttons_count == 0)
+        return;
+    #define MAP_BUTTON(KEY_NO, _UNUSED, BUTTON_NO)          do { io.AddKeyEvent(KEY_NO, (buttons_count > BUTTON_NO && buttons[BUTTON_NO] == GLFW_PRESS)); } while (0)
+    #define MAP_ANALOG(KEY_NO, _UNUSED, AXIS_NO, V0, V1)    do { float v = (axes_count > AXIS_NO) ? axes[AXIS_NO] : V0; v = (v - V0) / (V1 - V0); io.AddKeyAnalogEvent(KEY_NO, v > 0.10f, Saturate(v)); } while (0)
+#endif
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+    MAP_BUTTON(ImGuiKey_GamepadStart,       GLFW_GAMEPAD_BUTTON_START,          7);
+    MAP_BUTTON(ImGuiKey_GamepadBack,        GLFW_GAMEPAD_BUTTON_BACK,           6);
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,    GLFW_GAMEPAD_BUTTON_X,              2);     // Xbox X, PS Square
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,   GLFW_GAMEPAD_BUTTON_B,              1);     // Xbox B, PS Circle
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,      GLFW_GAMEPAD_BUTTON_Y,              3);     // Xbox Y, PS Triangle
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,    GLFW_GAMEPAD_BUTTON_A,              0);     // Xbox A, PS Cross
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,    GLFW_GAMEPAD_BUTTON_DPAD_LEFT,      13);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,   GLFW_GAMEPAD_BUTTON_DPAD_RIGHT,     11);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,      GLFW_GAMEPAD_BUTTON_DPAD_UP,        10);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,    GLFW_GAMEPAD_BUTTON_DPAD_DOWN,      12);
+    MAP_BUTTON(ImGuiKey_GamepadL1,          GLFW_GAMEPAD_BUTTON_LEFT_BUMPER,    4);
+    MAP_BUTTON(ImGuiKey_GamepadR1,          GLFW_GAMEPAD_BUTTON_RIGHT_BUMPER,   5);
+    MAP_ANALOG(ImGuiKey_GamepadL2,          GLFW_GAMEPAD_AXIS_LEFT_TRIGGER,     4,      -0.75f,  +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadR2,          GLFW_GAMEPAD_AXIS_RIGHT_TRIGGER,    5,      -0.75f,  +1.0f);
+    MAP_BUTTON(ImGuiKey_GamepadL3,          GLFW_GAMEPAD_BUTTON_LEFT_THUMB,     8);
+    MAP_BUTTON(ImGuiKey_GamepadR3,          GLFW_GAMEPAD_BUTTON_RIGHT_THUMB,    9);
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,  GLFW_GAMEPAD_AXIS_LEFT_X,           0,      -0.25f,  -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight, GLFW_GAMEPAD_AXIS_LEFT_X,           0,      +0.25f,  +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,    GLFW_GAMEPAD_AXIS_LEFT_Y,           1,      -0.25f,  -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,  GLFW_GAMEPAD_AXIS_LEFT_Y,           1,      +0.25f,  +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,  GLFW_GAMEPAD_AXIS_RIGHT_X,          2,      -0.25f,  -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight, GLFW_GAMEPAD_AXIS_RIGHT_X,          2,      +0.25f,  +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,    GLFW_GAMEPAD_AXIS_RIGHT_Y,          3,      -0.25f,  -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,  GLFW_GAMEPAD_AXIS_RIGHT_Y,          3,      +0.25f,  +1.0f);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+}
+
+void ImGui_ImplGlfw_NewFrame()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplGlfw_InitForXXX()?");
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    int display_w, display_h;
+    glfwGetWindowSize(bd->Window, &w, &h);
+    glfwGetFramebufferSize(bd->Window, &display_w, &display_h);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+    if (w > 0 && h > 0)
+        io.DisplayFramebufferScale = ImVec2((float)display_w / (float)w, (float)display_h / (float)h);
+
+    // Setup time step
+    // (Accept glfwGetTime() not returning a monotonically increasing value. Seems to happens on disconnecting peripherals and probably on VMs and Emscripten, see #6491, #6189, #6114, #3644)
+    double current_time = glfwGetTime();
+    if (current_time <= bd->Time)
+        current_time = bd->Time + 0.00001f;
+    io.DeltaTime = bd->Time > 0.0 ? (float)(current_time - bd->Time) : (float)(1.0f / 60.0f);
+    bd->Time = current_time;
+
+    ImGui_ImplGlfw_UpdateMouseData();
+    ImGui_ImplGlfw_UpdateMouseCursor();
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplGlfw_UpdateGamepads();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_glfw.h

@@ -0,0 +1,53 @@
+// dear imgui: Platform Backend for GLFW
+// This needs to be used along with a Renderer (e.g. OpenGL3, Vulkan, WebGPU..)
+// (Info: GLFW is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen (Windows only).
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLFW_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange' (note: the resizing cursors requires GLFW 3.4+).
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct GLFWwindow;
+struct GLFWmonitor;
+
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOpenGL(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOther(GLFWwindow* window, bool install_callbacks);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplGlfw_NewFrame();
+
+// GLFW callbacks install
+// - When calling Init with 'install_callbacks=true': ImGui_ImplGlfw_InstallCallbacks() is called. GLFW callbacks will be installed for you. They will chain-call user's previously installed callbacks, if any.
+// - When calling Init with 'install_callbacks=false': GLFW callbacks won't be installed. You will need to call individual function yourself from your own GLFW callbacks.
+IMGUI_IMPL_API void     ImGui_ImplGlfw_InstallCallbacks(GLFWwindow* window);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_RestoreCallbacks(GLFWwindow* window);
+
+// GFLW callbacks options:
+// - Set 'chain_for_all_windows=true' to enable chaining callbacks for all windows (including secondary viewports created by backends or by user)
+IMGUI_IMPL_API void     ImGui_ImplGlfw_SetCallbacksChainForAllWindows(bool chain_for_all_windows);
+
+// GLFW callbacks (individual callbacks to call yourself if you didn't install callbacks)
+IMGUI_IMPL_API void     ImGui_ImplGlfw_WindowFocusCallback(GLFWwindow* window, int focused);        // Since 1.84
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CursorEnterCallback(GLFWwindow* window, int entered);        // Since 1.84
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CursorPosCallback(GLFWwindow* window, double x, double y);   // Since 1.87
+IMGUI_IMPL_API void     ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_CharCallback(GLFWwindow* window, unsigned int c);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_MonitorCallback(GLFWmonitor* monitor, int event);
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_glut.cpp

@@ -0,0 +1,308 @@
+// dear imgui: Platform Backend for GLUT/FreeGLUT
+// This needs to be used along with a Renderer (e.g. OpenGL2)
+
+// !!! GLUT/FreeGLUT IS OBSOLETE PREHISTORIC SOFTWARE. Using GLUT is not recommended unless you really miss the 90's. !!!
+// !!! If someone or something is teaching you GLUT today, you are being abused. Please show some resistance. !!!
+// !!! Nowadays, prefer using GLFW or SDL instead!
+
+// Implemented features:
+//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+// Issues:
+//  [ ] Platform: GLUT is unable to distinguish e.g. Backspace from CTRL+H or TAB from CTRL+I
+//  [ ] Platform: Missing horizontal mouse wheel support.
+//  [ ] Platform: Missing mouse cursor shape/visibility support.
+//  [ ] Platform: Missing clipboard support (not supported by Glut).
+//  [ ] Platform: Missing gamepad support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-04-17: BREAKING: Removed call to ImGui::NewFrame() from ImGui_ImplGLUT_NewFrame(). Needs to be called from the main application loop, like with every other backends.
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2019-04-03: Misc: Renamed imgui_impl_freeglut.cpp/.h to imgui_impl_glut.cpp/.h.
+//  2019-03-25: Misc: Made io.DeltaTime always above zero.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-03-22: Added GLUT Platform binding.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_glut.h"
+#define GL_SILENCE_DEPRECATION
+#ifdef __APPLE__
+#include <GLUT/glut.h>
+#else
+#include <GL/freeglut.h>
+#endif
+
+#ifdef _MSC_VER
+#pragma warning (disable: 4505) // unreferenced local function has been removed (stb stuff)
+#endif
+
+static int g_Time = 0;          // Current time, in milliseconds
+
+// Glut has 1 function for characters and one for "special keys". We map the characters in the 0..255 range and the keys above.
+static ImGuiKey ImGui_ImplGLUT_KeyToImGuiKey(int key)
+{
+    switch (key)
+    {
+        case '\t':                      return ImGuiKey_Tab;
+        case 256 + GLUT_KEY_LEFT:       return ImGuiKey_LeftArrow;
+        case 256 + GLUT_KEY_RIGHT:      return ImGuiKey_RightArrow;
+        case 256 + GLUT_KEY_UP:         return ImGuiKey_UpArrow;
+        case 256 + GLUT_KEY_DOWN:       return ImGuiKey_DownArrow;
+        case 256 + GLUT_KEY_PAGE_UP:    return ImGuiKey_PageUp;
+        case 256 + GLUT_KEY_PAGE_DOWN:  return ImGuiKey_PageDown;
+        case 256 + GLUT_KEY_HOME:       return ImGuiKey_Home;
+        case 256 + GLUT_KEY_END:        return ImGuiKey_End;
+        case 256 + GLUT_KEY_INSERT:     return ImGuiKey_Insert;
+        case 127:                       return ImGuiKey_Delete;
+        case 8:                         return ImGuiKey_Backspace;
+        case ' ':                       return ImGuiKey_Space;
+        case 13:                        return ImGuiKey_Enter;
+        case 27:                        return ImGuiKey_Escape;
+        case 39:                        return ImGuiKey_Apostrophe;
+        case 44:                        return ImGuiKey_Comma;
+        case 45:                        return ImGuiKey_Minus;
+        case 46:                        return ImGuiKey_Period;
+        case 47:                        return ImGuiKey_Slash;
+        case 59:                        return ImGuiKey_Semicolon;
+        case 61:                        return ImGuiKey_Equal;
+        case 91:                        return ImGuiKey_LeftBracket;
+        case 92:                        return ImGuiKey_Backslash;
+        case 93:                        return ImGuiKey_RightBracket;
+        case 96:                        return ImGuiKey_GraveAccent;
+        //case 0:                         return ImGuiKey_CapsLock;
+        //case 0:                         return ImGuiKey_ScrollLock;
+        case 256 + 0x006D:              return ImGuiKey_NumLock;
+        //case 0:                         return ImGuiKey_PrintScreen;
+        //case 0:                         return ImGuiKey_Pause;
+        //case '0':                       return ImGuiKey_Keypad0;
+        //case '1':                       return ImGuiKey_Keypad1;
+        //case '2':                       return ImGuiKey_Keypad2;
+        //case '3':                       return ImGuiKey_Keypad3;
+        //case '4':                       return ImGuiKey_Keypad4;
+        //case '5':                       return ImGuiKey_Keypad5;
+        //case '6':                       return ImGuiKey_Keypad6;
+        //case '7':                       return ImGuiKey_Keypad7;
+        //case '8':                       return ImGuiKey_Keypad8;
+        //case '9':                       return ImGuiKey_Keypad9;
+        //case 46:                        return ImGuiKey_KeypadDecimal;
+        //case 47:                        return ImGuiKey_KeypadDivide;
+        case 42:                        return ImGuiKey_KeypadMultiply;
+        //case 45:                        return ImGuiKey_KeypadSubtract;
+        case 43:                        return ImGuiKey_KeypadAdd;
+        //case 13:                        return ImGuiKey_KeypadEnter;
+        //case 0:                         return ImGuiKey_KeypadEqual;
+        case 256 + 0x0072:              return ImGuiKey_LeftCtrl;
+        case 256 + 0x0070:              return ImGuiKey_LeftShift;
+        case 256 + 0x0074:              return ImGuiKey_LeftAlt;
+        //case 0:                         return ImGuiKey_LeftSuper;
+        case 256 + 0x0073:              return ImGuiKey_RightCtrl;
+        case 256 + 0x0071:              return ImGuiKey_RightShift;
+        case 256 + 0x0075:              return ImGuiKey_RightAlt;
+        //case 0:                         return ImGuiKey_RightSuper;
+        //case 0:                         return ImGuiKey_Menu;
+        case '0':                       return ImGuiKey_0;
+        case '1':                       return ImGuiKey_1;
+        case '2':                       return ImGuiKey_2;
+        case '3':                       return ImGuiKey_3;
+        case '4':                       return ImGuiKey_4;
+        case '5':                       return ImGuiKey_5;
+        case '6':                       return ImGuiKey_6;
+        case '7':                       return ImGuiKey_7;
+        case '8':                       return ImGuiKey_8;
+        case '9':                       return ImGuiKey_9;
+        case 'A': case 'a':             return ImGuiKey_A;
+        case 'B': case 'b':             return ImGuiKey_B;
+        case 'C': case 'c':             return ImGuiKey_C;
+        case 'D': case 'd':             return ImGuiKey_D;
+        case 'E': case 'e':             return ImGuiKey_E;
+        case 'F': case 'f':             return ImGuiKey_F;
+        case 'G': case 'g':             return ImGuiKey_G;
+        case 'H': case 'h':             return ImGuiKey_H;
+        case 'I': case 'i':             return ImGuiKey_I;
+        case 'J': case 'j':             return ImGuiKey_J;
+        case 'K': case 'k':             return ImGuiKey_K;
+        case 'L': case 'l':             return ImGuiKey_L;
+        case 'M': case 'm':             return ImGuiKey_M;
+        case 'N': case 'n':             return ImGuiKey_N;
+        case 'O': case 'o':             return ImGuiKey_O;
+        case 'P': case 'p':             return ImGuiKey_P;
+        case 'Q': case 'q':             return ImGuiKey_Q;
+        case 'R': case 'r':             return ImGuiKey_R;
+        case 'S': case 's':             return ImGuiKey_S;
+        case 'T': case 't':             return ImGuiKey_T;
+        case 'U': case 'u':             return ImGuiKey_U;
+        case 'V': case 'v':             return ImGuiKey_V;
+        case 'W': case 'w':             return ImGuiKey_W;
+        case 'X': case 'x':             return ImGuiKey_X;
+        case 'Y': case 'y':             return ImGuiKey_Y;
+        case 'Z': case 'z':             return ImGuiKey_Z;
+        case 256 + GLUT_KEY_F1:         return ImGuiKey_F1;
+        case 256 + GLUT_KEY_F2:         return ImGuiKey_F2;
+        case 256 + GLUT_KEY_F3:         return ImGuiKey_F3;
+        case 256 + GLUT_KEY_F4:         return ImGuiKey_F4;
+        case 256 + GLUT_KEY_F5:         return ImGuiKey_F5;
+        case 256 + GLUT_KEY_F6:         return ImGuiKey_F6;
+        case 256 + GLUT_KEY_F7:         return ImGuiKey_F7;
+        case 256 + GLUT_KEY_F8:         return ImGuiKey_F8;
+        case 256 + GLUT_KEY_F9:         return ImGuiKey_F9;
+        case 256 + GLUT_KEY_F10:        return ImGuiKey_F10;
+        case 256 + GLUT_KEY_F11:        return ImGuiKey_F11;
+        case 256 + GLUT_KEY_F12:        return ImGuiKey_F12;
+        default:                        return ImGuiKey_None;
+    }
+}
+
+bool ImGui_ImplGLUT_Init()
+{
+    ImGuiIO& io = ImGui::GetIO();
+
+#ifdef FREEGLUT
+    io.BackendPlatformName = "imgui_impl_glut (freeglut)";
+#else
+    io.BackendPlatformName = "imgui_impl_glut";
+#endif
+    g_Time = 0;
+
+    return true;
+}
+
+void ImGui_ImplGLUT_InstallFuncs()
+{
+    glutReshapeFunc(ImGui_ImplGLUT_ReshapeFunc);
+    glutMotionFunc(ImGui_ImplGLUT_MotionFunc);
+    glutPassiveMotionFunc(ImGui_ImplGLUT_MotionFunc);
+    glutMouseFunc(ImGui_ImplGLUT_MouseFunc);
+#ifdef __FREEGLUT_EXT_H__
+    glutMouseWheelFunc(ImGui_ImplGLUT_MouseWheelFunc);
+#endif
+    glutKeyboardFunc(ImGui_ImplGLUT_KeyboardFunc);
+    glutKeyboardUpFunc(ImGui_ImplGLUT_KeyboardUpFunc);
+    glutSpecialFunc(ImGui_ImplGLUT_SpecialFunc);
+    glutSpecialUpFunc(ImGui_ImplGLUT_SpecialUpFunc);
+}
+
+void ImGui_ImplGLUT_Shutdown()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendPlatformName = nullptr;
+}
+
+void ImGui_ImplGLUT_NewFrame()
+{
+    // Setup time step
+    ImGuiIO& io = ImGui::GetIO();
+    int current_time = glutGet(GLUT_ELAPSED_TIME);
+    int delta_time_ms = (current_time - g_Time);
+    if (delta_time_ms <= 0)
+        delta_time_ms = 1;
+    io.DeltaTime = delta_time_ms / 1000.0f;
+    g_Time = current_time;
+}
+
+static void ImGui_ImplGLUT_UpdateKeyModifiers()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    int glut_key_mods = glutGetModifiers();
+    io.AddKeyEvent(ImGuiMod_Ctrl, (glut_key_mods & GLUT_ACTIVE_CTRL) != 0);
+    io.AddKeyEvent(ImGuiMod_Shift, (glut_key_mods & GLUT_ACTIVE_SHIFT) != 0);
+    io.AddKeyEvent(ImGuiMod_Alt, (glut_key_mods & GLUT_ACTIVE_ALT) != 0);
+}
+
+static void ImGui_ImplGLUT_AddKeyEvent(ImGuiKey key, bool down, int native_keycode)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(key, down);
+    io.SetKeyEventNativeData(key, native_keycode, -1); // To support legacy indexing (<1.87 user code)
+}
+
+void ImGui_ImplGLUT_KeyboardFunc(unsigned char c, int x, int y)
+{
+    // Send character to imgui
+    //printf("char_down_func %d '%c'\n", c, c);
+    ImGuiIO& io = ImGui::GetIO();
+    if (c >= 32)
+        io.AddInputCharacter((unsigned int)c);
+
+    ImGuiKey key = ImGui_ImplGLUT_KeyToImGuiKey(c);
+    ImGui_ImplGLUT_AddKeyEvent(key, true, c);
+    ImGui_ImplGLUT_UpdateKeyModifiers();
+    (void)x; (void)y; // Unused
+}
+
+void ImGui_ImplGLUT_KeyboardUpFunc(unsigned char c, int x, int y)
+{
+    //printf("char_up_func %d '%c'\n", c, c);
+    ImGuiKey key = ImGui_ImplGLUT_KeyToImGuiKey(c);
+    ImGui_ImplGLUT_AddKeyEvent(key, false, c);
+    ImGui_ImplGLUT_UpdateKeyModifiers();
+    (void)x; (void)y; // Unused
+}
+
+void ImGui_ImplGLUT_SpecialFunc(int key, int x, int y)
+{
+    //printf("key_down_func %d\n", key);
+    ImGuiKey imgui_key = ImGui_ImplGLUT_KeyToImGuiKey(key + 256);
+    ImGui_ImplGLUT_AddKeyEvent(imgui_key, true, key + 256);
+    ImGui_ImplGLUT_UpdateKeyModifiers();
+    (void)x; (void)y; // Unused
+}
+
+void ImGui_ImplGLUT_SpecialUpFunc(int key, int x, int y)
+{
+    //printf("key_up_func %d\n", key);
+    ImGuiKey imgui_key = ImGui_ImplGLUT_KeyToImGuiKey(key + 256);
+    ImGui_ImplGLUT_AddKeyEvent(imgui_key, false, key + 256);
+    ImGui_ImplGLUT_UpdateKeyModifiers();
+    (void)x; (void)y; // Unused
+}
+
+void ImGui_ImplGLUT_MouseFunc(int glut_button, int state, int x, int y)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMousePosEvent((float)x, (float)y);
+    int button = -1;
+    if (glut_button == GLUT_LEFT_BUTTON) button = 0;
+    if (glut_button == GLUT_RIGHT_BUTTON) button = 1;
+    if (glut_button == GLUT_MIDDLE_BUTTON) button = 2;
+    if (button != -1 && (state == GLUT_DOWN || state == GLUT_UP))
+        io.AddMouseButtonEvent(button, state == GLUT_DOWN);
+}
+
+#ifdef __FREEGLUT_EXT_H__
+void ImGui_ImplGLUT_MouseWheelFunc(int button, int dir, int x, int y)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMousePosEvent((float)x, (float)y);
+    if (dir != 0)
+        io.AddMouseWheelEvent(0.0f, dir > 0 ? 1.0f : -1.0f);
+    (void)button; // Unused
+}
+#endif
+
+void ImGui_ImplGLUT_ReshapeFunc(int w, int h)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.DisplaySize = ImVec2((float)w, (float)h);
+}
+
+void ImGui_ImplGLUT_MotionFunc(int x, int y)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMousePosEvent((float)x, (float)y);
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_glut.h

@@ -0,0 +1,46 @@
+// dear imgui: Platform Backend for GLUT/FreeGLUT
+// This needs to be used along with a Renderer (e.g. OpenGL2)
+
+// !!! GLUT/FreeGLUT IS OBSOLETE PREHISTORIC SOFTWARE. Using GLUT is not recommended unless you really miss the 90's. !!!
+// !!! If someone or something is teaching you GLUT today, you are being abused. Please show some resistance. !!!
+// !!! Nowadays, prefer using GLFW or SDL instead!
+
+// Implemented features:
+//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+// Issues:
+//  [ ] Platform: GLUT is unable to distinguish e.g. Backspace from CTRL+H or TAB from CTRL+I
+//  [ ] Platform: Missing horizontal mouse wheel support.
+//  [ ] Platform: Missing mouse cursor shape/visibility support.
+//  [ ] Platform: Missing clipboard support (not supported by Glut).
+//  [ ] Platform: Missing gamepad support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#ifndef IMGUI_DISABLE
+#include "imgui.h"      // IMGUI_IMPL_API
+
+IMGUI_IMPL_API bool     ImGui_ImplGLUT_Init();
+IMGUI_IMPL_API void     ImGui_ImplGLUT_InstallFuncs();
+IMGUI_IMPL_API void     ImGui_ImplGLUT_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplGLUT_NewFrame();
+
+// You can call ImGui_ImplGLUT_InstallFuncs() to get all those functions installed automatically,
+// or call them yourself from your own GLUT handlers. We are using the same weird names as GLUT for consistency..
+//------------------------------------ GLUT name ---------------------------------------------- Decent Name ---------
+IMGUI_IMPL_API void     ImGui_ImplGLUT_ReshapeFunc(int w, int h);                           // ~ ResizeFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_MotionFunc(int x, int y);                            // ~ MouseMoveFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_MouseFunc(int button, int state, int x, int y);      // ~ MouseButtonFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_MouseWheelFunc(int button, int dir, int x, int y);   // ~ MouseWheelFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_KeyboardFunc(unsigned char c, int x, int y);         // ~ CharPressedFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_KeyboardUpFunc(unsigned char c, int x, int y);       // ~ CharReleasedFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_SpecialFunc(int key, int x, int y);                  // ~ KeyPressedFunc
+IMGUI_IMPL_API void     ImGui_ImplGLUT_SpecialUpFunc(int key, int x, int y);                // ~ KeyReleasedFunc
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_metal.h

@@ -0,0 +1,72 @@
+// dear imgui: Renderer Backend for Metal
+// This needs to be used along with a Platform Backend (e.g. OSX)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+//-----------------------------------------------------------------------------
+// ObjC API
+//-----------------------------------------------------------------------------
+
+#ifdef __OBJC__
+
+@class MTLRenderPassDescriptor;
+@protocol MTLDevice, MTLCommandBuffer, MTLRenderCommandEncoder;
+
+IMGUI_IMPL_API bool ImGui_ImplMetal_Init(id<MTLDevice> device);
+IMGUI_IMPL_API void ImGui_ImplMetal_Shutdown();
+IMGUI_IMPL_API void ImGui_ImplMetal_NewFrame(MTLRenderPassDescriptor* renderPassDescriptor);
+IMGUI_IMPL_API void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData,
+                                                   id<MTLCommandBuffer> commandBuffer,
+                                                   id<MTLRenderCommandEncoder> commandEncoder);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool ImGui_ImplMetal_CreateFontsTexture(id<MTLDevice> device);
+IMGUI_IMPL_API void ImGui_ImplMetal_DestroyFontsTexture();
+IMGUI_IMPL_API bool ImGui_ImplMetal_CreateDeviceObjects(id<MTLDevice> device);
+IMGUI_IMPL_API void ImGui_ImplMetal_DestroyDeviceObjects();
+
+#endif
+
+//-----------------------------------------------------------------------------
+// C++ API
+//-----------------------------------------------------------------------------
+
+// Enable Metal C++ binding support with '#define IMGUI_IMPL_METAL_CPP' in your imconfig.h file
+// More info about using Metal from C++: https://developer.apple.com/metal/cpp/
+
+#ifdef IMGUI_IMPL_METAL_CPP
+#include <Metal/Metal.hpp>
+#ifndef __OBJC__
+
+IMGUI_IMPL_API bool ImGui_ImplMetal_Init(MTL::Device* device);
+IMGUI_IMPL_API void ImGui_ImplMetal_Shutdown();
+IMGUI_IMPL_API void ImGui_ImplMetal_NewFrame(MTL::RenderPassDescriptor* renderPassDescriptor);
+IMGUI_IMPL_API void ImGui_ImplMetal_RenderDrawData(ImDrawData* draw_data,
+                                                   MTL::CommandBuffer* commandBuffer,
+                                                   MTL::RenderCommandEncoder* commandEncoder);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool ImGui_ImplMetal_CreateFontsTexture(MTL::Device* device);
+IMGUI_IMPL_API void ImGui_ImplMetal_DestroyFontsTexture();
+IMGUI_IMPL_API bool ImGui_ImplMetal_CreateDeviceObjects(MTL::Device* device);
+IMGUI_IMPL_API void ImGui_ImplMetal_DestroyDeviceObjects();
+
+#endif
+#endif
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_metal.mm

@@ -0,0 +1,590 @@
+// dear imgui: Renderer Backend for Metal
+// This needs to be used along with a Platform Backend (e.g. OSX)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-08-23: Metal: Update deprecated property 'sampleCount'->'rasterSampleCount'.
+//  2022-07-05: Metal: Add dispatch synchronization.
+//  2022-06-30: Metal: Use __bridge for ARC based systems.
+//  2022-06-01: Metal: Fixed null dereference on exit inside command buffer completion handler.
+//  2022-04-27: Misc: Store backend data in a per-context struct, allowing to use this backend with multiple contexts.
+//  2022-01-03: Metal: Ignore ImDrawCmd where ElemCount == 0 (very rare but can technically be manufactured by user code).
+//  2021-12-30: Metal: Added Metal C++ support. Enable with '#define IMGUI_IMPL_METAL_CPP' in your imconfig.h file.
+//  2021-08-24: Metal: Fixed a crash when clipping rect larger than framebuffer is submitted. (#4464)
+//  2021-05-19: Metal: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-02-18: Metal: Change blending equation to preserve alpha in output buffer.
+//  2021-01-25: Metal: Fixed texture storage mode when building on Mac Catalyst.
+//  2019-05-29: Metal: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: Metal: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2019-02-11: Metal: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-07-05: Metal: Added new Metal backend implementation.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_metal.h"
+#import <time.h>
+#import <Metal/Metal.h>
+
+#pragma mark - Support classes
+
+// A wrapper around a MTLBuffer object that knows the last time it was reused
+@interface MetalBuffer : NSObject
+@property (nonatomic, strong) id<MTLBuffer> buffer;
+@property (nonatomic, assign) double        lastReuseTime;
+- (instancetype)initWithBuffer:(id<MTLBuffer>)buffer;
+@end
+
+// An object that encapsulates the data necessary to uniquely identify a
+// render pipeline state. These are used as cache keys.
+@interface FramebufferDescriptor : NSObject<NSCopying>
+@property (nonatomic, assign) unsigned long  sampleCount;
+@property (nonatomic, assign) MTLPixelFormat colorPixelFormat;
+@property (nonatomic, assign) MTLPixelFormat depthPixelFormat;
+@property (nonatomic, assign) MTLPixelFormat stencilPixelFormat;
+- (instancetype)initWithRenderPassDescriptor:(MTLRenderPassDescriptor*)renderPassDescriptor;
+@end
+
+// A singleton that stores long-lived objects that are needed by the Metal
+// renderer backend. Stores the render pipeline state cache and the default
+// font texture, and manages the reusable buffer cache.
+@interface MetalContext : NSObject
+@property (nonatomic, strong) id<MTLDevice>                 device;
+@property (nonatomic, strong) id<MTLDepthStencilState>      depthStencilState;
+@property (nonatomic, strong) FramebufferDescriptor*        framebufferDescriptor; // framebuffer descriptor for current frame; transient
+@property (nonatomic, strong) NSMutableDictionary*          renderPipelineStateCache; // pipeline cache; keyed on framebuffer descriptors
+@property (nonatomic, strong, nullable) id<MTLTexture>      fontTexture;
+@property (nonatomic, strong) NSMutableArray<MetalBuffer*>* bufferCache;
+@property (nonatomic, assign) double                        lastBufferCachePurge;
+- (MetalBuffer*)dequeueReusableBufferOfLength:(NSUInteger)length device:(id<MTLDevice>)device;
+- (id<MTLRenderPipelineState>)renderPipelineStateForFramebufferDescriptor:(FramebufferDescriptor*)descriptor device:(id<MTLDevice>)device;
+@end
+
+struct ImGui_ImplMetal_Data
+{
+    MetalContext*               SharedMetalContext;
+
+    ImGui_ImplMetal_Data()      { memset(this, 0, sizeof(*this)); }
+};
+
+static ImGui_ImplMetal_Data*    ImGui_ImplMetal_CreateBackendData() { return IM_NEW(ImGui_ImplMetal_Data)(); }
+static ImGui_ImplMetal_Data*    ImGui_ImplMetal_GetBackendData()    { return ImGui::GetCurrentContext() ? (ImGui_ImplMetal_Data*)ImGui::GetIO().BackendRendererUserData : nullptr; }
+static void                     ImGui_ImplMetal_DestroyBackendData(){ IM_DELETE(ImGui_ImplMetal_GetBackendData()); }
+
+static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
+
+#ifdef IMGUI_IMPL_METAL_CPP
+
+#pragma mark - Dear ImGui Metal C++ Backend API
+
+bool ImGui_ImplMetal_Init(MTL::Device* device)
+{
+    return ImGui_ImplMetal_Init((__bridge id<MTLDevice>)(device));
+}
+
+void ImGui_ImplMetal_NewFrame(MTL::RenderPassDescriptor* renderPassDescriptor)
+{
+    ImGui_ImplMetal_NewFrame((__bridge MTLRenderPassDescriptor*)(renderPassDescriptor));
+}
+
+void ImGui_ImplMetal_RenderDrawData(ImDrawData* draw_data,
+                                    MTL::CommandBuffer* commandBuffer,
+                                    MTL::RenderCommandEncoder* commandEncoder)
+{
+    ImGui_ImplMetal_RenderDrawData(draw_data,
+                                   (__bridge id<MTLCommandBuffer>)(commandBuffer),
+                                   (__bridge id<MTLRenderCommandEncoder>)(commandEncoder));
+
+}
+
+bool ImGui_ImplMetal_CreateFontsTexture(MTL::Device* device)
+{
+    return ImGui_ImplMetal_CreateFontsTexture((__bridge id<MTLDevice>)(device));
+}
+
+bool ImGui_ImplMetal_CreateDeviceObjects(MTL::Device* device)
+{
+    return ImGui_ImplMetal_CreateDeviceObjects((__bridge id<MTLDevice>)(device));
+}
+
+#endif // #ifdef IMGUI_IMPL_METAL_CPP
+
+#pragma mark - Dear ImGui Metal Backend API
+
+bool ImGui_ImplMetal_Init(id<MTLDevice> device)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_CreateBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_metal";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->SharedMetalContext = [[MetalContext alloc] init];
+    bd->SharedMetalContext.device = device;
+
+    return true;
+}
+
+void ImGui_ImplMetal_Shutdown()
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGui_ImplMetal_DestroyDeviceObjects();
+    ImGui_ImplMetal_DestroyBackendData();
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+}
+
+void ImGui_ImplMetal_NewFrame(MTLRenderPassDescriptor* renderPassDescriptor)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    IM_ASSERT(bd->SharedMetalContext != nil && "No Metal context. Did you call ImGui_ImplMetal_Init() ?");
+    bd->SharedMetalContext.framebufferDescriptor = [[FramebufferDescriptor alloc] initWithRenderPassDescriptor:renderPassDescriptor];
+
+    if (bd->SharedMetalContext.depthStencilState == nil)
+        ImGui_ImplMetal_CreateDeviceObjects(bd->SharedMetalContext.device);
+}
+
+static void ImGui_ImplMetal_SetupRenderState(ImDrawData* drawData, id<MTLCommandBuffer> commandBuffer,
+    id<MTLRenderCommandEncoder> commandEncoder, id<MTLRenderPipelineState> renderPipelineState,
+    MetalBuffer* vertexBuffer, size_t vertexBufferOffset)
+{
+    IM_UNUSED(commandBuffer);
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    [commandEncoder setCullMode:MTLCullModeNone];
+    [commandEncoder setDepthStencilState:bd->SharedMetalContext.depthStencilState];
+
+    // Setup viewport, orthographic projection matrix
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to
+    // draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is typically (0,0) for single viewport apps.
+    MTLViewport viewport =
+    {
+        .originX = 0.0,
+        .originY = 0.0,
+        .width = (double)(drawData->DisplaySize.x * drawData->FramebufferScale.x),
+        .height = (double)(drawData->DisplaySize.y * drawData->FramebufferScale.y),
+        .znear = 0.0,
+        .zfar = 1.0
+    };
+    [commandEncoder setViewport:viewport];
+
+    float L = drawData->DisplayPos.x;
+    float R = drawData->DisplayPos.x + drawData->DisplaySize.x;
+    float T = drawData->DisplayPos.y;
+    float B = drawData->DisplayPos.y + drawData->DisplaySize.y;
+    float N = (float)viewport.znear;
+    float F = (float)viewport.zfar;
+    const float ortho_projection[4][4] =
+    {
+        { 2.0f/(R-L),   0.0f,           0.0f,   0.0f },
+        { 0.0f,         2.0f/(T-B),     0.0f,   0.0f },
+        { 0.0f,         0.0f,        1/(F-N),   0.0f },
+        { (R+L)/(L-R),  (T+B)/(B-T), N/(F-N),   1.0f },
+    };
+    [commandEncoder setVertexBytes:&ortho_projection length:sizeof(ortho_projection) atIndex:1];
+
+    [commandEncoder setRenderPipelineState:renderPipelineState];
+
+    [commandEncoder setVertexBuffer:vertexBuffer.buffer offset:0 atIndex:0];
+    [commandEncoder setVertexBufferOffset:vertexBufferOffset atIndex:0];
+}
+
+// Metal Render function.
+void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> commandBuffer, id<MTLRenderCommandEncoder> commandEncoder)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    MetalContext* ctx = bd->SharedMetalContext;
+
+    // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+    int fb_width = (int)(drawData->DisplaySize.x * drawData->FramebufferScale.x);
+    int fb_height = (int)(drawData->DisplaySize.y * drawData->FramebufferScale.y);
+    if (fb_width <= 0 || fb_height <= 0 || drawData->CmdListsCount == 0)
+        return;
+
+    // Try to retrieve a render pipeline state that is compatible with the framebuffer config for this frame
+    // The hit rate for this cache should be very near 100%.
+    id<MTLRenderPipelineState> renderPipelineState = ctx.renderPipelineStateCache[ctx.framebufferDescriptor];
+    if (renderPipelineState == nil)
+    {
+        // No luck; make a new render pipeline state
+        renderPipelineState = [ctx renderPipelineStateForFramebufferDescriptor:ctx.framebufferDescriptor device:commandBuffer.device];
+
+        // Cache render pipeline state for later reuse
+        ctx.renderPipelineStateCache[ctx.framebufferDescriptor] = renderPipelineState;
+    }
+
+    size_t vertexBufferLength = (size_t)drawData->TotalVtxCount * sizeof(ImDrawVert);
+    size_t indexBufferLength = (size_t)drawData->TotalIdxCount * sizeof(ImDrawIdx);
+    MetalBuffer* vertexBuffer = [ctx dequeueReusableBufferOfLength:vertexBufferLength device:commandBuffer.device];
+    MetalBuffer* indexBuffer = [ctx dequeueReusableBufferOfLength:indexBufferLength device:commandBuffer.device];
+
+    ImGui_ImplMetal_SetupRenderState(drawData, commandBuffer, commandEncoder, renderPipelineState, vertexBuffer, 0);
+
+    // Will project scissor/clipping rectangles into framebuffer space
+    ImVec2 clip_off = drawData->DisplayPos;         // (0,0) unless using multi-viewports
+    ImVec2 clip_scale = drawData->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
+
+    // Render command lists
+    size_t vertexBufferOffset = 0;
+    size_t indexBufferOffset = 0;
+    for (int n = 0; n < drawData->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = drawData->CmdLists[n];
+
+        memcpy((char*)vertexBuffer.buffer.contents + vertexBufferOffset, cmd_list->VtxBuffer.Data, (size_t)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy((char*)indexBuffer.buffer.contents + indexBufferOffset, cmd_list->IdxBuffer.Data, (size_t)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplMetal_SetupRenderState(drawData, commandBuffer, commandEncoder, renderPipelineState, vertexBuffer, vertexBufferOffset);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+
+                // Clamp to viewport as setScissorRect() won't accept values that are off bounds
+                if (clip_min.x < 0.0f) { clip_min.x = 0.0f; }
+                if (clip_min.y < 0.0f) { clip_min.y = 0.0f; }
+                if (clip_max.x > fb_width) { clip_max.x = (float)fb_width; }
+                if (clip_max.y > fb_height) { clip_max.y = (float)fb_height; }
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+                if (pcmd->ElemCount == 0) // drawIndexedPrimitives() validation doesn't accept this
+                    continue;
+
+                // Apply scissor/clipping rectangle
+                MTLScissorRect scissorRect =
+                {
+                    .x = NSUInteger(clip_min.x),
+                    .y = NSUInteger(clip_min.y),
+                    .width = NSUInteger(clip_max.x - clip_min.x),
+                    .height = NSUInteger(clip_max.y - clip_min.y)
+                };
+                [commandEncoder setScissorRect:scissorRect];
+
+                // Bind texture, Draw
+                if (ImTextureID tex_id = pcmd->GetTexID())
+                    [commandEncoder setFragmentTexture:(__bridge id<MTLTexture>)(tex_id) atIndex:0];
+
+                [commandEncoder setVertexBufferOffset:(vertexBufferOffset + pcmd->VtxOffset * sizeof(ImDrawVert)) atIndex:0];
+                [commandEncoder drawIndexedPrimitives:MTLPrimitiveTypeTriangle
+                                           indexCount:pcmd->ElemCount
+                                            indexType:sizeof(ImDrawIdx) == 2 ? MTLIndexTypeUInt16 : MTLIndexTypeUInt32
+                                          indexBuffer:indexBuffer.buffer
+                                    indexBufferOffset:indexBufferOffset + pcmd->IdxOffset * sizeof(ImDrawIdx)];
+            }
+        }
+
+        vertexBufferOffset += (size_t)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert);
+        indexBufferOffset += (size_t)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx);
+    }
+
+    [commandBuffer addCompletedHandler:^(id<MTLCommandBuffer>)
+    {
+        dispatch_async(dispatch_get_main_queue(), ^{
+            ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+            if (bd != nullptr)
+            {
+                @synchronized(bd->SharedMetalContext.bufferCache)
+                {
+                    [bd->SharedMetalContext.bufferCache addObject:vertexBuffer];
+                    [bd->SharedMetalContext.bufferCache addObject:indexBuffer];
+                }
+            }
+        });
+    }];
+}
+
+bool ImGui_ImplMetal_CreateFontsTexture(id<MTLDevice> device)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // We are retrieving and uploading the font atlas as a 4-channels RGBA texture here.
+    // In theory we could call GetTexDataAsAlpha8() and upload a 1-channel texture to save on memory access bandwidth.
+    // However, using a shader designed for 1-channel texture would make it less obvious to use the ImTextureID facility to render users own textures.
+    // You can make that change in your implementation.
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
+    MTLTextureDescriptor* textureDescriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatRGBA8Unorm
+                                                                                                 width:(NSUInteger)width
+                                                                                                height:(NSUInteger)height
+                                                                                             mipmapped:NO];
+    textureDescriptor.usage = MTLTextureUsageShaderRead;
+#if TARGET_OS_OSX || TARGET_OS_MACCATALYST
+    textureDescriptor.storageMode = MTLStorageModeManaged;
+#else
+    textureDescriptor.storageMode = MTLStorageModeShared;
+#endif
+    id <MTLTexture> texture = [device newTextureWithDescriptor:textureDescriptor];
+    [texture replaceRegion:MTLRegionMake2D(0, 0, (NSUInteger)width, (NSUInteger)height) mipmapLevel:0 withBytes:pixels bytesPerRow:(NSUInteger)width * 4];
+    bd->SharedMetalContext.fontTexture = texture;
+    io.Fonts->SetTexID((__bridge void*)bd->SharedMetalContext.fontTexture); // ImTextureID == void*
+
+    return (bd->SharedMetalContext.fontTexture != nil);
+}
+
+void ImGui_ImplMetal_DestroyFontsTexture()
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    bd->SharedMetalContext.fontTexture = nil;
+    io.Fonts->SetTexID(0);
+}
+
+bool ImGui_ImplMetal_CreateDeviceObjects(id<MTLDevice> device)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    MTLDepthStencilDescriptor* depthStencilDescriptor = [[MTLDepthStencilDescriptor alloc] init];
+    depthStencilDescriptor.depthWriteEnabled = NO;
+    depthStencilDescriptor.depthCompareFunction = MTLCompareFunctionAlways;
+    bd->SharedMetalContext.depthStencilState = [device newDepthStencilStateWithDescriptor:depthStencilDescriptor];
+    ImGui_ImplMetal_CreateFontsTexture(device);
+
+    return true;
+}
+
+void ImGui_ImplMetal_DestroyDeviceObjects()
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    ImGui_ImplMetal_DestroyFontsTexture();
+    [bd->SharedMetalContext.renderPipelineStateCache removeAllObjects];
+}
+
+#pragma mark - MetalBuffer implementation
+
+@implementation MetalBuffer
+- (instancetype)initWithBuffer:(id<MTLBuffer>)buffer
+{
+    if ((self = [super init]))
+    {
+        _buffer = buffer;
+        _lastReuseTime = GetMachAbsoluteTimeInSeconds();
+    }
+    return self;
+}
+@end
+
+#pragma mark - FramebufferDescriptor implementation
+
+@implementation FramebufferDescriptor
+- (instancetype)initWithRenderPassDescriptor:(MTLRenderPassDescriptor*)renderPassDescriptor
+{
+    if ((self = [super init]))
+    {
+        _sampleCount = renderPassDescriptor.colorAttachments[0].texture.sampleCount;
+        _colorPixelFormat = renderPassDescriptor.colorAttachments[0].texture.pixelFormat;
+        _depthPixelFormat = renderPassDescriptor.depthAttachment.texture.pixelFormat;
+        _stencilPixelFormat = renderPassDescriptor.stencilAttachment.texture.pixelFormat;
+    }
+    return self;
+}
+
+- (nonnull id)copyWithZone:(nullable NSZone*)zone
+{
+    FramebufferDescriptor* copy = [[FramebufferDescriptor allocWithZone:zone] init];
+    copy.sampleCount = self.sampleCount;
+    copy.colorPixelFormat = self.colorPixelFormat;
+    copy.depthPixelFormat = self.depthPixelFormat;
+    copy.stencilPixelFormat = self.stencilPixelFormat;
+    return copy;
+}
+
+- (NSUInteger)hash
+{
+    NSUInteger sc = _sampleCount & 0x3;
+    NSUInteger cf = _colorPixelFormat & 0x3FF;
+    NSUInteger df = _depthPixelFormat & 0x3FF;
+    NSUInteger sf = _stencilPixelFormat & 0x3FF;
+    NSUInteger hash = (sf << 22) | (df << 12) | (cf << 2) | sc;
+    return hash;
+}
+
+- (BOOL)isEqual:(id)object
+{
+    FramebufferDescriptor* other = object;
+    if (![other isKindOfClass:[FramebufferDescriptor class]])
+        return NO;
+    return other.sampleCount == self.sampleCount      &&
+    other.colorPixelFormat   == self.colorPixelFormat &&
+    other.depthPixelFormat   == self.depthPixelFormat &&
+    other.stencilPixelFormat == self.stencilPixelFormat;
+}
+
+@end
+
+#pragma mark - MetalContext implementation
+
+@implementation MetalContext
+- (instancetype)init
+{
+    if ((self = [super init]))
+    {
+        self.renderPipelineStateCache = [NSMutableDictionary dictionary];
+        self.bufferCache = [NSMutableArray array];
+        _lastBufferCachePurge = GetMachAbsoluteTimeInSeconds();
+    }
+    return self;
+}
+
+- (MetalBuffer*)dequeueReusableBufferOfLength:(NSUInteger)length device:(id<MTLDevice>)device
+{
+    uint64_t now = GetMachAbsoluteTimeInSeconds();
+
+    @synchronized(self.bufferCache)
+    {
+        // Purge old buffers that haven't been useful for a while
+        if (now - self.lastBufferCachePurge > 1.0)
+        {
+            NSMutableArray* survivors = [NSMutableArray array];
+            for (MetalBuffer* candidate in self.bufferCache)
+                if (candidate.lastReuseTime > self.lastBufferCachePurge)
+                    [survivors addObject:candidate];
+            self.bufferCache = [survivors mutableCopy];
+            self.lastBufferCachePurge = now;
+        }
+
+        // See if we have a buffer we can reuse
+        MetalBuffer* bestCandidate = nil;
+        for (MetalBuffer* candidate in self.bufferCache)
+            if (candidate.buffer.length >= length && (bestCandidate == nil || bestCandidate.lastReuseTime > candidate.lastReuseTime))
+                bestCandidate = candidate;
+
+        if (bestCandidate != nil)
+        {
+            [self.bufferCache removeObject:bestCandidate];
+            bestCandidate.lastReuseTime = now;
+            return bestCandidate;
+        }
+    }
+
+    // No luck; make a new buffer
+    id<MTLBuffer> backing = [device newBufferWithLength:length options:MTLResourceStorageModeShared];
+    return [[MetalBuffer alloc] initWithBuffer:backing];
+}
+
+// Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling.
+- (id<MTLRenderPipelineState>)renderPipelineStateForFramebufferDescriptor:(FramebufferDescriptor*)descriptor device:(id<MTLDevice>)device
+{
+    NSError* error = nil;
+
+    NSString* shaderSource = @""
+    "#include <metal_stdlib>\n"
+    "using namespace metal;\n"
+    "\n"
+    "struct Uniforms {\n"
+    "    float4x4 projectionMatrix;\n"
+    "};\n"
+    "\n"
+    "struct VertexIn {\n"
+    "    float2 position  [[attribute(0)]];\n"
+    "    float2 texCoords [[attribute(1)]];\n"
+    "    uchar4 color     [[attribute(2)]];\n"
+    "};\n"
+    "\n"
+    "struct VertexOut {\n"
+    "    float4 position [[position]];\n"
+    "    float2 texCoords;\n"
+    "    float4 color;\n"
+    "};\n"
+    "\n"
+    "vertex VertexOut vertex_main(VertexIn in                 [[stage_in]],\n"
+    "                             constant Uniforms &uniforms [[buffer(1)]]) {\n"
+    "    VertexOut out;\n"
+    "    out.position = uniforms.projectionMatrix * float4(in.position, 0, 1);\n"
+    "    out.texCoords = in.texCoords;\n"
+    "    out.color = float4(in.color) / float4(255.0);\n"
+    "    return out;\n"
+    "}\n"
+    "\n"
+    "fragment half4 fragment_main(VertexOut in [[stage_in]],\n"
+    "                             texture2d<half, access::sample> texture [[texture(0)]]) {\n"
+    "    constexpr sampler linearSampler(coord::normalized, min_filter::linear, mag_filter::linear, mip_filter::linear);\n"
+    "    half4 texColor = texture.sample(linearSampler, in.texCoords);\n"
+    "    return half4(in.color) * texColor;\n"
+    "}\n";
+
+    id<MTLLibrary> library = [device newLibraryWithSource:shaderSource options:nil error:&error];
+    if (library == nil)
+    {
+        NSLog(@"Error: failed to create Metal library: %@", error);
+        return nil;
+    }
+
+    id<MTLFunction> vertexFunction = [library newFunctionWithName:@"vertex_main"];
+    id<MTLFunction> fragmentFunction = [library newFunctionWithName:@"fragment_main"];
+
+    if (vertexFunction == nil || fragmentFunction == nil)
+    {
+        NSLog(@"Error: failed to find Metal shader functions in library: %@", error);
+        return nil;
+    }
+
+    MTLVertexDescriptor* vertexDescriptor = [MTLVertexDescriptor vertexDescriptor];
+    vertexDescriptor.attributes[0].offset = IM_OFFSETOF(ImDrawVert, pos);
+    vertexDescriptor.attributes[0].format = MTLVertexFormatFloat2; // position
+    vertexDescriptor.attributes[0].bufferIndex = 0;
+    vertexDescriptor.attributes[1].offset = IM_OFFSETOF(ImDrawVert, uv);
+    vertexDescriptor.attributes[1].format = MTLVertexFormatFloat2; // texCoords
+    vertexDescriptor.attributes[1].bufferIndex = 0;
+    vertexDescriptor.attributes[2].offset = IM_OFFSETOF(ImDrawVert, col);
+    vertexDescriptor.attributes[2].format = MTLVertexFormatUChar4; // color
+    vertexDescriptor.attributes[2].bufferIndex = 0;
+    vertexDescriptor.layouts[0].stepRate = 1;
+    vertexDescriptor.layouts[0].stepFunction = MTLVertexStepFunctionPerVertex;
+    vertexDescriptor.layouts[0].stride = sizeof(ImDrawVert);
+
+    MTLRenderPipelineDescriptor* pipelineDescriptor = [[MTLRenderPipelineDescriptor alloc] init];
+    pipelineDescriptor.vertexFunction = vertexFunction;
+    pipelineDescriptor.fragmentFunction = fragmentFunction;
+    pipelineDescriptor.vertexDescriptor = vertexDescriptor;
+    pipelineDescriptor.rasterSampleCount = self.framebufferDescriptor.sampleCount;
+    pipelineDescriptor.colorAttachments[0].pixelFormat = self.framebufferDescriptor.colorPixelFormat;
+    pipelineDescriptor.colorAttachments[0].blendingEnabled = YES;
+    pipelineDescriptor.colorAttachments[0].rgbBlendOperation = MTLBlendOperationAdd;
+    pipelineDescriptor.colorAttachments[0].sourceRGBBlendFactor = MTLBlendFactorSourceAlpha;
+    pipelineDescriptor.colorAttachments[0].destinationRGBBlendFactor = MTLBlendFactorOneMinusSourceAlpha;
+    pipelineDescriptor.colorAttachments[0].alphaBlendOperation = MTLBlendOperationAdd;
+    pipelineDescriptor.colorAttachments[0].sourceAlphaBlendFactor = MTLBlendFactorOne;
+    pipelineDescriptor.colorAttachments[0].destinationAlphaBlendFactor = MTLBlendFactorOneMinusSourceAlpha;
+    pipelineDescriptor.depthAttachmentPixelFormat = self.framebufferDescriptor.depthPixelFormat;
+    pipelineDescriptor.stencilAttachmentPixelFormat = self.framebufferDescriptor.stencilPixelFormat;
+
+    id<MTLRenderPipelineState> renderPipelineState = [device newRenderPipelineStateWithDescriptor:pipelineDescriptor error:&error];
+    if (error != nil)
+        NSLog(@"Error: failed to create Metal pipeline state: %@", error);
+
+    return renderPipelineState;
+}
+
+@end
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_opengl2.cpp

@@ -0,0 +1,302 @@
+// dear imgui: Renderer Backend for OpenGL2 (legacy OpenGL, fixed pipeline)
+// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// **DO NOT USE THIS CODE IF YOUR CODE/ENGINE IS USING MODERN OPENGL (SHADERS, VBO, VAO, etc.)**
+// **Prefer using the code in imgui_impl_opengl3.cpp**
+// This code is mostly provided as a reference to learn how ImGui integration works, because it is shorter to read.
+// If your code is using GL3+ context or any semi modern OpenGL calls, using this is likely to make everything more
+// complicated, will require your code to reset every single OpenGL attributes to their initial state, and might
+// confuse your GPU driver.
+// The GL2 code is unable to reset attributes or even call e.g. "glUseProgram(0)" because they don't exist in that API.
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-12-08: OpenGL: Fixed mishandling of the the ImDrawCmd::IdxOffset field! This is an old bug but it never had an effect until some internal rendering changes in 1.86.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-01-03: OpenGL: Backup, setup and restore GL_SHADE_MODEL state, disable GL_STENCIL_TEST and disable GL_NORMAL_ARRAY client state to increase compatibility with legacy OpenGL applications.
+//  2020-01-23: OpenGL: Backup, setup and restore GL_TEXTURE_ENV to increase compatibility with legacy OpenGL applications.
+//  2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-08-03: OpenGL: Disabling/restoring GL_LIGHTING and GL_COLOR_MATERIAL to increase compatibility with legacy OpenGL applications.
+//  2018-06-08: Misc: Extracted imgui_impl_opengl2.cpp/.h away from the old combined GLFW/SDL+OpenGL2 examples.
+//  2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplOpenGL2_RenderDrawData() in the .h file so you can call it yourself.
+//  2017-09-01: OpenGL: Save and restore current polygon mode.
+//  2016-09-10: OpenGL: Uploading font texture as RGBA32 to increase compatibility with users shaders (not ideal).
+//  2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_opengl2.h"
+#include <stdint.h>     // intptr_t
+
+// Clang/GCC warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-macros"                      // warning: macro is not used
+#pragma clang diagnostic ignored "-Wnonportable-system-include-path"
+#endif
+
+// Include OpenGL header (without an OpenGL loader) requires a bit of fiddling
+#if defined(_WIN32) && !defined(APIENTRY)
+#define APIENTRY __stdcall                  // It is customary to use APIENTRY for OpenGL function pointer declarations on all platforms.  Additionally, the Windows OpenGL header needs APIENTRY.
+#endif
+#if defined(_WIN32) && !defined(WINGDIAPI)
+#define WINGDIAPI __declspec(dllimport)     // Some Windows OpenGL headers need this
+#endif
+#if defined(__APPLE__)
+#define GL_SILENCE_DEPRECATION
+#include <OpenGL/gl.h>
+#else
+#include <GL/gl.h>
+#endif
+
+struct ImGui_ImplOpenGL2_Data
+{
+    GLuint       FontTexture;
+
+    ImGui_ImplOpenGL2_Data() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplOpenGL2_Data* ImGui_ImplOpenGL2_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL2_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+bool    ImGui_ImplOpenGL2_Init()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplOpenGL2_Data* bd = IM_NEW(ImGui_ImplOpenGL2_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_opengl2";
+
+    return true;
+}
+
+void    ImGui_ImplOpenGL2_Shutdown()
+{
+    ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplOpenGL2_DestroyDeviceObjects();
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    IM_DELETE(bd);
+}
+
+void    ImGui_ImplOpenGL2_NewFrame()
+{
+    ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplOpenGL2_Init()?");
+
+    if (!bd->FontTexture)
+        ImGui_ImplOpenGL2_CreateDeviceObjects();
+}
+
+static void ImGui_ImplOpenGL2_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height)
+{
+    // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers, polygon fill.
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    //glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA); // In order to composite our output buffer we need to preserve alpha
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_STENCIL_TEST);
+    glDisable(GL_LIGHTING);
+    glDisable(GL_COLOR_MATERIAL);
+    glEnable(GL_SCISSOR_TEST);
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+    glEnableClientState(GL_COLOR_ARRAY);
+    glDisableClientState(GL_NORMAL_ARRAY);
+    glEnable(GL_TEXTURE_2D);
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+    glShadeModel(GL_SMOOTH);
+    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+
+    // If you are using this code with non-legacy OpenGL header/contexts (which you should not, prefer using imgui_impl_opengl3.cpp!!),
+    // you may need to backup/reset/restore other state, e.g. for current shader using the commented lines below.
+    // (DO NOT MODIFY THIS FILE! Add the code in your calling function)
+    //   GLint last_program;
+    //   glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
+    //   glUseProgram(0);
+    //   ImGui_ImplOpenGL2_RenderDrawData(...);
+    //   glUseProgram(last_program)
+    // There are potentially many more states you could need to clear/setup that we can't access from default headers.
+    // e.g. glBindBuffer(GL_ARRAY_BUFFER, 0), glDisable(GL_TEXTURE_CUBE_MAP).
+
+    // Setup viewport, orthographic projection matrix
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
+    glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height);
+    glMatrixMode(GL_PROJECTION);
+    glPushMatrix();
+    glLoadIdentity();
+    glOrtho(draw_data->DisplayPos.x, draw_data->DisplayPos.x + draw_data->DisplaySize.x, draw_data->DisplayPos.y + draw_data->DisplaySize.y, draw_data->DisplayPos.y, -1.0f, +1.0f);
+    glMatrixMode(GL_MODELVIEW);
+    glPushMatrix();
+    glLoadIdentity();
+}
+
+// OpenGL2 Render function.
+// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly.
+// This is in order to be able to run within an OpenGL engine that doesn't do so.
+void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+    int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x);
+    int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y);
+    if (fb_width == 0 || fb_height == 0)
+        return;
+
+    // Backup GL state
+    GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
+    GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
+    GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
+    GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
+    GLint last_shade_model; glGetIntegerv(GL_SHADE_MODEL, &last_shade_model);
+    GLint last_tex_env_mode; glGetTexEnviv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, &last_tex_env_mode);
+    glPushAttrib(GL_ENABLE_BIT | GL_COLOR_BUFFER_BIT | GL_TRANSFORM_BIT);
+
+    // Setup desired GL state
+    ImGui_ImplOpenGL2_SetupRenderState(draw_data, fb_width, fb_height);
+
+    // Will project scissor/clipping rectangles into framebuffer space
+    ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
+    ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
+
+    // Render command lists
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+        glVertexPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + IM_OFFSETOF(ImDrawVert, pos)));
+        glTexCoordPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + IM_OFFSETOF(ImDrawVert, uv)));
+        glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + IM_OFFSETOF(ImDrawVert, col)));
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplOpenGL2_SetupRenderState(draw_data, fb_width, fb_height);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle (Y is inverted in OpenGL)
+                glScissor((int)clip_min.x, (int)((float)fb_height - clip_max.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y));
+
+                // Bind texture, Draw
+                glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->GetTexID());
+                glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer + pcmd->IdxOffset);
+            }
+        }
+    }
+
+    // Restore modified GL state
+    glDisableClientState(GL_COLOR_ARRAY);
+    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    glDisableClientState(GL_VERTEX_ARRAY);
+    glBindTexture(GL_TEXTURE_2D, (GLuint)last_texture);
+    glMatrixMode(GL_MODELVIEW);
+    glPopMatrix();
+    glMatrixMode(GL_PROJECTION);
+    glPopMatrix();
+    glPopAttrib();
+    glPolygonMode(GL_FRONT, (GLenum)last_polygon_mode[0]); glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1]);
+    glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
+    glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]);
+    glShadeModel(last_shade_model);
+    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, last_tex_env_mode);
+}
+
+bool ImGui_ImplOpenGL2_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
+
+    // Upload texture to graphics system
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    GLint last_texture;
+    glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
+    glGenTextures(1, &bd->FontTexture);
+    glBindTexture(GL_TEXTURE_2D, bd->FontTexture);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
+
+    // Restore state
+    glBindTexture(GL_TEXTURE_2D, last_texture);
+
+    return true;
+}
+
+void ImGui_ImplOpenGL2_DestroyFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
+    if (bd->FontTexture)
+    {
+        glDeleteTextures(1, &bd->FontTexture);
+        io.Fonts->SetTexID(0);
+        bd->FontTexture = 0;
+    }
+}
+
+bool    ImGui_ImplOpenGL2_CreateDeviceObjects()
+{
+    return ImGui_ImplOpenGL2_CreateFontsTexture();
+}
+
+void    ImGui_ImplOpenGL2_DestroyDeviceObjects()
+{
+    ImGui_ImplOpenGL2_DestroyFontsTexture();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_opengl2.h

@@ -0,0 +1,38 @@
+// dear imgui: Renderer Backend for OpenGL2 (legacy OpenGL, fixed pipeline)
+// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// **DO NOT USE THIS CODE IF YOUR CODE/ENGINE IS USING MODERN OPENGL (SHADERS, VBO, VAO, etc.)**
+// **Prefer using the code in imgui_impl_opengl3.cpp**
+// This code is mostly provided as a reference to learn how ImGui integration works, because it is shorter to read.
+// If your code is using GL3+ context or any semi modern OpenGL calls, using this is likely to make everything more
+// complicated, will require your code to reset every single OpenGL attributes to their initial state, and might
+// confuse your GPU driver.
+// The GL2 code is unable to reset attributes or even call e.g. "glUseProgram(0)" because they don't exist in that API.
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL2_Init();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL2_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL2_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL2_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL2_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL2_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL2_DestroyDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_opengl3.cpp

@@ -0,0 +1,945 @@
+// dear imgui: Renderer Backend for modern OpenGL with shaders / programmatic pipeline
+// - Desktop GL: 2.x 3.x 4.x
+// - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0)
+// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
+
+// About WebGL/ES:
+// - You need to '#define IMGUI_IMPL_OPENGL_ES2' or '#define IMGUI_IMPL_OPENGL_ES3' to use WebGL or OpenGL ES.
+// - This is done automatically on iOS, Android and Emscripten targets.
+// - For other targets, the define needs to be visible from the imgui_impl_opengl3.cpp compilation unit. If unsure, define globally or in imconfig.h.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-06-20: OpenGL: Fixed erroneous use glGetIntegerv(GL_CONTEXT_PROFILE_MASK) on contexts lower than 3.2. (#6539, #6333)
+//  2023-05-09: OpenGL: Support for glBindSampler() backup/restore on ES3. (#6375)
+//  2023-04-18: OpenGL: Restore front and back polygon mode separately when supported by context. (#6333)
+//  2023-03-23: OpenGL: Properly restoring "no shader program bound" if it was the case prior to running the rendering function. (#6267, #6220, #6224)
+//  2023-03-15: OpenGL: Fixed GL loader crash when GL_VERSION returns NULL. (#6154, #4445, #3530)
+//  2023-03-06: OpenGL: Fixed restoration of a potentially deleted OpenGL program, by calling glIsProgram(). (#6220, #6224)
+//  2022-11-09: OpenGL: Reverted use of glBufferSubData(), too many corruptions issues + old issues seemingly can't be reproed with Intel drivers nowadays (revert 2021-12-15 and 2022-05-23 changes).
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-27: OpenGL: Added ability to '#define IMGUI_IMPL_OPENGL_DEBUG'.
+//  2022-05-23: OpenGL: Reworking 2021-12-15 "Using buffer orphaning" so it only happens on Intel GPU, seems to cause problems otherwise. (#4468, #4825, #4832, #5127).
+//  2022-05-13: OpenGL: Fixed state corruption on OpenGL ES 2.0 due to not preserving GL_ELEMENT_ARRAY_BUFFER_BINDING and vertex attribute states.
+//  2021-12-15: OpenGL: Using buffer orphaning + glBufferSubData(), seems to fix leaks with multi-viewports with some Intel HD drivers.
+//  2021-08-23: OpenGL: Fixed ES 3.0 shader ("#version 300 es") use normal precision floats to avoid wobbly rendering at HD resolutions.
+//  2021-08-19: OpenGL: Embed and use our own minimal GL loader (imgui_impl_opengl3_loader.h), removing requirement and support for third-party loader.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-06-25: OpenGL: Use OES_vertex_array extension on Emscripten + backup/restore current state.
+//  2021-06-21: OpenGL: Destroy individual vertex/fragment shader objects right after they are linked into the main shader.
+//  2021-05-24: OpenGL: Access GL_CLIP_ORIGIN when "GL_ARB_clip_control" extension is detected, inside of just OpenGL 4.5 version.
+//  2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-04-06: OpenGL: Don't try to read GL_CLIP_ORIGIN unless we're OpenGL 4.5 or greater.
+//  2021-02-18: OpenGL: Change blending equation to preserve alpha in output buffer.
+//  2021-01-03: OpenGL: Backup, setup and restore GL_STENCIL_TEST state.
+//  2020-10-23: OpenGL: Backup, setup and restore GL_PRIMITIVE_RESTART state.
+//  2020-10-15: OpenGL: Use glGetString(GL_VERSION) instead of glGetIntegerv(GL_MAJOR_VERSION, ...) when the later returns zero (e.g. Desktop GL 2.x)
+//  2020-09-17: OpenGL: Fix to avoid compiling/calling glBindSampler() on ES or pre 3.3 context which have the defines set by a loader.
+//  2020-07-10: OpenGL: Added support for glad2 OpenGL loader.
+//  2020-05-08: OpenGL: Made default GLSL version 150 (instead of 130) on OSX.
+//  2020-04-21: OpenGL: Fixed handling of glClipControl(GL_UPPER_LEFT) by inverting projection matrix.
+//  2020-04-12: OpenGL: Fixed context version check mistakenly testing for 4.0+ instead of 3.2+ to enable ImGuiBackendFlags_RendererHasVtxOffset.
+//  2020-03-24: OpenGL: Added support for glbinding 2.x OpenGL loader.
+//  2020-01-07: OpenGL: Added support for glbinding 3.x OpenGL loader.
+//  2019-10-25: OpenGL: Using a combination of GL define and runtime GL version to decide whether to use glDrawElementsBaseVertex(). Fix building with pre-3.2 GL loaders.
+//  2019-09-22: OpenGL: Detect default GL loader using __has_include compiler facility.
+//  2019-09-16: OpenGL: Tweak initialization code to allow application calling ImGui_ImplOpenGL3_CreateFontsTexture() before the first NewFrame() call.
+//  2019-05-29: OpenGL: Desktop GL only: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
+//  2019-03-29: OpenGL: Not calling glBindBuffer more than necessary in the render loop.
+//  2019-03-15: OpenGL: Added a GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early.
+//  2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0).
+//  2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader.
+//  2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
+//  2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450).
+//  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
+//  2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT) / GL_CLIP_ORIGIN.
+//  2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used.
+//  2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES".
+//  2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation.
+//  2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link.
+//  2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples.
+//  2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
+//  2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state.
+//  2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a nullptr pointer.
+//  2018-03-06: OpenGL: Added const char* glsl_version parameter to ImGui_ImplOpenGL3_Init() so user can override the GLSL version e.g. "#version 150".
+//  2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context.
+//  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself.
+//  2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150.
+//  2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode.
+//  2017-05-01: OpenGL: Fixed save and restore of current blend func state.
+//  2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE.
+//  2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle.
+//  2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752)
+
+//----------------------------------------
+// OpenGL    GLSL      GLSL
+// version   version   string
+//----------------------------------------
+//  2.0       110       "#version 110"
+//  2.1       120       "#version 120"
+//  3.0       130       "#version 130"
+//  3.1       140       "#version 140"
+//  3.2       150       "#version 150"
+//  3.3       330       "#version 330 core"
+//  4.0       400       "#version 400 core"
+//  4.1       410       "#version 410 core"
+//  4.2       420       "#version 410 core"
+//  4.3       430       "#version 430 core"
+//  ES 2.0    100       "#version 100"      = WebGL 1.0
+//  ES 3.0    300       "#version 300 es"   = WebGL 2.0
+//----------------------------------------
+
+#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
+#define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_opengl3.h"
+#include <stdio.h>
+#include <stdint.h>     // intptr_t
+#if defined(__APPLE__)
+#include <TargetConditionals.h>
+#endif
+
+// Clang/GCC warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wold-style-cast"         // warning: use of old-style cast
+#pragma clang diagnostic ignored "-Wsign-conversion"        // warning: implicit conversion changes signedness
+#pragma clang diagnostic ignored "-Wunused-macros"          // warning: macro is not used
+#pragma clang diagnostic ignored "-Wnonportable-system-include-path"
+#pragma clang diagnostic ignored "-Wcast-function-type"     // warning: cast between incompatible function types (for loader)
+#endif
+#if defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpragmas"                  // warning: unknown option after '#pragma GCC diagnostic' kind
+#pragma GCC diagnostic ignored "-Wunknown-warning-option"   // warning: unknown warning group 'xxx'
+#pragma GCC diagnostic ignored "-Wcast-function-type"       // warning: cast between incompatible function types (for loader)
+#endif
+
+// GL includes
+#if defined(IMGUI_IMPL_OPENGL_ES2)
+#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV))
+#include <OpenGLES/ES2/gl.h>    // Use GL ES 2
+#else
+#include <GLES2/gl2.h>          // Use GL ES 2
+#endif
+#if defined(__EMSCRIPTEN__)
+#ifndef GL_GLEXT_PROTOTYPES
+#define GL_GLEXT_PROTOTYPES
+#endif
+#include <GLES2/gl2ext.h>
+#endif
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
+#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV))
+#include <OpenGLES/ES3/gl.h>    // Use GL ES 3
+#else
+#include <GLES3/gl3.h>          // Use GL ES 3
+#endif
+#elif !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM)
+// Modern desktop OpenGL doesn't have a standard portable header file to load OpenGL function pointers.
+// Helper libraries are often used for this purpose! Here we are using our own minimal custom loader based on gl3w.
+// In the rest of your app/engine, you can use another loader of your choice (gl3w, glew, glad, glbinding, glext, glLoadGen, etc.).
+// If you happen to be developing a new feature for this backend (imgui_impl_opengl3.cpp):
+// - You may need to regenerate imgui_impl_opengl3_loader.h to add new symbols. See https://github.com/dearimgui/gl3w_stripped
+// - You can temporarily use an unstripped version. See https://github.com/dearimgui/gl3w_stripped/releases
+// Changes to this backend using new APIs should be accompanied by a regenerated stripped loader version.
+#define IMGL3W_IMPL
+#include "imgui_impl_opengl3_loader.h"
+#endif
+
+// Vertex arrays are not supported on ES2/WebGL1 unless Emscripten which uses an extension
+#ifndef IMGUI_IMPL_OPENGL_ES2
+#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+#elif defined(__EMSCRIPTEN__)
+#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+#define glBindVertexArray       glBindVertexArrayOES
+#define glGenVertexArrays       glGenVertexArraysOES
+#define glDeleteVertexArrays    glDeleteVertexArraysOES
+#define GL_VERTEX_ARRAY_BINDING GL_VERTEX_ARRAY_BINDING_OES
+#endif
+
+// Desktop GL 2.0+ has glPolygonMode() which GL ES and WebGL don't have.
+#ifdef GL_POLYGON_MODE
+#define IMGUI_IMPL_HAS_POLYGON_MODE
+#endif
+
+// Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have.
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_2)
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
+#endif
+
+// Desktop GL 3.3+ and GL ES 3.0+ have glBindSampler()
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && (defined(IMGUI_IMPL_OPENGL_ES3) || defined(GL_VERSION_3_3))
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
+#endif
+
+// Desktop GL 3.1+ has GL_PRIMITIVE_RESTART state
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_1)
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
+#endif
+
+// Desktop GL use extension detection
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3)
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS
+#endif
+
+// [Debugging]
+//#define IMGUI_IMPL_OPENGL_DEBUG
+#ifdef IMGUI_IMPL_OPENGL_DEBUG
+#include <stdio.h>
+#define GL_CALL(_CALL)      do { _CALL; GLenum gl_err = glGetError(); if (gl_err != 0) fprintf(stderr, "GL error 0x%x returned from '%s'.\n", gl_err, #_CALL); } while (0)  // Call with error check
+#else
+#define GL_CALL(_CALL)      _CALL   // Call without error check
+#endif
+
+// OpenGL Data
+struct ImGui_ImplOpenGL3_Data
+{
+    GLuint          GlVersion;               // Extracted at runtime using GL_MAJOR_VERSION, GL_MINOR_VERSION queries (e.g. 320 for GL 3.2)
+    char            GlslVersionString[32];   // Specified by user or detected based on compile time GL settings.
+    bool            GlProfileIsES2;
+    bool            GlProfileIsES3;
+    bool            GlProfileIsCompat;
+    GLint           GlProfileMask;
+    GLuint          FontTexture;
+    GLuint          ShaderHandle;
+    GLint           AttribLocationTex;       // Uniforms location
+    GLint           AttribLocationProjMtx;
+    GLuint          AttribLocationVtxPos;    // Vertex attributes location
+    GLuint          AttribLocationVtxUV;
+    GLuint          AttribLocationVtxColor;
+    unsigned int    VboHandle, ElementsHandle;
+    GLsizeiptr      VertexBufferSize;
+    GLsizeiptr      IndexBufferSize;
+    bool            HasClipOrigin;
+    bool            UseBufferSubData;
+
+    ImGui_ImplOpenGL3_Data() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplOpenGL3_Data* ImGui_ImplOpenGL3_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// OpenGL vertex attribute state (for ES 1.0 and ES 2.0 only)
+#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+struct ImGui_ImplOpenGL3_VtxAttribState
+{
+    GLint   Enabled, Size, Type, Normalized, Stride;
+    GLvoid* Ptr;
+
+    void GetState(GLint index)
+    {
+        glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &Enabled);
+        glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_SIZE, &Size);
+        glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_TYPE, &Type);
+        glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_NORMALIZED, &Normalized);
+        glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_STRIDE, &Stride);
+        glGetVertexAttribPointerv(index, GL_VERTEX_ATTRIB_ARRAY_POINTER, &Ptr);
+    }
+    void SetState(GLint index)
+    {
+        glVertexAttribPointer(index, Size, Type, (GLboolean)Normalized, Stride, Ptr);
+        if (Enabled) glEnableVertexAttribArray(index); else glDisableVertexAttribArray(index);
+    }
+};
+#endif
+
+// Functions
+bool    ImGui_ImplOpenGL3_Init(const char* glsl_version)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Initialize our loader
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM)
+    if (imgl3wInit() != 0)
+    {
+        fprintf(stderr, "Failed to initialize OpenGL loader!\n");
+        return false;
+    }
+#endif
+
+    // Setup backend capabilities flags
+    ImGui_ImplOpenGL3_Data* bd = IM_NEW(ImGui_ImplOpenGL3_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_opengl3";
+
+    // Query for GL version (e.g. 320 for GL 3.2)
+#if defined(IMGUI_IMPL_OPENGL_ES2)
+    // GLES 2
+    bd->GlVersion = 200;
+    bd->GlProfileIsES2 = true;
+#else
+    // Desktop or GLES 3
+    GLint major = 0;
+    GLint minor = 0;
+    glGetIntegerv(GL_MAJOR_VERSION, &major);
+    glGetIntegerv(GL_MINOR_VERSION, &minor);
+    if (major == 0 && minor == 0)
+    {
+        // Query GL_VERSION in desktop GL 2.x, the string will start with "<major>.<minor>"
+        const char* gl_version = (const char*)glGetString(GL_VERSION);
+        sscanf(gl_version, "%d.%d", &major, &minor);
+    }
+    bd->GlVersion = (GLuint)(major * 100 + minor * 10);
+#if defined(GL_CONTEXT_PROFILE_MASK)
+    if (bd->GlVersion >= 320)
+        glGetIntegerv(GL_CONTEXT_PROFILE_MASK, &bd->GlProfileMask);
+    bd->GlProfileIsCompat = (bd->GlProfileMask & GL_CONTEXT_COMPATIBILITY_PROFILE_BIT) != 0;
+#endif
+
+#if defined(IMGUI_IMPL_OPENGL_ES3)
+    bd->GlProfileIsES3 = true;
+#endif
+
+    bd->UseBufferSubData = false;
+    /*
+    // Query vendor to enable glBufferSubData kludge
+#ifdef _WIN32
+    if (const char* vendor = (const char*)glGetString(GL_VENDOR))
+        if (strncmp(vendor, "Intel", 5) == 0)
+            bd->UseBufferSubData = true;
+#endif
+    */
+#endif
+
+#ifdef IMGUI_IMPL_OPENGL_DEBUG
+    printf("GlVersion = %d\nGlProfileIsCompat = %d\nGlProfileMask = 0x%X\nGlProfileIsES2 = %d, GlProfileIsES3 = %d\nGL_VENDOR = '%s'\nGL_RENDERER = '%s'\n", bd->GlVersion, bd->GlProfileIsCompat, bd->GlProfileMask, bd->GlProfileIsES2, bd->GlProfileIsES3, (const char*)glGetString(GL_VENDOR), (const char*)glGetString(GL_RENDERER)); // [DEBUG]
+#endif
+
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
+    if (bd->GlVersion >= 320)
+        io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+#endif
+
+    // Store GLSL version string so we can refer to it later in case we recreate shaders.
+    // Note: GLSL version is NOT the same as GL version. Leave this to nullptr if unsure.
+    if (glsl_version == nullptr)
+    {
+#if defined(IMGUI_IMPL_OPENGL_ES2)
+        glsl_version = "#version 100";
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
+        glsl_version = "#version 300 es";
+#elif defined(__APPLE__)
+        glsl_version = "#version 150";
+#else
+        glsl_version = "#version 130";
+#endif
+    }
+    IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(bd->GlslVersionString));
+    strcpy(bd->GlslVersionString, glsl_version);
+    strcat(bd->GlslVersionString, "\n");
+
+    // Make an arbitrary GL call (we don't actually need the result)
+    // IF YOU GET A CRASH HERE: it probably means the OpenGL function loader didn't do its job. Let us know!
+    GLint current_texture;
+    glGetIntegerv(GL_TEXTURE_BINDING_2D, &current_texture);
+
+    // Detect extensions we support
+    bd->HasClipOrigin = (bd->GlVersion >= 450);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS
+    GLint num_extensions = 0;
+    glGetIntegerv(GL_NUM_EXTENSIONS, &num_extensions);
+    for (GLint i = 0; i < num_extensions; i++)
+    {
+        const char* extension = (const char*)glGetStringi(GL_EXTENSIONS, i);
+        if (extension != nullptr && strcmp(extension, "GL_ARB_clip_control") == 0)
+            bd->HasClipOrigin = true;
+    }
+#endif
+
+    return true;
+}
+
+void    ImGui_ImplOpenGL3_Shutdown()
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplOpenGL3_DestroyDeviceObjects();
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+void    ImGui_ImplOpenGL3_NewFrame()
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplOpenGL3_Init()?");
+
+    if (!bd->ShaderHandle)
+        ImGui_ImplOpenGL3_CreateDeviceObjects();
+}
+
+static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object)
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+
+    // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
+    glEnable(GL_BLEND);
+    glBlendEquation(GL_FUNC_ADD);
+    glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_STENCIL_TEST);
+    glEnable(GL_SCISSOR_TEST);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
+    if (bd->GlVersion >= 310)
+        glDisable(GL_PRIMITIVE_RESTART);
+#endif
+#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+#endif
+
+    // Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT)
+#if defined(GL_CLIP_ORIGIN)
+    bool clip_origin_lower_left = true;
+    if (bd->HasClipOrigin)
+    {
+        GLenum current_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)&current_clip_origin);
+        if (current_clip_origin == GL_UPPER_LEFT)
+            clip_origin_lower_left = false;
+    }
+#endif
+
+    // Setup viewport, orthographic projection matrix
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
+    GL_CALL(glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height));
+    float L = draw_data->DisplayPos.x;
+    float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+    float T = draw_data->DisplayPos.y;
+    float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+#if defined(GL_CLIP_ORIGIN)
+    if (!clip_origin_lower_left) { float tmp = T; T = B; B = tmp; } // Swap top and bottom if origin is upper left
+#endif
+    const float ortho_projection[4][4] =
+    {
+        { 2.0f/(R-L),   0.0f,         0.0f,   0.0f },
+        { 0.0f,         2.0f/(T-B),   0.0f,   0.0f },
+        { 0.0f,         0.0f,        -1.0f,   0.0f },
+        { (R+L)/(L-R),  (T+B)/(B-T),  0.0f,   1.0f },
+    };
+    glUseProgram(bd->ShaderHandle);
+    glUniform1i(bd->AttribLocationTex, 0);
+    glUniformMatrix4fv(bd->AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
+
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
+    if (bd->GlVersion >= 330 || bd->GlProfileIsES3)
+        glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 and GL ES 3.0 may set that otherwise.
+#endif
+
+    (void)vertex_array_object;
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    glBindVertexArray(vertex_array_object);
+#endif
+
+    // Bind vertex/index buffers and setup attributes for ImDrawVert
+    GL_CALL(glBindBuffer(GL_ARRAY_BUFFER, bd->VboHandle));
+    GL_CALL(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, bd->ElementsHandle));
+    GL_CALL(glEnableVertexAttribArray(bd->AttribLocationVtxPos));
+    GL_CALL(glEnableVertexAttribArray(bd->AttribLocationVtxUV));
+    GL_CALL(glEnableVertexAttribArray(bd->AttribLocationVtxColor));
+    GL_CALL(glVertexAttribPointer(bd->AttribLocationVtxPos,   2, GL_FLOAT,         GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos)));
+    GL_CALL(glVertexAttribPointer(bd->AttribLocationVtxUV,    2, GL_FLOAT,         GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv)));
+    GL_CALL(glVertexAttribPointer(bd->AttribLocationVtxColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col)));
+}
+
+// OpenGL3 Render function.
+// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly.
+// This is in order to be able to run within an OpenGL engine that doesn't do so.
+void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
+{
+    // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+    int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x);
+    int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y);
+    if (fb_width <= 0 || fb_height <= 0)
+        return;
+
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+
+    // Backup GL state
+    GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture);
+    glActiveTexture(GL_TEXTURE0);
+    GLuint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, (GLint*)&last_program);
+    GLuint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, (GLint*)&last_texture);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
+    GLuint last_sampler; if (bd->GlVersion >= 330 || bd->GlProfileIsES3) { glGetIntegerv(GL_SAMPLER_BINDING, (GLint*)&last_sampler); } else { last_sampler = 0; }
+#endif
+    GLuint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, (GLint*)&last_array_buffer);
+#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    // This is part of VAO on OpenGL 3.0+ and OpenGL ES 3.0+.
+    GLint last_element_array_buffer; glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &last_element_array_buffer);
+    ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_pos; last_vtx_attrib_state_pos.GetState(bd->AttribLocationVtxPos);
+    ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_uv; last_vtx_attrib_state_uv.GetState(bd->AttribLocationVtxUV);
+    ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_color; last_vtx_attrib_state_color.GetState(bd->AttribLocationVtxColor);
+#endif
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, (GLint*)&last_vertex_array_object);
+#endif
+#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+    GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
+#endif
+    GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
+    GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
+    GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb);
+    GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb);
+    GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha);
+    GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha);
+    GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb);
+    GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, (GLint*)&last_blend_equation_alpha);
+    GLboolean last_enable_blend = glIsEnabled(GL_BLEND);
+    GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE);
+    GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST);
+    GLboolean last_enable_stencil_test = glIsEnabled(GL_STENCIL_TEST);
+    GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
+    GLboolean last_enable_primitive_restart = (bd->GlVersion >= 310) ? glIsEnabled(GL_PRIMITIVE_RESTART) : GL_FALSE;
+#endif
+
+    // Setup desired GL state
+    // Recreate the VAO every time (this is to easily allow multiple GL contexts to be rendered to. VAO are not shared among GL contexts)
+    // The renderer would actually work without any VAO bound, but then our VertexAttrib calls would overwrite the default one currently bound.
+    GLuint vertex_array_object = 0;
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    GL_CALL(glGenVertexArrays(1, &vertex_array_object));
+#endif
+    ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object);
+
+    // Will project scissor/clipping rectangles into framebuffer space
+    ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
+    ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
+
+    // Render command lists
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+
+        // Upload vertex/index buffers
+        // - OpenGL drivers are in a very sorry state nowadays....
+        //   During 2021 we attempted to switch from glBufferData() to orphaning+glBufferSubData() following reports
+        //   of leaks on Intel GPU when using multi-viewports on Windows.
+        // - After this we kept hearing of various display corruptions issues. We started disabling on non-Intel GPU, but issues still got reported on Intel.
+        // - We are now back to using exclusively glBufferData(). So bd->UseBufferSubData IS ALWAYS FALSE in this code.
+        //   We are keeping the old code path for a while in case people finding new issues may want to test the bd->UseBufferSubData path.
+        // - See https://github.com/ocornut/imgui/issues/4468 and please report any corruption issues.
+        const GLsizeiptr vtx_buffer_size = (GLsizeiptr)cmd_list->VtxBuffer.Size * (int)sizeof(ImDrawVert);
+        const GLsizeiptr idx_buffer_size = (GLsizeiptr)cmd_list->IdxBuffer.Size * (int)sizeof(ImDrawIdx);
+        if (bd->UseBufferSubData)
+        {
+            if (bd->VertexBufferSize < vtx_buffer_size)
+            {
+                bd->VertexBufferSize = vtx_buffer_size;
+                GL_CALL(glBufferData(GL_ARRAY_BUFFER, bd->VertexBufferSize, nullptr, GL_STREAM_DRAW));
+            }
+            if (bd->IndexBufferSize < idx_buffer_size)
+            {
+                bd->IndexBufferSize = idx_buffer_size;
+                GL_CALL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, bd->IndexBufferSize, nullptr, GL_STREAM_DRAW));
+            }
+            GL_CALL(glBufferSubData(GL_ARRAY_BUFFER, 0, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data));
+            GL_CALL(glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data));
+        }
+        else
+        {
+            GL_CALL(glBufferData(GL_ARRAY_BUFFER, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW));
+            GL_CALL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW));
+        }
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback != nullptr)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle (Y is inverted in OpenGL)
+                GL_CALL(glScissor((int)clip_min.x, (int)((float)fb_height - clip_max.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y)));
+
+                // Bind texture, Draw
+                GL_CALL(glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->GetTexID()));
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
+                if (bd->GlVersion >= 320)
+                    GL_CALL(glDrawElementsBaseVertex(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx)), (GLint)pcmd->VtxOffset));
+                else
+#endif
+                GL_CALL(glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx))));
+            }
+        }
+    }
+
+    // Destroy the temporary VAO
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    GL_CALL(glDeleteVertexArrays(1, &vertex_array_object));
+#endif
+
+    // Restore modified GL state
+    // This "glIsProgram()" check is required because if the program is "pending deletion" at the time of binding backup, it will have been deleted by now and will cause an OpenGL error. See #6220.
+    if (last_program == 0 || glIsProgram(last_program)) glUseProgram(last_program);
+    glBindTexture(GL_TEXTURE_2D, last_texture);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
+    if (bd->GlVersion >= 330 || bd->GlProfileIsES3)
+        glBindSampler(0, last_sampler);
+#endif
+    glActiveTexture(last_active_texture);
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    glBindVertexArray(last_vertex_array_object);
+#endif
+    glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
+#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, last_element_array_buffer);
+    last_vtx_attrib_state_pos.SetState(bd->AttribLocationVtxPos);
+    last_vtx_attrib_state_uv.SetState(bd->AttribLocationVtxUV);
+    last_vtx_attrib_state_color.SetState(bd->AttribLocationVtxColor);
+#endif
+    glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
+    glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha);
+    if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND);
+    if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE);
+    if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST);
+    if (last_enable_stencil_test) glEnable(GL_STENCIL_TEST); else glDisable(GL_STENCIL_TEST);
+    if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
+    if (bd->GlVersion >= 310) { if (last_enable_primitive_restart) glEnable(GL_PRIMITIVE_RESTART); else glDisable(GL_PRIMITIVE_RESTART); }
+#endif
+
+#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+    // Desktop OpenGL 3.0 and OpenGL 3.1 had separate polygon draw modes for front-facing and back-facing faces of polygons
+    if (bd->GlVersion <= 310 || bd->GlProfileIsCompat)
+    {
+        glPolygonMode(GL_FRONT, (GLenum)last_polygon_mode[0]);
+        glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1]);
+    }
+    else
+    {
+        glPolygonMode(GL_FRONT_AND_BACK, (GLenum)last_polygon_mode[0]);
+    }
+#endif // IMGUI_IMPL_HAS_POLYGON_MODE
+
+    glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
+    glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]);
+    (void)bd; // Not all compilation paths use this
+}
+
+bool ImGui_ImplOpenGL3_CreateFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+
+    // Build texture atlas
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
+
+    // Upload texture to graphics system
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    GLint last_texture;
+    GL_CALL(glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture));
+    GL_CALL(glGenTextures(1, &bd->FontTexture));
+    GL_CALL(glBindTexture(GL_TEXTURE_2D, bd->FontTexture));
+    GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
+    GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
+#ifdef GL_UNPACK_ROW_LENGTH // Not on WebGL/ES
+    GL_CALL(glPixelStorei(GL_UNPACK_ROW_LENGTH, 0));
+#endif
+    GL_CALL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
+
+    // Restore state
+    GL_CALL(glBindTexture(GL_TEXTURE_2D, last_texture));
+
+    return true;
+}
+
+void ImGui_ImplOpenGL3_DestroyFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    if (bd->FontTexture)
+    {
+        glDeleteTextures(1, &bd->FontTexture);
+        io.Fonts->SetTexID(0);
+        bd->FontTexture = 0;
+    }
+}
+
+// If you get an error please report on github. You may try different GL context version or GLSL version. See GL<>GLSL version table at the top of this file.
+static bool CheckShader(GLuint handle, const char* desc)
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    GLint status = 0, log_length = 0;
+    glGetShaderiv(handle, GL_COMPILE_STATUS, &status);
+    glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &log_length);
+    if ((GLboolean)status == GL_FALSE)
+        fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to compile %s! With GLSL: %s\n", desc, bd->GlslVersionString);
+    if (log_length > 1)
+    {
+        ImVector<char> buf;
+        buf.resize((int)(log_length + 1));
+        glGetShaderInfoLog(handle, log_length, nullptr, (GLchar*)buf.begin());
+        fprintf(stderr, "%s\n", buf.begin());
+    }
+    return (GLboolean)status == GL_TRUE;
+}
+
+// If you get an error please report on GitHub. You may try different GL context version or GLSL version.
+static bool CheckProgram(GLuint handle, const char* desc)
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    GLint status = 0, log_length = 0;
+    glGetProgramiv(handle, GL_LINK_STATUS, &status);
+    glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &log_length);
+    if ((GLboolean)status == GL_FALSE)
+        fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to link %s! With GLSL %s\n", desc, bd->GlslVersionString);
+    if (log_length > 1)
+    {
+        ImVector<char> buf;
+        buf.resize((int)(log_length + 1));
+        glGetProgramInfoLog(handle, log_length, nullptr, (GLchar*)buf.begin());
+        fprintf(stderr, "%s\n", buf.begin());
+    }
+    return (GLboolean)status == GL_TRUE;
+}
+
+bool    ImGui_ImplOpenGL3_CreateDeviceObjects()
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+
+    // Backup GL state
+    GLint last_texture, last_array_buffer;
+    glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
+    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    GLint last_vertex_array;
+    glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
+#endif
+
+    // Parse GLSL version string
+    int glsl_version = 130;
+    sscanf(bd->GlslVersionString, "#version %d", &glsl_version);
+
+    const GLchar* vertex_shader_glsl_120 =
+        "uniform mat4 ProjMtx;\n"
+        "attribute vec2 Position;\n"
+        "attribute vec2 UV;\n"
+        "attribute vec4 Color;\n"
+        "varying vec2 Frag_UV;\n"
+        "varying vec4 Frag_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Frag_UV = UV;\n"
+        "    Frag_Color = Color;\n"
+        "    gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
+        "}\n";
+
+    const GLchar* vertex_shader_glsl_130 =
+        "uniform mat4 ProjMtx;\n"
+        "in vec2 Position;\n"
+        "in vec2 UV;\n"
+        "in vec4 Color;\n"
+        "out vec2 Frag_UV;\n"
+        "out vec4 Frag_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Frag_UV = UV;\n"
+        "    Frag_Color = Color;\n"
+        "    gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
+        "}\n";
+
+    const GLchar* vertex_shader_glsl_300_es =
+        "precision highp float;\n"
+        "layout (location = 0) in vec2 Position;\n"
+        "layout (location = 1) in vec2 UV;\n"
+        "layout (location = 2) in vec4 Color;\n"
+        "uniform mat4 ProjMtx;\n"
+        "out vec2 Frag_UV;\n"
+        "out vec4 Frag_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Frag_UV = UV;\n"
+        "    Frag_Color = Color;\n"
+        "    gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
+        "}\n";
+
+    const GLchar* vertex_shader_glsl_410_core =
+        "layout (location = 0) in vec2 Position;\n"
+        "layout (location = 1) in vec2 UV;\n"
+        "layout (location = 2) in vec4 Color;\n"
+        "uniform mat4 ProjMtx;\n"
+        "out vec2 Frag_UV;\n"
+        "out vec4 Frag_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Frag_UV = UV;\n"
+        "    Frag_Color = Color;\n"
+        "    gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
+        "}\n";
+
+    const GLchar* fragment_shader_glsl_120 =
+        "#ifdef GL_ES\n"
+        "    precision mediump float;\n"
+        "#endif\n"
+        "uniform sampler2D Texture;\n"
+        "varying vec2 Frag_UV;\n"
+        "varying vec4 Frag_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);\n"
+        "}\n";
+
+    const GLchar* fragment_shader_glsl_130 =
+        "uniform sampler2D Texture;\n"
+        "in vec2 Frag_UV;\n"
+        "in vec4 Frag_Color;\n"
+        "out vec4 Out_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"
+        "}\n";
+
+    const GLchar* fragment_shader_glsl_300_es =
+        "precision mediump float;\n"
+        "uniform sampler2D Texture;\n"
+        "in vec2 Frag_UV;\n"
+        "in vec4 Frag_Color;\n"
+        "layout (location = 0) out vec4 Out_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"
+        "}\n";
+
+    const GLchar* fragment_shader_glsl_410_core =
+        "in vec2 Frag_UV;\n"
+        "in vec4 Frag_Color;\n"
+        "uniform sampler2D Texture;\n"
+        "layout (location = 0) out vec4 Out_Color;\n"
+        "void main()\n"
+        "{\n"
+        "    Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"
+        "}\n";
+
+    // Select shaders matching our GLSL versions
+    const GLchar* vertex_shader = nullptr;
+    const GLchar* fragment_shader = nullptr;
+    if (glsl_version < 130)
+    {
+        vertex_shader = vertex_shader_glsl_120;
+        fragment_shader = fragment_shader_glsl_120;
+    }
+    else if (glsl_version >= 410)
+    {
+        vertex_shader = vertex_shader_glsl_410_core;
+        fragment_shader = fragment_shader_glsl_410_core;
+    }
+    else if (glsl_version == 300)
+    {
+        vertex_shader = vertex_shader_glsl_300_es;
+        fragment_shader = fragment_shader_glsl_300_es;
+    }
+    else
+    {
+        vertex_shader = vertex_shader_glsl_130;
+        fragment_shader = fragment_shader_glsl_130;
+    }
+
+    // Create shaders
+    const GLchar* vertex_shader_with_version[2] = { bd->GlslVersionString, vertex_shader };
+    GLuint vert_handle = glCreateShader(GL_VERTEX_SHADER);
+    glShaderSource(vert_handle, 2, vertex_shader_with_version, nullptr);
+    glCompileShader(vert_handle);
+    CheckShader(vert_handle, "vertex shader");
+
+    const GLchar* fragment_shader_with_version[2] = { bd->GlslVersionString, fragment_shader };
+    GLuint frag_handle = glCreateShader(GL_FRAGMENT_SHADER);
+    glShaderSource(frag_handle, 2, fragment_shader_with_version, nullptr);
+    glCompileShader(frag_handle);
+    CheckShader(frag_handle, "fragment shader");
+
+    // Link
+    bd->ShaderHandle = glCreateProgram();
+    glAttachShader(bd->ShaderHandle, vert_handle);
+    glAttachShader(bd->ShaderHandle, frag_handle);
+    glLinkProgram(bd->ShaderHandle);
+    CheckProgram(bd->ShaderHandle, "shader program");
+
+    glDetachShader(bd->ShaderHandle, vert_handle);
+    glDetachShader(bd->ShaderHandle, frag_handle);
+    glDeleteShader(vert_handle);
+    glDeleteShader(frag_handle);
+
+    bd->AttribLocationTex = glGetUniformLocation(bd->ShaderHandle, "Texture");
+    bd->AttribLocationProjMtx = glGetUniformLocation(bd->ShaderHandle, "ProjMtx");
+    bd->AttribLocationVtxPos = (GLuint)glGetAttribLocation(bd->ShaderHandle, "Position");
+    bd->AttribLocationVtxUV = (GLuint)glGetAttribLocation(bd->ShaderHandle, "UV");
+    bd->AttribLocationVtxColor = (GLuint)glGetAttribLocation(bd->ShaderHandle, "Color");
+
+    // Create buffers
+    glGenBuffers(1, &bd->VboHandle);
+    glGenBuffers(1, &bd->ElementsHandle);
+
+    ImGui_ImplOpenGL3_CreateFontsTexture();
+
+    // Restore modified GL state
+    glBindTexture(GL_TEXTURE_2D, last_texture);
+    glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
+#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
+    glBindVertexArray(last_vertex_array);
+#endif
+
+    return true;
+}
+
+void    ImGui_ImplOpenGL3_DestroyDeviceObjects()
+{
+    ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData();
+    if (bd->VboHandle)      { glDeleteBuffers(1, &bd->VboHandle); bd->VboHandle = 0; }
+    if (bd->ElementsHandle) { glDeleteBuffers(1, &bd->ElementsHandle); bd->ElementsHandle = 0; }
+    if (bd->ShaderHandle)   { glDeleteProgram(bd->ShaderHandle); bd->ShaderHandle = 0; }
+    ImGui_ImplOpenGL3_DestroyFontsTexture();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_opengl3.h

@@ -0,0 +1,66 @@
+// dear imgui: Renderer Backend for modern OpenGL with shaders / programmatic pipeline
+// - Desktop GL: 2.x 3.x 4.x
+// - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0)
+// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
+
+// About WebGL/ES:
+// - You need to '#define IMGUI_IMPL_OPENGL_ES2' or '#define IMGUI_IMPL_OPENGL_ES3' to use WebGL or OpenGL ES.
+// - This is done automatically on iOS, Android and Emscripten targets.
+// - For other targets, the define needs to be visible from the imgui_impl_opengl3.cpp compilation unit. If unsure, define globally or in imconfig.h.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// About GLSL version:
+//  The 'glsl_version' initialization parameter should be nullptr (default) or a "#version XXX" string.
+//  On computer platform the GLSL version default to "#version 130". On OpenGL ES 3 platform it defaults to "#version 300 es"
+//  Only override if your GL version doesn't handle this GLSL version. See GLSL version table at the top of imgui_impl_opengl3.cpp.
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+// Backend API
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_Init(const char* glsl_version = nullptr);
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data);
+
+// (Optional) Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_DestroyDeviceObjects();
+
+// Specific OpenGL ES versions
+//#define IMGUI_IMPL_OPENGL_ES2     // Auto-detected on Emscripten
+//#define IMGUI_IMPL_OPENGL_ES3     // Auto-detected on iOS/Android
+
+// You can explicitly select GLES2 or GLES3 API by using one of the '#define IMGUI_IMPL_OPENGL_LOADER_XXX' in imconfig.h or compiler command-line.
+#if !defined(IMGUI_IMPL_OPENGL_ES2) \
+ && !defined(IMGUI_IMPL_OPENGL_ES3)
+
+// Try to detect GLES on matching platforms
+#if defined(__APPLE__)
+#include <TargetConditionals.h>
+#endif
+#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV)) || (defined(__ANDROID__))
+#define IMGUI_IMPL_OPENGL_ES3               // iOS, Android  -> GL ES 3, "#version 300 es"
+#elif defined(__EMSCRIPTEN__) || defined(__amigaos4__)
+#define IMGUI_IMPL_OPENGL_ES2               // Emscripten    -> GL ES 2, "#version 100"
+#else
+// Otherwise imgui_impl_opengl3_loader.h will be used.
+#endif
+
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_opengl3_loader.h

@@ -0,0 +1,809 @@
+//-----------------------------------------------------------------------------
+// About imgui_impl_opengl3_loader.h:
+//
+// We embed our own OpenGL loader to not require user to provide their own or to have to use ours,
+// which proved to be endless problems for users.
+// Our loader is custom-generated, based on gl3w but automatically filtered to only include
+// enums/functions that we use in our imgui_impl_opengl3.cpp source file in order to be small.
+//
+// YOU SHOULD NOT NEED TO INCLUDE/USE THIS DIRECTLY. THIS IS USED BY imgui_impl_opengl3.cpp ONLY.
+// THE REST OF YOUR APP SHOULD USE A DIFFERENT GL LOADER: ANY GL LOADER OF YOUR CHOICE.
+//
+// IF YOU GET BUILD ERRORS IN THIS FILE (commonly macro redefinitions or function redefinitions):
+// IT LIKELY MEANS THAT YOU ARE BUILDING 'imgui_impl_opengl3.cpp' OR INCUDING 'imgui_impl_opengl3_loader.h'
+// IN THE SAME COMPILATION UNIT AS ONE OF YOUR FILE WHICH IS USING A THIRD-PARTY OPENGL LOADER.
+// (e.g. COULD HAPPEN IF YOU ARE DOING A UNITY/JUMBO BUILD, OR INCLUDING .CPP FILES FROM OTHERS)
+// YOU SHOULD NOT BUILD BOTH IN THE SAME COMPILATION UNIT.
+// BUT IF YOU REALLY WANT TO, you can '#define IMGUI_IMPL_OPENGL_LOADER_CUSTOM' and imgui_impl_opengl3.cpp
+// WILL NOT BE USING OUR LOADER, AND INSTEAD EXPECT ANOTHER/YOUR LOADER TO BE AVAILABLE IN THE COMPILATION UNIT.
+//
+// Regenerate with:
+//   python gl3w_gen.py --output ../imgui/backends/imgui_impl_opengl3_loader.h --ref ../imgui/backends/imgui_impl_opengl3.cpp ./extra_symbols.txt
+//
+// More info:
+//   https://github.com/dearimgui/gl3w_stripped
+//   https://github.com/ocornut/imgui/issues/4445
+//-----------------------------------------------------------------------------
+
+/*
+ * This file was generated with gl3w_gen.py, part of imgl3w
+ * (hosted at https://github.com/dearimgui/gl3w_stripped)
+ *
+ * This is free and unencumbered software released into the public domain.
+ *
+ * Anyone is free to copy, modify, publish, use, compile, sell, or
+ * distribute this software, either in source code form or as a compiled
+ * binary, for any purpose, commercial or non-commercial, and by any
+ * means.
+ *
+ * In jurisdictions that recognize copyright laws, the author or authors
+ * of this software dedicate any and all copyright interest in the
+ * software to the public domain. We make this dedication for the benefit
+ * of the public at large and to the detriment of our heirs and
+ * successors. We intend this dedication to be an overt act of
+ * relinquishment in perpetuity of all present and future rights to this
+ * software under copyright law.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __gl3w_h_
+#define __gl3w_h_
+
+// Adapted from KHR/khrplatform.h to avoid including entire file.
+#ifndef __khrplatform_h_
+typedef          float         khronos_float_t;
+typedef signed   char          khronos_int8_t;
+typedef unsigned char          khronos_uint8_t;
+typedef signed   short int     khronos_int16_t;
+typedef unsigned short int     khronos_uint16_t;
+#ifdef _WIN64
+typedef signed   long long int khronos_intptr_t;
+typedef signed   long long int khronos_ssize_t;
+#else
+typedef signed   long  int     khronos_intptr_t;
+typedef signed   long  int     khronos_ssize_t;
+#endif
+
+#if defined(_MSC_VER) && !defined(__clang__)
+typedef signed   __int64       khronos_int64_t;
+typedef unsigned __int64       khronos_uint64_t;
+#elif (defined(__clang__) || defined(__GNUC__)) && (__cplusplus < 201100)
+#include <stdint.h>
+typedef          int64_t       khronos_int64_t;
+typedef          uint64_t      khronos_uint64_t;
+#else
+typedef signed   long long     khronos_int64_t;
+typedef unsigned long long     khronos_uint64_t;
+#endif
+#endif  // __khrplatform_h_
+
+#ifndef __gl_glcorearb_h_
+#define __gl_glcorearb_h_ 1
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+** Copyright 2013-2020 The Khronos Group Inc.
+** SPDX-License-Identifier: MIT
+**
+** This header is generated from the Khronos OpenGL / OpenGL ES XML
+** API Registry. The current version of the Registry, generator scripts
+** used to make the header, and the header can be found at
+**   https://github.com/KhronosGroup/OpenGL-Registry
+*/
+#if defined(_WIN32) && !defined(APIENTRY) && !defined(__CYGWIN__) && !defined(__SCITECH_SNAP__)
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN 1
+#endif
+#include <windows.h>
+#endif
+#ifndef APIENTRY
+#define APIENTRY
+#endif
+#ifndef APIENTRYP
+#define APIENTRYP APIENTRY *
+#endif
+#ifndef GLAPI
+#define GLAPI extern
+#endif
+/* glcorearb.h is for use with OpenGL core profile implementations.
+** It should should be placed in the same directory as gl.h and
+** included as <GL/glcorearb.h>.
+**
+** glcorearb.h includes only APIs in the latest OpenGL core profile
+** implementation together with APIs in newer ARB extensions which 
+** can be supported by the core profile. It does not, and never will
+** include functionality removed from the core profile, such as
+** fixed-function vertex and fragment processing.
+**
+** Do not #include both <GL/glcorearb.h> and either of <GL/gl.h> or
+** <GL/glext.h> in the same source file.
+*/
+/* Generated C header for:
+ * API: gl
+ * Profile: core
+ * Versions considered: .*
+ * Versions emitted: .*
+ * Default extensions included: glcore
+ * Additional extensions included: _nomatch_^
+ * Extensions removed: _nomatch_^
+ */
+#ifndef GL_VERSION_1_0
+typedef void GLvoid;
+typedef unsigned int GLenum;
+
+typedef khronos_float_t GLfloat;
+typedef int GLint;
+typedef int GLsizei;
+typedef unsigned int GLbitfield;
+typedef double GLdouble;
+typedef unsigned int GLuint;
+typedef unsigned char GLboolean;
+typedef khronos_uint8_t GLubyte;
+#define GL_COLOR_BUFFER_BIT               0x00004000
+#define GL_FALSE                          0
+#define GL_TRUE                           1
+#define GL_TRIANGLES                      0x0004
+#define GL_ONE                            1
+#define GL_SRC_ALPHA                      0x0302
+#define GL_ONE_MINUS_SRC_ALPHA            0x0303
+#define GL_FRONT                          0x0404
+#define GL_BACK                           0x0405
+#define GL_FRONT_AND_BACK                 0x0408
+#define GL_POLYGON_MODE                   0x0B40
+#define GL_CULL_FACE                      0x0B44
+#define GL_DEPTH_TEST                     0x0B71
+#define GL_STENCIL_TEST                   0x0B90
+#define GL_VIEWPORT                       0x0BA2
+#define GL_BLEND                          0x0BE2
+#define GL_SCISSOR_BOX                    0x0C10
+#define GL_SCISSOR_TEST                   0x0C11
+#define GL_UNPACK_ROW_LENGTH              0x0CF2
+#define GL_PACK_ALIGNMENT                 0x0D05
+#define GL_TEXTURE_2D                     0x0DE1
+#define GL_UNSIGNED_BYTE                  0x1401
+#define GL_UNSIGNED_SHORT                 0x1403
+#define GL_UNSIGNED_INT                   0x1405
+#define GL_FLOAT                          0x1406
+#define GL_RGBA                           0x1908
+#define GL_FILL                           0x1B02
+#define GL_VENDOR                         0x1F00
+#define GL_RENDERER                       0x1F01
+#define GL_VERSION                        0x1F02
+#define GL_EXTENSIONS                     0x1F03
+#define GL_LINEAR                         0x2601
+#define GL_TEXTURE_MAG_FILTER             0x2800
+#define GL_TEXTURE_MIN_FILTER             0x2801
+typedef void (APIENTRYP PFNGLPOLYGONMODEPROC) (GLenum face, GLenum mode);
+typedef void (APIENTRYP PFNGLSCISSORPROC) (GLint x, GLint y, GLsizei width, GLsizei height);
+typedef void (APIENTRYP PFNGLTEXPARAMETERIPROC) (GLenum target, GLenum pname, GLint param);
+typedef void (APIENTRYP PFNGLTEXIMAGE2DPROC) (GLenum target, GLint level, GLint internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const void *pixels);
+typedef void (APIENTRYP PFNGLCLEARPROC) (GLbitfield mask);
+typedef void (APIENTRYP PFNGLCLEARCOLORPROC) (GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);
+typedef void (APIENTRYP PFNGLDISABLEPROC) (GLenum cap);
+typedef void (APIENTRYP PFNGLENABLEPROC) (GLenum cap);
+typedef void (APIENTRYP PFNGLFLUSHPROC) (void);
+typedef void (APIENTRYP PFNGLPIXELSTOREIPROC) (GLenum pname, GLint param);
+typedef void (APIENTRYP PFNGLREADPIXELSPROC) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, void *pixels);
+typedef GLenum (APIENTRYP PFNGLGETERRORPROC) (void);
+typedef void (APIENTRYP PFNGLGETINTEGERVPROC) (GLenum pname, GLint *data);
+typedef const GLubyte *(APIENTRYP PFNGLGETSTRINGPROC) (GLenum name);
+typedef GLboolean (APIENTRYP PFNGLISENABLEDPROC) (GLenum cap);
+typedef void (APIENTRYP PFNGLVIEWPORTPROC) (GLint x, GLint y, GLsizei width, GLsizei height);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glPolygonMode (GLenum face, GLenum mode);
+GLAPI void APIENTRY glScissor (GLint x, GLint y, GLsizei width, GLsizei height);
+GLAPI void APIENTRY glTexParameteri (GLenum target, GLenum pname, GLint param);
+GLAPI void APIENTRY glTexImage2D (GLenum target, GLint level, GLint internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const void *pixels);
+GLAPI void APIENTRY glClear (GLbitfield mask);
+GLAPI void APIENTRY glClearColor (GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);
+GLAPI void APIENTRY glDisable (GLenum cap);
+GLAPI void APIENTRY glEnable (GLenum cap);
+GLAPI void APIENTRY glFlush (void);
+GLAPI void APIENTRY glPixelStorei (GLenum pname, GLint param);
+GLAPI void APIENTRY glReadPixels (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, void *pixels);
+GLAPI GLenum APIENTRY glGetError (void);
+GLAPI void APIENTRY glGetIntegerv (GLenum pname, GLint *data);
+GLAPI const GLubyte *APIENTRY glGetString (GLenum name);
+GLAPI GLboolean APIENTRY glIsEnabled (GLenum cap);
+GLAPI void APIENTRY glViewport (GLint x, GLint y, GLsizei width, GLsizei height);
+#endif
+#endif /* GL_VERSION_1_0 */
+#ifndef GL_VERSION_1_1
+typedef khronos_float_t GLclampf;
+typedef double GLclampd;
+#define GL_TEXTURE_BINDING_2D             0x8069
+typedef void (APIENTRYP PFNGLDRAWELEMENTSPROC) (GLenum mode, GLsizei count, GLenum type, const void *indices);
+typedef void (APIENTRYP PFNGLBINDTEXTUREPROC) (GLenum target, GLuint texture);
+typedef void (APIENTRYP PFNGLDELETETEXTURESPROC) (GLsizei n, const GLuint *textures);
+typedef void (APIENTRYP PFNGLGENTEXTURESPROC) (GLsizei n, GLuint *textures);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glDrawElements (GLenum mode, GLsizei count, GLenum type, const void *indices);
+GLAPI void APIENTRY glBindTexture (GLenum target, GLuint texture);
+GLAPI void APIENTRY glDeleteTextures (GLsizei n, const GLuint *textures);
+GLAPI void APIENTRY glGenTextures (GLsizei n, GLuint *textures);
+#endif
+#endif /* GL_VERSION_1_1 */
+#ifndef GL_VERSION_1_3
+#define GL_TEXTURE0                       0x84C0
+#define GL_ACTIVE_TEXTURE                 0x84E0
+typedef void (APIENTRYP PFNGLACTIVETEXTUREPROC) (GLenum texture);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glActiveTexture (GLenum texture);
+#endif
+#endif /* GL_VERSION_1_3 */
+#ifndef GL_VERSION_1_4
+#define GL_BLEND_DST_RGB                  0x80C8
+#define GL_BLEND_SRC_RGB                  0x80C9
+#define GL_BLEND_DST_ALPHA                0x80CA
+#define GL_BLEND_SRC_ALPHA                0x80CB
+#define GL_FUNC_ADD                       0x8006
+typedef void (APIENTRYP PFNGLBLENDFUNCSEPARATEPROC) (GLenum sfactorRGB, GLenum dfactorRGB, GLenum sfactorAlpha, GLenum dfactorAlpha);
+typedef void (APIENTRYP PFNGLBLENDEQUATIONPROC) (GLenum mode);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glBlendFuncSeparate (GLenum sfactorRGB, GLenum dfactorRGB, GLenum sfactorAlpha, GLenum dfactorAlpha);
+GLAPI void APIENTRY glBlendEquation (GLenum mode);
+#endif
+#endif /* GL_VERSION_1_4 */
+#ifndef GL_VERSION_1_5
+typedef khronos_ssize_t GLsizeiptr;
+typedef khronos_intptr_t GLintptr;
+#define GL_ARRAY_BUFFER                   0x8892
+#define GL_ELEMENT_ARRAY_BUFFER           0x8893
+#define GL_ARRAY_BUFFER_BINDING           0x8894
+#define GL_ELEMENT_ARRAY_BUFFER_BINDING   0x8895
+#define GL_STREAM_DRAW                    0x88E0
+typedef void (APIENTRYP PFNGLBINDBUFFERPROC) (GLenum target, GLuint buffer);
+typedef void (APIENTRYP PFNGLDELETEBUFFERSPROC) (GLsizei n, const GLuint *buffers);
+typedef void (APIENTRYP PFNGLGENBUFFERSPROC) (GLsizei n, GLuint *buffers);
+typedef void (APIENTRYP PFNGLBUFFERDATAPROC) (GLenum target, GLsizeiptr size, const void *data, GLenum usage);
+typedef void (APIENTRYP PFNGLBUFFERSUBDATAPROC) (GLenum target, GLintptr offset, GLsizeiptr size, const void *data);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glBindBuffer (GLenum target, GLuint buffer);
+GLAPI void APIENTRY glDeleteBuffers (GLsizei n, const GLuint *buffers);
+GLAPI void APIENTRY glGenBuffers (GLsizei n, GLuint *buffers);
+GLAPI void APIENTRY glBufferData (GLenum target, GLsizeiptr size, const void *data, GLenum usage);
+GLAPI void APIENTRY glBufferSubData (GLenum target, GLintptr offset, GLsizeiptr size, const void *data);
+#endif
+#endif /* GL_VERSION_1_5 */
+#ifndef GL_VERSION_2_0
+typedef char GLchar;
+typedef khronos_int16_t GLshort;
+typedef khronos_int8_t GLbyte;
+typedef khronos_uint16_t GLushort;
+#define GL_BLEND_EQUATION_RGB             0x8009
+#define GL_VERTEX_ATTRIB_ARRAY_ENABLED    0x8622
+#define GL_VERTEX_ATTRIB_ARRAY_SIZE       0x8623
+#define GL_VERTEX_ATTRIB_ARRAY_STRIDE     0x8624
+#define GL_VERTEX_ATTRIB_ARRAY_TYPE       0x8625
+#define GL_VERTEX_ATTRIB_ARRAY_POINTER    0x8645
+#define GL_BLEND_EQUATION_ALPHA           0x883D
+#define GL_VERTEX_ATTRIB_ARRAY_NORMALIZED 0x886A
+#define GL_FRAGMENT_SHADER                0x8B30
+#define GL_VERTEX_SHADER                  0x8B31
+#define GL_COMPILE_STATUS                 0x8B81
+#define GL_LINK_STATUS                    0x8B82
+#define GL_INFO_LOG_LENGTH                0x8B84
+#define GL_CURRENT_PROGRAM                0x8B8D
+#define GL_UPPER_LEFT                     0x8CA2
+typedef void (APIENTRYP PFNGLBLENDEQUATIONSEPARATEPROC) (GLenum modeRGB, GLenum modeAlpha);
+typedef void (APIENTRYP PFNGLATTACHSHADERPROC) (GLuint program, GLuint shader);
+typedef void (APIENTRYP PFNGLCOMPILESHADERPROC) (GLuint shader);
+typedef GLuint (APIENTRYP PFNGLCREATEPROGRAMPROC) (void);
+typedef GLuint (APIENTRYP PFNGLCREATESHADERPROC) (GLenum type);
+typedef void (APIENTRYP PFNGLDELETEPROGRAMPROC) (GLuint program);
+typedef void (APIENTRYP PFNGLDELETESHADERPROC) (GLuint shader);
+typedef void (APIENTRYP PFNGLDETACHSHADERPROC) (GLuint program, GLuint shader);
+typedef void (APIENTRYP PFNGLDISABLEVERTEXATTRIBARRAYPROC) (GLuint index);
+typedef void (APIENTRYP PFNGLENABLEVERTEXATTRIBARRAYPROC) (GLuint index);
+typedef GLint (APIENTRYP PFNGLGETATTRIBLOCATIONPROC) (GLuint program, const GLchar *name);
+typedef void (APIENTRYP PFNGLGETPROGRAMIVPROC) (GLuint program, GLenum pname, GLint *params);
+typedef void (APIENTRYP PFNGLGETPROGRAMINFOLOGPROC) (GLuint program, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
+typedef void (APIENTRYP PFNGLGETSHADERIVPROC) (GLuint shader, GLenum pname, GLint *params);
+typedef void (APIENTRYP PFNGLGETSHADERINFOLOGPROC) (GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
+typedef GLint (APIENTRYP PFNGLGETUNIFORMLOCATIONPROC) (GLuint program, const GLchar *name);
+typedef void (APIENTRYP PFNGLGETVERTEXATTRIBIVPROC) (GLuint index, GLenum pname, GLint *params);
+typedef void (APIENTRYP PFNGLGETVERTEXATTRIBPOINTERVPROC) (GLuint index, GLenum pname, void **pointer);
+typedef GLboolean (APIENTRYP PFNGLISPROGRAMPROC) (GLuint program);
+typedef void (APIENTRYP PFNGLLINKPROGRAMPROC) (GLuint program);
+typedef void (APIENTRYP PFNGLSHADERSOURCEPROC) (GLuint shader, GLsizei count, const GLchar *const*string, const GLint *length);
+typedef void (APIENTRYP PFNGLUSEPROGRAMPROC) (GLuint program);
+typedef void (APIENTRYP PFNGLUNIFORM1IPROC) (GLint location, GLint v0);
+typedef void (APIENTRYP PFNGLUNIFORMMATRIX4FVPROC) (GLint location, GLsizei count, GLboolean transpose, const GLfloat *value);
+typedef void (APIENTRYP PFNGLVERTEXATTRIBPOINTERPROC) (GLuint index, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const void *pointer);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glBlendEquationSeparate (GLenum modeRGB, GLenum modeAlpha);
+GLAPI void APIENTRY glAttachShader (GLuint program, GLuint shader);
+GLAPI void APIENTRY glCompileShader (GLuint shader);
+GLAPI GLuint APIENTRY glCreateProgram (void);
+GLAPI GLuint APIENTRY glCreateShader (GLenum type);
+GLAPI void APIENTRY glDeleteProgram (GLuint program);
+GLAPI void APIENTRY glDeleteShader (GLuint shader);
+GLAPI void APIENTRY glDetachShader (GLuint program, GLuint shader);
+GLAPI void APIENTRY glDisableVertexAttribArray (GLuint index);
+GLAPI void APIENTRY glEnableVertexAttribArray (GLuint index);
+GLAPI GLint APIENTRY glGetAttribLocation (GLuint program, const GLchar *name);
+GLAPI void APIENTRY glGetProgramiv (GLuint program, GLenum pname, GLint *params);
+GLAPI void APIENTRY glGetProgramInfoLog (GLuint program, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
+GLAPI void APIENTRY glGetShaderiv (GLuint shader, GLenum pname, GLint *params);
+GLAPI void APIENTRY glGetShaderInfoLog (GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
+GLAPI GLint APIENTRY glGetUniformLocation (GLuint program, const GLchar *name);
+GLAPI void APIENTRY glGetVertexAttribiv (GLuint index, GLenum pname, GLint *params);
+GLAPI void APIENTRY glGetVertexAttribPointerv (GLuint index, GLenum pname, void **pointer);
+GLAPI GLboolean APIENTRY glIsProgram (GLuint program);
+GLAPI void APIENTRY glLinkProgram (GLuint program);
+GLAPI void APIENTRY glShaderSource (GLuint shader, GLsizei count, const GLchar *const*string, const GLint *length);
+GLAPI void APIENTRY glUseProgram (GLuint program);
+GLAPI void APIENTRY glUniform1i (GLint location, GLint v0);
+GLAPI void APIENTRY glUniformMatrix4fv (GLint location, GLsizei count, GLboolean transpose, const GLfloat *value);
+GLAPI void APIENTRY glVertexAttribPointer (GLuint index, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const void *pointer);
+#endif
+#endif /* GL_VERSION_2_0 */
+#ifndef GL_VERSION_3_0
+typedef khronos_uint16_t GLhalf;
+#define GL_MAJOR_VERSION                  0x821B
+#define GL_MINOR_VERSION                  0x821C
+#define GL_NUM_EXTENSIONS                 0x821D
+#define GL_FRAMEBUFFER_SRGB               0x8DB9
+#define GL_VERTEX_ARRAY_BINDING           0x85B5
+typedef void (APIENTRYP PFNGLGETBOOLEANI_VPROC) (GLenum target, GLuint index, GLboolean *data);
+typedef void (APIENTRYP PFNGLGETINTEGERI_VPROC) (GLenum target, GLuint index, GLint *data);
+typedef const GLubyte *(APIENTRYP PFNGLGETSTRINGIPROC) (GLenum name, GLuint index);
+typedef void (APIENTRYP PFNGLBINDVERTEXARRAYPROC) (GLuint array);
+typedef void (APIENTRYP PFNGLDELETEVERTEXARRAYSPROC) (GLsizei n, const GLuint *arrays);
+typedef void (APIENTRYP PFNGLGENVERTEXARRAYSPROC) (GLsizei n, GLuint *arrays);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI const GLubyte *APIENTRY glGetStringi (GLenum name, GLuint index);
+GLAPI void APIENTRY glBindVertexArray (GLuint array);
+GLAPI void APIENTRY glDeleteVertexArrays (GLsizei n, const GLuint *arrays);
+GLAPI void APIENTRY glGenVertexArrays (GLsizei n, GLuint *arrays);
+#endif
+#endif /* GL_VERSION_3_0 */
+#ifndef GL_VERSION_3_1
+#define GL_VERSION_3_1 1
+#define GL_PRIMITIVE_RESTART              0x8F9D
+#endif /* GL_VERSION_3_1 */
+#ifndef GL_VERSION_3_2
+#define GL_VERSION_3_2 1
+typedef struct __GLsync *GLsync;
+typedef khronos_uint64_t GLuint64;
+typedef khronos_int64_t GLint64;
+#define GL_CONTEXT_COMPATIBILITY_PROFILE_BIT 0x00000002
+#define GL_CONTEXT_PROFILE_MASK           0x9126
+typedef void (APIENTRYP PFNGLDRAWELEMENTSBASEVERTEXPROC) (GLenum mode, GLsizei count, GLenum type, const void *indices, GLint basevertex);
+typedef void (APIENTRYP PFNGLGETINTEGER64I_VPROC) (GLenum target, GLuint index, GLint64 *data);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glDrawElementsBaseVertex (GLenum mode, GLsizei count, GLenum type, const void *indices, GLint basevertex);
+#endif
+#endif /* GL_VERSION_3_2 */
+#ifndef GL_VERSION_3_3
+#define GL_VERSION_3_3 1
+#define GL_SAMPLER_BINDING                0x8919
+typedef void (APIENTRYP PFNGLBINDSAMPLERPROC) (GLuint unit, GLuint sampler);
+#ifdef GL_GLEXT_PROTOTYPES
+GLAPI void APIENTRY glBindSampler (GLuint unit, GLuint sampler);
+#endif
+#endif /* GL_VERSION_3_3 */
+#ifndef GL_VERSION_4_1
+typedef void (APIENTRYP PFNGLGETFLOATI_VPROC) (GLenum target, GLuint index, GLfloat *data);
+typedef void (APIENTRYP PFNGLGETDOUBLEI_VPROC) (GLenum target, GLuint index, GLdouble *data);
+#endif /* GL_VERSION_4_1 */
+#ifndef GL_VERSION_4_3
+typedef void (APIENTRY  *GLDEBUGPROC)(GLenum source,GLenum type,GLuint id,GLenum severity,GLsizei length,const GLchar *message,const void *userParam);
+#endif /* GL_VERSION_4_3 */
+#ifndef GL_VERSION_4_5
+#define GL_CLIP_ORIGIN                    0x935C
+typedef void (APIENTRYP PFNGLGETTRANSFORMFEEDBACKI_VPROC) (GLuint xfb, GLenum pname, GLuint index, GLint *param);
+typedef void (APIENTRYP PFNGLGETTRANSFORMFEEDBACKI64_VPROC) (GLuint xfb, GLenum pname, GLuint index, GLint64 *param);
+#endif /* GL_VERSION_4_5 */
+#ifndef GL_ARB_bindless_texture
+typedef khronos_uint64_t GLuint64EXT;
+#endif /* GL_ARB_bindless_texture */
+#ifndef GL_ARB_cl_event
+struct _cl_context;
+struct _cl_event;
+#endif /* GL_ARB_cl_event */
+#ifndef GL_ARB_clip_control
+#define GL_ARB_clip_control 1
+#endif /* GL_ARB_clip_control */
+#ifndef GL_ARB_debug_output
+typedef void (APIENTRY  *GLDEBUGPROCARB)(GLenum source,GLenum type,GLuint id,GLenum severity,GLsizei length,const GLchar *message,const void *userParam);
+#endif /* GL_ARB_debug_output */
+#ifndef GL_EXT_EGL_image_storage
+typedef void *GLeglImageOES;
+#endif /* GL_EXT_EGL_image_storage */
+#ifndef GL_EXT_direct_state_access
+typedef void (APIENTRYP PFNGLGETFLOATI_VEXTPROC) (GLenum pname, GLuint index, GLfloat *params);
+typedef void (APIENTRYP PFNGLGETDOUBLEI_VEXTPROC) (GLenum pname, GLuint index, GLdouble *params);
+typedef void (APIENTRYP PFNGLGETPOINTERI_VEXTPROC) (GLenum pname, GLuint index, void **params);
+typedef void (APIENTRYP PFNGLGETVERTEXARRAYINTEGERI_VEXTPROC) (GLuint vaobj, GLuint index, GLenum pname, GLint *param);
+typedef void (APIENTRYP PFNGLGETVERTEXARRAYPOINTERI_VEXTPROC) (GLuint vaobj, GLuint index, GLenum pname, void **param);
+#endif /* GL_EXT_direct_state_access */
+#ifndef GL_NV_draw_vulkan_image
+typedef void (APIENTRY  *GLVULKANPROCNV)(void);
+#endif /* GL_NV_draw_vulkan_image */
+#ifndef GL_NV_gpu_shader5
+typedef khronos_int64_t GLint64EXT;
+#endif /* GL_NV_gpu_shader5 */
+#ifndef GL_NV_vertex_buffer_unified_memory
+typedef void (APIENTRYP PFNGLGETINTEGERUI64I_VNVPROC) (GLenum value, GLuint index, GLuint64EXT *result);
+#endif /* GL_NV_vertex_buffer_unified_memory */
+#ifdef __cplusplus
+}
+#endif
+#endif
+
+#ifndef GL3W_API
+#define GL3W_API
+#endif
+
+#ifndef __gl_h_
+#define __gl_h_
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define GL3W_OK 0
+#define GL3W_ERROR_INIT -1
+#define GL3W_ERROR_LIBRARY_OPEN -2
+#define GL3W_ERROR_OPENGL_VERSION -3
+
+typedef void (*GL3WglProc)(void);
+typedef GL3WglProc (*GL3WGetProcAddressProc)(const char *proc);
+
+/* gl3w api */
+GL3W_API int imgl3wInit(void);
+GL3W_API int imgl3wInit2(GL3WGetProcAddressProc proc);
+GL3W_API int imgl3wIsSupported(int major, int minor);
+GL3W_API GL3WglProc imgl3wGetProcAddress(const char *proc);
+
+/* gl3w internal state */
+union GL3WProcs {
+    GL3WglProc ptr[59];
+    struct {
+        PFNGLACTIVETEXTUREPROC            ActiveTexture;
+        PFNGLATTACHSHADERPROC             AttachShader;
+        PFNGLBINDBUFFERPROC               BindBuffer;
+        PFNGLBINDSAMPLERPROC              BindSampler;
+        PFNGLBINDTEXTUREPROC              BindTexture;
+        PFNGLBINDVERTEXARRAYPROC          BindVertexArray;
+        PFNGLBLENDEQUATIONPROC            BlendEquation;
+        PFNGLBLENDEQUATIONSEPARATEPROC    BlendEquationSeparate;
+        PFNGLBLENDFUNCSEPARATEPROC        BlendFuncSeparate;
+        PFNGLBUFFERDATAPROC               BufferData;
+        PFNGLBUFFERSUBDATAPROC            BufferSubData;
+        PFNGLCLEARPROC                    Clear;
+        PFNGLCLEARCOLORPROC               ClearColor;
+        PFNGLCOMPILESHADERPROC            CompileShader;
+        PFNGLCREATEPROGRAMPROC            CreateProgram;
+        PFNGLCREATESHADERPROC             CreateShader;
+        PFNGLDELETEBUFFERSPROC            DeleteBuffers;
+        PFNGLDELETEPROGRAMPROC            DeleteProgram;
+        PFNGLDELETESHADERPROC             DeleteShader;
+        PFNGLDELETETEXTURESPROC           DeleteTextures;
+        PFNGLDELETEVERTEXARRAYSPROC       DeleteVertexArrays;
+        PFNGLDETACHSHADERPROC             DetachShader;
+        PFNGLDISABLEPROC                  Disable;
+        PFNGLDISABLEVERTEXATTRIBARRAYPROC DisableVertexAttribArray;
+        PFNGLDRAWELEMENTSPROC             DrawElements;
+        PFNGLDRAWELEMENTSBASEVERTEXPROC   DrawElementsBaseVertex;
+        PFNGLENABLEPROC                   Enable;
+        PFNGLENABLEVERTEXATTRIBARRAYPROC  EnableVertexAttribArray;
+        PFNGLFLUSHPROC                    Flush;
+        PFNGLGENBUFFERSPROC               GenBuffers;
+        PFNGLGENTEXTURESPROC              GenTextures;
+        PFNGLGENVERTEXARRAYSPROC          GenVertexArrays;
+        PFNGLGETATTRIBLOCATIONPROC        GetAttribLocation;
+        PFNGLGETERRORPROC                 GetError;
+        PFNGLGETINTEGERVPROC              GetIntegerv;
+        PFNGLGETPROGRAMINFOLOGPROC        GetProgramInfoLog;
+        PFNGLGETPROGRAMIVPROC             GetProgramiv;
+        PFNGLGETSHADERINFOLOGPROC         GetShaderInfoLog;
+        PFNGLGETSHADERIVPROC              GetShaderiv;
+        PFNGLGETSTRINGPROC                GetString;
+        PFNGLGETSTRINGIPROC               GetStringi;
+        PFNGLGETUNIFORMLOCATIONPROC       GetUniformLocation;
+        PFNGLGETVERTEXATTRIBPOINTERVPROC  GetVertexAttribPointerv;
+        PFNGLGETVERTEXATTRIBIVPROC        GetVertexAttribiv;
+        PFNGLISENABLEDPROC                IsEnabled;
+        PFNGLISPROGRAMPROC                IsProgram;
+        PFNGLLINKPROGRAMPROC              LinkProgram;
+        PFNGLPIXELSTOREIPROC              PixelStorei;
+        PFNGLPOLYGONMODEPROC              PolygonMode;
+        PFNGLREADPIXELSPROC               ReadPixels;
+        PFNGLSCISSORPROC                  Scissor;
+        PFNGLSHADERSOURCEPROC             ShaderSource;
+        PFNGLTEXIMAGE2DPROC               TexImage2D;
+        PFNGLTEXPARAMETERIPROC            TexParameteri;
+        PFNGLUNIFORM1IPROC                Uniform1i;
+        PFNGLUNIFORMMATRIX4FVPROC         UniformMatrix4fv;
+        PFNGLUSEPROGRAMPROC               UseProgram;
+        PFNGLVERTEXATTRIBPOINTERPROC      VertexAttribPointer;
+        PFNGLVIEWPORTPROC                 Viewport;
+    } gl;
+};
+
+GL3W_API extern union GL3WProcs imgl3wProcs;
+
+/* OpenGL functions */
+#define glActiveTexture                   imgl3wProcs.gl.ActiveTexture
+#define glAttachShader                    imgl3wProcs.gl.AttachShader
+#define glBindBuffer                      imgl3wProcs.gl.BindBuffer
+#define glBindSampler                     imgl3wProcs.gl.BindSampler
+#define glBindTexture                     imgl3wProcs.gl.BindTexture
+#define glBindVertexArray                 imgl3wProcs.gl.BindVertexArray
+#define glBlendEquation                   imgl3wProcs.gl.BlendEquation
+#define glBlendEquationSeparate           imgl3wProcs.gl.BlendEquationSeparate
+#define glBlendFuncSeparate               imgl3wProcs.gl.BlendFuncSeparate
+#define glBufferData                      imgl3wProcs.gl.BufferData
+#define glBufferSubData                   imgl3wProcs.gl.BufferSubData
+#define glClear                           imgl3wProcs.gl.Clear
+#define glClearColor                      imgl3wProcs.gl.ClearColor
+#define glCompileShader                   imgl3wProcs.gl.CompileShader
+#define glCreateProgram                   imgl3wProcs.gl.CreateProgram
+#define glCreateShader                    imgl3wProcs.gl.CreateShader
+#define glDeleteBuffers                   imgl3wProcs.gl.DeleteBuffers
+#define glDeleteProgram                   imgl3wProcs.gl.DeleteProgram
+#define glDeleteShader                    imgl3wProcs.gl.DeleteShader
+#define glDeleteTextures                  imgl3wProcs.gl.DeleteTextures
+#define glDeleteVertexArrays              imgl3wProcs.gl.DeleteVertexArrays
+#define glDetachShader                    imgl3wProcs.gl.DetachShader
+#define glDisable                         imgl3wProcs.gl.Disable
+#define glDisableVertexAttribArray        imgl3wProcs.gl.DisableVertexAttribArray
+#define glDrawElements                    imgl3wProcs.gl.DrawElements
+#define glDrawElementsBaseVertex          imgl3wProcs.gl.DrawElementsBaseVertex
+#define glEnable                          imgl3wProcs.gl.Enable
+#define glEnableVertexAttribArray         imgl3wProcs.gl.EnableVertexAttribArray
+#define glFlush                           imgl3wProcs.gl.Flush
+#define glGenBuffers                      imgl3wProcs.gl.GenBuffers
+#define glGenTextures                     imgl3wProcs.gl.GenTextures
+#define glGenVertexArrays                 imgl3wProcs.gl.GenVertexArrays
+#define glGetAttribLocation               imgl3wProcs.gl.GetAttribLocation
+#define glGetError                        imgl3wProcs.gl.GetError
+#define glGetIntegerv                     imgl3wProcs.gl.GetIntegerv
+#define glGetProgramInfoLog               imgl3wProcs.gl.GetProgramInfoLog
+#define glGetProgramiv                    imgl3wProcs.gl.GetProgramiv
+#define glGetShaderInfoLog                imgl3wProcs.gl.GetShaderInfoLog
+#define glGetShaderiv                     imgl3wProcs.gl.GetShaderiv
+#define glGetString                       imgl3wProcs.gl.GetString
+#define glGetStringi                      imgl3wProcs.gl.GetStringi
+#define glGetUniformLocation              imgl3wProcs.gl.GetUniformLocation
+#define glGetVertexAttribPointerv         imgl3wProcs.gl.GetVertexAttribPointerv
+#define glGetVertexAttribiv               imgl3wProcs.gl.GetVertexAttribiv
+#define glIsEnabled                       imgl3wProcs.gl.IsEnabled
+#define glIsProgram                       imgl3wProcs.gl.IsProgram
+#define glLinkProgram                     imgl3wProcs.gl.LinkProgram
+#define glPixelStorei                     imgl3wProcs.gl.PixelStorei
+#define glPolygonMode                     imgl3wProcs.gl.PolygonMode
+#define glReadPixels                      imgl3wProcs.gl.ReadPixels
+#define glScissor                         imgl3wProcs.gl.Scissor
+#define glShaderSource                    imgl3wProcs.gl.ShaderSource
+#define glTexImage2D                      imgl3wProcs.gl.TexImage2D
+#define glTexParameteri                   imgl3wProcs.gl.TexParameteri
+#define glUniform1i                       imgl3wProcs.gl.Uniform1i
+#define glUniformMatrix4fv                imgl3wProcs.gl.UniformMatrix4fv
+#define glUseProgram                      imgl3wProcs.gl.UseProgram
+#define glVertexAttribPointer             imgl3wProcs.gl.VertexAttribPointer
+#define glViewport                        imgl3wProcs.gl.Viewport
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+#ifdef IMGL3W_IMPL
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdlib.h>
+
+#define ARRAY_SIZE(x)  (sizeof(x) / sizeof((x)[0]))
+
+#if defined(_WIN32)
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN 1
+#endif
+#include <windows.h>
+
+static HMODULE libgl;
+typedef PROC(__stdcall* GL3WglGetProcAddr)(LPCSTR);
+static GL3WglGetProcAddr wgl_get_proc_address;
+
+static int open_libgl(void)
+{
+    libgl = LoadLibraryA("opengl32.dll");
+    if (!libgl)
+        return GL3W_ERROR_LIBRARY_OPEN;
+    wgl_get_proc_address = (GL3WglGetProcAddr)GetProcAddress(libgl, "wglGetProcAddress");
+    return GL3W_OK;
+}
+
+static void close_libgl(void) { FreeLibrary(libgl); }
+static GL3WglProc get_proc(const char *proc)
+{
+    GL3WglProc res;
+    res = (GL3WglProc)wgl_get_proc_address(proc);
+    if (!res)
+        res = (GL3WglProc)GetProcAddress(libgl, proc);
+    return res;
+}
+#elif defined(__APPLE__)
+#include <dlfcn.h>
+
+static void *libgl;
+static int open_libgl(void)
+{
+    libgl = dlopen("/System/Library/Frameworks/OpenGL.framework/OpenGL", RTLD_LAZY | RTLD_LOCAL);
+    if (!libgl)
+        return GL3W_ERROR_LIBRARY_OPEN;
+    return GL3W_OK;
+}
+
+static void close_libgl(void) { dlclose(libgl); }
+
+static GL3WglProc get_proc(const char *proc)
+{
+    GL3WglProc res;
+    *(void **)(&res) = dlsym(libgl, proc);
+    return res;
+}
+#else
+#include <dlfcn.h>
+
+static void *libgl;
+static GL3WglProc (*glx_get_proc_address)(const GLubyte *);
+
+static int open_libgl(void)
+{
+    libgl = dlopen("libGL.so.1", RTLD_LAZY | RTLD_LOCAL);
+    if (!libgl)
+        return GL3W_ERROR_LIBRARY_OPEN;
+    *(void **)(&glx_get_proc_address) = dlsym(libgl, "glXGetProcAddressARB");
+    return GL3W_OK;
+}
+
+static void close_libgl(void) { dlclose(libgl); }
+
+static GL3WglProc get_proc(const char *proc)
+{
+    GL3WglProc res;
+    res = glx_get_proc_address((const GLubyte *)proc);
+    if (!res)
+        *(void **)(&res) = dlsym(libgl, proc);
+    return res;
+}
+#endif
+
+static struct { int major, minor; } version;
+
+static int parse_version(void)
+{
+    if (!glGetIntegerv)
+        return GL3W_ERROR_INIT;
+    glGetIntegerv(GL_MAJOR_VERSION, &version.major);
+    glGetIntegerv(GL_MINOR_VERSION, &version.minor);
+    if (version.major == 0 && version.minor == 0)
+    {
+        // Query GL_VERSION in desktop GL 2.x, the string will start with "<major>.<minor>"
+        if (const char* gl_version = (const char*)glGetString(GL_VERSION))
+            sscanf(gl_version, "%d.%d", &version.major, &version.minor);
+    }
+    if (version.major < 2)
+        return GL3W_ERROR_OPENGL_VERSION;
+    return GL3W_OK;
+}
+
+static void load_procs(GL3WGetProcAddressProc proc);
+
+int imgl3wInit(void)
+{
+    int res = open_libgl();
+    if (res)
+        return res;
+    atexit(close_libgl);
+    return imgl3wInit2(get_proc);
+}
+
+int imgl3wInit2(GL3WGetProcAddressProc proc)
+{
+    load_procs(proc);
+    return parse_version();
+}
+
+int imgl3wIsSupported(int major, int minor)
+{
+    if (major < 2)
+        return 0;
+    if (version.major == major)
+        return version.minor >= minor;
+    return version.major >= major;
+}
+
+GL3WglProc imgl3wGetProcAddress(const char *proc) { return get_proc(proc); }
+
+static const char *proc_names[] = {
+    "glActiveTexture",
+    "glAttachShader",
+    "glBindBuffer",
+    "glBindSampler",
+    "glBindTexture",
+    "glBindVertexArray",
+    "glBlendEquation",
+    "glBlendEquationSeparate",
+    "glBlendFuncSeparate",
+    "glBufferData",
+    "glBufferSubData",
+    "glClear",
+    "glClearColor",
+    "glCompileShader",
+    "glCreateProgram",
+    "glCreateShader",
+    "glDeleteBuffers",
+    "glDeleteProgram",
+    "glDeleteShader",
+    "glDeleteTextures",
+    "glDeleteVertexArrays",
+    "glDetachShader",
+    "glDisable",
+    "glDisableVertexAttribArray",
+    "glDrawElements",
+    "glDrawElementsBaseVertex",
+    "glEnable",
+    "glEnableVertexAttribArray",
+    "glFlush",
+    "glGenBuffers",
+    "glGenTextures",
+    "glGenVertexArrays",
+    "glGetAttribLocation",
+    "glGetError",
+    "glGetIntegerv",
+    "glGetProgramInfoLog",
+    "glGetProgramiv",
+    "glGetShaderInfoLog",
+    "glGetShaderiv",
+    "glGetString",
+    "glGetStringi",
+    "glGetUniformLocation",
+    "glGetVertexAttribPointerv",
+    "glGetVertexAttribiv",
+    "glIsEnabled",
+    "glIsProgram",
+    "glLinkProgram",
+    "glPixelStorei",
+    "glPolygonMode",
+    "glReadPixels",
+    "glScissor",
+    "glShaderSource",
+    "glTexImage2D",
+    "glTexParameteri",
+    "glUniform1i",
+    "glUniformMatrix4fv",
+    "glUseProgram",
+    "glVertexAttribPointer",
+    "glViewport",
+};
+
+GL3W_API union GL3WProcs imgl3wProcs;
+
+static void load_procs(GL3WGetProcAddressProc proc)
+{
+    size_t i;
+    for (i = 0; i < ARRAY_SIZE(proc_names); i++)
+        imgl3wProcs.ptr[i] = proc(proc_names[i]);
+}
+
+#ifdef __cplusplus
+}
+#endif
+#endif

ext/imgui/backends/imgui_impl_osx.h

@@ -0,0 +1,51 @@
+// dear imgui: Platform Backend for OSX / Cocoa
+// This needs to be used along with a Renderer (e.g. OpenGL2, OpenGL3, Vulkan, Metal..)
+// - Not well tested. If you want a portable application, prefer using the GLFW or SDL platform Backends on Mac.
+// - Requires linking with the GameController framework ("-framework GameController").
+
+// Implemented features:
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse support. Can discriminate Mouse/Pen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: OSX clipboard is supported within core Dear ImGui (no specific code in this backend).
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: IME support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+#ifdef __OBJC__
+
+@class NSEvent;
+@class NSView;
+
+IMGUI_IMPL_API bool     ImGui_ImplOSX_Init(NSView* _Nonnull view);
+IMGUI_IMPL_API void     ImGui_ImplOSX_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOSX_NewFrame(NSView* _Nullable view);
+
+#endif
+
+//-----------------------------------------------------------------------------
+// C++ API
+//-----------------------------------------------------------------------------
+
+#ifdef IMGUI_IMPL_METAL_CPP_EXTENSIONS
+// #include <AppKit/AppKit.hpp>
+#ifndef __OBJC__
+
+IMGUI_IMPL_API bool     ImGui_ImplOSX_Init(void* _Nonnull view);
+IMGUI_IMPL_API void     ImGui_ImplOSX_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOSX_NewFrame(void* _Nullable view);
+
+#endif
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_osx.mm

@@ -0,0 +1,811 @@
+// dear imgui: Platform Backend for OSX / Cocoa
+// This needs to be used along with a Renderer (e.g. OpenGL2, OpenGL3, Vulkan, Metal..)
+// - Not well tested. If you want a portable application, prefer using the GLFW or SDL platform Backends on Mac.
+// - Requires linking with the GameController framework ("-framework GameController").
+
+// Implemented features:
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse support. Can discriminate Mouse/Pen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: OSX clipboard is supported within core Dear ImGui (no specific code in this backend).
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: IME support.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#import "imgui.h"
+#ifndef IMGUI_DISABLE
+#import "imgui_impl_osx.h"
+#import <Cocoa/Cocoa.h>
+#import <Carbon/Carbon.h>
+#import <GameController/GameController.h>
+#import <time.h>
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-04-09: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_Pen.
+//  2023-02-01: Fixed scroll wheel scaling for devices emitting events with hasPreciseScrollingDeltas==false (e.g. non-Apple mices).
+//  2022-11-02: Fixed mouse coordinates before clicking the host window.
+//  2022-10-06: Fixed mouse inputs on flipped views.
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-05-03: Inputs: Removed ImGui_ImplOSX_HandleEvent() from backend API in favor of backend automatically handling event capture.
+//  2022-04-27: Misc: Store backend data in a per-context struct, allowing to use this backend with multiple contexts.
+//  2022-03-22: Inputs: Monitor NSKeyUp events to catch missing keyUp for key when user press Cmd + key
+//  2022-02-07: Inputs: Forward keyDown/keyUp events to OS when unused by dear imgui.
+//  2022-01-31: Fixed building with old Xcode versions that are missing gamepad features.
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2021-01-20: Inputs: calling new io.AddKeyAnalogEvent() for gamepad support, instead of writing directly to io.NavInputs[].
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-12: Inputs: Added basic Platform IME support, hooking the io.SetPlatformImeDataFn() function.
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-12-13: *BREAKING CHANGE* Add NSView parameter to ImGui_ImplOSX_Init(). Generally fix keyboard support. Using kVK_* codes for keyboard keys.
+//  2021-12-13: Add game controller support.
+//  2021-09-21: Use mach_absolute_time as CFAbsoluteTimeGetCurrent can jump backwards.
+//  2021-08-17: Calling io.AddFocusEvent() on NSApplicationDidBecomeActiveNotification/NSApplicationDidResignActiveNotification events.
+//  2021-06-23: Inputs: Added a fix for shortcuts using CTRL key instead of CMD key.
+//  2021-04-19: Inputs: Added a fix for keys remaining stuck in pressed state when CMD-tabbing into different application.
+//  2021-01-27: Inputs: Added a fix for mouse position not being reported when mouse buttons other than left one are down.
+//  2020-10-28: Inputs: Added a fix for handling keypad-enter key.
+//  2020-05-25: Inputs: Added a fix for missing trackpad clicks when done with "soft tap".
+//  2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
+//  2019-10-11: Inputs:  Fix using Backspace key.
+//  2019-07-21: Re-added clipboard handlers as they are not enabled by default in core imgui.cpp (reverted 2019-05-18 change).
+//  2019-05-28: Inputs: Added mouse cursor shape and visibility support.
+//  2019-05-18: Misc: Removed clipboard handlers as they are now supported by core imgui.cpp.
+//  2019-05-11: Inputs: Don't filter character values before calling AddInputCharacter() apart from 0xF700..0xFFFF range.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-07-07: Initial version.
+
+#define APPLE_HAS_BUTTON_OPTIONS (__IPHONE_OS_VERSION_MIN_REQUIRED >= 130000 || __MAC_OS_X_VERSION_MIN_REQUIRED >= 101500 || __TV_OS_VERSION_MIN_REQUIRED >= 130000)
+#define APPLE_HAS_CONTROLLER     (__IPHONE_OS_VERSION_MIN_REQUIRED >= 140000 || __MAC_OS_X_VERSION_MIN_REQUIRED >= 110000 || __TV_OS_VERSION_MIN_REQUIRED >= 140000)
+#define APPLE_HAS_THUMBSTICKS    (__IPHONE_OS_VERSION_MIN_REQUIRED >= 120100 || __MAC_OS_X_VERSION_MIN_REQUIRED >= 101401 || __TV_OS_VERSION_MIN_REQUIRED >= 120100)
+
+@class ImGuiObserver;
+@class KeyEventResponder;
+
+// Data
+struct ImGui_ImplOSX_Data
+{
+    CFTimeInterval              Time;
+    NSCursor*                   MouseCursors[ImGuiMouseCursor_COUNT];
+    bool                        MouseCursorHidden;
+    ImGuiObserver*              Observer;
+    KeyEventResponder*          KeyEventResponder;
+    NSTextInputContext*         InputContext;
+    id                          Monitor;
+
+    ImGui_ImplOSX_Data()        { memset(this, 0, sizeof(*this)); }
+};
+
+static ImGui_ImplOSX_Data*      ImGui_ImplOSX_CreateBackendData()   { return IM_NEW(ImGui_ImplOSX_Data)(); }
+static ImGui_ImplOSX_Data*      ImGui_ImplOSX_GetBackendData()      { return (ImGui_ImplOSX_Data*)ImGui::GetIO().BackendPlatformUserData; }
+static void                     ImGui_ImplOSX_DestroyBackendData()  { IM_DELETE(ImGui_ImplOSX_GetBackendData()); }
+
+static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
+
+// Forward Declarations
+static void ImGui_ImplOSX_AddTrackingArea(NSView* _Nonnull view);
+static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view);
+
+// Undocumented methods for creating cursors.
+@interface NSCursor()
++ (id)_windowResizeNorthWestSouthEastCursor;
++ (id)_windowResizeNorthEastSouthWestCursor;
++ (id)_windowResizeNorthSouthCursor;
++ (id)_windowResizeEastWestCursor;
+@end
+
+/**
+ KeyEventResponder implements the NSTextInputClient protocol as is required by the macOS text input manager.
+
+ The macOS text input manager is invoked by calling the interpretKeyEvents method from the keyDown method.
+ Keyboard events are then evaluated by the macOS input manager and valid text input is passed back via the
+ insertText:replacementRange method.
+
+ This is the same approach employed by other cross-platform libraries such as SDL2:
+  https://github.com/spurious/SDL-mirror/blob/e17aacbd09e65a4fd1e166621e011e581fb017a8/src/video/cocoa/SDL_cocoakeyboard.m#L53
+ and GLFW:
+  https://github.com/glfw/glfw/blob/b55a517ae0c7b5127dffa79a64f5406021bf9076/src/cocoa_window.m#L722-L723
+ */
+@interface KeyEventResponder: NSView<NSTextInputClient>
+@end
+
+@implementation KeyEventResponder
+{
+    float _posX;
+    float _posY;
+    NSRect _imeRect;
+}
+
+#pragma mark - Public
+
+- (void)setImePosX:(float)posX imePosY:(float)posY
+{
+    _posX = posX;
+    _posY = posY;
+}
+
+- (void)updateImePosWithView:(NSView *)view
+{
+    NSWindow *window = view.window;
+    if (!window)
+        return;
+    NSRect contentRect = [window contentRectForFrameRect:window.frame];
+    NSRect rect = NSMakeRect(_posX, contentRect.size.height - _posY, 0, 0);
+    _imeRect = [window convertRectToScreen:rect];
+}
+
+- (void)viewDidMoveToWindow
+{
+    // Ensure self is a first responder to receive the input events.
+    [self.window makeFirstResponder:self];
+}
+
+- (void)keyDown:(NSEvent*)event
+{
+    if (!ImGui_ImplOSX_HandleEvent(event, self))
+        [super keyDown:event];
+
+    // Call to the macOS input manager system.
+    [self interpretKeyEvents:@[event]];
+}
+
+- (void)keyUp:(NSEvent*)event
+{
+    if (!ImGui_ImplOSX_HandleEvent(event, self))
+        [super keyUp:event];
+}
+
+- (void)insertText:(id)aString replacementRange:(NSRange)replacementRange
+{
+    ImGuiIO& io = ImGui::GetIO();
+
+    NSString* characters;
+    if ([aString isKindOfClass:[NSAttributedString class]])
+        characters = [aString string];
+    else
+        characters = (NSString*)aString;
+
+    io.AddInputCharactersUTF8(characters.UTF8String);
+}
+
+- (BOOL)acceptsFirstResponder
+{
+    return YES;
+}
+
+- (void)doCommandBySelector:(SEL)myselector
+{
+}
+
+- (nullable NSAttributedString*)attributedSubstringForProposedRange:(NSRange)range actualRange:(nullable NSRangePointer)actualRange
+{
+    return nil;
+}
+
+- (NSUInteger)characterIndexForPoint:(NSPoint)point
+{
+    return 0;
+}
+
+- (NSRect)firstRectForCharacterRange:(NSRange)range actualRange:(nullable NSRangePointer)actualRange
+{
+    return _imeRect;
+}
+
+- (BOOL)hasMarkedText
+{
+    return NO;
+}
+
+- (NSRange)markedRange
+{
+    return NSMakeRange(NSNotFound, 0);
+}
+
+- (NSRange)selectedRange
+{
+    return NSMakeRange(NSNotFound, 0);
+}
+
+- (void)setMarkedText:(nonnull id)string selectedRange:(NSRange)selectedRange replacementRange:(NSRange)replacementRange
+{
+}
+
+- (void)unmarkText
+{
+}
+
+- (nonnull NSArray<NSAttributedStringKey>*)validAttributesForMarkedText
+{
+    return @[];
+}
+
+@end
+
+@interface ImGuiObserver : NSObject
+
+- (void)onApplicationBecomeActive:(NSNotification*)aNotification;
+- (void)onApplicationBecomeInactive:(NSNotification*)aNotification;
+
+@end
+
+@implementation ImGuiObserver
+
+- (void)onApplicationBecomeActive:(NSNotification*)aNotification
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddFocusEvent(true);
+}
+
+- (void)onApplicationBecomeInactive:(NSNotification*)aNotification
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddFocusEvent(false);
+}
+
+@end
+
+// Functions
+static ImGuiKey ImGui_ImplOSX_KeyCodeToImGuiKey(int key_code)
+{
+    switch (key_code)
+    {
+        case kVK_ANSI_A: return ImGuiKey_A;
+        case kVK_ANSI_S: return ImGuiKey_S;
+        case kVK_ANSI_D: return ImGuiKey_D;
+        case kVK_ANSI_F: return ImGuiKey_F;
+        case kVK_ANSI_H: return ImGuiKey_H;
+        case kVK_ANSI_G: return ImGuiKey_G;
+        case kVK_ANSI_Z: return ImGuiKey_Z;
+        case kVK_ANSI_X: return ImGuiKey_X;
+        case kVK_ANSI_C: return ImGuiKey_C;
+        case kVK_ANSI_V: return ImGuiKey_V;
+        case kVK_ANSI_B: return ImGuiKey_B;
+        case kVK_ANSI_Q: return ImGuiKey_Q;
+        case kVK_ANSI_W: return ImGuiKey_W;
+        case kVK_ANSI_E: return ImGuiKey_E;
+        case kVK_ANSI_R: return ImGuiKey_R;
+        case kVK_ANSI_Y: return ImGuiKey_Y;
+        case kVK_ANSI_T: return ImGuiKey_T;
+        case kVK_ANSI_1: return ImGuiKey_1;
+        case kVK_ANSI_2: return ImGuiKey_2;
+        case kVK_ANSI_3: return ImGuiKey_3;
+        case kVK_ANSI_4: return ImGuiKey_4;
+        case kVK_ANSI_6: return ImGuiKey_6;
+        case kVK_ANSI_5: return ImGuiKey_5;
+        case kVK_ANSI_Equal: return ImGuiKey_Equal;
+        case kVK_ANSI_9: return ImGuiKey_9;
+        case kVK_ANSI_7: return ImGuiKey_7;
+        case kVK_ANSI_Minus: return ImGuiKey_Minus;
+        case kVK_ANSI_8: return ImGuiKey_8;
+        case kVK_ANSI_0: return ImGuiKey_0;
+        case kVK_ANSI_RightBracket: return ImGuiKey_RightBracket;
+        case kVK_ANSI_O: return ImGuiKey_O;
+        case kVK_ANSI_U: return ImGuiKey_U;
+        case kVK_ANSI_LeftBracket: return ImGuiKey_LeftBracket;
+        case kVK_ANSI_I: return ImGuiKey_I;
+        case kVK_ANSI_P: return ImGuiKey_P;
+        case kVK_ANSI_L: return ImGuiKey_L;
+        case kVK_ANSI_J: return ImGuiKey_J;
+        case kVK_ANSI_Quote: return ImGuiKey_Apostrophe;
+        case kVK_ANSI_K: return ImGuiKey_K;
+        case kVK_ANSI_Semicolon: return ImGuiKey_Semicolon;
+        case kVK_ANSI_Backslash: return ImGuiKey_Backslash;
+        case kVK_ANSI_Comma: return ImGuiKey_Comma;
+        case kVK_ANSI_Slash: return ImGuiKey_Slash;
+        case kVK_ANSI_N: return ImGuiKey_N;
+        case kVK_ANSI_M: return ImGuiKey_M;
+        case kVK_ANSI_Period: return ImGuiKey_Period;
+        case kVK_ANSI_Grave: return ImGuiKey_GraveAccent;
+        case kVK_ANSI_KeypadDecimal: return ImGuiKey_KeypadDecimal;
+        case kVK_ANSI_KeypadMultiply: return ImGuiKey_KeypadMultiply;
+        case kVK_ANSI_KeypadPlus: return ImGuiKey_KeypadAdd;
+        case kVK_ANSI_KeypadClear: return ImGuiKey_NumLock;
+        case kVK_ANSI_KeypadDivide: return ImGuiKey_KeypadDivide;
+        case kVK_ANSI_KeypadEnter: return ImGuiKey_KeypadEnter;
+        case kVK_ANSI_KeypadMinus: return ImGuiKey_KeypadSubtract;
+        case kVK_ANSI_KeypadEquals: return ImGuiKey_KeypadEqual;
+        case kVK_ANSI_Keypad0: return ImGuiKey_Keypad0;
+        case kVK_ANSI_Keypad1: return ImGuiKey_Keypad1;
+        case kVK_ANSI_Keypad2: return ImGuiKey_Keypad2;
+        case kVK_ANSI_Keypad3: return ImGuiKey_Keypad3;
+        case kVK_ANSI_Keypad4: return ImGuiKey_Keypad4;
+        case kVK_ANSI_Keypad5: return ImGuiKey_Keypad5;
+        case kVK_ANSI_Keypad6: return ImGuiKey_Keypad6;
+        case kVK_ANSI_Keypad7: return ImGuiKey_Keypad7;
+        case kVK_ANSI_Keypad8: return ImGuiKey_Keypad8;
+        case kVK_ANSI_Keypad9: return ImGuiKey_Keypad9;
+        case kVK_Return: return ImGuiKey_Enter;
+        case kVK_Tab: return ImGuiKey_Tab;
+        case kVK_Space: return ImGuiKey_Space;
+        case kVK_Delete: return ImGuiKey_Backspace;
+        case kVK_Escape: return ImGuiKey_Escape;
+        case kVK_CapsLock: return ImGuiKey_CapsLock;
+        case kVK_Control: return ImGuiKey_LeftCtrl;
+        case kVK_Shift: return ImGuiKey_LeftShift;
+        case kVK_Option: return ImGuiKey_LeftAlt;
+        case kVK_Command: return ImGuiKey_LeftSuper;
+        case kVK_RightControl: return ImGuiKey_RightCtrl;
+        case kVK_RightShift: return ImGuiKey_RightShift;
+        case kVK_RightOption: return ImGuiKey_RightAlt;
+        case kVK_RightCommand: return ImGuiKey_RightSuper;
+//      case kVK_Function: return ImGuiKey_;
+//      case kVK_F17: return ImGuiKey_;
+//      case kVK_VolumeUp: return ImGuiKey_;
+//      case kVK_VolumeDown: return ImGuiKey_;
+//      case kVK_Mute: return ImGuiKey_;
+//      case kVK_F18: return ImGuiKey_;
+//      case kVK_F19: return ImGuiKey_;
+//      case kVK_F20: return ImGuiKey_;
+        case kVK_F5: return ImGuiKey_F5;
+        case kVK_F6: return ImGuiKey_F6;
+        case kVK_F7: return ImGuiKey_F7;
+        case kVK_F3: return ImGuiKey_F3;
+        case kVK_F8: return ImGuiKey_F8;
+        case kVK_F9: return ImGuiKey_F9;
+        case kVK_F11: return ImGuiKey_F11;
+        case kVK_F13: return ImGuiKey_PrintScreen;
+//      case kVK_F16: return ImGuiKey_;
+//      case kVK_F14: return ImGuiKey_;
+        case kVK_F10: return ImGuiKey_F10;
+        case 0x6E: return ImGuiKey_Menu;
+        case kVK_F12: return ImGuiKey_F12;
+//      case kVK_F15: return ImGuiKey_;
+        case kVK_Help: return ImGuiKey_Insert;
+        case kVK_Home: return ImGuiKey_Home;
+        case kVK_PageUp: return ImGuiKey_PageUp;
+        case kVK_ForwardDelete: return ImGuiKey_Delete;
+        case kVK_F4: return ImGuiKey_F4;
+        case kVK_End: return ImGuiKey_End;
+        case kVK_F2: return ImGuiKey_F2;
+        case kVK_PageDown: return ImGuiKey_PageDown;
+        case kVK_F1: return ImGuiKey_F1;
+        case kVK_LeftArrow: return ImGuiKey_LeftArrow;
+        case kVK_RightArrow: return ImGuiKey_RightArrow;
+        case kVK_DownArrow: return ImGuiKey_DownArrow;
+        case kVK_UpArrow: return ImGuiKey_UpArrow;
+        default: return ImGuiKey_None;
+    }
+}
+
+#ifdef IMGUI_IMPL_METAL_CPP_EXTENSIONS
+
+IMGUI_IMPL_API bool ImGui_ImplOSX_Init(void* _Nonnull view) {
+    return ImGui_ImplOSX_Init((__bridge NSView*)(view));
+}
+
+IMGUI_IMPL_API void ImGui_ImplOSX_NewFrame(void* _Nullable view) {
+    return ImGui_ImplOSX_NewFrame((__bridge NSView*)(view));
+}
+
+#endif
+
+
+bool ImGui_ImplOSX_Init(NSView* view)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_CreateBackendData();
+    io.BackendPlatformUserData = (void*)bd;
+
+    // Setup backend capabilities flags
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
+    //io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+    io.BackendPlatformName = "imgui_impl_osx";
+
+    bd->Observer = [ImGuiObserver new];
+
+    // Load cursors. Some of them are undocumented.
+    bd->MouseCursorHidden = false;
+    bd->MouseCursors[ImGuiMouseCursor_Arrow] = [NSCursor arrowCursor];
+    bd->MouseCursors[ImGuiMouseCursor_TextInput] = [NSCursor IBeamCursor];
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = [NSCursor closedHandCursor];
+    bd->MouseCursors[ImGuiMouseCursor_Hand] = [NSCursor pointingHandCursor];
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = [NSCursor operationNotAllowedCursor];
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNS] = [NSCursor respondsToSelector:@selector(_windowResizeNorthSouthCursor)] ? [NSCursor _windowResizeNorthSouthCursor] : [NSCursor resizeUpDownCursor];
+    bd->MouseCursors[ImGuiMouseCursor_ResizeEW] = [NSCursor respondsToSelector:@selector(_windowResizeEastWestCursor)] ? [NSCursor _windowResizeEastWestCursor] : [NSCursor resizeLeftRightCursor];
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = [NSCursor respondsToSelector:@selector(_windowResizeNorthEastSouthWestCursor)] ? [NSCursor _windowResizeNorthEastSouthWestCursor] : [NSCursor closedHandCursor];
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = [NSCursor respondsToSelector:@selector(_windowResizeNorthWestSouthEastCursor)] ? [NSCursor _windowResizeNorthWestSouthEastCursor] : [NSCursor closedHandCursor];
+
+    // Note that imgui.cpp also include default OSX clipboard handlers which can be enabled
+    // by adding '#define IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS' in imconfig.h and adding '-framework ApplicationServices' to your linker command-line.
+    // Since we are already in ObjC land here, it is easy for us to add a clipboard handler using the NSPasteboard api.
+    io.SetClipboardTextFn = [](void*, const char* str) -> void
+    {
+        NSPasteboard* pasteboard = [NSPasteboard generalPasteboard];
+        [pasteboard declareTypes:[NSArray arrayWithObject:NSPasteboardTypeString] owner:nil];
+        [pasteboard setString:[NSString stringWithUTF8String:str] forType:NSPasteboardTypeString];
+    };
+
+    io.GetClipboardTextFn = [](void*) -> const char*
+    {
+        NSPasteboard* pasteboard = [NSPasteboard generalPasteboard];
+        NSString* available = [pasteboard availableTypeFromArray: [NSArray arrayWithObject:NSPasteboardTypeString]];
+        if (![available isEqualToString:NSPasteboardTypeString])
+            return nullptr;
+
+        NSString* string = [pasteboard stringForType:NSPasteboardTypeString];
+        if (string == nil)
+            return nullptr;
+
+        const char* string_c = (const char*)[string UTF8String];
+        size_t string_len = strlen(string_c);
+        static ImVector<char> s_clipboard;
+        s_clipboard.resize((int)string_len + 1);
+        strcpy(s_clipboard.Data, string_c);
+        return s_clipboard.Data;
+    };
+
+    [[NSNotificationCenter defaultCenter] addObserver:bd->Observer
+                                             selector:@selector(onApplicationBecomeActive:)
+                                                 name:NSApplicationDidBecomeActiveNotification
+                                               object:nil];
+    [[NSNotificationCenter defaultCenter] addObserver:bd->Observer
+                                             selector:@selector(onApplicationBecomeInactive:)
+                                                 name:NSApplicationDidResignActiveNotification
+                                               object:nil];
+
+    // Add the NSTextInputClient to the view hierarchy,
+    // to receive keyboard events and translate them to input text.
+    bd->KeyEventResponder = [[KeyEventResponder alloc] initWithFrame:NSZeroRect];
+    bd->InputContext = [[NSTextInputContext alloc] initWithClient:bd->KeyEventResponder];
+    [view addSubview:bd->KeyEventResponder];
+    ImGui_ImplOSX_AddTrackingArea(view);
+
+    io.SetPlatformImeDataFn = [](ImGuiViewport* viewport, ImGuiPlatformImeData* data) -> void
+    {
+        ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+        if (data->WantVisible)
+        {
+            [bd->InputContext activate];
+        }
+        else
+        {
+            [bd->InputContext discardMarkedText];
+            [bd->InputContext invalidateCharacterCoordinates];
+            [bd->InputContext deactivate];
+        }
+        [bd->KeyEventResponder setImePosX:data->InputPos.x imePosY:data->InputPos.y + data->InputLineHeight];
+    };
+
+    return true;
+}
+
+void ImGui_ImplOSX_Shutdown()
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+
+    bd->Observer = nullptr;
+    if (bd->Monitor != nullptr)
+    {
+        [NSEvent removeMonitor:bd->Monitor];
+        bd->Monitor = nullptr;
+    }
+
+    ImGui_ImplOSX_DestroyBackendData();
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasGamepad);
+}
+
+static void ImGui_ImplOSX_UpdateMouseCursor()
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return;
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        if (!bd->MouseCursorHidden)
+        {
+            bd->MouseCursorHidden = true;
+            [NSCursor hide];
+        }
+    }
+    else
+    {
+        NSCursor* desired = bd->MouseCursors[imgui_cursor] ?: bd->MouseCursors[ImGuiMouseCursor_Arrow];
+        // -[NSCursor set] generates measureable overhead if called unconditionally.
+        if (desired != NSCursor.currentCursor)
+        {
+            [desired set];
+        }
+        if (bd->MouseCursorHidden)
+        {
+            bd->MouseCursorHidden = false;
+            [NSCursor unhide];
+        }
+    }
+}
+
+static void ImGui_ImplOSX_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    memset(io.NavInputs, 0, sizeof(io.NavInputs));
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+        return;
+
+#if APPLE_HAS_CONTROLLER
+    GCController* controller = GCController.current;
+#else
+    GCController* controller = GCController.controllers.firstObject;
+#endif
+    if (controller == nil || controller.extendedGamepad == nil)
+    {
+        io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+        return;
+    }
+
+    GCExtendedGamepad* gp = controller.extendedGamepad;
+
+    // Update gamepad inputs
+    #define IM_SATURATE(V)                        (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V)
+    #define MAP_BUTTON(KEY_NO, BUTTON_NAME)       { io.AddKeyEvent(KEY_NO, gp.BUTTON_NAME.isPressed); }
+    #define MAP_ANALOG(KEY_NO, AXIS_NAME, V0, V1) { float vn = (float)(gp.AXIS_NAME.value - V0) / (float)(V1 - V0); vn = IM_SATURATE(vn); io.AddKeyAnalogEvent(KEY_NO, vn > 0.1f, vn); }
+    const float thumb_dead_zone = 0.0f;
+
+#if APPLE_HAS_BUTTON_OPTIONS
+    MAP_BUTTON(ImGuiKey_GamepadBack,            buttonOptions);
+#endif
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,        buttonX);              // Xbox X, PS Square
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,       buttonB);              // Xbox B, PS Circle
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,          buttonY);              // Xbox Y, PS Triangle
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,        buttonA);              // Xbox A, PS Cross
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,        dpad.left);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,       dpad.right);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,          dpad.up);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,        dpad.down);
+    MAP_ANALOG(ImGuiKey_GamepadL1,              leftShoulder, 0.0f, 1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadR1,              rightShoulder, 0.0f, 1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadL2,              leftTrigger,  0.0f, 1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadR2,              rightTrigger, 0.0f, 1.0f);
+#if APPLE_HAS_THUMBSTICKS
+    MAP_BUTTON(ImGuiKey_GamepadL3,              leftThumbstickButton);
+    MAP_BUTTON(ImGuiKey_GamepadR3,              rightThumbstickButton);
+#endif
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,      leftThumbstick.xAxis,  -thumb_dead_zone, -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight,     leftThumbstick.xAxis,  +thumb_dead_zone, +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,        leftThumbstick.yAxis,  +thumb_dead_zone, +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,      leftThumbstick.yAxis,  -thumb_dead_zone, -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,      rightThumbstick.xAxis, -thumb_dead_zone, -1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight,     rightThumbstick.xAxis, +thumb_dead_zone, +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,        rightThumbstick.yAxis, +thumb_dead_zone, +1.0f);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,      rightThumbstick.yAxis, -thumb_dead_zone, -1.0f);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+}
+
+static void ImGui_ImplOSX_UpdateImePosWithView(NSView* view)
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.WantTextInput)
+        [bd->KeyEventResponder updateImePosWithView:view];
+}
+
+void ImGui_ImplOSX_NewFrame(NSView* view)
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size
+    if (view)
+    {
+        const float dpi = (float)[view.window backingScaleFactor];
+        io.DisplaySize = ImVec2((float)view.bounds.size.width, (float)view.bounds.size.height);
+        io.DisplayFramebufferScale = ImVec2(dpi, dpi);
+    }
+
+    // Setup time step
+    if (bd->Time == 0.0)
+        bd->Time = GetMachAbsoluteTimeInSeconds();
+
+    double current_time = GetMachAbsoluteTimeInSeconds();
+    io.DeltaTime = (float)(current_time - bd->Time);
+    bd->Time = current_time;
+
+    ImGui_ImplOSX_UpdateMouseCursor();
+    ImGui_ImplOSX_UpdateGamepads();
+    ImGui_ImplOSX_UpdateImePosWithView(view);
+}
+
+// Must only be called for a mouse event, otherwise an exception occurs
+// (Note that NSEventTypeScrollWheel is considered "other input". Oddly enough an exception does not occur with it, but the value will sometimes be wrong!)
+static ImGuiMouseSource GetMouseSource(NSEvent* event)
+{
+    switch (event.subtype)
+    {
+        case NSEventSubtypeTabletPoint:
+            return ImGuiMouseSource_Pen;
+        // macOS considers input from relative touch devices (like the trackpad or Apple Magic Mouse) to be touch input.
+        // This doesn't really make sense for Dear ImGui, which expects absolute touch devices only.
+        // There does not seem to be a simple way to disambiguate things here so we consider NSEventSubtypeTouch events to always come from mice.
+        // See https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/EventOverview/HandlingTouchEvents/HandlingTouchEvents.html#//apple_ref/doc/uid/10000060i-CH13-SW24
+        //case NSEventSubtypeTouch:
+        //    return ImGuiMouseSource_TouchScreen;
+        case NSEventSubtypeMouseEvent:
+        default:
+            return ImGuiMouseSource_Mouse;
+    }
+}
+
+static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view)
+{
+    ImGuiIO& io = ImGui::GetIO();
+
+    if (event.type == NSEventTypeLeftMouseDown || event.type == NSEventTypeRightMouseDown || event.type == NSEventTypeOtherMouseDown)
+    {
+        int button = (int)[event buttonNumber];
+        if (button >= 0 && button < ImGuiMouseButton_COUNT)
+        {
+            io.AddMouseSourceEvent(GetMouseSource(event));
+            io.AddMouseButtonEvent(button, true);
+        }
+        return io.WantCaptureMouse;
+    }
+
+    if (event.type == NSEventTypeLeftMouseUp || event.type == NSEventTypeRightMouseUp || event.type == NSEventTypeOtherMouseUp)
+    {
+        int button = (int)[event buttonNumber];
+        if (button >= 0 && button < ImGuiMouseButton_COUNT)
+        {
+            io.AddMouseSourceEvent(GetMouseSource(event));
+            io.AddMouseButtonEvent(button, false);
+        }
+        return io.WantCaptureMouse;
+    }
+
+    if (event.type == NSEventTypeMouseMoved || event.type == NSEventTypeLeftMouseDragged || event.type == NSEventTypeRightMouseDragged || event.type == NSEventTypeOtherMouseDragged)
+    {
+        NSPoint mousePoint = event.locationInWindow;
+        if (event.window == nil)
+            mousePoint = [[view window] convertPointFromScreen:mousePoint];
+        mousePoint = [view convertPoint:mousePoint fromView:nil];
+        if ([view isFlipped])
+            mousePoint = NSMakePoint(mousePoint.x, mousePoint.y);
+        else
+            mousePoint = NSMakePoint(mousePoint.x, view.bounds.size.height - mousePoint.y);
+        io.AddMouseSourceEvent(GetMouseSource(event));
+        io.AddMousePosEvent((float)mousePoint.x, (float)mousePoint.y);
+        return io.WantCaptureMouse;
+    }
+
+    if (event.type == NSEventTypeScrollWheel)
+    {
+        // Ignore canceled events.
+        //
+        // From macOS 12.1, scrolling with two fingers and then decelerating
+        // by tapping two fingers results in two events appearing:
+        //
+        // 1. A scroll wheel NSEvent, with a phase == NSEventPhaseMayBegin, when the user taps
+        // two fingers to decelerate or stop the scroll events.
+        //
+        // 2. A scroll wheel NSEvent, with a phase == NSEventPhaseCancelled, when the user releases the
+        // two-finger tap. It is this event that sometimes contains large values for scrollingDeltaX and
+        // scrollingDeltaY. When these are added to the current x and y positions of the scrolling view,
+        // it appears to jump up or down. It can be observed in Preview, various JetBrains IDEs and here.
+        if (event.phase == NSEventPhaseCancelled)
+            return false;
+
+        double wheel_dx = 0.0;
+        double wheel_dy = 0.0;
+
+        #if MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+        if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_6)
+        {
+            wheel_dx = [event scrollingDeltaX];
+            wheel_dy = [event scrollingDeltaY];
+            if ([event hasPreciseScrollingDeltas])
+            {
+                wheel_dx *= 0.01;
+                wheel_dy *= 0.01;
+            }
+        }
+        else
+        #endif // MAC_OS_X_VERSION_MAX_ALLOWED
+        {
+            wheel_dx = [event deltaX] * 0.1;
+            wheel_dy = [event deltaY] * 0.1;
+        }
+        if (wheel_dx != 0.0 || wheel_dy != 0.0)
+            io.AddMouseWheelEvent((float)wheel_dx, (float)wheel_dy);
+
+        return io.WantCaptureMouse;
+    }
+
+    if (event.type == NSEventTypeKeyDown || event.type == NSEventTypeKeyUp)
+    {
+        if ([event isARepeat])
+            return io.WantCaptureKeyboard;
+
+        int key_code = (int)[event keyCode];
+        ImGuiKey key = ImGui_ImplOSX_KeyCodeToImGuiKey(key_code);
+        io.AddKeyEvent(key, event.type == NSEventTypeKeyDown);
+        io.SetKeyEventNativeData(key, key_code, -1); // To support legacy indexing (<1.87 user code)
+
+        return io.WantCaptureKeyboard;
+    }
+
+    if (event.type == NSEventTypeFlagsChanged)
+    {
+        unsigned short key_code = [event keyCode];
+        NSEventModifierFlags modifier_flags = [event modifierFlags];
+
+        io.AddKeyEvent(ImGuiMod_Shift, (modifier_flags & NSEventModifierFlagShift)   != 0);
+        io.AddKeyEvent(ImGuiMod_Ctrl,  (modifier_flags & NSEventModifierFlagControl) != 0);
+        io.AddKeyEvent(ImGuiMod_Alt,   (modifier_flags & NSEventModifierFlagOption)  != 0);
+        io.AddKeyEvent(ImGuiMod_Super, (modifier_flags & NSEventModifierFlagCommand) != 0);
+
+        ImGuiKey key = ImGui_ImplOSX_KeyCodeToImGuiKey(key_code);
+        if (key != ImGuiKey_None)
+        {
+            // macOS does not generate down/up event for modifiers. We're trying
+            // to use hardware dependent masks to extract that information.
+            // 'imgui_mask' is left as a fallback.
+            NSEventModifierFlags mask = 0;
+            switch (key)
+            {
+                case ImGuiKey_LeftCtrl:   mask = 0x0001; break;
+                case ImGuiKey_RightCtrl:  mask = 0x2000; break;
+                case ImGuiKey_LeftShift:  mask = 0x0002; break;
+                case ImGuiKey_RightShift: mask = 0x0004; break;
+                case ImGuiKey_LeftSuper:  mask = 0x0008; break;
+                case ImGuiKey_RightSuper: mask = 0x0010; break;
+                case ImGuiKey_LeftAlt:    mask = 0x0020; break;
+                case ImGuiKey_RightAlt:   mask = 0x0040; break;
+                default:
+                    return io.WantCaptureKeyboard;
+            }
+
+            NSEventModifierFlags modifier_flags = [event modifierFlags];
+            io.AddKeyEvent(key, (modifier_flags & mask) != 0);
+            io.SetKeyEventNativeData(key, key_code, -1); // To support legacy indexing (<1.87 user code)
+        }
+
+        return io.WantCaptureKeyboard;
+    }
+
+    return false;
+}
+
+static void ImGui_ImplOSX_AddTrackingArea(NSView* _Nonnull view)
+{
+    // If we want to receive key events, we either need to be in the responder chain of the key view,
+    // or else we can install a local monitor. The consequence of this heavy-handed approach is that
+    // we receive events for all controls, not just Dear ImGui widgets. If we had native controls in our
+    // window, we'd want to be much more careful than just ingesting the complete event stream.
+    // To match the behavior of other backends, we pass every event down to the OS.
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    if (bd->Monitor)
+        return;
+    NSEventMask eventMask = 0;
+    eventMask |= NSEventMaskMouseMoved | NSEventMaskScrollWheel;
+    eventMask |= NSEventMaskLeftMouseDown | NSEventMaskLeftMouseUp | NSEventMaskLeftMouseDragged;
+    eventMask |= NSEventMaskRightMouseDown | NSEventMaskRightMouseUp | NSEventMaskRightMouseDragged;
+    eventMask |= NSEventMaskOtherMouseDown | NSEventMaskOtherMouseUp | NSEventMaskOtherMouseDragged;
+    eventMask |= NSEventMaskKeyDown | NSEventMaskKeyUp | NSEventMaskFlagsChanged;
+    bd->Monitor = [NSEvent addLocalMonitorForEventsMatchingMask:eventMask
+                                                        handler:^NSEvent* _Nullable(NSEvent* event)
+    {
+        ImGui_ImplOSX_HandleEvent(event, view);
+        return event;
+    }];
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdl2.cpp

@@ -0,0 +1,659 @@
+// dear imgui: Platform Backend for SDL2
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL2 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+// (Prefer SDL 2.0.5+ for full feature support.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Basic IME support. App needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-04-06: Inputs: Avoid calling SDL_StartTextInput()/SDL_StopTextInput() as they don't only pertain to IME. It's unclear exactly what their relation is to IME. (#6306)
+//  2023-04-04: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_TouchScreen. (#2702)
+//  2023-02-23: Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. (#6189, #6114, #3644)
+//  2023-02-07: Implement IME handler (io.SetPlatformImeDataFn will call SDL_SetTextInputRect()/SDL_StartTextInput()).
+//  2023-02-07: *BREAKING CHANGE* Renamed this backend file from imgui_impl_sdl.cpp/.h to imgui_impl_sdl2.cpp/.h in prevision for the future release of SDL3.
+//  2023-02-02: Avoid calling SDL_SetCursor() when cursor has not changed, as the function is surprisingly costly on Mac with latest SDL (may be fixed in next SDL version).
+//  2023-02-02: Added support for SDL 2.0.18+ preciseX/preciseY mouse wheel data for smooth scrolling + Scaling X value on Emscripten (bug?). (#4019, #6096)
+//  2023-02-02: Removed SDL_MOUSEWHEEL value clamping, as values seem correct in latest Emscripten. (#4019)
+//  2023-02-01: Flipping SDL_MOUSEWHEEL 'wheel.x' value to match other backends and offer consistent horizontal scrolling direction. (#4019, #6096, #1463)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-26: Inputs: Disable SDL 2.0.22 new "auto capture" (SDL_HINT_MOUSE_AUTO_CAPTURE) which prevents drag and drop across windows for multi-viewport support + don't capture when drag and dropping. (#5710)
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-03-22: Inputs: Fix mouse position issues when dragging outside of boundaries. SDL_CaptureMouse() erroneously still gives out LEAVE events when hovering OS decorations.
+//  2022-03-22: Inputs: Added support for extra mouse buttons (SDL_BUTTON_X1/SDL_BUTTON_X2).
+//  2022-02-04: Added SDL_Renderer* parameter to ImGui_ImplSDL2_InitForSDLRenderer(), so we can use SDL_GetRendererOutputSize() instead of SDL_GL_GetDrawableSize() when bound to a SDL_Renderer.
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2021-01-20: Inputs: calling new io.AddKeyAnalogEvent() for gamepad support, instead of writing directly to io.NavInputs[].
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-17: Inputs: always update key mods next and before key event (not in NewFrame) to fix input queue with very low framerates.
+//  2022-01-12: Update mouse inputs using SDL_MOUSEMOTION/SDL_WINDOWEVENT_LEAVE + fallback to provide it when focused but not hovered/captured. More standard and will allow us to pass it to future input queue API.
+//  2022-01-12: Maintain our own copy of MouseButtonsDown mask instead of using ImGui::IsAnyMouseDown() which will be obsoleted.
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-08-17: Calling io.AddFocusEvent() on SDL_WINDOWEVENT_FOCUS_GAINED/SDL_WINDOWEVENT_FOCUS_LOST.
+//  2021-07-29: Inputs: MousePos is correctly reported when the host platform window is hovered but not focused (using SDL_GetMouseFocus() + SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, requires SDL 2.0.5+)
+//  2021-06-29: *BREAKING CHANGE* Removed 'SDL_Window* window' parameter to ImGui_ImplSDL2_NewFrame() which was unnecessary.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-03-22: Rework global mouse pos availability check listing supported platforms explicitly, effectively fixing mouse access on Raspberry Pi. (#2837, #3950)
+//  2020-05-25: Misc: Report a zero display-size when window is minimized, to be consistent with other backends.
+//  2020-02-20: Inputs: Fixed mapping for ImGuiKey_KeyPadEnter (using SDL_SCANCODE_KP_ENTER instead of SDL_SCANCODE_RETURN2).
+//  2019-12-17: Inputs: On Wayland, use SDL_GetMouseState (because there is no global mouse state).
+//  2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
+//  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
+//  2019-04-23: Inputs: Added support for SDL_GameController (if ImGuiConfigFlags_NavEnableGamepad is set by user application).
+//  2019-03-12: Misc: Preserve DisplayFramebufferScale when main window is minimized.
+//  2018-12-21: Inputs: Workaround for Android/iOS which don't seem to handle focus related calls.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-11-14: Changed the signature of ImGui_ImplSDL2_ProcessEvent() to take a 'const SDL_Event*'.
+//  2018-08-01: Inputs: Workaround for Emscripten which doesn't seem to handle focus related calls.
+//  2018-06-29: Inputs: Added support for the ImGuiMouseCursor_Hand cursor.
+//  2018-06-08: Misc: Extracted imgui_impl_sdl.cpp/.h away from the old combined SDL2+OpenGL/Vulkan examples.
+//  2018-06-08: Misc: ImGui_ImplSDL2_InitForOpenGL() now takes a SDL_GLContext parameter.
+//  2018-05-09: Misc: Fixed clipboard paste memory leak (we didn't call SDL_FreeMemory on the data returned by SDL_GetClipboardText).
+//  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-02-16: Inputs: Added support for mouse cursors, honoring ImGui::GetMouseCursor() value.
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
+//  2018-02-05: Misc: Using SDL_GetPerformanceCounter() instead of SDL_GetTicks() to be able to handle very high framerate (1000+ FPS).
+//  2018-02-05: Inputs: Keyboard mapping is using scancodes everywhere instead of a confusing mixture of keycodes and scancodes.
+//  2018-01-20: Inputs: Added Horizontal Mouse Wheel support.
+//  2018-01-19: Inputs: When available (SDL 2.0.4+) using SDL_CaptureMouse() to retrieve coordinates outside of client area when dragging. Otherwise (SDL 2.0.3 and before) testing for SDL_WINDOW_INPUT_FOCUS instead of SDL_WINDOW_MOUSE_FOCUS.
+//  2018-01-18: Inputs: Added mapping for ImGuiKey_Insert.
+//  2017-08-25: Inputs: MousePos set to -FLT_MAX,-FLT_MAX when mouse is unavailable/missing (instead of -1,-1).
+//  2016-10-15: Misc: Added a void* user_data parameter to Clipboard function handlers.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_sdl2.h"
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wimplicit-int-float-conversion"  // warning: implicit conversion from 'xxx' to 'float' may lose precision
+#endif
+
+// SDL
+#include <SDL.h>
+#include <SDL_syswm.h>
+#if defined(__APPLE__)
+#include <TargetConditionals.h>
+#endif
+
+#if SDL_VERSION_ATLEAST(2,0,4) && !defined(__EMSCRIPTEN__) && !defined(__ANDROID__) && !(defined(__APPLE__) && TARGET_OS_IOS) && !defined(__amigaos4__)
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    1
+#else
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    0
+#endif
+#define SDL_HAS_VULKAN                      SDL_VERSION_ATLEAST(2,0,6)
+
+// SDL Data
+struct ImGui_ImplSDL2_Data
+{
+    SDL_Window*     Window;
+    SDL_Renderer*   Renderer;
+    Uint64          Time;
+    Uint32          MouseWindowID;
+    int             MouseButtonsDown;
+    SDL_Cursor*     MouseCursors[ImGuiMouseCursor_COUNT];
+    SDL_Cursor*     LastMouseCursor;
+    int             PendingMouseLeaveFrame;
+    char*           ClipboardTextData;
+    bool            MouseCanUseGlobalState;
+
+    ImGui_ImplSDL2_Data()   { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+// FIXME: some shared resources (mouse cursor shape, gamepad) are mishandled when using multi-context.
+static ImGui_ImplSDL2_Data* ImGui_ImplSDL2_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDL2_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
+}
+
+// Functions
+static const char* ImGui_ImplSDL2_GetClipboardText(void*)
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    bd->ClipboardTextData = SDL_GetClipboardText();
+    return bd->ClipboardTextData;
+}
+
+static void ImGui_ImplSDL2_SetClipboardText(void*, const char* text)
+{
+    SDL_SetClipboardText(text);
+}
+
+// Note: native IME will only display if user calls SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1") _before_ SDL_CreateWindow().
+static void ImGui_ImplSDL2_SetPlatformImeData(ImGuiViewport*, ImGuiPlatformImeData* data)
+{
+    if (data->WantVisible)
+    {
+        SDL_Rect r;
+        r.x = (int)data->InputPos.x;
+        r.y = (int)data->InputPos.y;
+        r.w = 1;
+        r.h = (int)data->InputLineHeight;
+        SDL_SetTextInputRect(&r);
+    }
+}
+
+static ImGuiKey ImGui_ImplSDL2_KeycodeToImGuiKey(int keycode)
+{
+    switch (keycode)
+    {
+        case SDLK_TAB: return ImGuiKey_Tab;
+        case SDLK_LEFT: return ImGuiKey_LeftArrow;
+        case SDLK_RIGHT: return ImGuiKey_RightArrow;
+        case SDLK_UP: return ImGuiKey_UpArrow;
+        case SDLK_DOWN: return ImGuiKey_DownArrow;
+        case SDLK_PAGEUP: return ImGuiKey_PageUp;
+        case SDLK_PAGEDOWN: return ImGuiKey_PageDown;
+        case SDLK_HOME: return ImGuiKey_Home;
+        case SDLK_END: return ImGuiKey_End;
+        case SDLK_INSERT: return ImGuiKey_Insert;
+        case SDLK_DELETE: return ImGuiKey_Delete;
+        case SDLK_BACKSPACE: return ImGuiKey_Backspace;
+        case SDLK_SPACE: return ImGuiKey_Space;
+        case SDLK_RETURN: return ImGuiKey_Enter;
+        case SDLK_ESCAPE: return ImGuiKey_Escape;
+        case SDLK_QUOTE: return ImGuiKey_Apostrophe;
+        case SDLK_COMMA: return ImGuiKey_Comma;
+        case SDLK_MINUS: return ImGuiKey_Minus;
+        case SDLK_PERIOD: return ImGuiKey_Period;
+        case SDLK_SLASH: return ImGuiKey_Slash;
+        case SDLK_SEMICOLON: return ImGuiKey_Semicolon;
+        case SDLK_EQUALS: return ImGuiKey_Equal;
+        case SDLK_LEFTBRACKET: return ImGuiKey_LeftBracket;
+        case SDLK_BACKSLASH: return ImGuiKey_Backslash;
+        case SDLK_RIGHTBRACKET: return ImGuiKey_RightBracket;
+        case SDLK_BACKQUOTE: return ImGuiKey_GraveAccent;
+        case SDLK_CAPSLOCK: return ImGuiKey_CapsLock;
+        case SDLK_SCROLLLOCK: return ImGuiKey_ScrollLock;
+        case SDLK_NUMLOCKCLEAR: return ImGuiKey_NumLock;
+        case SDLK_PRINTSCREEN: return ImGuiKey_PrintScreen;
+        case SDLK_PAUSE: return ImGuiKey_Pause;
+        case SDLK_KP_0: return ImGuiKey_Keypad0;
+        case SDLK_KP_1: return ImGuiKey_Keypad1;
+        case SDLK_KP_2: return ImGuiKey_Keypad2;
+        case SDLK_KP_3: return ImGuiKey_Keypad3;
+        case SDLK_KP_4: return ImGuiKey_Keypad4;
+        case SDLK_KP_5: return ImGuiKey_Keypad5;
+        case SDLK_KP_6: return ImGuiKey_Keypad6;
+        case SDLK_KP_7: return ImGuiKey_Keypad7;
+        case SDLK_KP_8: return ImGuiKey_Keypad8;
+        case SDLK_KP_9: return ImGuiKey_Keypad9;
+        case SDLK_KP_PERIOD: return ImGuiKey_KeypadDecimal;
+        case SDLK_KP_DIVIDE: return ImGuiKey_KeypadDivide;
+        case SDLK_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case SDLK_KP_MINUS: return ImGuiKey_KeypadSubtract;
+        case SDLK_KP_PLUS: return ImGuiKey_KeypadAdd;
+        case SDLK_KP_ENTER: return ImGuiKey_KeypadEnter;
+        case SDLK_KP_EQUALS: return ImGuiKey_KeypadEqual;
+        case SDLK_LCTRL: return ImGuiKey_LeftCtrl;
+        case SDLK_LSHIFT: return ImGuiKey_LeftShift;
+        case SDLK_LALT: return ImGuiKey_LeftAlt;
+        case SDLK_LGUI: return ImGuiKey_LeftSuper;
+        case SDLK_RCTRL: return ImGuiKey_RightCtrl;
+        case SDLK_RSHIFT: return ImGuiKey_RightShift;
+        case SDLK_RALT: return ImGuiKey_RightAlt;
+        case SDLK_RGUI: return ImGuiKey_RightSuper;
+        case SDLK_APPLICATION: return ImGuiKey_Menu;
+        case SDLK_0: return ImGuiKey_0;
+        case SDLK_1: return ImGuiKey_1;
+        case SDLK_2: return ImGuiKey_2;
+        case SDLK_3: return ImGuiKey_3;
+        case SDLK_4: return ImGuiKey_4;
+        case SDLK_5: return ImGuiKey_5;
+        case SDLK_6: return ImGuiKey_6;
+        case SDLK_7: return ImGuiKey_7;
+        case SDLK_8: return ImGuiKey_8;
+        case SDLK_9: return ImGuiKey_9;
+        case SDLK_a: return ImGuiKey_A;
+        case SDLK_b: return ImGuiKey_B;
+        case SDLK_c: return ImGuiKey_C;
+        case SDLK_d: return ImGuiKey_D;
+        case SDLK_e: return ImGuiKey_E;
+        case SDLK_f: return ImGuiKey_F;
+        case SDLK_g: return ImGuiKey_G;
+        case SDLK_h: return ImGuiKey_H;
+        case SDLK_i: return ImGuiKey_I;
+        case SDLK_j: return ImGuiKey_J;
+        case SDLK_k: return ImGuiKey_K;
+        case SDLK_l: return ImGuiKey_L;
+        case SDLK_m: return ImGuiKey_M;
+        case SDLK_n: return ImGuiKey_N;
+        case SDLK_o: return ImGuiKey_O;
+        case SDLK_p: return ImGuiKey_P;
+        case SDLK_q: return ImGuiKey_Q;
+        case SDLK_r: return ImGuiKey_R;
+        case SDLK_s: return ImGuiKey_S;
+        case SDLK_t: return ImGuiKey_T;
+        case SDLK_u: return ImGuiKey_U;
+        case SDLK_v: return ImGuiKey_V;
+        case SDLK_w: return ImGuiKey_W;
+        case SDLK_x: return ImGuiKey_X;
+        case SDLK_y: return ImGuiKey_Y;
+        case SDLK_z: return ImGuiKey_Z;
+        case SDLK_F1: return ImGuiKey_F1;
+        case SDLK_F2: return ImGuiKey_F2;
+        case SDLK_F3: return ImGuiKey_F3;
+        case SDLK_F4: return ImGuiKey_F4;
+        case SDLK_F5: return ImGuiKey_F5;
+        case SDLK_F6: return ImGuiKey_F6;
+        case SDLK_F7: return ImGuiKey_F7;
+        case SDLK_F8: return ImGuiKey_F8;
+        case SDLK_F9: return ImGuiKey_F9;
+        case SDLK_F10: return ImGuiKey_F10;
+        case SDLK_F11: return ImGuiKey_F11;
+        case SDLK_F12: return ImGuiKey_F12;
+    }
+    return ImGuiKey_None;
+}
+
+static void ImGui_ImplSDL2_UpdateKeyModifiers(SDL_Keymod sdl_key_mods)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(ImGuiMod_Ctrl, (sdl_key_mods & KMOD_CTRL) != 0);
+    io.AddKeyEvent(ImGuiMod_Shift, (sdl_key_mods & KMOD_SHIFT) != 0);
+    io.AddKeyEvent(ImGuiMod_Alt, (sdl_key_mods & KMOD_ALT) != 0);
+    io.AddKeyEvent(ImGuiMod_Super, (sdl_key_mods & KMOD_GUI) != 0);
+}
+
+// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
+bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+
+    switch (event->type)
+    {
+        case SDL_MOUSEMOTION:
+        {
+            ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            io.AddMouseSourceEvent(event->motion.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
+            return true;
+        }
+        case SDL_MOUSEWHEEL:
+        {
+            //IMGUI_DEBUG_LOG("wheel %.2f %.2f, precise %.2f %.2f\n", (float)event->wheel.x, (float)event->wheel.y, event->wheel.preciseX, event->wheel.preciseY);
+#if SDL_VERSION_ATLEAST(2,0,18) // If this fails to compile on Emscripten: update to latest Emscripten!
+            float wheel_x = -event->wheel.preciseX;
+            float wheel_y = event->wheel.preciseY;
+#else
+            float wheel_x = -(float)event->wheel.x;
+            float wheel_y = (float)event->wheel.y;
+#endif
+#ifdef __EMSCRIPTEN__
+            wheel_x /= 100.0f;
+#endif
+            io.AddMouseSourceEvent(event->wheel.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseWheelEvent(wheel_x, wheel_y);
+            return true;
+        }
+        case SDL_MOUSEBUTTONDOWN:
+        case SDL_MOUSEBUTTONUP:
+        {
+            int mouse_button = -1;
+            if (event->button.button == SDL_BUTTON_LEFT) { mouse_button = 0; }
+            if (event->button.button == SDL_BUTTON_RIGHT) { mouse_button = 1; }
+            if (event->button.button == SDL_BUTTON_MIDDLE) { mouse_button = 2; }
+            if (event->button.button == SDL_BUTTON_X1) { mouse_button = 3; }
+            if (event->button.button == SDL_BUTTON_X2) { mouse_button = 4; }
+            if (mouse_button == -1)
+                break;
+            io.AddMouseSourceEvent(event->button.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseButtonEvent(mouse_button, (event->type == SDL_MOUSEBUTTONDOWN));
+            bd->MouseButtonsDown = (event->type == SDL_MOUSEBUTTONDOWN) ? (bd->MouseButtonsDown | (1 << mouse_button)) : (bd->MouseButtonsDown & ~(1 << mouse_button));
+            return true;
+        }
+        case SDL_TEXTINPUT:
+        {
+            io.AddInputCharactersUTF8(event->text.text);
+            return true;
+        }
+        case SDL_KEYDOWN:
+        case SDL_KEYUP:
+        {
+            ImGui_ImplSDL2_UpdateKeyModifiers((SDL_Keymod)event->key.keysym.mod);
+            ImGuiKey key = ImGui_ImplSDL2_KeycodeToImGuiKey(event->key.keysym.sym);
+            io.AddKeyEvent(key, (event->type == SDL_KEYDOWN));
+            io.SetKeyEventNativeData(key, event->key.keysym.sym, event->key.keysym.scancode, event->key.keysym.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
+            return true;
+        }
+        case SDL_WINDOWEVENT:
+        {
+            // - When capturing mouse, SDL will send a bunch of conflicting LEAVE/ENTER event on every mouse move, but the final ENTER tends to be right.
+            // - However we won't get a correct LEAVE event for a captured window.
+            // - In some cases, when detaching a window from main viewport SDL may send SDL_WINDOWEVENT_ENTER one frame too late,
+            //   causing SDL_WINDOWEVENT_LEAVE on previous frame to interrupt drag operation by clear mouse position. This is why
+            //   we delay process the SDL_WINDOWEVENT_LEAVE events by one frame. See issue #5012 for details.
+            Uint8 window_event = event->window.event;
+            if (window_event == SDL_WINDOWEVENT_ENTER)
+            {
+                bd->MouseWindowID = event->window.windowID;
+                bd->PendingMouseLeaveFrame = 0;
+            }
+            if (window_event == SDL_WINDOWEVENT_LEAVE)
+                bd->PendingMouseLeaveFrame = ImGui::GetFrameCount() + 1;
+            if (window_event == SDL_WINDOWEVENT_FOCUS_GAINED)
+                io.AddFocusEvent(true);
+            else if (event->window.event == SDL_WINDOWEVENT_FOCUS_LOST)
+                io.AddFocusEvent(false);
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+
+    // Check and store if we are on a SDL backend that supports global mouse position
+    // ("wayland" and "rpi" don't support it, but we chose to use a white-list instead of a black-list)
+    bool mouse_can_use_global_state = false;
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+    const char* sdl_backend = SDL_GetCurrentVideoDriver();
+    const char* global_mouse_whitelist[] = { "windows", "cocoa", "x11", "DIVE", "VMAN" };
+    for (int n = 0; n < IM_ARRAYSIZE(global_mouse_whitelist); n++)
+        if (strncmp(sdl_backend, global_mouse_whitelist[n], strlen(global_mouse_whitelist[n])) == 0)
+            mouse_can_use_global_state = true;
+#endif
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDL2_Data* bd = IM_NEW(ImGui_ImplSDL2_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = "imgui_impl_sdl2";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;       // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;        // We can honor io.WantSetMousePos requests (optional, rarely used)
+
+    bd->Window = window;
+    bd->Renderer = renderer;
+    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
+
+    io.SetClipboardTextFn = ImGui_ImplSDL2_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplSDL2_GetClipboardText;
+    io.ClipboardUserData = nullptr;
+    io.SetPlatformImeDataFn = ImGui_ImplSDL2_SetPlatformImeData;
+
+    // Load mouse cursors
+    bd->MouseCursors[ImGuiMouseCursor_Arrow] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+    bd->MouseCursors[ImGuiMouseCursor_TextInput] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_IBEAM);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEALL);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNS] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENS);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeEW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEWE);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENESW);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENWSE);
+    bd->MouseCursors[ImGuiMouseCursor_Hand] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_HAND);
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_NO);
+
+    // Set platform dependent data in viewport
+    // Our mouse update function expect PlatformHandle to be filled for the main viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandleRaw = nullptr;
+    SDL_SysWMinfo info;
+    SDL_VERSION(&info.version);
+    if (SDL_GetWindowWMInfo(window, &info))
+    {
+#if defined(SDL_VIDEO_DRIVER_WINDOWS)
+        main_viewport->PlatformHandleRaw = (void*)info.info.win.window;
+#elif defined(__APPLE__) && defined(SDL_VIDEO_DRIVER_COCOA)
+        main_viewport->PlatformHandleRaw = (void*)info.info.cocoa.window;
+#endif
+    }
+
+    // From 2.0.5: Set SDL hint to receive mouse click events on window focus, otherwise SDL doesn't emit the event.
+    // Without this, when clicking to gain focus, our widgets wouldn't activate even though they showed as hovered.
+    // (This is unfortunately a global SDL setting, so enabling it might have a side-effect on your application.
+    // It is unlikely to make a difference, but if your app absolutely needs to ignore the initial on-focus click:
+    // you can ignore SDL_MOUSEBUTTONDOWN events coming right after a SDL_WINDOWEVENT_FOCUS_GAINED)
+#ifdef SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH
+    SDL_SetHint(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, "1");
+#endif
+
+    // From 2.0.18: Enable native IME.
+    // IMPORTANT: This is used at the time of SDL_CreateWindow() so this will only affects secondary windows, if any.
+    // For the main window to be affected, your application needs to call this manually before calling SDL_CreateWindow().
+#ifdef SDL_HINT_IME_SHOW_UI
+    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
+#endif
+
+    // From 2.0.22: Disable auto-capture, this is preventing drag and drop across multiple windows (see #5710)
+#ifdef SDL_HINT_MOUSE_AUTO_CAPTURE
+    SDL_SetHint(SDL_HINT_MOUSE_AUTO_CAPTURE, "0");
+#endif
+
+    return true;
+}
+
+bool ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
+{
+    IM_UNUSED(sdl_gl_context); // Viewport branch will need this.
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForVulkan(SDL_Window* window)
+{
+#if !SDL_HAS_VULKAN
+    IM_ASSERT(0 && "Unsupported");
+#endif
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForD3D(SDL_Window* window)
+{
+#if !defined(_WIN32)
+    IM_ASSERT(0 && "Unsupported");
+#endif
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForMetal(SDL_Window* window)
+{
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer)
+{
+    return ImGui_ImplSDL2_Init(window, renderer);
+}
+
+bool ImGui_ImplSDL2_InitForOther(SDL_Window* window)
+{
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+void ImGui_ImplSDL2_Shutdown()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
+        SDL_FreeCursor(bd->MouseCursors[cursor_n]);
+    bd->LastMouseCursor = nullptr;
+
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDL2_UpdateMouseData()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // We forward mouse input when hovered or captured (via SDL_MOUSEMOTION) or when focused (below)
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+    // SDL_CaptureMouse() let the OS know e.g. that our imgui drag outside the SDL window boundaries shouldn't e.g. trigger other operations outside
+    SDL_CaptureMouse((bd->MouseButtonsDown != 0) ? SDL_TRUE : SDL_FALSE);
+    SDL_Window* focused_window = SDL_GetKeyboardFocus();
+    const bool is_app_focused = (bd->Window == focused_window);
+#else
+    const bool is_app_focused = (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0; // SDL 2.0.3 and non-windowed systems: single-viewport only
+#endif
+    if (is_app_focused)
+    {
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        if (io.WantSetMousePos)
+            SDL_WarpMouseInWindow(bd->Window, (int)io.MousePos.x, (int)io.MousePos.y);
+
+        // (Optional) Fallback to provide mouse position when focused (SDL_MOUSEMOTION already provides this when hovered or captured)
+        if (bd->MouseCanUseGlobalState && bd->MouseButtonsDown == 0)
+        {
+            int window_x, window_y, mouse_x_global, mouse_y_global;
+            SDL_GetGlobalMouseState(&mouse_x_global, &mouse_y_global);
+            SDL_GetWindowPosition(bd->Window, &window_x, &window_y);
+            io.AddMousePosEvent((float)(mouse_x_global - window_x), (float)(mouse_y_global - window_y));
+        }
+    }
+}
+
+static void ImGui_ImplSDL2_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return;
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        SDL_ShowCursor(SDL_FALSE);
+    }
+    else
+    {
+        // Show OS mouse cursor
+        SDL_Cursor* expected_cursor = bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow];
+        if (bd->LastMouseCursor != expected_cursor)
+        {
+            SDL_SetCursor(expected_cursor); // SDL function doesn't have an early out (see #6113)
+            bd->LastMouseCursor = expected_cursor;
+        }
+        SDL_ShowCursor(SDL_TRUE);
+    }
+}
+
+static void ImGui_ImplSDL2_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+        return;
+
+    // Get gamepad
+    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+    SDL_GameController* game_controller = SDL_GameControllerOpen(0);
+    if (!game_controller)
+        return;
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+
+    // Update gamepad inputs
+    #define IM_SATURATE(V)                      (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V)
+    #define MAP_BUTTON(KEY_NO, BUTTON_NO)       { io.AddKeyEvent(KEY_NO, SDL_GameControllerGetButton(game_controller, BUTTON_NO) != 0); }
+    #define MAP_ANALOG(KEY_NO, AXIS_NO, V0, V1) { float vn = (float)(SDL_GameControllerGetAxis(game_controller, AXIS_NO) - V0) / (float)(V1 - V0); vn = IM_SATURATE(vn); io.AddKeyAnalogEvent(KEY_NO, vn > 0.1f, vn); }
+    const int thumb_dead_zone = 8000;           // SDL_gamecontroller.h suggests using this value.
+    MAP_BUTTON(ImGuiKey_GamepadStart,           SDL_CONTROLLER_BUTTON_START);
+    MAP_BUTTON(ImGuiKey_GamepadBack,            SDL_CONTROLLER_BUTTON_BACK);
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,        SDL_CONTROLLER_BUTTON_X);              // Xbox X, PS Square
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,       SDL_CONTROLLER_BUTTON_B);              // Xbox B, PS Circle
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,          SDL_CONTROLLER_BUTTON_Y);              // Xbox Y, PS Triangle
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,        SDL_CONTROLLER_BUTTON_A);              // Xbox A, PS Cross
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,        SDL_CONTROLLER_BUTTON_DPAD_LEFT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,       SDL_CONTROLLER_BUTTON_DPAD_RIGHT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,          SDL_CONTROLLER_BUTTON_DPAD_UP);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,        SDL_CONTROLLER_BUTTON_DPAD_DOWN);
+    MAP_BUTTON(ImGuiKey_GamepadL1,              SDL_CONTROLLER_BUTTON_LEFTSHOULDER);
+    MAP_BUTTON(ImGuiKey_GamepadR1,              SDL_CONTROLLER_BUTTON_RIGHTSHOULDER);
+    MAP_ANALOG(ImGuiKey_GamepadL2,              SDL_CONTROLLER_AXIS_TRIGGERLEFT,  0.0f, 32767);
+    MAP_ANALOG(ImGuiKey_GamepadR2,              SDL_CONTROLLER_AXIS_TRIGGERRIGHT, 0.0f, 32767);
+    MAP_BUTTON(ImGuiKey_GamepadL3,              SDL_CONTROLLER_BUTTON_LEFTSTICK);
+    MAP_BUTTON(ImGuiKey_GamepadR3,              SDL_CONTROLLER_BUTTON_RIGHTSTICK);
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,      SDL_CONTROLLER_AXIS_LEFTX,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight,     SDL_CONTROLLER_AXIS_LEFTX,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,        SDL_CONTROLLER_AXIS_LEFTY,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,      SDL_CONTROLLER_AXIS_LEFTY,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,      SDL_CONTROLLER_AXIS_RIGHTX, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight,     SDL_CONTROLLER_AXIS_RIGHTX, +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,        SDL_CONTROLLER_AXIS_RIGHTY, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,      SDL_CONTROLLER_AXIS_RIGHTY, +thumb_dead_zone, +32767);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+}
+
+void ImGui_ImplSDL2_NewFrame()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDL2_Init()?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    int display_w, display_h;
+    SDL_GetWindowSize(bd->Window, &w, &h);
+    if (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_MINIMIZED)
+        w = h = 0;
+    if (bd->Renderer != nullptr)
+        SDL_GetRendererOutputSize(bd->Renderer, &display_w, &display_h);
+    else
+        SDL_GL_GetDrawableSize(bd->Window, &display_w, &display_h);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+    if (w > 0 && h > 0)
+        io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
+
+    // Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
+    // (Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. Happens in VMs and Emscripten, see #6189, #6114, #3644)
+    static Uint64 frequency = SDL_GetPerformanceFrequency();
+    Uint64 current_time = SDL_GetPerformanceCounter();
+    if (current_time <= bd->Time)
+        current_time = bd->Time + 1;
+    io.DeltaTime = bd->Time > 0 ? (float)((double)(current_time - bd->Time) / frequency) : (float)(1.0f / 60.0f);
+    bd->Time = current_time;
+
+    if (bd->PendingMouseLeaveFrame && bd->PendingMouseLeaveFrame >= ImGui::GetFrameCount() && bd->MouseButtonsDown == 0)
+    {
+        bd->MouseWindowID = 0;
+        bd->PendingMouseLeaveFrame = 0;
+        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+    }
+
+    ImGui_ImplSDL2_UpdateMouseData();
+    ImGui_ImplSDL2_UpdateMouseCursor();
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplSDL2_UpdateGamepads();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdl2.h

@@ -0,0 +1,43 @@
+// dear imgui: Platform Backend for SDL2
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL2 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Basic IME support. App needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct SDL_Window;
+struct SDL_Renderer;
+typedef union SDL_Event SDL_Event;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForVulkan(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForD3D(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForMetal(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOther(SDL_Window* window);
+IMGUI_IMPL_API void     ImGui_ImplSDL2_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDL2_NewFrame();
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event);
+
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+static inline void ImGui_ImplSDL2_NewFrame(SDL_Window*) { ImGui_ImplSDL2_NewFrame(); } // 1.84: removed unnecessary parameter
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdl3.cpp

@@ -0,0 +1,594 @@
+// dear imgui: Platform Backend for SDL3 (*EXPERIMENTAL*)
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL3 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+// (IMPORTANT: SDL 3.0.0 is NOT YET RELEASED. IT IS POSSIBLE THAT ITS SPECS/API WILL CHANGE BEFORE RELEASE)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Missing features:
+//  [x] Platform: Basic IME support. Position somehow broken in SDL3 + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-05-04: Fixed build on Emscripten/iOS/Android. (#6391)
+//  2023-04-06: Inputs: Avoid calling SDL_StartTextInput()/SDL_StopTextInput() as they don't only pertain to IME. It's unclear exactly what their relation is to IME. (#6306)
+//  2023-04-04: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_TouchScreen. (#2702)
+//  2023-02-23: Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. (#6189, #6114, #3644)
+//  2023-02-07: Forked "imgui_impl_sdl2" into "imgui_impl_sdl3". Removed version checks for old feature. Refer to imgui_impl_sdl2.cpp for older changelog.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_sdl3.h"
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wimplicit-int-float-conversion"  // warning: implicit conversion from 'xxx' to 'float' may lose precision
+#endif
+
+// SDL
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_syswm.h>
+#if defined(__APPLE__)
+#include <TargetConditionals.h>
+#endif
+
+#if !defined(__EMSCRIPTEN__) && !defined(__ANDROID__) && !(defined(__APPLE__) && TARGET_OS_IOS) && !defined(__amigaos4__)
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    1
+#else
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    0
+#endif
+
+// SDL Data
+struct ImGui_ImplSDL3_Data
+{
+    SDL_Window*     Window;
+    SDL_Renderer*   Renderer;
+    Uint64          Time;
+    Uint32          MouseWindowID;
+    int             MouseButtonsDown;
+    SDL_Cursor*     MouseCursors[ImGuiMouseCursor_COUNT];
+    SDL_Cursor*     LastMouseCursor;
+    int             PendingMouseLeaveFrame;
+    char*           ClipboardTextData;
+    bool            MouseCanUseGlobalState;
+
+    ImGui_ImplSDL3_Data()   { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+// FIXME: some shared resources (mouse cursor shape, gamepad) are mishandled when using multi-context.
+static ImGui_ImplSDL3_Data* ImGui_ImplSDL3_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDL3_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
+}
+
+// Functions
+static const char* ImGui_ImplSDL3_GetClipboardText(void*)
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    bd->ClipboardTextData = SDL_GetClipboardText();
+    return bd->ClipboardTextData;
+}
+
+static void ImGui_ImplSDL3_SetClipboardText(void*, const char* text)
+{
+    SDL_SetClipboardText(text);
+}
+
+static void ImGui_ImplSDL3_SetPlatformImeData(ImGuiViewport*, ImGuiPlatformImeData* data)
+{
+    if (data->WantVisible)
+    {
+        SDL_Rect r;
+        r.x = (int)data->InputPos.x;
+        r.y = (int)data->InputPos.y;
+        r.w = 1;
+        r.h = (int)data->InputLineHeight;
+        SDL_SetTextInputRect(&r);
+    }
+}
+
+static ImGuiKey ImGui_ImplSDL3_KeycodeToImGuiKey(int keycode)
+{
+    switch (keycode)
+    {
+        case SDLK_TAB: return ImGuiKey_Tab;
+        case SDLK_LEFT: return ImGuiKey_LeftArrow;
+        case SDLK_RIGHT: return ImGuiKey_RightArrow;
+        case SDLK_UP: return ImGuiKey_UpArrow;
+        case SDLK_DOWN: return ImGuiKey_DownArrow;
+        case SDLK_PAGEUP: return ImGuiKey_PageUp;
+        case SDLK_PAGEDOWN: return ImGuiKey_PageDown;
+        case SDLK_HOME: return ImGuiKey_Home;
+        case SDLK_END: return ImGuiKey_End;
+        case SDLK_INSERT: return ImGuiKey_Insert;
+        case SDLK_DELETE: return ImGuiKey_Delete;
+        case SDLK_BACKSPACE: return ImGuiKey_Backspace;
+        case SDLK_SPACE: return ImGuiKey_Space;
+        case SDLK_RETURN: return ImGuiKey_Enter;
+        case SDLK_ESCAPE: return ImGuiKey_Escape;
+        case SDLK_QUOTE: return ImGuiKey_Apostrophe;
+        case SDLK_COMMA: return ImGuiKey_Comma;
+        case SDLK_MINUS: return ImGuiKey_Minus;
+        case SDLK_PERIOD: return ImGuiKey_Period;
+        case SDLK_SLASH: return ImGuiKey_Slash;
+        case SDLK_SEMICOLON: return ImGuiKey_Semicolon;
+        case SDLK_EQUALS: return ImGuiKey_Equal;
+        case SDLK_LEFTBRACKET: return ImGuiKey_LeftBracket;
+        case SDLK_BACKSLASH: return ImGuiKey_Backslash;
+        case SDLK_RIGHTBRACKET: return ImGuiKey_RightBracket;
+        case SDLK_BACKQUOTE: return ImGuiKey_GraveAccent;
+        case SDLK_CAPSLOCK: return ImGuiKey_CapsLock;
+        case SDLK_SCROLLLOCK: return ImGuiKey_ScrollLock;
+        case SDLK_NUMLOCKCLEAR: return ImGuiKey_NumLock;
+        case SDLK_PRINTSCREEN: return ImGuiKey_PrintScreen;
+        case SDLK_PAUSE: return ImGuiKey_Pause;
+        case SDLK_KP_0: return ImGuiKey_Keypad0;
+        case SDLK_KP_1: return ImGuiKey_Keypad1;
+        case SDLK_KP_2: return ImGuiKey_Keypad2;
+        case SDLK_KP_3: return ImGuiKey_Keypad3;
+        case SDLK_KP_4: return ImGuiKey_Keypad4;
+        case SDLK_KP_5: return ImGuiKey_Keypad5;
+        case SDLK_KP_6: return ImGuiKey_Keypad6;
+        case SDLK_KP_7: return ImGuiKey_Keypad7;
+        case SDLK_KP_8: return ImGuiKey_Keypad8;
+        case SDLK_KP_9: return ImGuiKey_Keypad9;
+        case SDLK_KP_PERIOD: return ImGuiKey_KeypadDecimal;
+        case SDLK_KP_DIVIDE: return ImGuiKey_KeypadDivide;
+        case SDLK_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case SDLK_KP_MINUS: return ImGuiKey_KeypadSubtract;
+        case SDLK_KP_PLUS: return ImGuiKey_KeypadAdd;
+        case SDLK_KP_ENTER: return ImGuiKey_KeypadEnter;
+        case SDLK_KP_EQUALS: return ImGuiKey_KeypadEqual;
+        case SDLK_LCTRL: return ImGuiKey_LeftCtrl;
+        case SDLK_LSHIFT: return ImGuiKey_LeftShift;
+        case SDLK_LALT: return ImGuiKey_LeftAlt;
+        case SDLK_LGUI: return ImGuiKey_LeftSuper;
+        case SDLK_RCTRL: return ImGuiKey_RightCtrl;
+        case SDLK_RSHIFT: return ImGuiKey_RightShift;
+        case SDLK_RALT: return ImGuiKey_RightAlt;
+        case SDLK_RGUI: return ImGuiKey_RightSuper;
+        case SDLK_APPLICATION: return ImGuiKey_Menu;
+        case SDLK_0: return ImGuiKey_0;
+        case SDLK_1: return ImGuiKey_1;
+        case SDLK_2: return ImGuiKey_2;
+        case SDLK_3: return ImGuiKey_3;
+        case SDLK_4: return ImGuiKey_4;
+        case SDLK_5: return ImGuiKey_5;
+        case SDLK_6: return ImGuiKey_6;
+        case SDLK_7: return ImGuiKey_7;
+        case SDLK_8: return ImGuiKey_8;
+        case SDLK_9: return ImGuiKey_9;
+        case SDLK_a: return ImGuiKey_A;
+        case SDLK_b: return ImGuiKey_B;
+        case SDLK_c: return ImGuiKey_C;
+        case SDLK_d: return ImGuiKey_D;
+        case SDLK_e: return ImGuiKey_E;
+        case SDLK_f: return ImGuiKey_F;
+        case SDLK_g: return ImGuiKey_G;
+        case SDLK_h: return ImGuiKey_H;
+        case SDLK_i: return ImGuiKey_I;
+        case SDLK_j: return ImGuiKey_J;
+        case SDLK_k: return ImGuiKey_K;
+        case SDLK_l: return ImGuiKey_L;
+        case SDLK_m: return ImGuiKey_M;
+        case SDLK_n: return ImGuiKey_N;
+        case SDLK_o: return ImGuiKey_O;
+        case SDLK_p: return ImGuiKey_P;
+        case SDLK_q: return ImGuiKey_Q;
+        case SDLK_r: return ImGuiKey_R;
+        case SDLK_s: return ImGuiKey_S;
+        case SDLK_t: return ImGuiKey_T;
+        case SDLK_u: return ImGuiKey_U;
+        case SDLK_v: return ImGuiKey_V;
+        case SDLK_w: return ImGuiKey_W;
+        case SDLK_x: return ImGuiKey_X;
+        case SDLK_y: return ImGuiKey_Y;
+        case SDLK_z: return ImGuiKey_Z;
+        case SDLK_F1: return ImGuiKey_F1;
+        case SDLK_F2: return ImGuiKey_F2;
+        case SDLK_F3: return ImGuiKey_F3;
+        case SDLK_F4: return ImGuiKey_F4;
+        case SDLK_F5: return ImGuiKey_F5;
+        case SDLK_F6: return ImGuiKey_F6;
+        case SDLK_F7: return ImGuiKey_F7;
+        case SDLK_F8: return ImGuiKey_F8;
+        case SDLK_F9: return ImGuiKey_F9;
+        case SDLK_F10: return ImGuiKey_F10;
+        case SDLK_F11: return ImGuiKey_F11;
+        case SDLK_F12: return ImGuiKey_F12;
+    }
+    return ImGuiKey_None;
+}
+
+static void ImGui_ImplSDL3_UpdateKeyModifiers(SDL_Keymod sdl_key_mods)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(ImGuiMod_Ctrl, (sdl_key_mods & SDL_KMOD_CTRL) != 0);
+    io.AddKeyEvent(ImGuiMod_Shift, (sdl_key_mods & SDL_KMOD_SHIFT) != 0);
+    io.AddKeyEvent(ImGuiMod_Alt, (sdl_key_mods & SDL_KMOD_ALT) != 0);
+    io.AddKeyEvent(ImGuiMod_Super, (sdl_key_mods & SDL_KMOD_GUI) != 0);
+}
+
+// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
+bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+
+    switch (event->type)
+    {
+        case SDL_EVENT_MOUSE_MOTION:
+        {
+            ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            io.AddMouseSourceEvent(event->motion.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
+            return true;
+        }
+        case SDL_EVENT_MOUSE_WHEEL:
+        {
+            //IMGUI_DEBUG_LOG("wheel %.2f %.2f, precise %.2f %.2f\n", (float)event->wheel.x, (float)event->wheel.y, event->wheel.preciseX, event->wheel.preciseY);
+            float wheel_x = -event->wheel.x;
+            float wheel_y = event->wheel.y;
+    #ifdef __EMSCRIPTEN__
+            wheel_x /= 100.0f;
+    #endif
+            io.AddMouseSourceEvent(event->wheel.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseWheelEvent(wheel_x, wheel_y);
+            return true;
+        }
+        case SDL_EVENT_MOUSE_BUTTON_DOWN:
+        case SDL_EVENT_MOUSE_BUTTON_UP:
+        {
+            int mouse_button = -1;
+            if (event->button.button == SDL_BUTTON_LEFT) { mouse_button = 0; }
+            if (event->button.button == SDL_BUTTON_RIGHT) { mouse_button = 1; }
+            if (event->button.button == SDL_BUTTON_MIDDLE) { mouse_button = 2; }
+            if (event->button.button == SDL_BUTTON_X1) { mouse_button = 3; }
+            if (event->button.button == SDL_BUTTON_X2) { mouse_button = 4; }
+            if (mouse_button == -1)
+                break;
+            io.AddMouseSourceEvent(event->button.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseButtonEvent(mouse_button, (event->type == SDL_EVENT_MOUSE_BUTTON_DOWN));
+            bd->MouseButtonsDown = (event->type == SDL_EVENT_MOUSE_BUTTON_DOWN) ? (bd->MouseButtonsDown | (1 << mouse_button)) : (bd->MouseButtonsDown & ~(1 << mouse_button));
+            return true;
+        }
+        case SDL_EVENT_TEXT_INPUT:
+        {
+            io.AddInputCharactersUTF8(event->text.text);
+            return true;
+        }
+        case SDL_EVENT_KEY_DOWN:
+        case SDL_EVENT_KEY_UP:
+        {
+            ImGui_ImplSDL3_UpdateKeyModifiers((SDL_Keymod)event->key.keysym.mod);
+            ImGuiKey key = ImGui_ImplSDL3_KeycodeToImGuiKey(event->key.keysym.sym);
+            io.AddKeyEvent(key, (event->type == SDL_EVENT_KEY_DOWN));
+            io.SetKeyEventNativeData(key, event->key.keysym.sym, event->key.keysym.scancode, event->key.keysym.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
+            return true;
+        }
+        case SDL_EVENT_WINDOW_MOUSE_ENTER:
+        {
+            bd->MouseWindowID = event->window.windowID;
+            bd->PendingMouseLeaveFrame = 0;
+            return true;
+        }
+        // - In some cases, when detaching a window from main viewport SDL may send SDL_WINDOWEVENT_ENTER one frame too late,
+        //   causing SDL_WINDOWEVENT_LEAVE on previous frame to interrupt drag operation by clear mouse position. This is why
+        //   we delay process the SDL_WINDOWEVENT_LEAVE events by one frame. See issue #5012 for details.
+        // FIXME: Unconfirmed whether this is still needed with SDL3.
+        case SDL_EVENT_WINDOW_MOUSE_LEAVE:
+        {
+            bd->PendingMouseLeaveFrame = ImGui::GetFrameCount() + 1;
+            return true;
+        }
+        case SDL_EVENT_WINDOW_FOCUS_GAINED:
+            io.AddFocusEvent(true);
+            return true;
+        case SDL_EVENT_WINDOW_FOCUS_LOST:
+            io.AddFocusEvent(false);
+            return true;
+    }
+    return false;
+}
+
+static bool ImGui_ImplSDL3_Init(SDL_Window* window, SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+
+    // Check and store if we are on a SDL backend that supports global mouse position
+    // ("wayland" and "rpi" don't support it, but we chose to use a white-list instead of a black-list)
+    bool mouse_can_use_global_state = false;
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+    const char* sdl_backend = SDL_GetCurrentVideoDriver();
+    const char* global_mouse_whitelist[] = { "windows", "cocoa", "x11", "DIVE", "VMAN" };
+    for (int n = 0; n < IM_ARRAYSIZE(global_mouse_whitelist); n++)
+        if (strncmp(sdl_backend, global_mouse_whitelist[n], strlen(global_mouse_whitelist[n])) == 0)
+            mouse_can_use_global_state = true;
+#endif
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDL3_Data* bd = IM_NEW(ImGui_ImplSDL3_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = "imgui_impl_sdl3";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;            // We can honor io.WantSetMousePos requests (optional, rarely used)
+
+    bd->Window = window;
+    bd->Renderer = renderer;
+    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
+
+    io.SetClipboardTextFn = ImGui_ImplSDL3_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplSDL3_GetClipboardText;
+    io.ClipboardUserData = nullptr;
+    io.SetPlatformImeDataFn = ImGui_ImplSDL3_SetPlatformImeData;
+
+    // Load mouse cursors
+    bd->MouseCursors[ImGuiMouseCursor_Arrow] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+    bd->MouseCursors[ImGuiMouseCursor_TextInput] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_IBEAM);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEALL);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNS] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENS);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeEW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEWE);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENESW);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENWSE);
+    bd->MouseCursors[ImGuiMouseCursor_Hand] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_HAND);
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_NO);
+
+    // Set platform dependent data in viewport
+    // Our mouse update function expect PlatformHandle to be filled for the main viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandleRaw = nullptr;
+    SDL_SysWMinfo info;
+    if (SDL_GetWindowWMInfo(window, &info, SDL_SYSWM_CURRENT_VERSION) == 0)
+    {
+#if defined(SDL_ENABLE_SYSWM_WINDOWS)
+        main_viewport->PlatformHandleRaw = (void*)info.info.win.window;
+#elif defined(__APPLE__) && defined(SDL_ENABLE_SYSWM_COCOA)
+        main_viewport->PlatformHandleRaw = (void*)info.info.cocoa.window;
+#endif
+    }
+
+    // From 2.0.5: Set SDL hint to receive mouse click events on window focus, otherwise SDL doesn't emit the event.
+    // Without this, when clicking to gain focus, our widgets wouldn't activate even though they showed as hovered.
+    // (This is unfortunately a global SDL setting, so enabling it might have a side-effect on your application.
+    // It is unlikely to make a difference, but if your app absolutely needs to ignore the initial on-focus click:
+    // you can ignore SDL_EVENT_MOUSE_BUTTON_DOWN events coming right after a SDL_WINDOWEVENT_FOCUS_GAINED)
+#ifdef SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH
+    SDL_SetHint(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, "1");
+#endif
+
+    // From 2.0.22: Disable auto-capture, this is preventing drag and drop across multiple windows (see #5710)
+#ifdef SDL_HINT_MOUSE_AUTO_CAPTURE
+    SDL_SetHint(SDL_HINT_MOUSE_AUTO_CAPTURE, "0");
+#endif
+
+    return true;
+}
+
+bool ImGui_ImplSDL3_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
+{
+    IM_UNUSED(sdl_gl_context); // Viewport branch will need this.
+    return ImGui_ImplSDL3_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL3_InitForVulkan(SDL_Window* window)
+{
+    return ImGui_ImplSDL3_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL3_InitForD3D(SDL_Window* window)
+{
+#if !defined(_WIN32)
+    IM_ASSERT(0 && "Unsupported");
+#endif
+    return ImGui_ImplSDL3_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL3_InitForMetal(SDL_Window* window)
+{
+    return ImGui_ImplSDL3_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL3_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer)
+{
+    return ImGui_ImplSDL3_Init(window, renderer);
+}
+
+bool ImGui_ImplSDL3_InitForOther(SDL_Window* window)
+{
+    return ImGui_ImplSDL3_Init(window, nullptr);
+}
+
+void ImGui_ImplSDL3_Shutdown()
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
+        SDL_DestroyCursor(bd->MouseCursors[cursor_n]);
+    bd->LastMouseCursor = nullptr;
+
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDL3_UpdateMouseData()
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // We forward mouse input when hovered or captured (via SDL_EVENT_MOUSE_MOTION) or when focused (below)
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+    // SDL_CaptureMouse() let the OS know e.g. that our imgui drag outside the SDL window boundaries shouldn't e.g. trigger other operations outside
+    SDL_CaptureMouse((bd->MouseButtonsDown != 0) ? SDL_TRUE : SDL_FALSE);
+    SDL_Window* focused_window = SDL_GetKeyboardFocus();
+    const bool is_app_focused = (bd->Window == focused_window);
+#else
+    SDL_Window* focused_window = bd->Window;
+    const bool is_app_focused = (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0; // SDL 2.0.3 and non-windowed systems: single-viewport only
+#endif
+    if (is_app_focused)
+    {
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        if (io.WantSetMousePos)
+            SDL_WarpMouseInWindow(bd->Window, io.MousePos.x, io.MousePos.y);
+
+        // (Optional) Fallback to provide mouse position when focused (SDL_EVENT_MOUSE_MOTION already provides this when hovered or captured)
+        if (bd->MouseCanUseGlobalState && bd->MouseButtonsDown == 0)
+        {
+            // Single-viewport mode: mouse position in client window coordinates (io.MousePos is (0,0) when the mouse is on the upper-left corner of the app window)
+            float mouse_x_global, mouse_y_global;
+            int window_x, window_y;
+            SDL_GetGlobalMouseState(&mouse_x_global, &mouse_y_global);
+            SDL_GetWindowPosition(focused_window, &window_x, &window_y);
+            io.AddMousePosEvent(mouse_x_global - window_x, mouse_y_global - window_y);
+        }
+    }
+}
+
+static void ImGui_ImplSDL3_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return;
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        SDL_HideCursor();
+    }
+    else
+    {
+        // Show OS mouse cursor
+        SDL_Cursor* expected_cursor = bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow];
+        if (bd->LastMouseCursor != expected_cursor)
+        {
+            SDL_SetCursor(expected_cursor); // SDL function doesn't have an early out (see #6113)
+            bd->LastMouseCursor = expected_cursor;
+        }
+        SDL_ShowCursor();
+    }
+}
+
+static void ImGui_ImplSDL3_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+        return;
+
+    // Get gamepad
+    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+    SDL_Gamepad* gamepad = SDL_OpenGamepad(0);
+    if (!gamepad)
+        return;
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+
+    // Update gamepad inputs
+    #define IM_SATURATE(V)                      (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V)
+    #define MAP_BUTTON(KEY_NO, BUTTON_NO)       { io.AddKeyEvent(KEY_NO, SDL_GetGamepadButton(gamepad, BUTTON_NO) != 0); }
+    #define MAP_ANALOG(KEY_NO, AXIS_NO, V0, V1) { float vn = (float)(SDL_GetGamepadAxis(gamepad, AXIS_NO) - V0) / (float)(V1 - V0); vn = IM_SATURATE(vn); io.AddKeyAnalogEvent(KEY_NO, vn > 0.1f, vn); }
+    const int thumb_dead_zone = 8000;           // SDL_gamecontroller.h suggests using this value.
+    MAP_BUTTON(ImGuiKey_GamepadStart,           SDL_GAMEPAD_BUTTON_START);
+    MAP_BUTTON(ImGuiKey_GamepadBack,            SDL_GAMEPAD_BUTTON_BACK);
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,        SDL_GAMEPAD_BUTTON_X);              // Xbox X, PS Square
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,       SDL_GAMEPAD_BUTTON_B);              // Xbox B, PS Circle
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,          SDL_GAMEPAD_BUTTON_Y);              // Xbox Y, PS Triangle
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,        SDL_GAMEPAD_BUTTON_A);              // Xbox A, PS Cross
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,        SDL_GAMEPAD_BUTTON_DPAD_LEFT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,       SDL_GAMEPAD_BUTTON_DPAD_RIGHT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,          SDL_GAMEPAD_BUTTON_DPAD_UP);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,        SDL_GAMEPAD_BUTTON_DPAD_DOWN);
+    MAP_BUTTON(ImGuiKey_GamepadL1,              SDL_GAMEPAD_BUTTON_LEFT_SHOULDER);
+    MAP_BUTTON(ImGuiKey_GamepadR1,              SDL_GAMEPAD_BUTTON_RIGHT_SHOULDER);
+    MAP_ANALOG(ImGuiKey_GamepadL2,              SDL_GAMEPAD_AXIS_LEFT_TRIGGER,  0.0f, 32767);
+    MAP_ANALOG(ImGuiKey_GamepadR2,              SDL_GAMEPAD_AXIS_RIGHT_TRIGGER, 0.0f, 32767);
+    MAP_BUTTON(ImGuiKey_GamepadL3,              SDL_GAMEPAD_BUTTON_LEFT_STICK);
+    MAP_BUTTON(ImGuiKey_GamepadR3,              SDL_GAMEPAD_BUTTON_RIGHT_STICK);
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,      SDL_GAMEPAD_AXIS_LEFTX,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight,     SDL_GAMEPAD_AXIS_LEFTX,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,        SDL_GAMEPAD_AXIS_LEFTY,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,      SDL_GAMEPAD_AXIS_LEFTY,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,      SDL_GAMEPAD_AXIS_RIGHTX, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight,     SDL_GAMEPAD_AXIS_RIGHTX, +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,        SDL_GAMEPAD_AXIS_RIGHTY, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,      SDL_GAMEPAD_AXIS_RIGHTY, +thumb_dead_zone, +32767);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+}
+
+void ImGui_ImplSDL3_NewFrame()
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDL3_Init()?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    int display_w, display_h;
+    SDL_GetWindowSize(bd->Window, &w, &h);
+    if (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_MINIMIZED)
+        w = h = 0;
+    SDL_GetWindowSizeInPixels(bd->Window, &display_w, &display_h);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+    if (w > 0 && h > 0)
+        io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
+
+    // Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
+    // (Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. Happens in VMs and Emscripten, see #6189, #6114, #3644)
+    static Uint64 frequency = SDL_GetPerformanceFrequency();
+    Uint64 current_time = SDL_GetPerformanceCounter();
+    if (current_time <= bd->Time)
+        current_time = bd->Time + 1;
+    io.DeltaTime = bd->Time > 0 ? (float)((double)(current_time - bd->Time) / frequency) : (float)(1.0f / 60.0f);
+    bd->Time = current_time;
+
+    if (bd->PendingMouseLeaveFrame && bd->PendingMouseLeaveFrame >= ImGui::GetFrameCount() && bd->MouseButtonsDown == 0)
+    {
+        bd->MouseWindowID = 0;
+        bd->PendingMouseLeaveFrame = 0;
+        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+    }
+
+    ImGui_ImplSDL3_UpdateMouseData();
+    ImGui_ImplSDL3_UpdateMouseCursor();
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplSDL3_UpdateGamepads();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdl3.h

@@ -0,0 +1,41 @@
+// dear imgui: Platform Backend for SDL3 (*EXPERIMENTAL*)
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL3 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+// (IMPORTANT: SDL 3.0.0 is NOT YET RELEASED. IT IS POSSIBLE THAT ITS SPECS/API WILL CHANGE BEFORE RELEASE)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Missing features:
+//  [x] Platform: Basic IME support. Position somehow broken in SDL3 + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct SDL_Window;
+struct SDL_Renderer;
+typedef union SDL_Event SDL_Event;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForVulkan(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForD3D(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForMetal(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer);
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForOther(SDL_Window* window);
+IMGUI_IMPL_API void     ImGui_ImplSDL3_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDL3_NewFrame();
+IMGUI_IMPL_API bool     ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event);
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdlrenderer2.cpp

@@ -0,0 +1,266 @@
+// dear imgui: Renderer Backend for SDL_Renderer for SDL2
+// (Requires: SDL 2.0.17+)
+
+// Note how SDL_Renderer is an _optional_ component of SDL2.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer currently offers a limited graphic API to the end-user and
+// it might be difficult to step out of those boundaries.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+//  2023-05-30: Renamed imgui_impl_sdlrenderer.h/.cpp to imgui_impl_sdlrenderer2.h/.cpp to accommodate for upcoming SDL3.
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-12-21: Update SDL_RenderGeometryRaw() format to work with SDL 2.0.19.
+//  2021-12-03: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2021-10-06: Backup and restore modified ClipRect/Viewport.
+//  2021-09-21: Initial version.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_sdlrenderer2.h"
+#include <stdint.h>     // intptr_t
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"    // warning: implicit conversion changes signedness
+#endif
+
+// SDL
+#include <SDL.h>
+#if !SDL_VERSION_ATLEAST(2,0,17)
+#error This backend requires SDL 2.0.17+ because of SDL_RenderGeometry() function
+#endif
+
+// SDL_Renderer data
+struct ImGui_ImplSDLRenderer2_Data
+{
+    SDL_Renderer*   SDLRenderer;
+    SDL_Texture*    FontTexture;
+    ImGui_ImplSDLRenderer2_Data() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplSDLRenderer2_Data* ImGui_ImplSDLRenderer2_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDLRenderer2_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+bool ImGui_ImplSDLRenderer2_Init(SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+    IM_ASSERT(renderer != nullptr && "SDL_Renderer not initialized!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDLRenderer2_Data* bd = IM_NEW(ImGui_ImplSDLRenderer2_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_sdlrenderer2";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->SDLRenderer = renderer;
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer2_Shutdown()
+{
+    ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplSDLRenderer2_DestroyDeviceObjects();
+
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDLRenderer2_SetupRenderState()
+{
+	ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+
+	// Clear out any viewports and cliprect set by the user
+    // FIXME: Technically speaking there are lots of other things we could backup/setup/restore during our render process.
+	SDL_RenderSetViewport(bd->SDLRenderer, nullptr);
+	SDL_RenderSetClipRect(bd->SDLRenderer, nullptr);
+}
+
+void ImGui_ImplSDLRenderer2_NewFrame()
+{
+    ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDLRenderer2_Init()?");
+
+    if (!bd->FontTexture)
+        ImGui_ImplSDLRenderer2_CreateDeviceObjects();
+}
+
+void ImGui_ImplSDLRenderer2_RenderDrawData(ImDrawData* draw_data)
+{
+	ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+
+	// If there's a scale factor set by the user, use that instead
+    // If the user has specified a scale factor to SDL_Renderer already via SDL_RenderSetScale(), SDL will scale whatever we pass
+    // to SDL_RenderGeometryRaw() by that scale factor. In that case we don't want to be also scaling it ourselves here.
+    float rsx = 1.0f;
+	float rsy = 1.0f;
+	SDL_RenderGetScale(bd->SDLRenderer, &rsx, &rsy);
+    ImVec2 render_scale;
+	render_scale.x = (rsx == 1.0f) ? draw_data->FramebufferScale.x : 1.0f;
+	render_scale.y = (rsy == 1.0f) ? draw_data->FramebufferScale.y : 1.0f;
+
+	// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+	int fb_width = (int)(draw_data->DisplaySize.x * render_scale.x);
+	int fb_height = (int)(draw_data->DisplaySize.y * render_scale.y);
+	if (fb_width == 0 || fb_height == 0)
+		return;
+
+    // Backup SDL_Renderer state that will be modified to restore it afterwards
+    struct BackupSDLRendererState
+    {
+        SDL_Rect    Viewport;
+        bool        ClipEnabled;
+        SDL_Rect    ClipRect;
+    };
+    BackupSDLRendererState old = {};
+    old.ClipEnabled = SDL_RenderIsClipEnabled(bd->SDLRenderer) == SDL_TRUE;
+    SDL_RenderGetViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_RenderGetClipRect(bd->SDLRenderer, &old.ClipRect);
+
+	// Will project scissor/clipping rectangles into framebuffer space
+	ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
+	ImVec2 clip_scale = render_scale;
+
+    // Render command lists
+    ImGui_ImplSDLRenderer2_SetupRenderState();
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplSDLRenderer2_SetupRenderState();
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_min.x < 0.0f) { clip_min.x = 0.0f; }
+                if (clip_min.y < 0.0f) { clip_min.y = 0.0f; }
+                if (clip_max.x > (float)fb_width) { clip_max.x = (float)fb_width; }
+                if (clip_max.y > (float)fb_height) { clip_max.y = (float)fb_height; }
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                SDL_Rect r = { (int)(clip_min.x), (int)(clip_min.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y) };
+                SDL_RenderSetClipRect(bd->SDLRenderer, &r);
+
+                const float* xy = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, pos));
+                const float* uv = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, uv));
+#if SDL_VERSION_ATLEAST(2,0,19)
+                const SDL_Color* color = (const SDL_Color*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.19+
+#else
+                const int* color = (const int*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.17 and 2.0.18
+#endif
+
+                // Bind texture, Draw
+				SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID();
+                SDL_RenderGeometryRaw(bd->SDLRenderer, tex,
+                    xy, (int)sizeof(ImDrawVert),
+                    color, (int)sizeof(ImDrawVert),
+                    uv, (int)sizeof(ImDrawVert),
+                    cmd_list->VtxBuffer.Size - pcmd->VtxOffset,
+                    idx_buffer + pcmd->IdxOffset, pcmd->ElemCount, sizeof(ImDrawIdx));
+            }
+        }
+    }
+
+    // Restore modified SDL_Renderer state
+    SDL_RenderSetViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_RenderSetClipRect(bd->SDLRenderer, old.ClipEnabled ? &old.ClipRect : nullptr);
+}
+
+// Called by Init/NewFrame/Shutdown
+bool ImGui_ImplSDLRenderer2_CreateFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+
+    // Build texture atlas
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
+
+    // Upload texture to graphics system
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    bd->FontTexture = SDL_CreateTexture(bd->SDLRenderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STATIC, width, height);
+    if (bd->FontTexture == nullptr)
+    {
+        SDL_Log("error creating texture");
+        return false;
+    }
+    SDL_UpdateTexture(bd->FontTexture, nullptr, pixels, 4 * width);
+    SDL_SetTextureBlendMode(bd->FontTexture, SDL_BLENDMODE_BLEND);
+    SDL_SetTextureScaleMode(bd->FontTexture, SDL_ScaleModeLinear);
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer2_DestroyFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer2_Data* bd = ImGui_ImplSDLRenderer2_GetBackendData();
+    if (bd->FontTexture)
+    {
+        io.Fonts->SetTexID(0);
+        SDL_DestroyTexture(bd->FontTexture);
+        bd->FontTexture = nullptr;
+    }
+}
+
+bool ImGui_ImplSDLRenderer2_CreateDeviceObjects()
+{
+    return ImGui_ImplSDLRenderer2_CreateFontsTexture();
+}
+
+void ImGui_ImplSDLRenderer2_DestroyDeviceObjects()
+{
+    ImGui_ImplSDLRenderer2_DestroyFontsTexture();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdlrenderer2.h

@@ -0,0 +1,39 @@
+// dear imgui: Renderer Backend for SDL_Renderer for SDL2
+// (Requires: SDL 2.0.17+)
+
+// Note how SDL_Renderer is an _optional_ component of SDL2.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer currently offers a limited graphic API to the end-user and
+// it might be difficult to step out of those boundaries.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#ifndef IMGUI_DISABLE
+#include "imgui.h"      // IMGUI_IMPL_API
+
+struct SDL_Renderer;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer2_Init(SDL_Renderer* renderer);
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_RenderDrawData(ImDrawData* draw_data);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer2_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer2_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_DestroyDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdlrenderer3.cpp

@@ -0,0 +1,261 @@
+// dear imgui: Renderer Backend for SDL_Renderer for SDL3
+// (Requires: SDL 3.0.0+)
+
+// Note how SDL_Renderer is an _optional_ component of SDL3.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer currently offers a limited graphic API to the end-user and
+// it might be difficult to step out of those boundaries.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+//  2023-05-30: Initial version.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_sdlrenderer3.h"
+#include <stdint.h>     // intptr_t
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"    // warning: implicit conversion changes signedness
+#endif
+
+// SDL
+#include <SDL3/SDL.h>
+#if !SDL_VERSION_ATLEAST(3,0,0)
+#error This backend requires SDL 3.0.0+
+#endif
+
+// SDL_Renderer data
+struct ImGui_ImplSDLRenderer3_Data
+{
+    SDL_Renderer*   SDLRenderer;
+    SDL_Texture*    FontTexture;
+    ImGui_ImplSDLRenderer3_Data() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplSDLRenderer3_Data* ImGui_ImplSDLRenderer3_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDLRenderer3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+bool ImGui_ImplSDLRenderer3_Init(SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+    IM_ASSERT(renderer != nullptr && "SDL_Renderer not initialized!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDLRenderer3_Data* bd = IM_NEW(ImGui_ImplSDLRenderer3_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_sdlrenderer3";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->SDLRenderer = renderer;
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer3_Shutdown()
+{
+    ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplSDLRenderer3_DestroyDeviceObjects();
+
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDLRenderer3_SetupRenderState()
+{
+	ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+
+	// Clear out any viewports and cliprect set by the user
+    // FIXME: Technically speaking there are lots of other things we could backup/setup/restore during our render process.
+	SDL_SetRenderViewport(bd->SDLRenderer, nullptr);
+	SDL_SetRenderClipRect(bd->SDLRenderer, nullptr);
+}
+
+void ImGui_ImplSDLRenderer3_NewFrame()
+{
+    ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDLRenderer3_Init()?");
+
+    if (!bd->FontTexture)
+        ImGui_ImplSDLRenderer3_CreateDeviceObjects();
+}
+
+void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data)
+{
+	ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+
+	// If there's a scale factor set by the user, use that instead
+    // If the user has specified a scale factor to SDL_Renderer already via SDL_RenderSetScale(), SDL will scale whatever we pass
+    // to SDL_RenderGeometryRaw() by that scale factor. In that case we don't want to be also scaling it ourselves here.
+    float rsx = 1.0f;
+	float rsy = 1.0f;
+	SDL_GetRenderScale(bd->SDLRenderer, &rsx, &rsy);
+    ImVec2 render_scale;
+	render_scale.x = (rsx == 1.0f) ? draw_data->FramebufferScale.x : 1.0f;
+	render_scale.y = (rsy == 1.0f) ? draw_data->FramebufferScale.y : 1.0f;
+
+	// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+	int fb_width = (int)(draw_data->DisplaySize.x * render_scale.x);
+	int fb_height = (int)(draw_data->DisplaySize.y * render_scale.y);
+	if (fb_width == 0 || fb_height == 0)
+		return;
+
+    // Backup SDL_Renderer state that will be modified to restore it afterwards
+    struct BackupSDLRendererState
+    {
+        SDL_Rect    Viewport;
+        bool        ClipEnabled;
+        SDL_Rect    ClipRect;
+    };
+    BackupSDLRendererState old = {};
+    old.ClipEnabled = SDL_RenderClipEnabled(bd->SDLRenderer) == SDL_TRUE;
+    SDL_GetRenderViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_GetRenderClipRect(bd->SDLRenderer, &old.ClipRect);
+
+	// Will project scissor/clipping rectangles into framebuffer space
+	ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
+	ImVec2 clip_scale = render_scale;
+
+    // Render command lists
+    ImGui_ImplSDLRenderer3_SetupRenderState();
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplSDLRenderer3_SetupRenderState();
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_min.x < 0.0f) { clip_min.x = 0.0f; }
+                if (clip_min.y < 0.0f) { clip_min.y = 0.0f; }
+                if (clip_max.x > (float)fb_width) { clip_max.x = (float)fb_width; }
+                if (clip_max.y > (float)fb_height) { clip_max.y = (float)fb_height; }
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                SDL_Rect r = { (int)(clip_min.x), (int)(clip_min.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y) };
+                SDL_SetRenderClipRect(bd->SDLRenderer, &r);
+
+                const float* xy = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, pos));
+                const float* uv = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, uv));
+#if SDL_VERSION_ATLEAST(2,0,19)
+                const SDL_Color* color = (const SDL_Color*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.19+
+#else
+                const int* color = (const int*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.17 and 2.0.18
+#endif
+
+                // Bind texture, Draw
+				SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID();
+                SDL_RenderGeometryRaw(bd->SDLRenderer, tex,
+                    xy, (int)sizeof(ImDrawVert),
+                    color, (int)sizeof(ImDrawVert),
+                    uv, (int)sizeof(ImDrawVert),
+                    cmd_list->VtxBuffer.Size - pcmd->VtxOffset,
+                    idx_buffer + pcmd->IdxOffset, pcmd->ElemCount, sizeof(ImDrawIdx));
+            }
+        }
+    }
+
+    // Restore modified SDL_Renderer state
+    SDL_SetRenderViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_SetRenderClipRect(bd->SDLRenderer, old.ClipEnabled ? &old.ClipRect : nullptr);
+}
+
+// Called by Init/NewFrame/Shutdown
+bool ImGui_ImplSDLRenderer3_CreateFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+
+    // Build texture atlas
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
+
+    // Upload texture to graphics system
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    bd->FontTexture = SDL_CreateTexture(bd->SDLRenderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STATIC, width, height);
+    if (bd->FontTexture == nullptr)
+    {
+        SDL_Log("error creating texture");
+        return false;
+    }
+    SDL_UpdateTexture(bd->FontTexture, nullptr, pixels, 4 * width);
+    SDL_SetTextureBlendMode(bd->FontTexture, SDL_BLENDMODE_BLEND);
+    SDL_SetTextureScaleMode(bd->FontTexture, SDL_SCALEMODE_LINEAR);
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer3_DestroyFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+    if (bd->FontTexture)
+    {
+        io.Fonts->SetTexID(0);
+        SDL_DestroyTexture(bd->FontTexture);
+        bd->FontTexture = nullptr;
+    }
+}
+
+bool ImGui_ImplSDLRenderer3_CreateDeviceObjects()
+{
+    return ImGui_ImplSDLRenderer3_CreateFontsTexture();
+}
+
+void ImGui_ImplSDLRenderer3_DestroyDeviceObjects()
+{
+    ImGui_ImplSDLRenderer3_DestroyFontsTexture();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_sdlrenderer3.h

@@ -0,0 +1,39 @@
+// dear imgui: Renderer Backend for SDL_Renderer for SDL3
+// (Requires: SDL 3.0.0+)
+
+// Note how SDL_Renderer is an _optional_ component of SDL3.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer currently offers a limited graphic API to the end-user and
+// it might be difficult to step out of those boundaries.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+struct SDL_Renderer;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer3_Init(SDL_Renderer* renderer);
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer3_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer3_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_DestroyDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_vulkan.h

@@ -0,0 +1,169 @@
+// dear imgui: Renderer Backend for Vulkan
+// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
+// See imgui_impl_vulkan.cpp file for details.
+
+// The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
+// IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// Important note to the reader who wish to integrate imgui_impl_vulkan.cpp/.h in their own engine/app.
+// - Common ImGui_ImplVulkan_XXX functions and structures are used to interface with imgui_impl_vulkan.cpp/.h.
+//   You will use those if you want to use this rendering backend in your engine/app.
+// - Helper ImGui_ImplVulkanH_XXX functions and structures are only used by this example (main.cpp) and by
+//   the backend itself (imgui_impl_vulkan.cpp), but should PROBABLY NOT be used by your own engine/app code.
+// Read comments in imgui_impl_vulkan.h.
+
+#pragma once
+#ifndef IMGUI_DISABLE
+#include "imgui.h"      // IMGUI_IMPL_API
+
+// [Configuration] in order to use a custom Vulkan function loader:
+// (1) You'll need to disable default Vulkan function prototypes.
+//     We provide a '#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES' convenience configuration flag.
+//     In order to make sure this is visible from the imgui_impl_vulkan.cpp compilation unit:
+//     - Add '#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES' in your imconfig.h file
+//     - Or as a compilation flag in your build system
+//     - Or uncomment here (not recommended because you'd be modifying imgui sources!)
+//     - Do not simply add it in a .cpp file!
+// (2) Call ImGui_ImplVulkan_LoadFunctions() before ImGui_ImplVulkan_Init() with your custom function.
+// If you have no idea what this is, leave it alone!
+//#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES
+
+// Vulkan includes
+#if defined(IMGUI_IMPL_VULKAN_NO_PROTOTYPES) && !defined(VK_NO_PROTOTYPES)
+#define VK_NO_PROTOTYPES
+#endif
+#include <vulkan/vulkan.h>
+
+// Initialization data, for ImGui_ImplVulkan_Init()
+// [Please zero-clear before use!]
+struct ImGui_ImplVulkan_InitInfo
+{
+    VkInstance                      Instance;
+    VkPhysicalDevice                PhysicalDevice;
+    VkDevice                        Device;
+    uint32_t                        QueueFamily;
+    VkQueue                         Queue;
+    VkPipelineCache                 PipelineCache;
+    VkDescriptorPool                DescriptorPool;
+    uint32_t                        Subpass;
+    uint32_t                        MinImageCount;          // >= 2
+    uint32_t                        ImageCount;             // >= MinImageCount
+    VkSampleCountFlagBits           MSAASamples;            // >= VK_SAMPLE_COUNT_1_BIT (0 -> default to VK_SAMPLE_COUNT_1_BIT)
+
+    // Dynamic Rendering (Optional)
+    bool                            UseDynamicRendering;    // Need to explicitly enable VK_KHR_dynamic_rendering extension to use this, even for Vulkan 1.3.
+    VkFormat                        ColorAttachmentFormat;  // Required for dynamic rendering
+
+    // Allocation, Debugging
+    const VkAllocationCallbacks*    Allocator;
+    void                            (*CheckVkResultFn)(VkResult err);
+};
+
+// Called by user code
+IMGUI_IMPL_API bool         ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info, VkRenderPass render_pass);
+IMGUI_IMPL_API void         ImGui_ImplVulkan_Shutdown();
+IMGUI_IMPL_API void         ImGui_ImplVulkan_NewFrame();
+IMGUI_IMPL_API void         ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer command_buffer, VkPipeline pipeline = VK_NULL_HANDLE);
+IMGUI_IMPL_API bool         ImGui_ImplVulkan_CreateFontsTexture(VkCommandBuffer command_buffer);
+IMGUI_IMPL_API void         ImGui_ImplVulkan_DestroyFontUploadObjects();
+IMGUI_IMPL_API void         ImGui_ImplVulkan_SetMinImageCount(uint32_t min_image_count); // To override MinImageCount after initialization (e.g. if swap chain is recreated)
+
+// Register a texture (VkDescriptorSet == ImTextureID)
+// FIXME: This is experimental in the sense that we are unsure how to best design/tackle this problem
+// Please post to https://github.com/ocornut/imgui/pull/914 if you have suggestions.
+IMGUI_IMPL_API VkDescriptorSet ImGui_ImplVulkan_AddTexture(VkSampler sampler, VkImageView image_view, VkImageLayout image_layout);
+IMGUI_IMPL_API void            ImGui_ImplVulkan_RemoveTexture(VkDescriptorSet descriptor_set);
+
+// Optional: load Vulkan functions with a custom function loader
+// This is only useful with IMGUI_IMPL_VULKAN_NO_PROTOTYPES / VK_NO_PROTOTYPES
+IMGUI_IMPL_API bool         ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const char* function_name, void* user_data), void* user_data = nullptr);
+
+//-------------------------------------------------------------------------
+// Internal / Miscellaneous Vulkan Helpers
+// (Used by example's main.cpp. Used by multi-viewport features. PROBABLY NOT used by your own engine/app.)
+//-------------------------------------------------------------------------
+// You probably do NOT need to use or care about those functions.
+// Those functions only exist because:
+//   1) they facilitate the readability and maintenance of the multiple main.cpp examples files.
+//   2) the multi-viewport / platform window implementation needs them internally.
+// Generally we avoid exposing any kind of superfluous high-level helpers in the bindings,
+// but it is too much code to duplicate everywhere so we exceptionally expose them.
+//
+// Your engine/app will likely _already_ have code to setup all that stuff (swap chain, render pass, frame buffers, etc.).
+// You may read this code to learn about Vulkan, but it is recommended you use you own custom tailored code to do equivalent work.
+// (The ImGui_ImplVulkanH_XXX functions do not interact with any of the state used by the regular ImGui_ImplVulkan_XXX functions)
+//-------------------------------------------------------------------------
+
+struct ImGui_ImplVulkanH_Frame;
+struct ImGui_ImplVulkanH_Window;
+
+// Helpers
+IMGUI_IMPL_API void                 ImGui_ImplVulkanH_CreateOrResizeWindow(VkInstance instance, VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wnd, uint32_t queue_family, const VkAllocationCallbacks* allocator, int w, int h, uint32_t min_image_count);
+IMGUI_IMPL_API void                 ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui_ImplVulkanH_Window* wnd, const VkAllocationCallbacks* allocator);
+IMGUI_IMPL_API VkSurfaceFormatKHR   ImGui_ImplVulkanH_SelectSurfaceFormat(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkFormat* request_formats, int request_formats_count, VkColorSpaceKHR request_color_space);
+IMGUI_IMPL_API VkPresentModeKHR     ImGui_ImplVulkanH_SelectPresentMode(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkPresentModeKHR* request_modes, int request_modes_count);
+IMGUI_IMPL_API int                  ImGui_ImplVulkanH_GetMinImageCountFromPresentMode(VkPresentModeKHR present_mode);
+
+// Helper structure to hold the data needed by one rendering frame
+// (Used by example's main.cpp. Used by multi-viewport features. Probably NOT used by your own engine/app.)
+// [Please zero-clear before use!]
+struct ImGui_ImplVulkanH_Frame
+{
+    VkCommandPool       CommandPool;
+    VkCommandBuffer     CommandBuffer;
+    VkFence             Fence;
+    VkImage             Backbuffer;
+    VkImageView         BackbufferView;
+    VkFramebuffer       Framebuffer;
+};
+
+struct ImGui_ImplVulkanH_FrameSemaphores
+{
+    VkSemaphore         ImageAcquiredSemaphore;
+    VkSemaphore         RenderCompleteSemaphore;
+};
+
+// Helper structure to hold the data needed by one rendering context into one OS window
+// (Used by example's main.cpp. Used by multi-viewport features. Probably NOT used by your own engine/app.)
+struct ImGui_ImplVulkanH_Window
+{
+    int                 Width;
+    int                 Height;
+    VkSwapchainKHR      Swapchain;
+    VkSurfaceKHR        Surface;
+    VkSurfaceFormatKHR  SurfaceFormat;
+    VkPresentModeKHR    PresentMode;
+    VkRenderPass        RenderPass;
+    VkPipeline          Pipeline;               // The window pipeline may uses a different VkRenderPass than the one passed in ImGui_ImplVulkan_InitInfo
+    bool                UseDynamicRendering;
+    bool                ClearEnable;
+    VkClearValue        ClearValue;
+    uint32_t            FrameIndex;             // Current frame being rendered to (0 <= FrameIndex < FrameInFlightCount)
+    uint32_t            ImageCount;             // Number of simultaneous in-flight frames (returned by vkGetSwapchainImagesKHR, usually derived from min_image_count)
+    uint32_t            SemaphoreIndex;         // Current set of swapchain wait semaphores we're using (needs to be distinct from per frame data)
+    ImGui_ImplVulkanH_Frame*            Frames;
+    ImGui_ImplVulkanH_FrameSemaphores*  FrameSemaphores;
+
+    ImGui_ImplVulkanH_Window()
+    {
+        memset((void*)this, 0, sizeof(*this));
+        PresentMode = (VkPresentModeKHR)~0;     // Ensure we get an error if user doesn't set this.
+        ClearEnable = true;
+    }
+};
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_wgpu.cpp

@@ -0,0 +1,772 @@
+// dear imgui: Renderer for WebGPU
+// This needs to be used along with a Platform Binding (e.g. GLFW)
+// (Please note that WebGPU is currently experimental, will not run on non-beta browsers, and may break.)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-07-13: Use WGPUShaderModuleWGSLDescriptor's code instead of source. use WGPUMipmapFilterMode_Linear instead of WGPUFilterMode_Linear. (#6602)
+//  2023-04-11: Align buffer sizes. Use WGSL shaders instead of precompiled SPIR-V.
+//  2023-04-11: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2023-01-25: Revert automatic pipeline layout generation (see https://github.com/gpuweb/gpuweb/issues/2470)
+//  2022-11-24: Fixed validation error with default depth buffer settings.
+//  2022-11-10: Fixed rendering when a depth buffer is enabled. Added 'WGPUTextureFormat depth_format' parameter to ImGui_ImplWGPU_Init().
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-11-29: Passing explicit buffer sizes to wgpuRenderPassEncoderSetVertexBuffer()/wgpuRenderPassEncoderSetIndexBuffer().
+//  2021-08-24: Fixed for latest specs.
+//  2021-05-24: Add support for draw_data->FramebufferScale.
+//  2021-05-19: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
+//  2021-05-16: Update to latest WebGPU specs (compatible with Emscripten 2.0.20 and Chrome Canary 92).
+//  2021-02-18: Change blending equation to preserve alpha in output buffer.
+//  2021-01-28: Initial version.
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_wgpu.h"
+#include <limits.h>
+#include <webgpu/webgpu.h>
+
+// Dear ImGui prototypes from imgui_internal.h
+extern ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed = 0);
+#define MEMALIGN(_SIZE,_ALIGN)        (((_SIZE) + ((_ALIGN) - 1)) & ~((_ALIGN) - 1))    // Memory align (copied from IM_ALIGN() macro).
+
+// WebGPU data
+struct RenderResources
+{
+    WGPUTexture         FontTexture = nullptr;          // Font texture
+    WGPUTextureView     FontTextureView = nullptr;      // Texture view for font texture
+    WGPUSampler         Sampler = nullptr;              // Sampler for the font texture
+    WGPUBuffer          Uniforms = nullptr;             // Shader uniforms
+    WGPUBindGroup       CommonBindGroup = nullptr;      // Resources bind-group to bind the common resources to pipeline
+    ImGuiStorage        ImageBindGroups;                // Resources bind-group to bind the font/image resources to pipeline (this is a key->value map)
+    WGPUBindGroup       ImageBindGroup = nullptr;       // Default font-resource of Dear ImGui
+    WGPUBindGroupLayout ImageBindGroupLayout = nullptr; // Cache layout used for the image bind group. Avoids allocating unnecessary JS objects when working with WebASM
+};
+
+struct FrameResources
+{
+    WGPUBuffer  IndexBuffer;
+    WGPUBuffer  VertexBuffer;
+    ImDrawIdx*  IndexBufferHost;
+    ImDrawVert* VertexBufferHost;
+    int         IndexBufferSize;
+    int         VertexBufferSize;
+};
+
+struct Uniforms
+{
+    float MVP[4][4];
+    float Gamma;
+};
+
+struct ImGui_ImplWGPU_Data
+{
+    WGPUDevice          wgpuDevice = nullptr;
+    WGPUQueue           defaultQueue = nullptr;
+    WGPUTextureFormat   renderTargetFormat = WGPUTextureFormat_Undefined;
+    WGPUTextureFormat   depthStencilFormat = WGPUTextureFormat_Undefined;
+    WGPURenderPipeline  pipelineState = nullptr;
+
+    RenderResources     renderResources;
+    FrameResources*     pFrameResources = nullptr;
+    unsigned int        numFramesInFlight = 0;
+    unsigned int        frameIndex = UINT_MAX;
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplWGPU_Data* ImGui_ImplWGPU_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplWGPU_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+//-----------------------------------------------------------------------------
+// SHADERS
+//-----------------------------------------------------------------------------
+
+static const char __shader_vert_wgsl[] = R"(
+struct VertexInput {
+    @location(0) position: vec2<f32>,
+    @location(1) uv: vec2<f32>,
+    @location(2) color: vec4<f32>,
+};
+
+struct VertexOutput {
+    @builtin(position) position: vec4<f32>,
+    @location(0) color: vec4<f32>,
+    @location(1) uv: vec2<f32>,
+};
+
+struct Uniforms {
+    mvp: mat4x4<f32>,
+    gamma: f32,
+};
+
+@group(0) @binding(0) var<uniform> uniforms: Uniforms;
+
+@vertex
+fn main(in: VertexInput) -> VertexOutput {
+    var out: VertexOutput;
+    out.position = uniforms.mvp * vec4<f32>(in.position, 0.0, 1.0);
+    out.color = in.color;
+    out.uv = in.uv;
+    return out;
+}
+)";
+
+static const char __shader_frag_wgsl[] = R"(
+struct VertexOutput {
+    @builtin(position) position: vec4<f32>,
+    @location(0) color: vec4<f32>,
+    @location(1) uv: vec2<f32>,
+};
+
+struct Uniforms {
+    mvp: mat4x4<f32>,
+    gamma: f32,
+};
+
+@group(0) @binding(0) var<uniform> uniforms: Uniforms;
+@group(0) @binding(1) var s: sampler;
+@group(1) @binding(0) var t: texture_2d<f32>;
+
+@fragment
+fn main(in: VertexOutput) -> @location(0) vec4<f32> {
+    let color = in.color * textureSample(t, s, in.uv);
+    let corrected_color = pow(color.rgb, vec3<f32>(uniforms.gamma));
+    return vec4<f32>(corrected_color, color.a);
+}
+)";
+
+static void SafeRelease(ImDrawIdx*& res)
+{
+    if (res)
+        delete[] res;
+    res = nullptr;
+}
+static void SafeRelease(ImDrawVert*& res)
+{
+    if (res)
+        delete[] res;
+    res = nullptr;
+}
+static void SafeRelease(WGPUBindGroupLayout& res)
+{
+    if (res)
+        wgpuBindGroupLayoutRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUBindGroup& res)
+{
+    if (res)
+        wgpuBindGroupRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUBuffer& res)
+{
+    if (res)
+        wgpuBufferRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPURenderPipeline& res)
+{
+    if (res)
+        wgpuRenderPipelineRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUSampler& res)
+{
+    if (res)
+        wgpuSamplerRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUShaderModule& res)
+{
+    if (res)
+        wgpuShaderModuleRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUTextureView& res)
+{
+    if (res)
+        wgpuTextureViewRelease(res);
+    res = nullptr;
+}
+static void SafeRelease(WGPUTexture& res)
+{
+    if (res)
+        wgpuTextureRelease(res);
+    res = nullptr;
+}
+
+static void SafeRelease(RenderResources& res)
+{
+    SafeRelease(res.FontTexture);
+    SafeRelease(res.FontTextureView);
+    SafeRelease(res.Sampler);
+    SafeRelease(res.Uniforms);
+    SafeRelease(res.CommonBindGroup);
+    SafeRelease(res.ImageBindGroup);
+    SafeRelease(res.ImageBindGroupLayout);
+};
+
+static void SafeRelease(FrameResources& res)
+{
+    SafeRelease(res.IndexBuffer);
+    SafeRelease(res.VertexBuffer);
+    SafeRelease(res.IndexBufferHost);
+    SafeRelease(res.VertexBufferHost);
+}
+
+static WGPUProgrammableStageDescriptor ImGui_ImplWGPU_CreateShaderModule(const char* wgsl_source)
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+
+    WGPUShaderModuleWGSLDescriptor wgsl_desc = {};
+    wgsl_desc.chain.sType = WGPUSType_ShaderModuleWGSLDescriptor;
+    wgsl_desc.code = wgsl_source;
+
+    WGPUShaderModuleDescriptor desc = {};
+    desc.nextInChain = reinterpret_cast<WGPUChainedStruct*>(&wgsl_desc);
+
+    WGPUProgrammableStageDescriptor stage_desc = {};
+    stage_desc.module = wgpuDeviceCreateShaderModule(bd->wgpuDevice, &desc);
+    stage_desc.entryPoint = "main";
+    return stage_desc;
+}
+
+static WGPUBindGroup ImGui_ImplWGPU_CreateImageBindGroup(WGPUBindGroupLayout layout, WGPUTextureView texture)
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    WGPUBindGroupEntry image_bg_entries[] = { { nullptr, 0, 0, 0, 0, 0, texture } };
+
+    WGPUBindGroupDescriptor image_bg_descriptor = {};
+    image_bg_descriptor.layout = layout;
+    image_bg_descriptor.entryCount = sizeof(image_bg_entries) / sizeof(WGPUBindGroupEntry);
+    image_bg_descriptor.entries = image_bg_entries;
+    return wgpuDeviceCreateBindGroup(bd->wgpuDevice, &image_bg_descriptor);
+}
+
+static void ImGui_ImplWGPU_SetupRenderState(ImDrawData* draw_data, WGPURenderPassEncoder ctx, FrameResources* fr)
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+
+    // Setup orthographic projection matrix into our constant buffer
+    // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
+    {
+        float L = draw_data->DisplayPos.x;
+        float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
+        float T = draw_data->DisplayPos.y;
+        float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
+        float mvp[4][4] =
+        {
+            { 2.0f/(R-L),   0.0f,           0.0f,       0.0f },
+            { 0.0f,         2.0f/(T-B),     0.0f,       0.0f },
+            { 0.0f,         0.0f,           0.5f,       0.0f },
+            { (R+L)/(L-R),  (T+B)/(B-T),    0.5f,       1.0f },
+        };
+        wgpuQueueWriteBuffer(bd->defaultQueue, bd->renderResources.Uniforms, offsetof(Uniforms, MVP), mvp, sizeof(Uniforms::MVP));
+        float gamma;
+        switch (bd->renderTargetFormat)
+        {
+        case WGPUTextureFormat_ASTC10x10UnormSrgb:
+        case WGPUTextureFormat_ASTC10x5UnormSrgb:
+        case WGPUTextureFormat_ASTC10x6UnormSrgb:
+        case WGPUTextureFormat_ASTC10x8UnormSrgb:
+        case WGPUTextureFormat_ASTC12x10UnormSrgb:
+        case WGPUTextureFormat_ASTC12x12UnormSrgb:
+        case WGPUTextureFormat_ASTC4x4UnormSrgb:
+        case WGPUTextureFormat_ASTC5x5UnormSrgb:
+        case WGPUTextureFormat_ASTC6x5UnormSrgb:
+        case WGPUTextureFormat_ASTC6x6UnormSrgb:
+        case WGPUTextureFormat_ASTC8x5UnormSrgb:
+        case WGPUTextureFormat_ASTC8x6UnormSrgb:
+        case WGPUTextureFormat_ASTC8x8UnormSrgb:
+        case WGPUTextureFormat_BC1RGBAUnormSrgb:
+        case WGPUTextureFormat_BC2RGBAUnormSrgb:
+        case WGPUTextureFormat_BC3RGBAUnormSrgb:
+        case WGPUTextureFormat_BC7RGBAUnormSrgb:
+        case WGPUTextureFormat_BGRA8UnormSrgb:
+        case WGPUTextureFormat_ETC2RGB8A1UnormSrgb:
+        case WGPUTextureFormat_ETC2RGB8UnormSrgb:
+        case WGPUTextureFormat_ETC2RGBA8UnormSrgb:
+        case WGPUTextureFormat_RGBA8UnormSrgb:
+            gamma = 2.2f;
+            break;
+        default:
+            gamma = 1.0f;
+        }
+        wgpuQueueWriteBuffer(bd->defaultQueue, bd->renderResources.Uniforms, offsetof(Uniforms, Gamma), &gamma, sizeof(Uniforms::Gamma));
+    }
+
+    // Setup viewport
+    wgpuRenderPassEncoderSetViewport(ctx, 0, 0, draw_data->FramebufferScale.x * draw_data->DisplaySize.x, draw_data->FramebufferScale.y * draw_data->DisplaySize.y, 0, 1);
+
+    // Bind shader and vertex buffers
+    wgpuRenderPassEncoderSetVertexBuffer(ctx, 0, fr->VertexBuffer, 0, fr->VertexBufferSize * sizeof(ImDrawVert));
+    wgpuRenderPassEncoderSetIndexBuffer(ctx, fr->IndexBuffer, sizeof(ImDrawIdx) == 2 ? WGPUIndexFormat_Uint16 : WGPUIndexFormat_Uint32, 0, fr->IndexBufferSize * sizeof(ImDrawIdx));
+    wgpuRenderPassEncoderSetPipeline(ctx, bd->pipelineState);
+    wgpuRenderPassEncoderSetBindGroup(ctx, 0, bd->renderResources.CommonBindGroup, 0, nullptr);
+
+    // Setup blend factor
+    WGPUColor blend_color = { 0.f, 0.f, 0.f, 0.f };
+    wgpuRenderPassEncoderSetBlendConstant(ctx, &blend_color);
+}
+
+// Render function
+// (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop)
+void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder pass_encoder)
+{
+    // Avoid rendering when minimized
+    if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
+        return;
+
+    // FIXME: Assuming that this only gets called once per frame!
+    // If not, we can't just re-allocate the IB or VB, we'll have to do a proper allocator.
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    bd->frameIndex = bd->frameIndex + 1;
+    FrameResources* fr = &bd->pFrameResources[bd->frameIndex % bd->numFramesInFlight];
+
+    // Create and grow vertex/index buffers if needed
+    if (fr->VertexBuffer == nullptr || fr->VertexBufferSize < draw_data->TotalVtxCount)
+    {
+        if (fr->VertexBuffer)
+        {
+            wgpuBufferDestroy(fr->VertexBuffer);
+            wgpuBufferRelease(fr->VertexBuffer);
+        }
+        SafeRelease(fr->VertexBufferHost);
+        fr->VertexBufferSize = draw_data->TotalVtxCount + 5000;
+
+        WGPUBufferDescriptor vb_desc =
+        {
+            nullptr,
+            "Dear ImGui Vertex buffer",
+            WGPUBufferUsage_CopyDst | WGPUBufferUsage_Vertex,
+            MEMALIGN(fr->VertexBufferSize * sizeof(ImDrawVert), 4),
+            false
+        };
+        fr->VertexBuffer = wgpuDeviceCreateBuffer(bd->wgpuDevice, &vb_desc);
+        if (!fr->VertexBuffer)
+            return;
+
+        fr->VertexBufferHost = new ImDrawVert[fr->VertexBufferSize];
+    }
+    if (fr->IndexBuffer == nullptr || fr->IndexBufferSize < draw_data->TotalIdxCount)
+    {
+        if (fr->IndexBuffer)
+        {
+            wgpuBufferDestroy(fr->IndexBuffer);
+            wgpuBufferRelease(fr->IndexBuffer);
+        }
+        SafeRelease(fr->IndexBufferHost);
+        fr->IndexBufferSize = draw_data->TotalIdxCount + 10000;
+
+        WGPUBufferDescriptor ib_desc =
+        {
+            nullptr,
+            "Dear ImGui Index buffer",
+            WGPUBufferUsage_CopyDst | WGPUBufferUsage_Index,
+            MEMALIGN(fr->IndexBufferSize * sizeof(ImDrawIdx), 4),
+            false
+        };
+        fr->IndexBuffer = wgpuDeviceCreateBuffer(bd->wgpuDevice, &ib_desc);
+        if (!fr->IndexBuffer)
+            return;
+
+        fr->IndexBufferHost = new ImDrawIdx[fr->IndexBufferSize];
+    }
+
+    // Upload vertex/index data into a single contiguous GPU buffer
+    ImDrawVert* vtx_dst = (ImDrawVert*)fr->VertexBufferHost;
+    ImDrawIdx* idx_dst = (ImDrawIdx*)fr->IndexBufferHost;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += cmd_list->VtxBuffer.Size;
+        idx_dst += cmd_list->IdxBuffer.Size;
+    }
+    int64_t vb_write_size = MEMALIGN((char*)vtx_dst - (char*)fr->VertexBufferHost, 4);
+    int64_t ib_write_size = MEMALIGN((char*)idx_dst - (char*)fr->IndexBufferHost, 4);
+    wgpuQueueWriteBuffer(bd->defaultQueue, fr->VertexBuffer, 0, fr->VertexBufferHost, vb_write_size);
+    wgpuQueueWriteBuffer(bd->defaultQueue, fr->IndexBuffer,  0, fr->IndexBufferHost,  ib_write_size);
+
+    // Setup desired render state
+    ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr);
+
+    // Render command lists
+    // (Because we merged all buffers into a single one, we maintain our own offset into them)
+    int global_vtx_offset = 0;
+    int global_idx_offset = 0;
+    ImVec2 clip_scale = draw_data->FramebufferScale;
+    ImVec2 clip_off = draw_data->DisplayPos;
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback != nullptr)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr);
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Bind custom texture
+                ImTextureID tex_id = pcmd->GetTexID();
+                ImGuiID tex_id_hash = ImHashData(&tex_id, sizeof(tex_id));
+                auto bind_group = bd->renderResources.ImageBindGroups.GetVoidPtr(tex_id_hash);
+                if (bind_group)
+                {
+                    wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, (WGPUBindGroup)bind_group, 0, nullptr);
+                }
+                else
+                {
+                    WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(bd->renderResources.ImageBindGroupLayout, (WGPUTextureView)tex_id);
+                    bd->renderResources.ImageBindGroups.SetVoidPtr(tex_id_hash, image_bind_group);
+                    wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, image_bind_group, 0, nullptr);
+                }
+
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                // Apply scissor/clipping rectangle, Draw
+                wgpuRenderPassEncoderSetScissorRect(pass_encoder, (uint32_t)clip_min.x, (uint32_t)clip_min.y, (uint32_t)(clip_max.x - clip_min.x), (uint32_t)(clip_max.y - clip_min.y));
+                wgpuRenderPassEncoderDrawIndexed(pass_encoder, pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
+            }
+        }
+        global_idx_offset += cmd_list->IdxBuffer.Size;
+        global_vtx_offset += cmd_list->VtxBuffer.Size;
+    }
+}
+
+static void ImGui_ImplWGPU_CreateFontsTexture()
+{
+    // Build texture atlas
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    unsigned char* pixels;
+    int width, height, size_pp;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &size_pp);
+
+    // Upload texture to graphics system
+    {
+        WGPUTextureDescriptor tex_desc = {};
+        tex_desc.label = "Dear ImGui Font Texture";
+        tex_desc.dimension = WGPUTextureDimension_2D;
+        tex_desc.size.width = width;
+        tex_desc.size.height = height;
+        tex_desc.size.depthOrArrayLayers = 1;
+        tex_desc.sampleCount = 1;
+        tex_desc.format = WGPUTextureFormat_RGBA8Unorm;
+        tex_desc.mipLevelCount = 1;
+        tex_desc.usage = WGPUTextureUsage_CopyDst | WGPUTextureUsage_TextureBinding;
+        bd->renderResources.FontTexture = wgpuDeviceCreateTexture(bd->wgpuDevice, &tex_desc);
+
+        WGPUTextureViewDescriptor tex_view_desc = {};
+        tex_view_desc.format = WGPUTextureFormat_RGBA8Unorm;
+        tex_view_desc.dimension = WGPUTextureViewDimension_2D;
+        tex_view_desc.baseMipLevel = 0;
+        tex_view_desc.mipLevelCount = 1;
+        tex_view_desc.baseArrayLayer = 0;
+        tex_view_desc.arrayLayerCount = 1;
+        tex_view_desc.aspect = WGPUTextureAspect_All;
+        bd->renderResources.FontTextureView = wgpuTextureCreateView(bd->renderResources.FontTexture, &tex_view_desc);
+    }
+
+    // Upload texture data
+    {
+        WGPUImageCopyTexture dst_view = {};
+        dst_view.texture = bd->renderResources.FontTexture;
+        dst_view.mipLevel = 0;
+        dst_view.origin = { 0, 0, 0 };
+        dst_view.aspect = WGPUTextureAspect_All;
+        WGPUTextureDataLayout layout = {};
+        layout.offset = 0;
+        layout.bytesPerRow = width * size_pp;
+        layout.rowsPerImage = height;
+        WGPUExtent3D size = { (uint32_t)width, (uint32_t)height, 1 };
+        wgpuQueueWriteTexture(bd->defaultQueue, &dst_view, pixels, (uint32_t)(width * size_pp * height), &layout, &size);
+    }
+
+    // Create the associated sampler
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    {
+        WGPUSamplerDescriptor sampler_desc = {};
+        sampler_desc.minFilter = WGPUFilterMode_Linear;
+        sampler_desc.magFilter = WGPUFilterMode_Linear;
+        sampler_desc.mipmapFilter = WGPUMipmapFilterMode_Linear;
+        sampler_desc.addressModeU = WGPUAddressMode_Repeat;
+        sampler_desc.addressModeV = WGPUAddressMode_Repeat;
+        sampler_desc.addressModeW = WGPUAddressMode_Repeat;
+        sampler_desc.maxAnisotropy = 1;
+        bd->renderResources.Sampler = wgpuDeviceCreateSampler(bd->wgpuDevice, &sampler_desc);
+    }
+
+    // Store our identifier
+    static_assert(sizeof(ImTextureID) >= sizeof(bd->renderResources.FontTexture), "Can't pack descriptor handle into TexID, 32-bit not supported yet.");
+    io.Fonts->SetTexID((ImTextureID)bd->renderResources.FontTextureView);
+}
+
+static void ImGui_ImplWGPU_CreateUniformBuffer()
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    WGPUBufferDescriptor ub_desc =
+    {
+        nullptr,
+        "Dear ImGui Uniform buffer",
+        WGPUBufferUsage_CopyDst | WGPUBufferUsage_Uniform,
+        MEMALIGN(sizeof(Uniforms), 16),
+        false
+    };
+    bd->renderResources.Uniforms = wgpuDeviceCreateBuffer(bd->wgpuDevice, &ub_desc);
+}
+
+bool ImGui_ImplWGPU_CreateDeviceObjects()
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    if (!bd->wgpuDevice)
+        return false;
+    if (bd->pipelineState)
+        ImGui_ImplWGPU_InvalidateDeviceObjects();
+
+    // Create render pipeline
+    WGPURenderPipelineDescriptor graphics_pipeline_desc = {};
+    graphics_pipeline_desc.primitive.topology = WGPUPrimitiveTopology_TriangleList;
+    graphics_pipeline_desc.primitive.stripIndexFormat = WGPUIndexFormat_Undefined;
+    graphics_pipeline_desc.primitive.frontFace = WGPUFrontFace_CW;
+    graphics_pipeline_desc.primitive.cullMode = WGPUCullMode_None;
+    graphics_pipeline_desc.multisample.count = 1;
+    graphics_pipeline_desc.multisample.mask = UINT_MAX;
+    graphics_pipeline_desc.multisample.alphaToCoverageEnabled = false;
+
+    // Bind group layouts
+    WGPUBindGroupLayoutEntry common_bg_layout_entries[2] = {};
+    common_bg_layout_entries[0].binding = 0;
+    common_bg_layout_entries[0].visibility = WGPUShaderStage_Vertex | WGPUShaderStage_Fragment;
+    common_bg_layout_entries[0].buffer.type = WGPUBufferBindingType_Uniform;
+    common_bg_layout_entries[1].binding = 1;
+    common_bg_layout_entries[1].visibility = WGPUShaderStage_Fragment;
+    common_bg_layout_entries[1].sampler.type = WGPUSamplerBindingType_Filtering;
+
+    WGPUBindGroupLayoutEntry image_bg_layout_entries[1] = {};
+    image_bg_layout_entries[0].binding = 0;
+    image_bg_layout_entries[0].visibility = WGPUShaderStage_Fragment;
+    image_bg_layout_entries[0].texture.sampleType = WGPUTextureSampleType_Float;
+    image_bg_layout_entries[0].texture.viewDimension = WGPUTextureViewDimension_2D;
+
+    WGPUBindGroupLayoutDescriptor common_bg_layout_desc = {};
+    common_bg_layout_desc.entryCount = 2;
+    common_bg_layout_desc.entries = common_bg_layout_entries;
+
+    WGPUBindGroupLayoutDescriptor image_bg_layout_desc = {};
+    image_bg_layout_desc.entryCount = 1;
+    image_bg_layout_desc.entries = image_bg_layout_entries;
+
+    WGPUBindGroupLayout bg_layouts[2];
+    bg_layouts[0] = wgpuDeviceCreateBindGroupLayout(bd->wgpuDevice, &common_bg_layout_desc);
+    bg_layouts[1] = wgpuDeviceCreateBindGroupLayout(bd->wgpuDevice, &image_bg_layout_desc);
+
+    WGPUPipelineLayoutDescriptor layout_desc = {};
+    layout_desc.bindGroupLayoutCount = 2;
+    layout_desc.bindGroupLayouts = bg_layouts;
+    graphics_pipeline_desc.layout = wgpuDeviceCreatePipelineLayout(bd->wgpuDevice, &layout_desc);
+
+    // Create the vertex shader
+    WGPUProgrammableStageDescriptor vertex_shader_desc = ImGui_ImplWGPU_CreateShaderModule(__shader_vert_wgsl);
+    graphics_pipeline_desc.vertex.module = vertex_shader_desc.module;
+    graphics_pipeline_desc.vertex.entryPoint = vertex_shader_desc.entryPoint;
+
+    // Vertex input configuration
+    WGPUVertexAttribute attribute_desc[] =
+    {
+        { WGPUVertexFormat_Float32x2, (uint64_t)IM_OFFSETOF(ImDrawVert, pos), 0 },
+        { WGPUVertexFormat_Float32x2, (uint64_t)IM_OFFSETOF(ImDrawVert, uv),  1 },
+        { WGPUVertexFormat_Unorm8x4,  (uint64_t)IM_OFFSETOF(ImDrawVert, col), 2 },
+    };
+
+    WGPUVertexBufferLayout buffer_layouts[1];
+    buffer_layouts[0].arrayStride = sizeof(ImDrawVert);
+    buffer_layouts[0].stepMode = WGPUVertexStepMode_Vertex;
+    buffer_layouts[0].attributeCount = 3;
+    buffer_layouts[0].attributes = attribute_desc;
+
+    graphics_pipeline_desc.vertex.bufferCount = 1;
+    graphics_pipeline_desc.vertex.buffers = buffer_layouts;
+
+    // Create the pixel shader
+    WGPUProgrammableStageDescriptor pixel_shader_desc = ImGui_ImplWGPU_CreateShaderModule(__shader_frag_wgsl);
+
+    // Create the blending setup
+    WGPUBlendState blend_state = {};
+    blend_state.alpha.operation = WGPUBlendOperation_Add;
+    blend_state.alpha.srcFactor = WGPUBlendFactor_One;
+    blend_state.alpha.dstFactor = WGPUBlendFactor_OneMinusSrcAlpha;
+    blend_state.color.operation = WGPUBlendOperation_Add;
+    blend_state.color.srcFactor = WGPUBlendFactor_SrcAlpha;
+    blend_state.color.dstFactor = WGPUBlendFactor_OneMinusSrcAlpha;
+
+    WGPUColorTargetState color_state = {};
+    color_state.format = bd->renderTargetFormat;
+    color_state.blend = &blend_state;
+    color_state.writeMask = WGPUColorWriteMask_All;
+
+    WGPUFragmentState fragment_state = {};
+    fragment_state.module = pixel_shader_desc.module;
+    fragment_state.entryPoint = pixel_shader_desc.entryPoint;
+    fragment_state.targetCount = 1;
+    fragment_state.targets = &color_state;
+
+    graphics_pipeline_desc.fragment = &fragment_state;
+
+    // Create depth-stencil State
+    WGPUDepthStencilState depth_stencil_state = {};
+    depth_stencil_state.format = bd->depthStencilFormat;
+    depth_stencil_state.depthWriteEnabled = false;
+    depth_stencil_state.depthCompare = WGPUCompareFunction_Always;
+    depth_stencil_state.stencilFront.compare = WGPUCompareFunction_Always;
+    depth_stencil_state.stencilBack.compare = WGPUCompareFunction_Always;
+
+    // Configure disabled depth-stencil state
+    graphics_pipeline_desc.depthStencil = (bd->depthStencilFormat == WGPUTextureFormat_Undefined) ? nullptr :  &depth_stencil_state;
+
+    bd->pipelineState = wgpuDeviceCreateRenderPipeline(bd->wgpuDevice, &graphics_pipeline_desc);
+
+    ImGui_ImplWGPU_CreateFontsTexture();
+    ImGui_ImplWGPU_CreateUniformBuffer();
+
+    // Create resource bind group
+    WGPUBindGroupEntry common_bg_entries[] =
+    {
+        { nullptr, 0, bd->renderResources.Uniforms, 0, MEMALIGN(sizeof(Uniforms), 16), 0, 0 },
+        { nullptr, 1, 0, 0, 0, bd->renderResources.Sampler, 0 },
+    };
+
+    WGPUBindGroupDescriptor common_bg_descriptor = {};
+    common_bg_descriptor.layout = bg_layouts[0];
+    common_bg_descriptor.entryCount = sizeof(common_bg_entries) / sizeof(WGPUBindGroupEntry);
+    common_bg_descriptor.entries = common_bg_entries;
+    bd->renderResources.CommonBindGroup = wgpuDeviceCreateBindGroup(bd->wgpuDevice, &common_bg_descriptor);
+
+    WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(bg_layouts[1], bd->renderResources.FontTextureView);
+    bd->renderResources.ImageBindGroup = image_bind_group;
+    bd->renderResources.ImageBindGroupLayout = bg_layouts[1];
+    bd->renderResources.ImageBindGroups.SetVoidPtr(ImHashData(&bd->renderResources.FontTextureView, sizeof(ImTextureID)), image_bind_group);
+
+    SafeRelease(vertex_shader_desc.module);
+    SafeRelease(pixel_shader_desc.module);
+    SafeRelease(bg_layouts[0]);
+
+    return true;
+}
+
+void ImGui_ImplWGPU_InvalidateDeviceObjects()
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    if (!bd->wgpuDevice)
+        return;
+
+    SafeRelease(bd->pipelineState);
+    SafeRelease(bd->renderResources);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.Fonts->SetTexID(0); // We copied g_pFontTextureView to io.Fonts->TexID so let's clear that as well.
+
+    for (unsigned int i = 0; i < bd->numFramesInFlight; i++)
+        SafeRelease(bd->pFrameResources[i]);
+}
+
+bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextureFormat rt_format, WGPUTextureFormat depth_format)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplWGPU_Data* bd = IM_NEW(ImGui_ImplWGPU_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_webgpu";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->wgpuDevice = device;
+    bd->defaultQueue = wgpuDeviceGetQueue(bd->wgpuDevice);
+    bd->renderTargetFormat = rt_format;
+    bd->depthStencilFormat = depth_format;
+    bd->numFramesInFlight = num_frames_in_flight;
+    bd->frameIndex = UINT_MAX;
+
+    bd->renderResources.FontTexture = nullptr;
+    bd->renderResources.FontTextureView = nullptr;
+    bd->renderResources.Sampler = nullptr;
+    bd->renderResources.Uniforms = nullptr;
+    bd->renderResources.CommonBindGroup = nullptr;
+    bd->renderResources.ImageBindGroups.Data.reserve(100);
+    bd->renderResources.ImageBindGroup = nullptr;
+    bd->renderResources.ImageBindGroupLayout = nullptr;
+
+    // Create buffers with a default size (they will later be grown as needed)
+    bd->pFrameResources = new FrameResources[num_frames_in_flight];
+    for (int i = 0; i < num_frames_in_flight; i++)
+    {
+        FrameResources* fr = &bd->pFrameResources[i];
+        fr->IndexBuffer = nullptr;
+        fr->VertexBuffer = nullptr;
+        fr->IndexBufferHost = nullptr;
+        fr->VertexBufferHost = nullptr;
+        fr->IndexBufferSize = 10000;
+        fr->VertexBufferSize = 5000;
+    }
+
+    return true;
+}
+
+void ImGui_ImplWGPU_Shutdown()
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplWGPU_InvalidateDeviceObjects();
+    delete[] bd->pFrameResources;
+    bd->pFrameResources = nullptr;
+    wgpuQueueRelease(bd->defaultQueue);
+    bd->wgpuDevice = nullptr;
+    bd->numFramesInFlight = 0;
+    bd->frameIndex = UINT_MAX;
+
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    IM_DELETE(bd);
+}
+
+void ImGui_ImplWGPU_NewFrame()
+{
+    ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
+    if (!bd->pipelineState)
+        ImGui_ImplWGPU_CreateDeviceObjects();
+}
+
+//-----------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_wgpu.h

@@ -0,0 +1,32 @@
+// dear imgui: Renderer for WebGPU
+// This needs to be used along with a Platform Binding (e.g. GLFW)
+// (Please note that WebGPU is currently experimental, will not run on non-beta browsers, and may break.)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"          // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+#include <webgpu/webgpu.h>
+
+IMGUI_IMPL_API bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextureFormat rt_format, WGPUTextureFormat depth_format = WGPUTextureFormat_Undefined);
+IMGUI_IMPL_API void ImGui_ImplWGPU_Shutdown();
+IMGUI_IMPL_API void ImGui_ImplWGPU_NewFrame();
+IMGUI_IMPL_API void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder pass_encoder);
+
+// Use if you want to reset your rendering device without losing Dear ImGui state.
+IMGUI_IMPL_API void ImGui_ImplWGPU_InvalidateDeviceObjects();
+IMGUI_IMPL_API bool ImGui_ImplWGPU_CreateDeviceObjects();
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_win32.cpp

@@ -0,0 +1,888 @@
+// dear imgui: Platform Backend for Windows (standard windows API for 32-bits AND 64-bits applications)
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+
+// Implemented features:
+//  [X] Platform: Clipboard support (for Win32 this is actually part of core dear imgui)
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_win32.h"
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>
+#include <windowsx.h> // GET_X_LPARAM(), GET_Y_LPARAM()
+#include <tchar.h>
+#include <dwmapi.h>
+
+// Configuration flags to add in your imconfig.h file:
+//#define IMGUI_IMPL_WIN32_DISABLE_GAMEPAD              // Disable gamepad support. This was meaningful before <1.81 but we now load XInput dynamically so the option is now less relevant.
+
+// Using XInput for gamepad (will load DLL dynamically)
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+#include <xinput.h>
+typedef DWORD (WINAPI *PFN_XInputGetCapabilities)(DWORD, DWORD, XINPUT_CAPABILITIES*);
+typedef DWORD (WINAPI *PFN_XInputGetState)(DWORD, XINPUT_STATE*);
+#endif
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-09-25: Inputs: Synthesize key-down event on key-up for VK_SNAPSHOT / ImGuiKey_PrintScreen as Windows doesn't emit it (same behavior as GLFW/SDL).
+//  2023-09-07: Inputs: Added support for keyboard codepage conversion for when application is compiled in MBCS mode and using a non-Unicode window.
+//  2023-04-19: Added ImGui_ImplWin32_InitForOpenGL() to facilitate combining raw Win32/Winapi with OpenGL. (#3218)
+//  2023-04-04: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_TouchScreen/ImGuiMouseSource_Pen. (#2702)
+//  2023-02-15: Inputs: Use WM_NCMOUSEMOVE / WM_NCMOUSELEAVE to track mouse position over non-client area (e.g. OS decorations) when app is not focused. (#6045, #6162)
+//  2023-02-02: Inputs: Flipping WM_MOUSEHWHEEL (horizontal mouse-wheel) value to match other backends and offer consistent horizontal scrolling direction. (#4019, #6096, #1463)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-28: Inputs: Convert WM_CHAR values with MultiByteToWideChar() when window class was registered as MBCS (not Unicode).
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2021-01-20: Inputs: calling new io.AddKeyAnalogEvent() for gamepad support, instead of writing directly to io.NavInputs[].
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-17: Inputs: always update key mods next and before a key event (not in NewFrame) to fix input queue with very low framerates.
+//  2022-01-12: Inputs: Update mouse inputs using WM_MOUSEMOVE/WM_MOUSELEAVE + fallback to provide it when focused but not hovered/captured. More standard and will allow us to pass it to future input queue API.
+//  2022-01-12: Inputs: Maintain our own copy of MouseButtonsDown mask instead of using ImGui::IsAnyMouseDown() which will be obsoleted.
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-12-16: Inputs: Fill VK_LCONTROL/VK_RCONTROL/VK_LSHIFT/VK_RSHIFT/VK_LMENU/VK_RMENU for completeness.
+//  2021-08-17: Calling io.AddFocusEvent() on WM_SETFOCUS/WM_KILLFOCUS messages.
+//  2021-08-02: Inputs: Fixed keyboard modifiers being reported when host window doesn't have focus.
+//  2021-07-29: Inputs: MousePos is correctly reported when the host platform window is hovered but not focused (using TrackMouseEvent() to receive WM_MOUSELEAVE events).
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-06-08: Fixed ImGui_ImplWin32_EnableDpiAwareness() and ImGui_ImplWin32_GetDpiScaleForMonitor() to handle Windows 8.1/10 features without a manifest (per-monitor DPI, and properly calls SetProcessDpiAwareness() on 8.1).
+//  2021-03-23: Inputs: Clearing keyboard down array when losing focus (WM_KILLFOCUS).
+//  2021-02-18: Added ImGui_ImplWin32_EnableAlphaCompositing(). Non Visual Studio users will need to link with dwmapi.lib (MinGW/gcc: use -ldwmapi).
+//  2021-02-17: Fixed ImGui_ImplWin32_EnableDpiAwareness() attempting to get SetProcessDpiAwareness from shcore.dll on Windows 8 whereas it is only supported on Windows 8.1.
+//  2021-01-25: Inputs: Dynamically loading XInput DLL.
+//  2020-12-04: Misc: Fixed setting of io.DisplaySize to invalid/uninitialized data when after hwnd has been closed.
+//  2020-03-03: Inputs: Calling AddInputCharacterUTF16() to support surrogate pairs leading to codepoint >= 0x10000 (for more complete CJK inputs)
+//  2020-02-17: Added ImGui_ImplWin32_EnableDpiAwareness(), ImGui_ImplWin32_GetDpiScaleForHwnd(), ImGui_ImplWin32_GetDpiScaleForMonitor() helper functions.
+//  2020-01-14: Inputs: Added support for #define IMGUI_IMPL_WIN32_DISABLE_GAMEPAD/IMGUI_IMPL_WIN32_DISABLE_LINKING_XINPUT.
+//  2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
+//  2019-05-11: Inputs: Don't filter value from WM_CHAR before calling AddInputCharacter().
+//  2019-01-17: Misc: Using GetForegroundWindow()+IsChild() instead of GetActiveWindow() to be compatible with windows created in a different thread or parent.
+//  2019-01-17: Inputs: Added support for mouse buttons 4 and 5 via WM_XBUTTON* messages.
+//  2019-01-15: Inputs: Added support for XInput gamepads (if ImGuiConfigFlags_NavEnableGamepad is set by user application).
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-06-29: Inputs: Added support for the ImGuiMouseCursor_Hand cursor.
+//  2018-06-10: Inputs: Fixed handling of mouse wheel messages to support fine position messages (typically sent by track-pads).
+//  2018-06-08: Misc: Extracted imgui_impl_win32.cpp/.h away from the old combined DX9/DX10/DX11/DX12 examples.
+//  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors and ImGuiBackendFlags_HasSetMousePos flags + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-02-20: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value and WM_SETCURSOR message handling).
+//  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
+//  2018-02-06: Inputs: Honoring the io.WantSetMousePos by repositioning the mouse (when using navigation and ImGuiConfigFlags_NavMoveMouse is set).
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2018-01-20: Inputs: Added Horizontal Mouse Wheel support.
+//  2018-01-08: Inputs: Added mapping for ImGuiKey_Insert.
+//  2018-01-05: Inputs: Added WM_LBUTTONDBLCLK double-click handlers for window classes with the CS_DBLCLKS flag.
+//  2017-10-23: Inputs: Added WM_SYSKEYDOWN / WM_SYSKEYUP handlers so e.g. the VK_MENU key can be read.
+//  2017-10-23: Inputs: Using Win32 ::SetCapture/::GetCapture() to retrieve mouse positions outside the client area when dragging.
+//  2016-11-12: Inputs: Only call Win32 ::SetCursor(nullptr) when io.MouseDrawCursor is set.
+
+struct ImGui_ImplWin32_Data
+{
+    HWND                        hWnd;
+    HWND                        MouseHwnd;
+    int                         MouseTrackedArea;   // 0: not tracked, 1: client are, 2: non-client area
+    int                         MouseButtonsDown;
+    INT64                       Time;
+    INT64                       TicksPerSecond;
+    ImGuiMouseCursor            LastMouseCursor;
+    UINT32                      KeyboardCodePage;
+
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+    bool                        HasGamepad;
+    bool                        WantUpdateHasGamepad;
+    HMODULE                     XInputDLL;
+    PFN_XInputGetCapabilities   XInputGetCapabilities;
+    PFN_XInputGetState          XInputGetState;
+#endif
+
+    ImGui_ImplWin32_Data()      { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+// FIXME: some shared resources (mouse cursor shape, gamepad) are mishandled when using multi-context.
+static ImGui_ImplWin32_Data* ImGui_ImplWin32_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplWin32_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
+}
+
+// Functions
+static void ImGui_ImplWin32_UpdateKeyboardCodePage()
+{
+    // Retrieve keyboard code page, required for handling of non-Unicode Windows.
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    HKL keyboard_layout = ::GetKeyboardLayout(0);
+    LCID keyboard_lcid = MAKELCID(HIWORD(keyboard_layout), SORT_DEFAULT);
+    if (::GetLocaleInfoA(keyboard_lcid, (LOCALE_RETURN_NUMBER | LOCALE_IDEFAULTANSICODEPAGE), (LPSTR)&bd->KeyboardCodePage, sizeof(bd->KeyboardCodePage)) == 0)
+        bd->KeyboardCodePage = CP_ACP; // Fallback to default ANSI code page when fails.
+}
+
+static bool ImGui_ImplWin32_InitEx(void* hwnd, bool platform_has_own_dc)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+
+    INT64 perf_frequency, perf_counter;
+    if (!::QueryPerformanceFrequency((LARGE_INTEGER*)&perf_frequency))
+        return false;
+    if (!::QueryPerformanceCounter((LARGE_INTEGER*)&perf_counter))
+        return false;
+
+    // Setup backend capabilities flags
+    ImGui_ImplWin32_Data* bd = IM_NEW(ImGui_ImplWin32_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = "imgui_impl_win32";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;         // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+
+    bd->hWnd = (HWND)hwnd;
+    bd->TicksPerSecond = perf_frequency;
+    bd->Time = perf_counter;
+    bd->LastMouseCursor = ImGuiMouseCursor_COUNT;
+    ImGui_ImplWin32_UpdateKeyboardCodePage();
+
+    // Set platform dependent data in viewport
+    ImGui::GetMainViewport()->PlatformHandleRaw = (void*)hwnd;
+    IM_UNUSED(platform_has_own_dc); // Used in 'docking' branch
+
+    // Dynamically load XInput library
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+    bd->WantUpdateHasGamepad = true;
+    const char* xinput_dll_names[] =
+    {
+        "xinput1_4.dll",   // Windows 8+
+        "xinput1_3.dll",   // DirectX SDK
+        "xinput9_1_0.dll", // Windows Vista, Windows 7
+        "xinput1_2.dll",   // DirectX SDK
+        "xinput1_1.dll"    // DirectX SDK
+    };
+    for (int n = 0; n < IM_ARRAYSIZE(xinput_dll_names); n++)
+        if (HMODULE dll = ::LoadLibraryA(xinput_dll_names[n]))
+        {
+            bd->XInputDLL = dll;
+            bd->XInputGetCapabilities = (PFN_XInputGetCapabilities)::GetProcAddress(dll, "XInputGetCapabilities");
+            bd->XInputGetState = (PFN_XInputGetState)::GetProcAddress(dll, "XInputGetState");
+            break;
+        }
+#endif // IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+
+    return true;
+}
+
+IMGUI_IMPL_API bool     ImGui_ImplWin32_Init(void* hwnd)
+{
+    return ImGui_ImplWin32_InitEx(hwnd, false);
+}
+
+IMGUI_IMPL_API bool     ImGui_ImplWin32_InitForOpenGL(void* hwnd)
+{
+    // OpenGL needs CS_OWNDC
+    return ImGui_ImplWin32_InitEx(hwnd, true);
+}
+
+void    ImGui_ImplWin32_Shutdown()
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Unload XInput library
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+    if (bd->XInputDLL)
+        ::FreeLibrary(bd->XInputDLL);
+#endif // IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    IM_DELETE(bd);
+}
+
+static bool ImGui_ImplWin32_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return false;
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        ::SetCursor(nullptr);
+    }
+    else
+    {
+        // Show OS mouse cursor
+        LPTSTR win32_cursor = IDC_ARROW;
+        switch (imgui_cursor)
+        {
+        case ImGuiMouseCursor_Arrow:        win32_cursor = IDC_ARROW; break;
+        case ImGuiMouseCursor_TextInput:    win32_cursor = IDC_IBEAM; break;
+        case ImGuiMouseCursor_ResizeAll:    win32_cursor = IDC_SIZEALL; break;
+        case ImGuiMouseCursor_ResizeEW:     win32_cursor = IDC_SIZEWE; break;
+        case ImGuiMouseCursor_ResizeNS:     win32_cursor = IDC_SIZENS; break;
+        case ImGuiMouseCursor_ResizeNESW:   win32_cursor = IDC_SIZENESW; break;
+        case ImGuiMouseCursor_ResizeNWSE:   win32_cursor = IDC_SIZENWSE; break;
+        case ImGuiMouseCursor_Hand:         win32_cursor = IDC_HAND; break;
+        case ImGuiMouseCursor_NotAllowed:   win32_cursor = IDC_NO; break;
+        }
+        ::SetCursor(::LoadCursor(nullptr, win32_cursor));
+    }
+    return true;
+}
+
+static bool IsVkDown(int vk)
+{
+    return (::GetKeyState(vk) & 0x8000) != 0;
+}
+
+static void ImGui_ImplWin32_AddKeyEvent(ImGuiKey key, bool down, int native_keycode, int native_scancode = -1)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(key, down);
+    io.SetKeyEventNativeData(key, native_keycode, native_scancode); // To support legacy indexing (<1.87 user code)
+    IM_UNUSED(native_scancode);
+}
+
+static void ImGui_ImplWin32_ProcessKeyEventsWorkarounds()
+{
+    // Left & right Shift keys: when both are pressed together, Windows tend to not generate the WM_KEYUP event for the first released one.
+    if (ImGui::IsKeyDown(ImGuiKey_LeftShift) && !IsVkDown(VK_LSHIFT))
+        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftShift, false, VK_LSHIFT);
+    if (ImGui::IsKeyDown(ImGuiKey_RightShift) && !IsVkDown(VK_RSHIFT))
+        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightShift, false, VK_RSHIFT);
+
+    // Sometimes WM_KEYUP for Win key is not passed down to the app (e.g. for Win+V on some setups, according to GLFW).
+    if (ImGui::IsKeyDown(ImGuiKey_LeftSuper) && !IsVkDown(VK_LWIN))
+        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftSuper, false, VK_LWIN);
+    if (ImGui::IsKeyDown(ImGuiKey_RightSuper) && !IsVkDown(VK_RWIN))
+        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightSuper, false, VK_RWIN);
+}
+
+static void ImGui_ImplWin32_UpdateKeyModifiers()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(ImGuiMod_Ctrl, IsVkDown(VK_CONTROL));
+    io.AddKeyEvent(ImGuiMod_Shift, IsVkDown(VK_SHIFT));
+    io.AddKeyEvent(ImGuiMod_Alt, IsVkDown(VK_MENU));
+    io.AddKeyEvent(ImGuiMod_Super, IsVkDown(VK_APPS));
+}
+
+static void ImGui_ImplWin32_UpdateMouseData()
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(bd->hWnd != 0);
+
+    HWND focused_window = ::GetForegroundWindow();
+    const bool is_app_focused = (focused_window == bd->hWnd);
+    if (is_app_focused)
+    {
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        if (io.WantSetMousePos)
+        {
+            POINT pos = { (int)io.MousePos.x, (int)io.MousePos.y };
+            if (::ClientToScreen(bd->hWnd, &pos))
+                ::SetCursorPos(pos.x, pos.y);
+        }
+
+        // (Optional) Fallback to provide mouse position when focused (WM_MOUSEMOVE already provides this when hovered or captured)
+        // This also fills a short gap when clicking non-client area: WM_NCMOUSELEAVE -> modal OS move -> gap -> WM_NCMOUSEMOVE
+        if (!io.WantSetMousePos && bd->MouseTrackedArea == 0)
+        {
+            POINT pos;
+            if (::GetCursorPos(&pos) && ::ScreenToClient(bd->hWnd, &pos))
+                io.AddMousePosEvent((float)pos.x, (float)pos.y);
+        }
+    }
+}
+
+// Gamepad navigation mapping
+static void ImGui_ImplWin32_UpdateGamepads()
+{
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    //if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+    //    return;
+
+    // Calling XInputGetState() every frame on disconnected gamepads is unfortunately too slow.
+    // Instead we refresh gamepad availability by calling XInputGetCapabilities() _only_ after receiving WM_DEVICECHANGE.
+    if (bd->WantUpdateHasGamepad)
+    {
+        XINPUT_CAPABILITIES caps = {};
+        bd->HasGamepad = bd->XInputGetCapabilities ? (bd->XInputGetCapabilities(0, XINPUT_FLAG_GAMEPAD, &caps) == ERROR_SUCCESS) : false;
+        bd->WantUpdateHasGamepad = false;
+    }
+
+    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+    XINPUT_STATE xinput_state;
+    XINPUT_GAMEPAD& gamepad = xinput_state.Gamepad;
+    if (!bd->HasGamepad || bd->XInputGetState == nullptr || bd->XInputGetState(0, &xinput_state) != ERROR_SUCCESS)
+        return;
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+
+    #define IM_SATURATE(V)                      (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V)
+    #define MAP_BUTTON(KEY_NO, BUTTON_ENUM)     { io.AddKeyEvent(KEY_NO, (gamepad.wButtons & BUTTON_ENUM) != 0); }
+    #define MAP_ANALOG(KEY_NO, VALUE, V0, V1)   { float vn = (float)(VALUE - V0) / (float)(V1 - V0); io.AddKeyAnalogEvent(KEY_NO, vn > 0.10f, IM_SATURATE(vn)); }
+    MAP_BUTTON(ImGuiKey_GamepadStart,           XINPUT_GAMEPAD_START);
+    MAP_BUTTON(ImGuiKey_GamepadBack,            XINPUT_GAMEPAD_BACK);
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,        XINPUT_GAMEPAD_X);
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,       XINPUT_GAMEPAD_B);
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,          XINPUT_GAMEPAD_Y);
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,        XINPUT_GAMEPAD_A);
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,        XINPUT_GAMEPAD_DPAD_LEFT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,       XINPUT_GAMEPAD_DPAD_RIGHT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,          XINPUT_GAMEPAD_DPAD_UP);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,        XINPUT_GAMEPAD_DPAD_DOWN);
+    MAP_BUTTON(ImGuiKey_GamepadL1,              XINPUT_GAMEPAD_LEFT_SHOULDER);
+    MAP_BUTTON(ImGuiKey_GamepadR1,              XINPUT_GAMEPAD_RIGHT_SHOULDER);
+    MAP_ANALOG(ImGuiKey_GamepadL2,              gamepad.bLeftTrigger, XINPUT_GAMEPAD_TRIGGER_THRESHOLD, 255);
+    MAP_ANALOG(ImGuiKey_GamepadR2,              gamepad.bRightTrigger, XINPUT_GAMEPAD_TRIGGER_THRESHOLD, 255);
+    MAP_BUTTON(ImGuiKey_GamepadL3,              XINPUT_GAMEPAD_LEFT_THUMB);
+    MAP_BUTTON(ImGuiKey_GamepadR3,              XINPUT_GAMEPAD_RIGHT_THUMB);
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,      gamepad.sThumbLX, -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight,     gamepad.sThumbLX, +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,        gamepad.sThumbLY, +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,      gamepad.sThumbLY, -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,      gamepad.sThumbRX, -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight,     gamepad.sThumbRX, +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,        gamepad.sThumbRY, +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,      gamepad.sThumbRY, -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+#endif // #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+}
+
+void    ImGui_ImplWin32_NewFrame()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplWin32_Init()?");
+
+    // Setup display size (every frame to accommodate for window resizing)
+    RECT rect = { 0, 0, 0, 0 };
+    ::GetClientRect(bd->hWnd, &rect);
+    io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top));
+
+    // Setup time step
+    INT64 current_time = 0;
+    ::QueryPerformanceCounter((LARGE_INTEGER*)&current_time);
+    io.DeltaTime = (float)(current_time - bd->Time) / bd->TicksPerSecond;
+    bd->Time = current_time;
+
+    // Update OS mouse position
+    ImGui_ImplWin32_UpdateMouseData();
+
+    // Process workarounds for known Windows key handling issues
+    ImGui_ImplWin32_ProcessKeyEventsWorkarounds();
+
+    // Update OS mouse cursor with the cursor requested by imgui
+    ImGuiMouseCursor mouse_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
+    if (bd->LastMouseCursor != mouse_cursor)
+    {
+        bd->LastMouseCursor = mouse_cursor;
+        ImGui_ImplWin32_UpdateMouseCursor();
+    }
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplWin32_UpdateGamepads();
+}
+
+// There is no distinct VK_xxx for keypad enter, instead it is VK_RETURN + KF_EXTENDED, we assign it an arbitrary value to make code more readable (VK_ codes go up to 255)
+#define IM_VK_KEYPAD_ENTER      (VK_RETURN + 256)
+
+// Map VK_xxx to ImGuiKey_xxx.
+static ImGuiKey ImGui_ImplWin32_VirtualKeyToImGuiKey(WPARAM wParam)
+{
+    switch (wParam)
+    {
+        case VK_TAB: return ImGuiKey_Tab;
+        case VK_LEFT: return ImGuiKey_LeftArrow;
+        case VK_RIGHT: return ImGuiKey_RightArrow;
+        case VK_UP: return ImGuiKey_UpArrow;
+        case VK_DOWN: return ImGuiKey_DownArrow;
+        case VK_PRIOR: return ImGuiKey_PageUp;
+        case VK_NEXT: return ImGuiKey_PageDown;
+        case VK_HOME: return ImGuiKey_Home;
+        case VK_END: return ImGuiKey_End;
+        case VK_INSERT: return ImGuiKey_Insert;
+        case VK_DELETE: return ImGuiKey_Delete;
+        case VK_BACK: return ImGuiKey_Backspace;
+        case VK_SPACE: return ImGuiKey_Space;
+        case VK_RETURN: return ImGuiKey_Enter;
+        case VK_ESCAPE: return ImGuiKey_Escape;
+        case VK_OEM_7: return ImGuiKey_Apostrophe;
+        case VK_OEM_COMMA: return ImGuiKey_Comma;
+        case VK_OEM_MINUS: return ImGuiKey_Minus;
+        case VK_OEM_PERIOD: return ImGuiKey_Period;
+        case VK_OEM_2: return ImGuiKey_Slash;
+        case VK_OEM_1: return ImGuiKey_Semicolon;
+        case VK_OEM_PLUS: return ImGuiKey_Equal;
+        case VK_OEM_4: return ImGuiKey_LeftBracket;
+        case VK_OEM_5: return ImGuiKey_Backslash;
+        case VK_OEM_6: return ImGuiKey_RightBracket;
+        case VK_OEM_3: return ImGuiKey_GraveAccent;
+        case VK_CAPITAL: return ImGuiKey_CapsLock;
+        case VK_SCROLL: return ImGuiKey_ScrollLock;
+        case VK_NUMLOCK: return ImGuiKey_NumLock;
+        case VK_SNAPSHOT: return ImGuiKey_PrintScreen;
+        case VK_PAUSE: return ImGuiKey_Pause;
+        case VK_NUMPAD0: return ImGuiKey_Keypad0;
+        case VK_NUMPAD1: return ImGuiKey_Keypad1;
+        case VK_NUMPAD2: return ImGuiKey_Keypad2;
+        case VK_NUMPAD3: return ImGuiKey_Keypad3;
+        case VK_NUMPAD4: return ImGuiKey_Keypad4;
+        case VK_NUMPAD5: return ImGuiKey_Keypad5;
+        case VK_NUMPAD6: return ImGuiKey_Keypad6;
+        case VK_NUMPAD7: return ImGuiKey_Keypad7;
+        case VK_NUMPAD8: return ImGuiKey_Keypad8;
+        case VK_NUMPAD9: return ImGuiKey_Keypad9;
+        case VK_DECIMAL: return ImGuiKey_KeypadDecimal;
+        case VK_DIVIDE: return ImGuiKey_KeypadDivide;
+        case VK_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case VK_SUBTRACT: return ImGuiKey_KeypadSubtract;
+        case VK_ADD: return ImGuiKey_KeypadAdd;
+        case IM_VK_KEYPAD_ENTER: return ImGuiKey_KeypadEnter;
+        case VK_LSHIFT: return ImGuiKey_LeftShift;
+        case VK_LCONTROL: return ImGuiKey_LeftCtrl;
+        case VK_LMENU: return ImGuiKey_LeftAlt;
+        case VK_LWIN: return ImGuiKey_LeftSuper;
+        case VK_RSHIFT: return ImGuiKey_RightShift;
+        case VK_RCONTROL: return ImGuiKey_RightCtrl;
+        case VK_RMENU: return ImGuiKey_RightAlt;
+        case VK_RWIN: return ImGuiKey_RightSuper;
+        case VK_APPS: return ImGuiKey_Menu;
+        case '0': return ImGuiKey_0;
+        case '1': return ImGuiKey_1;
+        case '2': return ImGuiKey_2;
+        case '3': return ImGuiKey_3;
+        case '4': return ImGuiKey_4;
+        case '5': return ImGuiKey_5;
+        case '6': return ImGuiKey_6;
+        case '7': return ImGuiKey_7;
+        case '8': return ImGuiKey_8;
+        case '9': return ImGuiKey_9;
+        case 'A': return ImGuiKey_A;
+        case 'B': return ImGuiKey_B;
+        case 'C': return ImGuiKey_C;
+        case 'D': return ImGuiKey_D;
+        case 'E': return ImGuiKey_E;
+        case 'F': return ImGuiKey_F;
+        case 'G': return ImGuiKey_G;
+        case 'H': return ImGuiKey_H;
+        case 'I': return ImGuiKey_I;
+        case 'J': return ImGuiKey_J;
+        case 'K': return ImGuiKey_K;
+        case 'L': return ImGuiKey_L;
+        case 'M': return ImGuiKey_M;
+        case 'N': return ImGuiKey_N;
+        case 'O': return ImGuiKey_O;
+        case 'P': return ImGuiKey_P;
+        case 'Q': return ImGuiKey_Q;
+        case 'R': return ImGuiKey_R;
+        case 'S': return ImGuiKey_S;
+        case 'T': return ImGuiKey_T;
+        case 'U': return ImGuiKey_U;
+        case 'V': return ImGuiKey_V;
+        case 'W': return ImGuiKey_W;
+        case 'X': return ImGuiKey_X;
+        case 'Y': return ImGuiKey_Y;
+        case 'Z': return ImGuiKey_Z;
+        case VK_F1: return ImGuiKey_F1;
+        case VK_F2: return ImGuiKey_F2;
+        case VK_F3: return ImGuiKey_F3;
+        case VK_F4: return ImGuiKey_F4;
+        case VK_F5: return ImGuiKey_F5;
+        case VK_F6: return ImGuiKey_F6;
+        case VK_F7: return ImGuiKey_F7;
+        case VK_F8: return ImGuiKey_F8;
+        case VK_F9: return ImGuiKey_F9;
+        case VK_F10: return ImGuiKey_F10;
+        case VK_F11: return ImGuiKey_F11;
+        case VK_F12: return ImGuiKey_F12;
+        default: return ImGuiKey_None;
+    }
+}
+
+// Allow compilation with old Windows SDK. MinGW doesn't have default _WIN32_WINNT/WINVER versions.
+#ifndef WM_MOUSEHWHEEL
+#define WM_MOUSEHWHEEL 0x020E
+#endif
+#ifndef DBT_DEVNODES_CHANGED
+#define DBT_DEVNODES_CHANGED 0x0007
+#endif
+
+// Win32 message handler (process Win32 mouse/keyboard inputs, etc.)
+// Call from your application's message handler. Keep calling your message handler unless this function returns TRUE.
+// When implementing your own backend, you can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if Dear ImGui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to Dear ImGui, and hide them from your application based on those two flags.
+// PS: In this Win32 handler, we use the capture API (GetCapture/SetCapture/ReleaseCapture) to be able to read mouse coordinates when dragging mouse outside of our window bounds.
+// PS: We treat DBLCLK messages as regular mouse down messages, so this code will work on windows classes that have the CS_DBLCLKS flag set. Our own example app code doesn't set this flag.
+#if 0
+// Copy this line into your .cpp file to forward declare the function.
+extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
+#endif
+
+// See https://learn.microsoft.com/en-us/windows/win32/tablet/system-events-and-mouse-messages
+// Prefer to call this at the top of the message handler to avoid the possibility of other Win32 calls interfering with this.
+static ImGuiMouseSource GetMouseSourceFromMessageExtraInfo()
+{
+    LPARAM extra_info = ::GetMessageExtraInfo();
+    if ((extra_info & 0xFFFFFF80) == 0xFF515700)
+        return ImGuiMouseSource_Pen;
+    if ((extra_info & 0xFFFFFF80) == 0xFF515780)
+        return ImGuiMouseSource_TouchScreen;
+    return ImGuiMouseSource_Mouse;
+}
+
+IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+    if (ImGui::GetCurrentContext() == nullptr)
+        return 0;
+
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+
+    switch (msg)
+    {
+    case WM_MOUSEMOVE:
+    case WM_NCMOUSEMOVE:
+    {
+        // We need to call TrackMouseEvent in order to receive WM_MOUSELEAVE events
+        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        const int area = (msg == WM_MOUSEMOVE) ? 1 : 2;
+        bd->MouseHwnd = hwnd;
+        if (bd->MouseTrackedArea != area)
+        {
+            TRACKMOUSEEVENT tme_cancel = { sizeof(tme_cancel), TME_CANCEL, hwnd, 0 };
+            TRACKMOUSEEVENT tme_track = { sizeof(tme_track), (DWORD)((area == 2) ? (TME_LEAVE | TME_NONCLIENT) : TME_LEAVE), hwnd, 0 };
+            if (bd->MouseTrackedArea != 0)
+                ::TrackMouseEvent(&tme_cancel);
+            ::TrackMouseEvent(&tme_track);
+            bd->MouseTrackedArea = area;
+        }
+        POINT mouse_pos = { (LONG)GET_X_LPARAM(lParam), (LONG)GET_Y_LPARAM(lParam) };
+        if (msg == WM_NCMOUSEMOVE && ::ScreenToClient(hwnd, &mouse_pos) == FALSE) // WM_NCMOUSEMOVE are provided in absolute coordinates.
+            break;
+        io.AddMouseSourceEvent(mouse_source);
+        io.AddMousePosEvent((float)mouse_pos.x, (float)mouse_pos.y);
+        break;
+    }
+    case WM_MOUSELEAVE:
+    case WM_NCMOUSELEAVE:
+    {
+        const int area = (msg == WM_MOUSELEAVE) ? 1 : 2;
+        if (bd->MouseTrackedArea == area)
+        {
+            if (bd->MouseHwnd == hwnd)
+                bd->MouseHwnd = nullptr;
+            bd->MouseTrackedArea = 0;
+            io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+        }
+        break;
+    }
+    case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:
+    case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:
+    case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:
+    case WM_XBUTTONDOWN: case WM_XBUTTONDBLCLK:
+    {
+        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        int button = 0;
+        if (msg == WM_LBUTTONDOWN || msg == WM_LBUTTONDBLCLK) { button = 0; }
+        if (msg == WM_RBUTTONDOWN || msg == WM_RBUTTONDBLCLK) { button = 1; }
+        if (msg == WM_MBUTTONDOWN || msg == WM_MBUTTONDBLCLK) { button = 2; }
+        if (msg == WM_XBUTTONDOWN || msg == WM_XBUTTONDBLCLK) { button = (GET_XBUTTON_WPARAM(wParam) == XBUTTON1) ? 3 : 4; }
+        if (bd->MouseButtonsDown == 0 && ::GetCapture() == nullptr)
+            ::SetCapture(hwnd);
+        bd->MouseButtonsDown |= 1 << button;
+        io.AddMouseSourceEvent(mouse_source);
+        io.AddMouseButtonEvent(button, true);
+        return 0;
+    }
+    case WM_LBUTTONUP:
+    case WM_RBUTTONUP:
+    case WM_MBUTTONUP:
+    case WM_XBUTTONUP:
+    {
+        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        int button = 0;
+        if (msg == WM_LBUTTONUP) { button = 0; }
+        if (msg == WM_RBUTTONUP) { button = 1; }
+        if (msg == WM_MBUTTONUP) { button = 2; }
+        if (msg == WM_XBUTTONUP) { button = (GET_XBUTTON_WPARAM(wParam) == XBUTTON1) ? 3 : 4; }
+        bd->MouseButtonsDown &= ~(1 << button);
+        if (bd->MouseButtonsDown == 0 && ::GetCapture() == hwnd)
+            ::ReleaseCapture();
+        io.AddMouseSourceEvent(mouse_source);
+        io.AddMouseButtonEvent(button, false);
+        return 0;
+    }
+    case WM_MOUSEWHEEL:
+        io.AddMouseWheelEvent(0.0f, (float)GET_WHEEL_DELTA_WPARAM(wParam) / (float)WHEEL_DELTA);
+        return 0;
+    case WM_MOUSEHWHEEL:
+        io.AddMouseWheelEvent(-(float)GET_WHEEL_DELTA_WPARAM(wParam) / (float)WHEEL_DELTA, 0.0f);
+        return 0;
+    case WM_KEYDOWN:
+    case WM_KEYUP:
+    case WM_SYSKEYDOWN:
+    case WM_SYSKEYUP:
+    {
+        const bool is_key_down = (msg == WM_KEYDOWN || msg == WM_SYSKEYDOWN);
+        if (wParam < 256)
+        {
+            // Submit modifiers
+            ImGui_ImplWin32_UpdateKeyModifiers();
+
+            // Obtain virtual key code
+            // (keypad enter doesn't have its own... VK_RETURN with KF_EXTENDED flag means keypad enter, see IM_VK_KEYPAD_ENTER definition for details, it is mapped to ImGuiKey_KeyPadEnter.)
+            int vk = (int)wParam;
+            if ((wParam == VK_RETURN) && (HIWORD(lParam) & KF_EXTENDED))
+                vk = IM_VK_KEYPAD_ENTER;
+            const ImGuiKey key = ImGui_ImplWin32_VirtualKeyToImGuiKey(vk);
+            const int scancode = (int)LOBYTE(HIWORD(lParam));
+
+            // Special behavior for VK_SNAPSHOT / ImGuiKey_PrintScreen as Windows doesn't emit the key down event.
+            if (key == ImGuiKey_PrintScreen && !is_key_down)
+                ImGui_ImplWin32_AddKeyEvent(key, true, vk, scancode);
+
+            // Submit key event
+            if (key != ImGuiKey_None)
+                ImGui_ImplWin32_AddKeyEvent(key, is_key_down, vk, scancode);
+
+            // Submit individual left/right modifier events
+            if (vk == VK_SHIFT)
+            {
+                // Important: Shift keys tend to get stuck when pressed together, missing key-up events are corrected in ImGui_ImplWin32_ProcessKeyEventsWorkarounds()
+                if (IsVkDown(VK_LSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftShift, is_key_down, VK_LSHIFT, scancode); }
+                if (IsVkDown(VK_RSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightShift, is_key_down, VK_RSHIFT, scancode); }
+            }
+            else if (vk == VK_CONTROL)
+            {
+                if (IsVkDown(VK_LCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftCtrl, is_key_down, VK_LCONTROL, scancode); }
+                if (IsVkDown(VK_RCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightCtrl, is_key_down, VK_RCONTROL, scancode); }
+            }
+            else if (vk == VK_MENU)
+            {
+                if (IsVkDown(VK_LMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftAlt, is_key_down, VK_LMENU, scancode); }
+                if (IsVkDown(VK_RMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightAlt, is_key_down, VK_RMENU, scancode); }
+            }
+        }
+        return 0;
+    }
+    case WM_SETFOCUS:
+    case WM_KILLFOCUS:
+        io.AddFocusEvent(msg == WM_SETFOCUS);
+        return 0;
+    case WM_INPUTLANGCHANGE:
+        ImGui_ImplWin32_UpdateKeyboardCodePage();
+        return 0;
+    case WM_CHAR:
+        if (::IsWindowUnicode(hwnd))
+        {
+            // You can also use ToAscii()+GetKeyboardState() to retrieve characters.
+            if (wParam > 0 && wParam < 0x10000)
+                io.AddInputCharacterUTF16((unsigned short)wParam);
+        }
+        else
+        {
+            wchar_t wch = 0;
+            ::MultiByteToWideChar(bd->KeyboardCodePage, MB_PRECOMPOSED, (char*)&wParam, 1, &wch, 1);
+            io.AddInputCharacter(wch);
+        }
+        return 0;
+    case WM_SETCURSOR:
+        // This is required to restore cursor when transitioning from e.g resize borders to client area.
+        if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor())
+            return 1;
+        return 0;
+    case WM_DEVICECHANGE:
+#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+        if ((UINT)wParam == DBT_DEVNODES_CHANGED)
+            bd->WantUpdateHasGamepad = true;
+#endif
+        return 0;
+    }
+    return 0;
+}
+
+
+//--------------------------------------------------------------------------------------------------------
+// DPI-related helpers (optional)
+//--------------------------------------------------------------------------------------------------------
+// - Use to enable DPI awareness without having to create an application manifest.
+// - Your own app may already do this via a manifest or explicit calls. This is mostly useful for our examples/ apps.
+// - In theory we could call simple functions from Windows SDK such as SetProcessDPIAware(), SetProcessDpiAwareness(), etc.
+//   but most of the functions provided by Microsoft require Windows 8.1/10+ SDK at compile time and Windows 8/10+ at runtime,
+//   neither we want to require the user to have. So we dynamically select and load those functions to avoid dependencies.
+//---------------------------------------------------------------------------------------------------------
+// This is the scheme successfully used by GLFW (from which we borrowed some of the code) and other apps aiming to be highly portable.
+// ImGui_ImplWin32_EnableDpiAwareness() is just a helper called by main.cpp, we don't call it automatically.
+// If you are trying to implement your own backend for your own engine, you may ignore that noise.
+//---------------------------------------------------------------------------------------------------------
+
+// Perform our own check with RtlVerifyVersionInfo() instead of using functions from <VersionHelpers.h> as they
+// require a manifest to be functional for checks above 8.1. See https://github.com/ocornut/imgui/issues/4200
+static BOOL _IsWindowsVersionOrGreater(WORD major, WORD minor, WORD)
+{
+    typedef LONG(WINAPI* PFN_RtlVerifyVersionInfo)(OSVERSIONINFOEXW*, ULONG, ULONGLONG);
+    static PFN_RtlVerifyVersionInfo RtlVerifyVersionInfoFn = nullptr;
+	if (RtlVerifyVersionInfoFn == nullptr)
+		if (HMODULE ntdllModule = ::GetModuleHandleA("ntdll.dll"))
+			RtlVerifyVersionInfoFn = (PFN_RtlVerifyVersionInfo)GetProcAddress(ntdllModule, "RtlVerifyVersionInfo");
+    if (RtlVerifyVersionInfoFn == nullptr)
+        return FALSE;
+
+    RTL_OSVERSIONINFOEXW versionInfo = { };
+    ULONGLONG conditionMask = 0;
+    versionInfo.dwOSVersionInfoSize = sizeof(RTL_OSVERSIONINFOEXW);
+    versionInfo.dwMajorVersion = major;
+	versionInfo.dwMinorVersion = minor;
+	VER_SET_CONDITION(conditionMask, VER_MAJORVERSION, VER_GREATER_EQUAL);
+	VER_SET_CONDITION(conditionMask, VER_MINORVERSION, VER_GREATER_EQUAL);
+	return (RtlVerifyVersionInfoFn(&versionInfo, VER_MAJORVERSION | VER_MINORVERSION, conditionMask) == 0) ? TRUE : FALSE;
+}
+
+#define _IsWindowsVistaOrGreater()   _IsWindowsVersionOrGreater(HIBYTE(0x0600), LOBYTE(0x0600), 0) // _WIN32_WINNT_VISTA
+#define _IsWindows8OrGreater()       _IsWindowsVersionOrGreater(HIBYTE(0x0602), LOBYTE(0x0602), 0) // _WIN32_WINNT_WIN8
+#define _IsWindows8Point1OrGreater() _IsWindowsVersionOrGreater(HIBYTE(0x0603), LOBYTE(0x0603), 0) // _WIN32_WINNT_WINBLUE
+#define _IsWindows10OrGreater()      _IsWindowsVersionOrGreater(HIBYTE(0x0A00), LOBYTE(0x0A00), 0) // _WIN32_WINNT_WINTHRESHOLD / _WIN32_WINNT_WIN10
+
+#ifndef DPI_ENUMS_DECLARED
+typedef enum { PROCESS_DPI_UNAWARE = 0, PROCESS_SYSTEM_DPI_AWARE = 1, PROCESS_PER_MONITOR_DPI_AWARE = 2 } PROCESS_DPI_AWARENESS;
+typedef enum { MDT_EFFECTIVE_DPI = 0, MDT_ANGULAR_DPI = 1, MDT_RAW_DPI = 2, MDT_DEFAULT = MDT_EFFECTIVE_DPI } MONITOR_DPI_TYPE;
+#endif
+#ifndef _DPI_AWARENESS_CONTEXTS_
+DECLARE_HANDLE(DPI_AWARENESS_CONTEXT);
+#define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE    (DPI_AWARENESS_CONTEXT)-3
+#endif
+#ifndef DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2
+#define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2 (DPI_AWARENESS_CONTEXT)-4
+#endif
+typedef HRESULT(WINAPI* PFN_SetProcessDpiAwareness)(PROCESS_DPI_AWARENESS);                     // Shcore.lib + dll, Windows 8.1+
+typedef HRESULT(WINAPI* PFN_GetDpiForMonitor)(HMONITOR, MONITOR_DPI_TYPE, UINT*, UINT*);        // Shcore.lib + dll, Windows 8.1+
+typedef DPI_AWARENESS_CONTEXT(WINAPI* PFN_SetThreadDpiAwarenessContext)(DPI_AWARENESS_CONTEXT); // User32.lib + dll, Windows 10 v1607+ (Creators Update)
+
+// Helper function to enable DPI awareness without setting up a manifest
+void ImGui_ImplWin32_EnableDpiAwareness()
+{
+    if (_IsWindows10OrGreater())
+    {
+        static HINSTANCE user32_dll = ::LoadLibraryA("user32.dll"); // Reference counted per-process
+        if (PFN_SetThreadDpiAwarenessContext SetThreadDpiAwarenessContextFn = (PFN_SetThreadDpiAwarenessContext)::GetProcAddress(user32_dll, "SetThreadDpiAwarenessContext"))
+        {
+            SetThreadDpiAwarenessContextFn(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
+            return;
+        }
+    }
+    if (_IsWindows8Point1OrGreater())
+    {
+        static HINSTANCE shcore_dll = ::LoadLibraryA("shcore.dll"); // Reference counted per-process
+        if (PFN_SetProcessDpiAwareness SetProcessDpiAwarenessFn = (PFN_SetProcessDpiAwareness)::GetProcAddress(shcore_dll, "SetProcessDpiAwareness"))
+        {
+            SetProcessDpiAwarenessFn(PROCESS_PER_MONITOR_DPI_AWARE);
+            return;
+        }
+    }
+#if _WIN32_WINNT >= 0x0600
+    ::SetProcessDPIAware();
+#endif
+}
+
+#if defined(_MSC_VER) && !defined(NOGDI)
+#pragma comment(lib, "gdi32")   // Link with gdi32.lib for GetDeviceCaps(). MinGW will require linking with '-lgdi32'
+#endif
+
+float ImGui_ImplWin32_GetDpiScaleForMonitor(void* monitor)
+{
+    UINT xdpi = 96, ydpi = 96;
+    if (_IsWindows8Point1OrGreater())
+    {
+		static HINSTANCE shcore_dll = ::LoadLibraryA("shcore.dll"); // Reference counted per-process
+		static PFN_GetDpiForMonitor GetDpiForMonitorFn = nullptr;
+		if (GetDpiForMonitorFn == nullptr && shcore_dll != nullptr)
+            GetDpiForMonitorFn = (PFN_GetDpiForMonitor)::GetProcAddress(shcore_dll, "GetDpiForMonitor");
+		if (GetDpiForMonitorFn != nullptr)
+		{
+			GetDpiForMonitorFn((HMONITOR)monitor, MDT_EFFECTIVE_DPI, &xdpi, &ydpi);
+            IM_ASSERT(xdpi == ydpi); // Please contact me if you hit this assert!
+			return xdpi / 96.0f;
+		}
+    }
+#ifndef NOGDI
+    const HDC dc = ::GetDC(nullptr);
+    xdpi = ::GetDeviceCaps(dc, LOGPIXELSX);
+    ydpi = ::GetDeviceCaps(dc, LOGPIXELSY);
+    IM_ASSERT(xdpi == ydpi); // Please contact me if you hit this assert!
+    ::ReleaseDC(nullptr, dc);
+#endif
+    return xdpi / 96.0f;
+}
+
+float ImGui_ImplWin32_GetDpiScaleForHwnd(void* hwnd)
+{
+    HMONITOR monitor = ::MonitorFromWindow((HWND)hwnd, MONITOR_DEFAULTTONEAREST);
+    return ImGui_ImplWin32_GetDpiScaleForMonitor(monitor);
+}
+
+//---------------------------------------------------------------------------------------------------------
+// Transparency related helpers (optional)
+//--------------------------------------------------------------------------------------------------------
+
+#if defined(_MSC_VER)
+#pragma comment(lib, "dwmapi")  // Link with dwmapi.lib. MinGW will require linking with '-ldwmapi'
+#endif
+
+// [experimental]
+// Borrowed from GLFW's function updateFramebufferTransparency() in src/win32_window.c
+// (the Dwm* functions are Vista era functions but we are borrowing logic from GLFW)
+void ImGui_ImplWin32_EnableAlphaCompositing(void* hwnd)
+{
+    if (!_IsWindowsVistaOrGreater())
+        return;
+
+    BOOL composition;
+    if (FAILED(::DwmIsCompositionEnabled(&composition)) || !composition)
+        return;
+
+    BOOL opaque;
+    DWORD color;
+    if (_IsWindows8OrGreater() || (SUCCEEDED(::DwmGetColorizationColor(&color, &opaque)) && !opaque))
+    {
+        HRGN region = ::CreateRectRgn(0, 0, -1, -1);
+        DWM_BLURBEHIND bb = {};
+        bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
+        bb.hRgnBlur = region;
+        bb.fEnable = TRUE;
+        ::DwmEnableBlurBehindWindow((HWND)hwnd, &bb);
+        ::DeleteObject(region);
+    }
+    else
+    {
+        DWM_BLURBEHIND bb = {};
+        bb.dwFlags = DWM_BB_ENABLE;
+        ::DwmEnableBlurBehindWindow((HWND)hwnd, &bb);
+    }
+}
+
+//---------------------------------------------------------------------------------------------------------
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/imgui_impl_win32.h

@@ -0,0 +1,52 @@
+// dear imgui: Platform Backend for Windows (standard windows API for 32-bits AND 64-bits applications)
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+
+// Implemented features:
+//  [X] Platform: Clipboard support (for Win32 this is actually part of core dear imgui)
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+
+// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+#ifndef IMGUI_DISABLE
+
+IMGUI_IMPL_API bool     ImGui_ImplWin32_Init(void* hwnd);
+IMGUI_IMPL_API bool     ImGui_ImplWin32_InitForOpenGL(void* hwnd);
+IMGUI_IMPL_API void     ImGui_ImplWin32_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplWin32_NewFrame();
+
+// Win32 message handler your application need to call.
+// - Intentionally commented out in a '#if 0' block to avoid dragging dependencies on <windows.h> from this helper.
+// - You should COPY the line below into your .cpp code to forward declare the function and then you can call it.
+// - Call from your application's message handler. Keep calling your message handler unless this function returns TRUE.
+
+#if 0
+extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
+#endif
+
+// DPI-related helpers (optional)
+// - Use to enable DPI awareness without having to create an application manifest.
+// - Your own app may already do this via a manifest or explicit calls. This is mostly useful for our examples/ apps.
+// - In theory we could call simple functions from Windows SDK such as SetProcessDPIAware(), SetProcessDpiAwareness(), etc.
+//   but most of the functions provided by Microsoft require Windows 8.1/10+ SDK at compile time and Windows 8/10+ at runtime,
+//   neither we want to require the user to have. So we dynamically select and load those functions to avoid dependencies.
+IMGUI_IMPL_API void     ImGui_ImplWin32_EnableDpiAwareness();
+IMGUI_IMPL_API float    ImGui_ImplWin32_GetDpiScaleForHwnd(void* hwnd);       // HWND hwnd
+IMGUI_IMPL_API float    ImGui_ImplWin32_GetDpiScaleForMonitor(void* monitor); // HMONITOR monitor
+
+// Transparency related helpers (optional) [experimental]
+// - Use to enable alpha compositing transparency with the desktop.
+// - Use together with e.g. clearing your framebuffer with zero-alpha.
+IMGUI_IMPL_API void     ImGui_ImplWin32_EnableAlphaCompositing(void* hwnd);   // HWND hwnd
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/backends/vulkan/generate_spv.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+## -V: create SPIR-V binary
+## -x: save binary output as text-based 32-bit hexadecimal numbers
+## -o: output file
+glslangValidator -V -x -o glsl_shader.frag.u32 glsl_shader.frag
+glslangValidator -V -x -o glsl_shader.vert.u32 glsl_shader.vert

ext/imgui/backends/vulkan/glsl_shader.frag

@@ -0,0 +1,14 @@
+#version 450 core
+layout(location = 0) out vec4 fColor;
+
+layout(set=0, binding=0) uniform sampler2D sTexture;
+
+layout(location = 0) in struct {
+    vec4 Color;
+    vec2 UV;
+} In;
+
+void main()
+{
+    fColor = In.Color * texture(sTexture, In.UV.st);
+}

ext/imgui/backends/vulkan/glsl_shader.vert

@@ -0,0 +1,25 @@
+#version 450 core
+layout(location = 0) in vec2 aPos;
+layout(location = 1) in vec2 aUV;
+layout(location = 2) in vec4 aColor;
+
+layout(push_constant) uniform uPushConstant {
+    vec2 uScale;
+    vec2 uTranslate;
+} pc;
+
+out gl_PerVertex {
+    vec4 gl_Position;
+};
+
+layout(location = 0) out struct {
+    vec4 Color;
+    vec2 UV;
+} Out;
+
+void main()
+{
+    Out.Color = aColor;
+    Out.UV = aUV;
+    gl_Position = vec4(aPos * pc.uScale + pc.uTranslate, 0, 1);
+}

ext/imgui/docs/BACKENDS.md

@@ -0,0 +1,146 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Backends
+
+**The backends/ folder contains backends for popular platforms/graphics API, which you can use in
+your application or engine to easily integrate Dear ImGui.** Each backend is typically self-contained in a pair of files: imgui_impl_XXXX.cpp + imgui_impl_XXXX.h.
+
+- The 'Platform' backends are in charge of: mouse/keyboard/gamepad inputs, cursor shape, timing, and windowing.<BR>
+  e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), SDL2 ([imgui_impl_sdl2.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl2.cpp)), etc.
+
+- The 'Renderer' backends are in charge of: creating atlas texture, and rendering imgui draw data.<BR>
+  e.g. DirectX11 ([imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)), OpenGL/WebGL ([imgui_impl_opengl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_opengl3.cpp)), Vulkan ([imgui_impl_vulkan.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_vulkan.cpp)), etc.
+
+- For some high-level frameworks, a single backend usually handles both 'Platform' and 'Renderer' parts.<BR>
+  e.g. Allegro 5 ([imgui_impl_allegro5.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_allegro5.cpp)). If you end up creating a custom backend for your engine, you may want to do the same.
+
+An application usually combines one Platform backend + one Renderer backend + main Dear ImGui sources.
+For example, the [example_win32_directx11](https://github.com/ocornut/imgui/tree/master/examples/example_win32_directx11) application combines imgui_impl_win32.cpp + imgui_impl_dx11.cpp. There are 20+ examples in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder. See [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for details.
+
+**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
+
+
+### What are backends?
+
+Dear ImGui is highly portable and only requires a few things to run and render, typically:
+
+ - Required: providing mouse/keyboard inputs (fed into the `ImGuiIO` structure).
+ - Required: uploading the font atlas texture into graphics memory.
+ - Required: rendering indexed textured triangles with a clipping rectangle.
+
+ Extra features are opt-in, our backends try to support as many as possible:
+
+ - Optional: custom texture binding support.
+ - Optional: clipboard support.
+ - Optional: gamepad support.
+ - Optional: mouse cursor shape support.
+ - Optional: IME support.
+ - Optional: multi-viewports support.
+ etc.
+
+This is essentially what each backend is doing + obligatory portability cruft. Using default backends ensure you can get all those features including the ones that would be harder to implement on your side (e.g. multi-viewports support).
+
+It is important to understand the difference between the core Dear ImGui library (files in the root folder)
+and the backends which we are describing here (backends/ folder).
+
+- Some issues may only be backend or platform specific.
+- You should be able to write backends for pretty much any platform and any 3D graphics API.
+  e.g. you can get creative and use software rendering or render remotely on a different machine.
+
+
+### Integrating a backend
+
+See "Getting Started" section of [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for more details.
+
+
+### List of backends
+
+In the [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder:
+
+List of Platforms Backends:
+
+    imgui_impl_android.cpp    ; Android native app API
+    imgui_impl_glfw.cpp       ; GLFW (Windows, macOS, Linux, etc.) http://www.glfw.org/
+    imgui_impl_osx.mm         ; macOS native API (not as feature complete as glfw/sdl backends)
+    imgui_impl_sdl2.cpp       ; SDL2 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org
+    imgui_impl_sdl3.cpp       ; SDL3 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org (*EXPERIMENTAL UNTIL SDL3 IS RELEASED*)
+    imgui_impl_win32.cpp      ; Win32 native API (Windows)
+    imgui_impl_glut.cpp       ; GLUT/FreeGLUT (this is prehistoric software and absolutely not recommended today!)
+
+List of Renderer Backends:
+
+    imgui_impl_dx9.cpp        ; DirectX9
+    imgui_impl_dx10.cpp       ; DirectX10
+    imgui_impl_dx11.cpp       ; DirectX11
+    imgui_impl_dx12.cpp       ; DirectX12
+    imgui_impl_metal.mm       ; Metal (with ObjC)
+    imgui_impl_opengl2.cpp    ; OpenGL 2 (legacy, fixed pipeline <- don't use with modern OpenGL context)
+    imgui_impl_opengl3.cpp    ; OpenGL 3/4, OpenGL ES 2, OpenGL ES 3 (modern programmable pipeline)
+    imgui_impl_sdlrenderer2.cpp ; SDL_Renderer (optional component of SDL2 available from SDL 2.0.18+)
+    imgui_impl_sdlrenderer3.cpp ; SDL_Renderer (optional component of SDL3 available from SDL 3.0.0+)
+    imgui_impl_vulkan.cpp     ; Vulkan
+    imgui_impl_wgpu.cpp       ; WebGPU
+
+List of high-level Frameworks Backends (combining Platform + Renderer):
+
+    imgui_impl_allegro5.cpp
+
+Emscripten is also supported!
+The SDL+GL, GLFW+GL and SDL+WebGPU examples are all ready to build and run with Emscripten.
+
+### Backends for third-party frameworks, graphics API or other languages
+
+See https://github.com/ocornut/imgui/wiki/Bindings for the full list (e.g. Adventure Game Studio, Cinder, Cocos2d-x, Game Maker Studio2, Godot, LÖVE+LUA, Magnum, Monogame, Ogre, openFrameworks, OpenSceneGraph, SFML, Sokol, Unity, Unreal Engine and many others).
+
+### Recommended Backends
+
+If you are not sure which backend to use, the recommended platform/frameworks for portable applications:
+
+|Library |Website |Backend |Note |
+|--------|--------|--------|-----|
+| GLFW | https://github.com/glfw/glfw | imgui_impl_glfw.cpp | |
+| SDL2 | https://www.libsdl.org | imgui_impl_sdl2.cpp | |
+| Sokol | https://github.com/floooh/sokol | [util/sokol_imgui.h](https://github.com/floooh/sokol/blob/master/util/sokol_imgui.h) | Lower-level than GLFW/SDL |
+
+
+### Using a custom engine?
+
+You will likely be tempted to start by rewrite your own backend using your own custom/high-level facilities...<BR>
+Think twice!
+
+If you are new to Dear ImGui, first try using the existing backends as-is.
+You will save lots of time integrating the library.
+You can LATER decide to rewrite yourself a custom backend if you really need to.
+In most situations, custom backends have fewer features and more bugs than the standard backends we provide.
+If you want portability, you can use multiple backends and choose between them either at compile time
+or at runtime.
+
+**Example A**: your engine is built over Windows + DirectX11 but you have your own high-level rendering
+system layered over DirectX11.<BR>
+Suggestion: try using imgui_impl_win32.cpp + imgui_impl_dx11.cpp first.
+Once it works, if you really need it, you can replace the imgui_impl_dx11.cpp code with a
+custom renderer using your own rendering functions, and keep using the standard Win32 code etc.
+
+**Example B**: your engine runs on Windows, Mac, Linux and uses DirectX11, Metal, and Vulkan respectively.<BR>
+Suggestion: use multiple generic backends!
+Once it works, if you really need it, you can replace parts of backends with your own abstractions.
+
+**Example C**: your engine runs on platforms we can't provide public backends for (e.g. PS4/PS5, Switch),
+and you have high-level systems everywhere.<BR>
+Suggestion: try using a non-portable backend first (e.g. win32 + underlying graphics API) to get
+your desktop builds working first. This will get you running faster and get your acquainted with
+how Dear ImGui works and is setup. You can then rewrite a custom backend using your own engine API...
+
+Generally:
+It is unlikely you will add value to your project by creating your own backend.
+
+Also:
+The [multi-viewports feature](https://github.com/ocornut/imgui/issues/1542) of the 'docking' branch allows
+Dear ImGui windows to be seamlessly detached from the main application window. This is achieved using an
+extra layer to the Platform and Renderer backends, which allows Dear ImGui to communicate platform-specific
+requests such as: "create an additional OS window", "create a render context", "get the OS position of this
+window" etc. See 'ImGuiPlatformIO' for details.
+Supporting the multi-viewports feature correctly using 100% of your own abstractions is more difficult
+than supporting single-viewport.
+If you decide to use unmodified imgui_impl_XXXX.cpp files, you can automatically benefit from
+improvements and fixes related to viewports and platform windows without extra work on your side.

ext/imgui/docs/CONTRIBUTING.md

@@ -0,0 +1,81 @@
+# Contributing Guidelines
+
+## Index
+
+- [Getting Started & General Advice](#getting-started--general-advice)
+- [Issues vs Discussions](#issues-vs-discussions)
+- [How to open an Issue](#how-to-open-an-issue)
+- [How to open a Pull Request](#how-to-open-a-pull-request)
+- [Copyright / Contributor License Agreement](#copyright--contributor-license-agreement)
+
+## Getting Started & General Advice
+
+- Article: [How To Ask Good Questions](https://bit.ly/3nwRnx1).
+- Please browse the [Wiki](https://github.com/ocornut/imgui/wiki) to find code snippets, links and other resources (e.g. [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started), [Useful extensions](https://github.com/ocornut/imgui/wiki/Useful-Extensions)).
+- Please read [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) if your question relates to setting up Dear ImGui.
+- Please read [docs/FAQ.md](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md).
+- Please read [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) if your question relates to fonts or text.
+- Please run `ImGui::ShowDemoWindow()` to explore the demo and its sources.
+- Please use the search function of your IDE to search for symbols and comments related to your situation.
+- Please use the search function of GitHub to look for similar topics (always include 'Closed' issues/pr in your search).
+- You may [browse issues by Labels](https://github.com/ocornut/imgui/labels).
+- Please use a web search engine to look for similar issues.
+- If you get a crash or assert, use a debugger to locate the line triggering it and read the comments around.
+- Please don't be a [Help Vampire](https://slash7.com/2006/12/22/vampires/).
+
+## 'Issues' vs 'Discussions'
+
+We are happy to use 'Issues' for many type of open-ended questions. We are encouraging 'Issues' becoming an enormous, centralized and cross-referenced database of Dear ImGui contents.
+
+Only if you:
+- Cannot BUILD or LINK examples.
+- Cannot BUILD, or LINK, or RUN Dear ImGui in your application or custom engine.
+- Cannot LOAD a font.
+
+Then please [use the Discussions forums](https://github.com/ocornut/imgui/discussions) instead of opening an issue.
+
+If Dear ImGui is successfully showing in your app and you have used Dear ImGui before, you can open an Issue. Any form of discussions is welcome as a new issue. 
+
+## How to open an issue
+
+You may use the Issue Tracker to submit bug reports, feature requests or suggestions. You may ask for help or advice as well. But **PLEASE CAREFULLY READ THIS WALL OF TEXT. ISSUES IGNORING THOSE GUIDELINES MAY BE CLOSED. USERS IGNORING THOSE GUIDELINES MIGHT BE BLOCKED.**
+
+Please do your best to clarify your request. The amount of incomplete or ambiguous requests due to people not following those guidelines is often overwhelming. Issues created without the requested information may be closed prematurely. Exceptionally entitled, impolite, or lazy requests may lead to bans.
+
+**PLEASE UNDERSTAND THAT OPEN-SOURCE SOFTWARE LIVES OR DIES BY THE AMOUNT OF ENERGY MAINTAINERS CAN SPARE. WE HAVE LOTS OF STUFF TO DO. THIS IS AN ATTENTION ECONOMY AND MANY LAZY OR MINOR ISSUES ARE HOGGING OUR ATTENTION AND DRAINING ENERGY, TAKING US AWAY FROM MORE IMPORTANT WORK.**
+
+Steps:
+
+- Article: [How To Ask Good Questions](https://bit.ly/3nwRnx1).
+- **PLEASE DO FILL THE REQUESTED NEW ISSUE TEMPLATE.** Including Dear ImGui version number, branch name, platform/renderer back-ends (imgui_impl_XXX files), operating system.
+- **Try to be explicit with your GOALS, your EXPECTATIONS and what you have tried**.  Be mindful of [The XY Problem](http://xyproblem.info/). What you have in mind or in your code is not obvious to other people. People frequently discuss problems and suggest incorrect solutions without first clarifying their goals. When requesting a new feature, please describe the usage context (how you intend to use it, why you need it, etc.). If you tried something and it failed, show us what you tried.
+- **Please INCLUDE CODE. Provide a Minimal, Complete, and Verifiable Example ([MCVE](https://stackoverflow.com/help/mcve)) to demonstrate your problem**. An ideal submission includes a small piece of code that anyone can paste into one of the examples applications (examples/../main.cpp) or demo (imgui_demo.cpp) to understand and reproduce it. **Narrowing your problem to its shortest and purest form is the easiest way to understand it, explain it and fix it**. Please test your shortened code to ensure it exhibits the problem. **Often while creating the MCVE you will solve the problem!** Many questions that are missing a standalone verifiable example are missing the actual cause of their issue in the description, which ends up wasting everyone's time.
+- **Attach screenshots (or GIF/video) to clarify the context**. They often convey useful information that is omitted by the description. You can drag pictures/files in the message edit box. Avoid using 3rd party image hosting services, prefer the long-term longevity of GitHub attachments (you can drag pictures into your post). On Windows, you can use [ScreenToGif](https://www.screentogif.com/) to easily capture .gif files.
+- **If you are discussing an assert or a crash, please provide a debugger callstack**. Never state "it crashes" without additional information. If you don't know how to use a debugger and retrieve a callstack, learning about it will be useful.
+- **Please make sure that your project has asserts enabled.** Calls to IM_ASSERT() are scattered in the code to help catch common issues. When an assert is triggered read the comments around it. By default IM_ASSERT() calls the standard assert() function. To verify that your asserts are enabled, add the line `IM_ASSERT(false);` in your main() function. Your application should display an error message and abort. If your application doesn't report an error, your asserts are disabled. 
+- Please state if you have made substantial modifications to your copy of Dear ImGui or the back-end.
+- If you are not calling Dear ImGui directly from C++, please provide information about your Language and the wrapper/binding you are using.
+- Be mindful that messages are being sent to the mailbox of "Watching" users. Try to proofread your messages before sending them. Edits are not seen by those users unless they browse the site.
+
+**Some unfortunate words of warning**
+- If you are involved in cheating schemes (e.g. DLL injection) for competitive online multiplayer games, please don't post here. We won't answer and you will be blocked. It doesn't matter if your question relates to said project. We've had too many of you and need to project our time and sanity.
+- Due to frequent abuse of this service from the aforementioned users, if your GitHub account is anonymous and was created five minutes ago please understand that your post will receive more scrutiny and incomplete questions will be harshly dismissed.
+
+If you have been using Dear ImGui for a while or have been using C/C++ for several years or have demonstrated good behavior here, it is ok to not fulfill every item to the letter. Those are guidelines and experienced users or members of the community will know which information is useful in a given context.
+
+## How to open a Pull Request
+
+- **Please understand that by submitting a PR you are also submitting a request for the maintainer to review your code and then take over its maintenance.** PR should be crafted both in the interest of the end-users and also to ease the maintainer into understanding and accepting it. 
+- Many PRs are useful to demonstrate a need and a possible solution but aren't adequate for merging (causing other issues, not seeing other aspects of the big picture, etc.). In doubt, don't hesitate to push a PR because that is always the first step toward pointing toward a problem, and finding the mergeable solution! Even if a PR stays unmerged for a long time, its presence can be useful for other users and helps toward finding a general solution.
+- **When adding a feature,** please describe the usage context (how you intend to use it, why you need it, etc.). Be mindful of [The XY Problem](http://xyproblem.info/). 
+- **When fixing a warning or compilation problem,** please post the compiler log and specify the compiler version and platform you are using.
+- **Attach screenshots (or GIF/video) to clarify the context and demonstrate the feature at a glance.** You can drag pictures/files in the message edit box. Prefer the long-term longevity of GitHub attachments over 3rd party hosting (you can drag pictures into your post).
+- **Make sure your code follows the coding style already used in the codebase:** 4 spaces indentations (no tabs), `local_variable`, `FunctionName()`, `MemberName`, `// Text Comment`, `//CodeComment();`, C-style casts, etc.. We don't use modern C++ idioms and tend to use only a minimum of C++11 features. The applications under examples/ are generally less consistent because they sometimes try to mimic the coding style often adopted by a certain ecosystem (e.g. DirectX-related code tend to use the style of their sample). 
+- **Make sure you create a branch dedicated to the pull request**. In Git, 1 PR is associated to 1 branch. If you keep pushing to the same branch after you submitted the PR, your new commits will appear in the PR (we can still cherry-pick individual commits).
+
+## Copyright / Contributor License Agreement
+
+Any code you submit will become part of the repository and be distributed under the [Dear ImGui license](https://github.com/ocornut/imgui/blob/master/LICENSE.txt). By submitting code to the project you agree that the code is your work and that you can give it to the project.
+
+You also agree by submitting your code that you grant all transferrable rights to the code to the project maintainer, including for example re-licensing the code, modifying the code, and distributing it in source or binary forms. Specifically, this includes a requirement that you assign copyright to the project maintainer. For this reason, do not modify any copyright statements in files in any PRs.
+

ext/imgui/docs/EXAMPLES.md

@@ -0,0 +1,245 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Examples
+
+**The [examples/](https://github.com/ocornut/imgui/blob/master/examples) folder example applications (standalone, ready-to-build) for variety of
+platforms and graphics APIs.** They all use standard backends from the [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder (see [BACKENDS.md](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md)).
+
+The purpose of Examples is to showcase integration with backends, let you try Dear ImGui, and guide you toward
+integrating Dear ImGui in your own application/game/engine.
+**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
+
+You can find Windows binaries for some of those example applications at:
+  https://www.dearimgui.com/binaries
+
+
+### Getting Started
+
+Integration in a typical existing application, should take <20 lines when using standard backends.
+
+```cpp
+At initialization:
+  call ImGui::CreateContext()
+  call ImGui_ImplXXXX_Init() for each backend.
+
+At the beginning of your frame:
+  call ImGui_ImplXXXX_NewFrame() for each backend.
+  call ImGui::NewFrame()
+
+At the end of your frame:
+  call ImGui::Render()
+  call ImGui_ImplXXXX_RenderDrawData() for your Renderer backend.
+
+At shutdown:
+  call ImGui_ImplXXXX_Shutdown() for each backend.
+  call ImGui::DestroyContext()
+```
+
+Example (using [backends/imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp) + [backends/imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)):
+
+```cpp
+// Create a Dear ImGui context, setup some options
+ImGui::CreateContext();
+ImGuiIO& io = ImGui::GetIO();
+io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable some options
+
+// Initialize Platform + Renderer backends (here: using imgui_impl_win32.cpp + imgui_impl_dx11.cpp)
+ImGui_ImplWin32_Init(my_hwnd);
+ImGui_ImplDX11_Init(my_d3d_device, my_d3d_device_context);
+
+// Application main loop
+while (true)
+{
+    // Beginning of frame: update Renderer + Platform backend, start Dear ImGui frame
+    ImGui_ImplDX11_NewFrame();
+    ImGui_ImplWin32_NewFrame();
+    ImGui::NewFrame();
+
+    // Any application code here
+    ImGui::Text("Hello, world!");
+
+    // End of frame: render Dear ImGui
+    ImGui::Render();
+    ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
+
+    // Swap
+    g_pSwapChain->Present(1, 0);
+}
+
+// Shutdown
+ImGui_ImplDX11_Shutdown();
+ImGui_ImplWin32_Shutdown();
+ImGui::DestroyContext();
+```
+
+Please read 'PROGRAMMER GUIDE' in imgui.cpp for notes on how to setup Dear ImGui in your codebase.
+Please read the comments and instruction at the top of each file.
+Please read FAQ at https://www.dearimgui.com/faq
+
+If you are using any of the backends provided here, you can add the backends/imgui_impl_xxxx(.cpp,.h)
+files to your project and use as-in. Each imgui_impl_xxxx.cpp file comes with its own individual
+Changelog, so if you want to update them later it will be easier to catch up with what changed.
+
+
+### Examples Applications
+
+[example_allegro5/](https://github.com/ocornut/imgui/blob/master/examples/example_allegro5/) <BR>
+Allegro 5 example. <BR>
+= main.cpp + imgui_impl_allegro5.cpp
+
+[example_android_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_android_opengl3/) <BR>
+Android + OpenGL3 (ES) example. <BR>
+= main.cpp + imgui_impl_android.cpp + imgui_impl_opengl3.cpp
+
+[example_apple_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_metal/) <BR>
+OSX & iOS + Metal example. <BR>
+= main.m + imgui_impl_osx.mm + imgui_impl_metal.mm <BR>
+It is based on the "cross-platform" game template provided with Xcode as of Xcode 9.
+(NB: imgui_impl_osx.mm is currently not as feature complete as other platforms backends.
+You may prefer to use the GLFW Or SDL backends, which will also support Windows and Linux.)
+
+[example_apple_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_apple_opengl2/) <BR>
+OSX + OpenGL2 example. <BR>
+= main.mm + imgui_impl_osx.mm + imgui_impl_opengl2.cpp <BR>
+(NB: imgui_impl_osx.mm is currently not as feature complete as other platforms backends.
+ You may prefer to use the GLFW Or SDL backends, which will also support Windows and Linux.)
+
+[example_emscripten_wgpu/](https://github.com/ocornut/imgui/blob/master/examples/example_emscripten_wgpu/) <BR>
+Emcripten + GLFW + WebGPU example. <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_wgpu.cpp
+Note that the 'example_glfw_opengl3' and 'example_sdl2_opengl3' examples also supports Emscripten!
+
+[example_glfw_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_metal/) <BR>
+GLFW (Mac) + Metal example. <BR>
+= main.mm + imgui_impl_glfw.cpp + imgui_impl_metal.mm
+
+[example_glfw_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_opengl2/) <BR>
+GLFW + OpenGL2 example (legacy, fixed pipeline). <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_opengl2.cpp <BR>
+**DO NOT USE THIS IF YOUR CODE/ENGINE IS USING MODERN GL or WEBGL (SHADERS, VBO, VAO, etc.)** <BR>
+This code is mostly provided as a reference to learn about Dear ImGui integration, because it is shorter.
+If your code is using GL3+ context or any semi modern GL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many GL attributes to their initial
+state, and might confuse your GPU driver. One star, not recommended.
+
+[example_glfw_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_opengl3/) <BR>
+GLFW (Win32, Mac, Linux) + OpenGL3+/ES2/ES3 example (modern, programmable pipeline). <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern GL calls and custom shaders.<BR>
+This support building with Emscripten and targetting WebGL.<BR>
+Prefer using that if you are using modern GL or WebGL in your application.
+
+[example_glfw_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_glfw_vulkan/) <BR>
+GLFW (Win32, Mac, Linux) + Vulkan example. <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_vulkan.cpp <BR>
+This is quite long and tedious, because: Vulkan.
+For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
+
+[example_glut_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_glut_opengl2/) <BR>
+GLUT (e.g., FreeGLUT on Linux/Windows, GLUT framework on OSX) + OpenGL2 example. <BR>
+= main.cpp + imgui_impl_glut.cpp + imgui_impl_opengl2.cpp <BR>
+Note that GLUT/FreeGLUT is largely obsolete software, prefer using GLFW or SDL.
+
+[example_null/](https://github.com/ocornut/imgui/blob/master/examples/example_null/) <BR>
+Null example, compile and link imgui, create context, run headless with no inputs and no graphics output. <BR>
+= main.cpp <BR>
+This is used to quickly test compilation of core imgui files in as many setups as possible.
+Because this application doesn't create a window nor a graphic context, there's no graphics output.
+
+[example_sdl2_directx11/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_directx11/) <BR>
+SDL2 + DirectX11 example, Windows only. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_dx11.cpp <BR>
+This to demonstrate usage of DirectX with SDL2.
+
+[example_sdl2_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_metal/) <BR>
+SDL2 + Metal example, Mac only. <BR>
+= main.mm + imgui_impl_sdl2.cpp + imgui_impl_metal.mm
+
+[example_sdl2_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_opengl2/) <BR>
+SDL2 (Win32, Mac, Linux etc.) + OpenGL example (legacy, fixed pipeline). <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_opengl2.cpp <BR>
+**DO NOT USE OPENGL2 CODE IF YOUR CODE/ENGINE IS USING GL OR WEBGL (SHADERS, VBO, VAO, etc.)** <BR>
+This code is mostly provided as a reference to learn about Dear ImGui integration, because it is shorter.
+If your code is using GL3+ context or any semi modern GL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many GL attributes to their initial
+state, and might confuse your GPU driver. One star, not recommended.
+
+[example_sdl2_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_opengl3/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + OpenGL3+/ES2/ES3 example. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern GL calls and custom shaders. <BR>
+This support building with Emscripten and targetting WebGL.<BR>
+Prefer using that if you are using modern GL or WebGL in your application.
+
+[example_sdl2_sdlrenderer2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_sdlrenderer2/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + SDL_Renderer for SDL2 (most graphics backends are supported underneath) <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_sdlrenderer.cpp <BR>
+This requires SDL 2.0.18+ (released November 2021) <BR>
+
+[example_sdl2_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_vulkan/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + Vulkan example. <BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_vulkan.cpp <BR>
+This is quite long and tedious, because: Vulkan. <BR>
+For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
+
+[example_win32_directx9/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx9/) <BR>
+DirectX9 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx9.cpp
+
+[example_win32_directx10/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx10/) <BR>
+DirectX10 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx10.cpp
+
+[example_win32_directx11/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx11/) <BR>
+DirectX11 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx11.cpp
+
+[example_win32_directx12/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx12/) <BR>
+DirectX12 example, Windows only. <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_dx12.cpp <BR>
+This is quite long and tedious, because: DirectX12.
+
+[example_win32_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_opengl3/) <BR>
+Raw Windows + OpenGL3 + example (modern, programmable pipeline) <BR>
+= main.cpp + imgui_impl_win32.cpp + imgui_impl_opengl3.cpp <BR>
+
+
+### Miscellaneous
+
+**Building**
+
+Unfortunately nowadays it is still tedious to create and maintain portable build files using external
+libraries (the kind we're using here to create a window and render 3D triangles) without relying on
+third party software and build systems. For most examples here we choose to provide:
+ - Makefiles for Linux/OSX
+ - Batch files for Visual Studio 2008+
+ - A .sln project file for Visual Studio 2012+
+ - Xcode project files for the Apple examples
+Please let us know if they don't work with your setup!
+You can probably just import the imgui_impl_xxx.cpp/.h files into your own codebase or compile those
+directly with a command-line compiler.
+
+If you are interested in using Cmake to build and links examples, see:
+  https://github.com/ocornut/imgui/pull/1713 and https://github.com/ocornut/imgui/pull/3027
+
+**About mouse cursor latency**
+
+Dear ImGui has no particular extra lag for most behaviors,
+e.g. the last value passed to 'io.AddMousePosEvent()' before NewFrame() will result in windows being moved
+to the right spot at the time of EndFrame()/Render(). At 60 FPS your experience should be pleasant.
+
+However, consider that OS mouse cursors are typically drawn through a very specific hardware accelerated
+path and will feel smoother than the majority of contents rendered via regular graphics API (including,
+but not limited to Dear ImGui windows). Because UI rendering and interaction happens on the same plane
+as the mouse, that disconnect may be jarring to particularly sensitive users.
+You may experiment with enabling the io.MouseDrawCursor flag to request Dear ImGui to draw a mouse cursor
+using the regular graphics API, to help you visualize the difference between a "hardware" cursor and a
+regularly rendered software cursor.
+However, rendering a mouse cursor at 60 FPS will feel sluggish so you likely won't want to enable that at
+all times. It might be beneficial for the user experience to switch to a software rendered cursor _only_
+when an interactive drag is in progress.
+
+Note that some setup or GPU drivers are likely to be causing extra display lag depending on their settings.
+If you feel that dragging windows feels laggy and you are not sure what the cause is: try to build a simple
+drawing a flat 2D shape directly under the mouse cursor!
+

ext/imgui/docs/FAQ.md

@@ -0,0 +1,680 @@
+# FAQ (Frequently Asked Questions)
+
+You may link to this document using short form:
+  https://www.dearimgui.com/faq
+or its real address:
+  https://github.com/ocornut/imgui/blob/master/docs/FAQ.md
+or view this file with any Markdown viewer.
+
+
+## Index
+
+| **Q&A: Basics** |
+:---------------------------------------------------------- |
+| [Where is the documentation?](#q-where-is-the-documentation) |
+| [What is this library called?](#q-what-is-this-library-called) |
+| [Which version should I get?](#q-which-version-should-i-get) |
+| **Q&A: Integration** |
+| **[How to get started?](#q-how-to-get-started)** |
+| **[How can I tell whether to dispatch mouse/keyboard to Dear ImGui or my application?](#q-how-can-i-tell-whether-to-dispatch-mousekeyboard-to-dear-imgui-or-my-application)** |
+| [How can I enable keyboard or gamepad controls?](#q-how-can-i-enable-keyboard-or-gamepad-controls) |
+| [How can I use this on a machine without mouse, keyboard or screen? (input share, remote display)](#q-how-can-i-use-this-on-a-machine-without-mouse-keyboard-or-screen-input-share-remote-display) |
+| [I integrated Dear ImGui in my engine and little squares are showing instead of text...](#q-i-integrated-dear-imgui-in-my-engine-and-little-squares-are-showing-instead-of-text) |
+| [I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around...](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-clipping-or-disappearing-when-i-move-windows-around) |
+| [I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries...](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-displaying-outside-their-expected-windows-boundaries) |
+| **Q&A: Usage** |
+| **[About the ID Stack system..<br>Why is my widget not reacting when I click on it?<br>How can I have widgets with an empty label?<br>How can I have multiple widgets with the same label?<br>How can I have multiple windows with the same label?](#q-about-the-id-stack-system)** |
+| [How can I display an image? What is ImTextureID, how does it work?](#q-how-can-i-display-an-image-what-is-imtextureid-how-does-it-work)|
+| [How can I use maths operators with ImVec2?](#q-how-can-i-use-maths-operators-with-imvec2) |
+| [How can I use my own maths types instead of ImVec2/ImVec4?](#q-how-can-i-use-my-own-maths-types-instead-of-imvec2imvec4) |
+| [How can I interact with standard C++ types (such as std::string and std::vector)?](#q-how-can-i-interact-with-standard-c-types-such-as-stdstring-and-stdvector) |
+| [How can I display custom shapes? (using low-level ImDrawList API)](#q-how-can-i-display-custom-shapes-using-low-level-imdrawlist-api) |
+| **Q&A: Fonts, Text** |
+| [How should I handle DPI in my application?](#q-how-should-i-handle-dpi-in-my-application) |
+| [How can I load a different font than the default?](#q-how-can-i-load-a-different-font-than-the-default) |
+| [How can I easily use icons in my application?](#q-how-can-i-easily-use-icons-in-my-application) |
+| [How can I load multiple fonts?](#q-how-can-i-load-multiple-fonts) |
+| [How can I display and input non-Latin characters such as Chinese, Japanese, Korean, Cyrillic?](#q-how-can-i-display-and-input-non-latin-characters-such-as-chinese-japanese-korean-cyrillic) |
+| **Q&A: Concerns** |
+| [Who uses Dear ImGui?](#q-who-uses-dear-imgui) |
+| [Can you create elaborate/serious tools with Dear ImGui?](#q-can-you-create-elaborateserious-tools-with-dear-imgui)  |
+| [Can you reskin the look of Dear ImGui?](#q-can-you-reskin-the-look-of-dear-imgui) |
+| [Why using C++ (as opposed to C)?](#q-why-using-c-as-opposed-to-c) |
+| **Q&A: Community** |
+| [How can I help?](#q-how-can-i-help) |
+
+
+# Q&A: Basics
+
+### Q: Where is the documentation?
+
+**This library is poorly documented at the moment and expects the user to be acquainted with C/C++.**
+- The [Wiki](https://github.com/ocornut/imgui/wiki) is a hub to many resources and links.
+- Handy [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide to integrate Dear ImGui in an existing application.
+- 20+ standalone example applications using e.g. OpenGL/DirectX are provided in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder to explain how to integrate Dear ImGui with your own engine/application. You can run those applications and explore them.
+- See demo code in [imgui_demo.cpp](https://github.com/ocornut/imgui/blob/master/imgui_demo.cpp) and particularly the `ImGui::ShowDemoWindow()` function. The demo covers most features of Dear ImGui, so you can read the code and see its output.
+- See documentation: [Backends](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md), [Examples](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md), [Fonts](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md).
+- See documentation and comments at the top of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp) + general API comments in [imgui.h](https://github.com/ocornut/imgui/blob/master/imgui.h).
+- The [Glossary](https://github.com/ocornut/imgui/wiki/Glossary) page may be useful.
+- The [Issues](https://github.com/ocornut/imgui/issues) and [Discussions](https://github.com/ocornut/imgui/discussions) sections can be searched for past questions and issues.
+- Your programming IDE is your friend, find the type or function declaration to find comments associated with it.
+- The `ImGui::ShowMetricsWindow()` function exposes lots of internal information and tools. Although it is primarily designed as a debugging tool, having access to that information tends to help understands concepts.
+
+##### [Return to Index](#index)
+
+---
+
+### Q. What is this library called?
+
+**This library is called Dear ImGui**. Please refer to it as Dear ImGui (not ImGui, not IMGUI).
+
+(The library misleadingly started its life in 2014 as "ImGui" due to the fact that I didn't give it a proper name when I released 1.0, and had no particular expectation that it would take off. However, the term IMGUI (immediate-mode graphical user interface) was coined before and is being used in variety of other situations e.g. Unity uses it own implementation of the IMGUI paradigm. To reduce the ambiguity without affecting existing code bases, I have decided in December 2015 a fully qualified name "Dear ImGui" for this library.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Which version should I get?
+I occasionally tag [Releases](https://github.com/ocornut/imgui/releases) but it is generally safe and recommended to sync to master/latest. The library is fairly stable and regressions tend to be fixed fast when reported.
+
+You may use the [docking](https://github.com/ocornut/imgui/tree/docking) branch which includes:
+- [Docking features](https://github.com/ocornut/imgui/issues/2109)
+- [Multi-viewport features](https://github.com/ocornut/imgui/issues/1542)
+
+Many projects are using this branch and it is kept in sync with master regularly.
+
+##### [Return to Index](#index)
+
+----
+
+# Q&A: Integration
+
+### Q: How to get started?
+
+Read [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started). <BR>
+Read [EXAMPLES.md](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md). <BR>
+Read [BACKENDS.md](https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md). <BR>
+Read `PROGRAMMER GUIDE` section of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp). <BR>
+The [Wiki](https://github.com/ocornut/imgui/wiki) is a hub to many resources and links.
+
+For first-time users having issues compiling/linking/running or issues loading fonts, please use [GitHub Discussions](https://github.com/ocornut/imgui/discussions).
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I tell whether to dispatch mouse/keyboard to Dear ImGui or my application?
+
+You can read the `io.WantCaptureMouse`, `io.WantCaptureKeyboard` and `io.WantTextInput` flags from the ImGuiIO structure.
+- When `io.WantCaptureMouse` is set, you need to discard/hide the mouse inputs from your underlying application.
+- When `io.WantCaptureKeyboard` is set, you need to discard/hide the keyboard inputs from your underlying application.
+- When `io.WantTextInput` is set, you can notify your OS/engine to popup an on-screen keyboard, if available (e.g. on a mobile phone, or console OS).
+
+Important: you should always pass your mouse/keyboard inputs to Dear ImGui, regardless of the value `io.WantCaptureMouse`/`io.WantCaptureKeyboard`. This is because e.g. we need to detect that you clicked in the void to unfocus its own windows, and other reasons.
+
+```cpp
+void MyLowLevelMouseButtonHandler(int button, bool down)
+{
+    // (1) ALWAYS forward mouse data to ImGui! This is automatic with default backends. With your own backend:
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddMouseButtonEvent(button, down);
+
+    // (2) ONLY forward mouse data to your underlying app/game.
+    if (!io.WantCaptureMouse)
+        my_game->HandleMouseData(...);
+}
+```
+
+
+**Note:** The `io.WantCaptureMouse` is more correct that any manual attempt to "check if the mouse is hovering a window" (don't do that!). It handles mouse dragging correctly (both dragging that started over your application or over a Dear ImGui window) and handle e.g. popup and modal windows blocking inputs.
+
+**Note:** Those flags are updated by `ImGui::NewFrame()`. However it is generally more correct and easier that you poll flags from the previous frame, then submit your inputs, then call `NewFrame()`. If you attempt to do the opposite (which is generally harder) you are likely going to submit your inputs after `NewFrame()`, and therefore too late.
+
+**Note:** If you are using a touch device, you may find use for an early call to `UpdateHoveredWindowAndCaptureFlags()` to correctly dispatch your initial touch. We will work on better out-of-the-box touch support in the future.
+
+**Note:** Text input widget releases focus on the "KeyDown" event of the Return key, so the subsequent "KeyUp" event that your application receive will typically have `io.WantCaptureKeyboard == false`. Depending on your application logic it may or not be inconvenient to receive that KeyUp event. You might want to track which key-downs were targeted for Dear ImGui, e.g. with an array of bool, and filter out the corresponding key-ups.)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I enable keyboard or gamepad controls?
+- The gamepad/keyboard navigation is fairly functional and keeps being improved. The initial focus was to support game controllers, but keyboard is becoming increasingly and decently usable. Gamepad support is particularly useful to use Dear ImGui on a game console (e.g. PS4, Switch, XB1) without a mouse connected!
+- Keyboard: set `io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard` to enable.
+- Gamepad: set `io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad` to enable (with a supporting backend).
+- See [Control Sheets for Gamepads](https://www.dearimgui.com/controls_sheets) (reference PNG/PSD for PS4, XB1, Switch gamepads).
+- See `USING GAMEPAD/KEYBOARD NAVIGATION CONTROLS` section of [imgui.cpp](https://github.com/ocornut/imgui/blob/master/imgui.cpp) for more details.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use this on a machine without mouse, keyboard or screen? (input share, remote display)
+- You can share your computer mouse seamlessly with your console/tablet/phone using solutions such as [Synergy](https://symless.com/synergy)
+This is the preferred solution for developer productivity.
+In particular, the [micro-synergy-client repository](https://github.com/symless/micro-synergy-client) has simple
+and portable source code (uSynergy.c/.h) for a small embeddable client that you can use on any platform to connect
+to your host computer, based on the Synergy 1.x protocol. Make sure you download the Synergy 1 server on your computer.
+Console SDK also sometimes provide equivalent tooling or wrapper for Synergy-like protocols.
+- Game console users: consider emulating a mouse cursor with DualShock4 touch pad or a spare analog stick as a mouse-emulation fallback.
+- You may also use a third party solution such as [netImgui](https://github.com/sammyfreg/netImgui), [Remote ImGui](https://github.com/JordiRos/remoteimgui) or [imgui-ws](https://github.com/ggerganov/imgui-ws) which sends the vertices to render over the local network, allowing you to use Dear ImGui even on a screen-less machine. See [Wiki](https://github.com/ocornut/imgui/wiki) index for most details.
+- For touch inputs, you can increase the hit box of widgets (via the `style.TouchPadding` setting) to accommodate for the lack of precision of touch inputs, but it is recommended you use a mouse or gamepad to allow optimizing for screen real-estate and precision.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: I integrated Dear ImGui in my engine and little squares are showing instead of text...
+Your renderer backend is not using the font texture correctly or it hasn't been uploaded to the GPU.
+- If this happens using the standard backends: A) have you modified the font atlas after `ImGui_ImplXXX_NewFrame()`? B) maybe the texture failed to upload, which **can if your texture atlas is too big**. Also see [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md).
+- If this happens with a custom backend: make sure you have uploaded the font texture to the GPU, that all shaders are rendering states are setup properly (e.g. texture is bound). Compare your code to existing backends and use a graphics debugger such as [RenderDoc](https://renderdoc.org) to debug your rendering states.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around...
+### Q: I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries...
+You are probably mishandling the clipping rectangles in your render function.
+Each draw command needs the triangle rendered using the clipping rectangle provided in the ImDrawCmd structure (`ImDrawCmd->CllipRect`).
+Rectangles provided by Dear ImGui are defined as
+`(x1=left,y1=top,x2=right,y2=bottom)`
+and **NOT** as
+`(x1,y1,width,height)`.
+Refer to rendering backends in the [backends/](https://github.com/ocornut/imgui/tree/master/backends) folder for references of how to handle the `ClipRect` field.
+For example, the [DirectX11 backend](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp) does this:
+```cpp
+// Project scissor/clipping rectangles into framebuffer space
+ImVec2 clip_off = draw_data->DisplayPos;
+ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
+ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
+if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+    continue;
+
+// Apply scissor/clipping rectangle
+const D3D11_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+ctx->RSSetScissorRects(1, &r);
+```
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Usage
+
+### Q: About the ID Stack system...
+### Q: Why is my widget not reacting when I click on it?
+### Q: How can I have widgets with an empty label?
+### Q: How can I have multiple widgets with the same label?
+### Q: How can I have multiple windows with the same label?
+
+A primer on labels and the ID Stack...
+
+Dear ImGui internally needs to uniquely identify UI elements.
+Elements that are typically not clickable (such as calls to the Text functions) don't need an ID.
+Interactive widgets (such as calls to Button buttons) need a unique ID.
+
+**Unique IDs are used internally to track active widgets and occasionally associate state to widgets.<BR>
+Unique IDs are implicitly built from the hash of multiple elements that identify the "path" to the UI element.**
+
+Since Dear ImGui 1.85, you can use `Demo>Tools>ID Stack Tool` or call `ImGui::ShowIDStackToolWindow()`. The tool display intermediate values leading to the creation of a unique ID, making things easier to debug and understand.
+
+![Stack tool](https://user-images.githubusercontent.com/8225057/136235657-a0ea5665-dcd1-423f-9be6-dc3f8ced8f12.png)
+
+- Unique ID are often derived from a string label and at minimum scoped within their host window:
+```cpp
+Begin("MyWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyWindow", "OK")
+Button("Cancel");      // Label = "Cancel", ID = hash of ("MyWindow", "Cancel")
+End();
+```
+- Other elements such as tree nodes, etc. also pushes to the ID stack:
+```cpp
+Begin("MyWindow");
+if (TreeNode("MyTreeNode"))
+{
+    Button("OK");      // Label = "OK",     ID = hash of ("MyWindow", "MyTreeNode", "OK")
+    TreePop();
+}
+End();
+```
+- Two items labeled "OK" in different windows or different tree locations won't collide:
+```cpp
+Begin("MyFirstWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyFirstWindow", "OK")
+End();
+Begin("MyOtherWindow");
+Button("OK");          // Label = "OK",     ID = hash of ("MyOtherWindow", "OK")
+End();
+```
+
+- If you have a same ID twice in the same location, you'll have a conflict:
+```cpp
+Begin("MyWindow");
+Button("OK");
+Button("OK");      // ERROR: ID collision with the first button! Interacting with either button will trigger the first one.
+Button("");        // ERROR: ID collision with Begin("MyWindow")!
+End();
+```
+Fear not! This is easy to solve and there are many ways to solve it!
+
+- Solving ID conflict in a simple/local context:
+When passing a label you can optionally specify extra ID information within the string itself.
+Use "##" to pass a complement to the ID that won't be visible to the end-user.
+This helps solve the simple collision cases when you know e.g. at compilation time which items
+are going to be created:
+```cpp
+Begin("MyWindow");
+Button("Play");        // Label = "Play",   ID = hash of ("MyWindow", "Play")
+Button("Play##foo1");  // Label = "Play",   ID = hash of ("MyWindow", "Play##foo1")  // Different from other buttons
+Button("Play##foo2");  // Label = "Play",   ID = hash of ("MyWindow", "Play##foo2")  // Different from other buttons
+Button("##foo");       // Label = "",       ID = hash of ("MyWindow", "##foo")       // Different from window
+End();
+```
+- If you want to completely hide the label, but still need an ID:
+```cpp
+Checkbox("##On", &b);  // Label = "",       ID = hash of (..., "##On")   // No visible label, just a checkbox!
+```
+- Occasionally/rarely you might want to change a label while preserving a constant ID. This allows
+you to animate labels. For example, you may want to include varying information in a window title bar,
+but windows are uniquely identified by their ID. Use "###" to pass a label that isn't part of ID:
+```cpp
+Button("Hello###ID");  // Label = "Hello",  ID = hash of (..., "###ID")
+Button("World###ID");  // Label = "World",  ID = hash of (..., "###ID")  // Same ID, different label
+
+sprintf(buf, "My game (%f FPS)###MyGame", fps);
+Begin(buf);            // Variable title,   ID = hash of "MyGame"
+```
+- Solving ID conflict in a more general manner:
+Use `PushID()` / `PopID()` to create scopes and manipulate the ID stack, as to avoid ID conflicts
+within the same window. This is the most convenient way of distinguishing ID when iterating and
+creating many UI elements programmatically.
+You can push a pointer, a string, or an integer value into the ID stack.
+Remember that IDs are formed from the concatenation of _everything_ pushed into the ID stack.
+At each level of the stack, we store the seed used for items at this level of the ID stack.
+```cpp
+Begin("Window");
+for (int i = 0; i < 100; i++)
+{
+  PushID(i);           // Push i to the id tack
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", i, "Click")
+  PopID();
+}
+for (int i = 0; i < 100; i++)
+{
+  MyObject* obj = Objects[i];
+  PushID(obj);
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", obj pointer, "Click")
+  PopID();
+}
+for (int i = 0; i < 100; i++)
+{
+  MyObject* obj = Objects[i];
+  PushID(obj->Name);
+  Button("Click");     // Label = "Click",  ID = hash of ("Window", obj->Name, "Click")
+  PopID();
+}
+End();
+```
+- You can stack multiple prefixes into the ID stack:
+```cpp
+Button("Click");       // Label = "Click",  ID = hash of (..., "Click")
+PushID("node");
+  Button("Click");     // Label = "Click",  ID = hash of (..., "node", "Click")
+  PushID(my_ptr);
+    Button("Click");   // Label = "Click",  ID = hash of (..., "node", my_ptr, "Click")
+  PopID();
+PopID();
+```
+- Tree nodes implicitly create a scope for you by calling `PushID()`:
+```cpp
+Button("Click");       // Label = "Click",  ID = hash of (..., "Click")
+if (TreeNode("node"))  // <-- this function call will do a PushID() for you (unless instructed not to, with a special flag)
+{
+  Button("Click");     // Label = "Click",  ID = hash of (..., "node", "Click")
+  TreePop();
+}
+```
+
+When working with trees, IDs are used to preserve the open/close state of each tree node.
+Depending on your use cases you may want to use strings, indices, or pointers as ID.
+- e.g. when following a single pointer that may change over time, using a static string as ID
+will preserve your node open/closed state when the targeted object change.
+- e.g. when displaying a list of objects, using indices or pointers as ID will preserve the
+node open/closed state differently. See what makes more sense in your situation!
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display an image? What is ImTextureID, how does it work?
+
+Short explanation:
+- Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki).
+- You may use functions such as `ImGui::Image()`, `ImGui::ImageButton()` or lower-level `ImDrawList::AddImage()` to emit draw calls that will use your own textures.
+- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as ImTextureID (void*) value.
+- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason).
+
+**Please read documentations or tutorials on your graphics API to understand how to display textures on the screen before moving onward.**
+
+Long explanation:
+- Dear ImGui's job is to create "meshes", defined in a renderer-agnostic format made of draw commands and vertices. At the end of the frame, those meshes (ImDrawList) will be displayed by your rendering function. They are made up of textured polygons and the code to render them is generally fairly short (a few dozen lines). In the examples/ folder, we provide functions for popular graphics APIs (OpenGL, DirectX, etc.).
+- Each rendering function decides on a data type to represent "textures". The concept of what is a "texture" is entirely tied to your underlying engine/graphics API.
+ We carry the information to identify a "texture" in the ImTextureID type.
+ImTextureID is nothing more than a void*, aka 4/8 bytes worth of data: just enough to store one pointer or integer of your choice.
+Dear ImGui doesn't know or understand what you are storing in ImTextureID, it merely passes ImTextureID values until they reach your rendering function.
+- In the [examples/](https://github.com/ocornut/imgui/tree/master/examples) backends, for each graphics API we decided on a type that is likely to be a good representation for specifying an image from the end-user perspective. This is what the _examples_ rendering functions are using:
+```cpp
+OpenGL:
+- ImTextureID = GLuint
+- See ImGui_ImplOpenGL3_RenderDrawData() function in imgui_impl_opengl3.cpp
+```
+```cpp
+DirectX9:
+- ImTextureID = LPDIRECT3DTEXTURE9
+- See ImGui_ImplDX9_RenderDrawData() function in imgui_impl_dx9.cpp
+```
+```cpp
+DirectX11:
+- ImTextureID = ID3D11ShaderResourceView*
+- See ImGui_ImplDX11_RenderDrawData() function in imgui_impl_dx11.cpp
+```
+```cpp
+DirectX12:
+- ImTextureID = D3D12_GPU_DESCRIPTOR_HANDLE
+- See ImGui_ImplDX12_RenderDrawData() function in imgui_impl_dx12.cpp
+```
+For example, in the OpenGL example backend we store raw OpenGL texture identifier (GLuint) inside ImTextureID.
+Whereas in the DirectX11 example backend we store a pointer to ID3D11ShaderResourceView inside ImTextureID, which is a higher-level structure tying together both the texture and information about its format and how to read it.
+
+- If you have a custom engine built over e.g. OpenGL, instead of passing GLuint around you may decide to use a high-level data type to carry information about the texture as well as how to display it (shaders, etc.). The decision of what to use as ImTextureID can always be made better by knowing how your codebase is designed. If your engine has high-level data types for "textures" and "material" then you may want to use them.
+If you are starting with OpenGL or DirectX or Vulkan and haven't built much of a rendering engine over them, keeping the default ImTextureID representation suggested by the example backends is probably the best choice.
+(Advanced users may also decide to keep a low-level type in ImTextureID, use ImDrawList callback and pass information to their renderer)
+
+User code may do:
+```cpp
+// Cast our texture type to ImTextureID / void*
+MyTexture* texture = g_CoffeeTableTexture;
+ImGui::Image((void*)texture, ImVec2(texture->Width, texture->Height));
+```
+The renderer function called after ImGui::Render() will receive that same value that the user code passed:
+```cpp
+// Cast ImTextureID / void* stored in the draw command as our texture type
+MyTexture* texture = (MyTexture*)pcmd->GetTexID();
+MyEngineBindTexture2D(texture);
+```
+Once you understand this design, you will understand that loading image files and turning them into displayable textures is not within the scope of Dear ImGui.
+This is by design and is a good thing because it means your code has full control over your data types and how you display them.
+If you want to display an image file (e.g. PNG file) on the screen, please refer to documentation and tutorials for the graphics API you are using.
+
+Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki) to find simplified examples for loading textures with OpenGL, DirectX9 and DirectX11.
+
+C/C++ tip: a void* is pointer-sized storage. You may safely store any pointer or integer into it by casting your value to ImTextureID / void*, and vice-versa.
+Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID / void*.
+Here are some examples:
+```cpp
+GLuint my_tex = XXX;
+void* my_void_ptr;
+my_void_ptr = (void*)(intptr_t)my_tex;                  // cast a GLuint into a void* (we don't take its address! we literally store the value inside the pointer)
+my_tex = (GLuint)(intptr_t)my_void_ptr;                 // cast a void* into a GLuint
+
+ID3D11ShaderResourceView* my_dx11_srv = XXX;
+void* my_void_ptr;
+my_void_ptr = (void*)my_dx11_srv;                       // cast a ID3D11ShaderResourceView* into an opaque void*
+my_dx11_srv = (ID3D11ShaderResourceView*)my_void_ptr;   // cast a void* into a ID3D11ShaderResourceView*
+```
+Finally, you may call `ImGui::ShowMetricsWindow()` to explore/visualize/understand how the ImDrawList are generated.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use maths operators with ImVec2?
+
+We do not export maths operators by default in imgui.h in order to not conflict with the use of your own maths types and maths operators. As a convenience, you may use `#defne IMGUI_DEFINE_MATH_OPERATORS` + `#include "imgui.h"` to access our basic maths operators.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I use my own maths types instead of ImVec2/ImVec4?
+
+You can setup your [imconfig.h](https://github.com/ocornut/imgui/blob/master/imconfig.h) file with `IM_VEC2_CLASS_EXTRA`/`IM_VEC4_CLASS_EXTRA` macros to add implicit type conversions to our own maths types.
+This way you will be able to use your own types everywhere, e.g. passing `MyVector2` or `glm::vec2` to ImGui functions instead of `ImVec2`.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I interact with standard C++ types (such as std::string and std::vector)?
+- Being highly portable (backends/bindings for several languages, frameworks, programming styles, obscure or older platforms/compilers), and aiming for compatibility & performance suitable for every modern real-time game engine, Dear ImGui does not use any of std C++ types. We use raw types (e.g. char* instead of std::string) because they adapt to more use cases.
+- To use ImGui::InputText() with a std::string or any resizable string class, see [misc/cpp/imgui_stdlib.h](https://github.com/ocornut/imgui/blob/master/misc/cpp/imgui_stdlib.h).
+- To use combo boxes and list boxes with `std::vector` or any other data structure: the `BeginCombo()/EndCombo()` API
+lets you iterate and submit items yourself, so does the `ListBoxHeader()/ListBoxFooter()` API.
+Prefer using them over the old and awkward `Combo()/ListBox()` api.
+- Generally for most high-level types you should be able to access the underlying data type.
+You may write your own one-liner wrappers to facilitate user code (tip: add new functions in ImGui:: namespace from your code).
+- Dear ImGui applications often need to make intensive use of strings. It is expected that many of the strings you will pass
+to the API are raw literals (free in C/C++) or allocated in a manner that won't incur a large cost on your application.
+Please bear in mind that using `std::string` on applications with a large amount of UI may incur unsatisfactory performances.
+Modern implementations of `std::string` often include small-string optimization (which is often a local buffer) but those
+are not configurable and not the same across implementations.
+- If you are finding your UI traversal cost to be too large, make sure your string usage is not leading to an excessive amount
+of heap allocations. Consider using literals, statically sized buffers, and your own helper functions. A common pattern
+is that you will need to build lots of strings on the fly, and their maximum length can be easily scoped ahead.
+One possible implementation of a helper to facilitate printf-style building of strings: https://github.com/ocornut/Str
+This is a small helper where you can instance strings with configurable local buffers length. Many game engines will
+provide similar or better string helpers.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display custom shapes? (using low-level ImDrawList API)
+
+- You can use the low-level `ImDrawList` api to render shapes within a window.
+```cpp
+ImGui::Begin("My shapes");
+
+ImDrawList* draw_list = ImGui::GetWindowDrawList();
+
+// Get the current ImGui cursor position
+ImVec2 p = ImGui::GetCursorScreenPos();
+
+// Draw a red circle
+draw_list->AddCircleFilled(ImVec2(p.x + 50, p.y + 50), 30.0f, IM_COL32(255, 0, 0, 255));
+
+// Draw a 3 pixel thick yellow line
+draw_list->AddLine(ImVec2(p.x, p.y), ImVec2(p.x + 100.0f, p.y + 100.0f), IM_COL32(255, 255, 0, 255), 3.0f);
+
+// Advance the ImGui cursor to claim space in the window (otherwise the window will appear small and needs to be resized)
+ImGui::Dummy(ImVec2(200, 200));
+
+ImGui::End();
+```
+![ImDrawList usage](https://raw.githubusercontent.com/wiki/ocornut/imgui/tutorials/CustomRendering01.png)
+
+- Refer to "Demo > Examples > Custom Rendering" in the demo window and read the code of `ShowExampleAppCustomRendering()` in `imgui_demo.cpp` from more examples.
+- To generate colors: you can use the macro `IM_COL32(255,255,255,255)` to generate them at compile time, or use `ImGui::GetColorU32(IM_COL32(255,255,255,255))` or `ImGui::GetColorU32(ImVec4(1.0f,1.0f,1.0f,1.0f))` to generate a color that is multiplied by the current value of `style.Alpha`.
+- Math operators: if you have setup `IM_VEC2_CLASS_EXTRA` in `imconfig.h` to bind your own math types, you can use your own math types and their natural operators instead of ImVec2. ImVec2 by default doesn't export any math operators in the public API. You may use `#define IMGUI_DEFINE_MATH_OPERATORS` `#include "imgui.h"` to use our math operators, but instead prefer using your own math library and set it up in `imconfig.h`.
+- You can use `ImGui::GetBackgroundDrawList()` or `ImGui::GetForegroundDrawList()` to access draw lists which will be displayed behind and over every other Dear ImGui window (one bg/fg drawlist per viewport). This is very convenient if you need to quickly display something on the screen that is not associated with a Dear ImGui window.
+- You can also create your own empty window and draw inside it. Call Begin() with the NoBackground | NoDecoration | NoSavedSettings | NoInputs flags (The `ImGuiWindowFlags_NoDecoration` flag itself is a shortcut for NoTitleBar | NoResize | NoScrollbar | NoCollapse). Then you can retrieve the ImDrawList* via `GetWindowDrawList()` and draw to it in any way you like.
+- You can create your own ImDrawList instance. You'll need to initialize them with `ImGui::GetDrawListSharedData()`, or create your own instancing `ImDrawListSharedData`, and then call your renderer function with your own ImDrawList or ImDrawData data.
+- Looking for fun? The [ImDrawList coding party 2020](https://github.com/ocornut/imgui/issues/3606) thread is full of "don't do this at home" extreme uses of the ImDrawList API.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Fonts, Text
+
+### Q: How should I handle DPI in my application?
+
+The short answer is: obtain the desired DPI scale, load your fonts resized with that scale (always round down fonts size to the nearest integer), and scale your Style structure accordingly using `style.ScaleAllSizes()`.
+
+Your application may want to detect DPI change and reload the fonts and reset style between frames.
+
+Your ui code  should avoid using hardcoded constants for size and positioning. Prefer to express values as multiple of reference values such as `ImGui::GetFontSize()` or `ImGui::GetFrameHeight()`. So e.g. instead of seeing a hardcoded height of 500 for a given item/window, you may want to use `30*ImGui::GetFontSize()` instead.
+
+Down the line Dear ImGui will provide a variety of standardized reference values to facilitate using this.
+
+Applications in the `examples/` folder are not DPI aware partly because they are unable to load a custom font from the file-system (may change that in the future).
+
+The reason DPI is not auto-magically solved in stock examples is that we don't yet have a satisfying solution for the "multi-dpi" problem (using the `docking` branch: when multiple viewport windows are over multiple monitors using different DPI scales). The current way to handle this on the application side is:
+- Create and maintain one font atlas per active DPI scale (e.g. by iterating `platform_io.Monitors[]` before `NewFrame()`).
+- Hook `platform_io.OnChangedViewport()` to detect when a `Begin()` call makes a Dear ImGui window change monitor (and therefore DPI).
+- In the hook: swap atlas, swap style with correctly sized one, and remap the current font from one atlas to the other (you may need to maintain a remapping table of your fonts at varying DPI scales).
+
+This approach is relatively easy and functional but comes with two issues:
+- It's not possibly to reliably size or position a window ahead of `Begin()` without knowing on which monitor it'll land.
+- Style override may be lost during the `Begin()` call crossing monitor boundaries. You may need to do some custom scaling mumbo-jumbo if you want your `OnChangedViewport()` handler to preserve style overrides.
+
+Please note that if you are not using multi-viewports with multi-monitors using different DPI scales, you can ignore that and use the simpler technique recommended at the top.
+
+On Windows, in addition to scaling the font size (make sure to round to an integer) and using `style.ScaleAllSizes()`, you will need to inform Windows that your application is DPI aware. If this is not done, Windows will scale the application window and the UI text will be blurry. Potential solutions to indicate DPI awareness on Windows are:
+
+- For SDL: the flag `SDL_WINDOW_ALLOW_HIGHDPI` needs to be passed to `SDL_CreateWindow()``.
+- For GLFW: this is done automatically.
+- For other Windows projects with other backends, or wrapper projects:
+  - We provide a `ImGui_ImplWin32_EnableDpiAwareness()` helper method in the Win32 backend.
+  - Use an [application manifest file](https://learn.microsoft.com/en-us/windows/win32/hidpi/setting-the-default-dpi-awareness-for-a-process) to set the `<dpiAware>` property.
+
+### Q: How can I load a different font than the default?
+Use the font atlas to load the TTF/OTF file you want:
+
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels);
+io.Fonts->GetTexDataAsRGBA32() or GetTexDataAsAlpha8()
+```
+
+Default is ProggyClean.ttf, monospace, rendered at size 13, embedded in dear imgui's source code.
+
+(Tip: monospace fonts are convenient because they allow to facilitate horizontal alignment directly at the string level.)
+
+(Read the [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) file for more details about font loading.)
+
+New programmers: remember that in C/C++ and most programming languages if you want to use a
+backslash \ within a string literal, you need to write it double backslash "\\":
+
+```cpp
+io.Fonts->AddFontFromFileTTF("MyFolder\MyFont.ttf", size);  // WRONG (you are escaping the M here!)
+io.Fonts->AddFontFromFileTTF("MyFolder\\MyFont.ttf", size); // CORRECT (Windows only)
+io.Fonts->AddFontFromFileTTF("MyFolder/MyFont.ttf", size);  // ALSO CORRECT
+```
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I easily use icons in my application?
+The most convenient and practical way is to merge an icon font such as FontAwesome inside your
+main font. Then you can refer to icons within your strings.
+Read the [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) file for more details about icons font loading.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I load multiple fonts?
+
+Use the font atlas to pack them into a single texture. Read [docs/FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) for more details.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: How can I display and input non-Latin characters such as Chinese, Japanese, Korean, Cyrillic?
+When loading a font, pass custom Unicode ranges to specify the glyphs to load.
+
+```cpp
+// Add default Japanese ranges
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels, nullptr, io.Fonts->GetGlyphRangesJapanese());
+
+// Or create your own custom ranges (e.g. for a game you can feed your entire game script and only build the characters the game need)
+ImVector<ImWchar> ranges;
+ImFontGlyphRangesBuilder builder;
+builder.AddText("Hello world");                        // Add a string (here "Hello world" contains 7 unique characters)
+builder.AddChar(0x7262);                               // Add a specific character
+builder.AddRanges(io.Fonts->GetGlyphRangesJapanese()); // Add one of the default ranges
+builder.BuildRanges(&ranges);                          // Build the final result (ordered ranges with all the unique characters submitted)
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", 16.0f, nullptr, ranges.Data);
+```
+
+All your strings need to use UTF-8 encoding.
+You need to tell your compiler to use UTF-8, or in C++11 you can encode a string literal in UTF-8 by using the u8"hello" syntax.
+Specifying literal in your source code using a local code page (such as CP-923 for Japanese or CP-1251 for Cyrillic) will NOT work!
+See [About UTF-8 Encoding](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md#about-utf-8-encoding) section
+of [FONTS.md](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md) for details about UTF-8 Encoding.
+
+Text input: it is up to your application to pass the right character code by calling `io.AddInputCharacter()`.
+The applications in examples/ are doing that.
+Windows: you can use the WM_CHAR or WM_UNICHAR or WM_IME_CHAR message (depending if your app is built using Unicode or MultiByte mode).
+You may also use `MultiByteToWideChar()` or `ToUnicode()` to retrieve Unicode codepoints from MultiByte characters or keyboard state.
+Windows: if your language is relying on an Input Method Editor (IME), you can write your HWND to ImGui::GetMainViewport()->PlatformHandleRaw
+for the default implementation of io.SetPlatformImeDataFn() to set your Microsoft IME position correctly.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Concerns
+
+### Q: Who uses Dear ImGui?
+
+You may take a look at:
+
+- [Quotes](https://github.com/ocornut/imgui/wiki/Quotes)
+- [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui)
+- [Sponsors](https://github.com/ocornut/imgui/wiki/Sponsors)
+- [Gallery](https://github.com/ocornut/imgui/issues/6478)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Can you create elaborate/serious tools with Dear ImGui?
+
+Yes. People have written game editors, data browsers, debuggers, profilers, and all sorts of non-trivial tools with the library. In my experience, the simplicity of the API is very empowering. Your UI runs close to your live data. Make the tools always-on and everybody in the team will be inclined to create new tools (as opposed to more "offline" UI toolkits where only a fraction of your team effectively creates tools). The list of sponsors below is also an indicator that serious game teams have been using the library.
+
+Dear ImGui is very programmer centric and the immediate-mode GUI paradigm might require you to readjust some habits before you can realize its full potential. Dear ImGui is about making things that are simple, efficient, and powerful.
+
+Dear ImGui is built to be efficient and scalable toward the needs for AAA-quality applications running all day. The IMGUI paradigm offers different opportunities for optimization than the more typical RMGUI paradigm.
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Can you reskin the look of Dear ImGui?
+
+Somewhat. You can alter the look of the interface to some degree: changing colors, sizes, padding, rounding, and fonts. However, as Dear ImGui is designed and optimized to create debug tools, the amount of skinning you can apply is limited. There is only so much you can stray away from the default look and feel of the interface. Dear ImGui is NOT designed to create a user interface for games, although with ingenious use of the low-level API you can do it.
+
+A reasonably skinned application may look like (screenshot from [#2529](https://github.com/ocornut/imgui/issues/2529#issuecomment-524281119)):
+![minipars](https://user-images.githubusercontent.com/314805/63589441-d9794f00-c5b1-11e9-8d96-cfc1b93702f7.png)
+
+##### [Return to Index](#index)
+
+---
+
+### Q: Why using C++ (as opposed to C)?
+
+Dear ImGui takes advantage of a few C++ language features for convenience but nothing anywhere Boost insanity/quagmire. Dear ImGui doesn't use any C++ header file. Dear ImGui uses a very small subset of C++11 features. In particular, function overloading and default parameters are used to make the API easier to use and code terser. Doing so I believe the API is sitting on a sweet spot and giving up on those features would make the API more cumbersome. Other features such as namespace, constructors, and templates (in the case of the ImVector<> class) are also relied on as a convenience.
+
+There is an auto-generated [c-api for Dear ImGui (cimgui)](https://github.com/cimgui/cimgui) by Sonoro1234 and Stephan Dilly. It is designed for creating bindings to other languages. If possible, I would suggest using your target language functionalities to try replicating the function overloading and default parameters used in C++ else the API may be harder to use. Also see [Bindings](https://github.com/ocornut/imgui/wiki/Bindings) for various third-party bindings.
+
+##### [Return to Index](#index)
+
+---
+
+# Q&A: Community
+
+### Q: How can I help?
+- Businesses: please reach out to `omar AT dearimgui.com` if you work in a place using Dear ImGui! We can discuss ways for your company to fund development via invoiced technical support, maintenance, or sponsoring contacts. This is among the most useful thing you can do for Dear ImGui. With increased funding, we can hire more people to work on this project.
+- Individuals: you can support continued maintenance and development via PayPal donations. See [README](https://github.com/ocornut/imgui/blob/master/docs/README.md).
+- If you are experienced with Dear ImGui and C++, look at [GitHub Issues](https://github.com/ocornut/imgui/issues), [GitHub Discussions](https://github.com/ocornut/imgui/discussions), the [Wiki](https://github.com/ocornut/imgui/wiki), read [docs/TODO.txt](https://github.com/ocornut/imgui/blob/master/docs/TODO.txt), and see how you want to help and can help!
+- Disclose your usage of Dear ImGui via a dev blog post, a tweet, a screenshot, a mention somewhere, etc.
+You may post screenshots or links in the [gallery threads](https://github.com/ocornut/imgui/issues/6478). Visuals are ideal as they inspire other programmers. Disclosing your use of Dear ImGui helps the library grow credibility, and helps other teams and programmers with taking decisions.
+- If you have issues or if you need to hack into the library, even if you don't expect any support it is useful that you share your issues or sometimes incomplete PR.
+
+##### [Return to Index](#index)
+

ext/imgui/docs/FONTS.md

@@ -0,0 +1,502 @@
+_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/FONTS.md or view this file with any Markdown viewer)_
+
+## Dear ImGui: Using Fonts
+
+The code in imgui.cpp embeds a copy of 'ProggyClean.ttf' (by Tristan Grimmer),
+a 13 pixels high, pixel-perfect font used by default. We embed it in the source code so you can use Dear ImGui without any file system access. ProggyClean does not scale smoothly, therefore it is recommended that you load your own file when using Dear ImGui in an application aiming to look nice and wanting to support multiple resolutions.
+
+You may also load external .TTF/.OTF files.
+In the [misc/fonts/](https://github.com/ocornut/imgui/tree/master/misc/fonts) folder you can find a few suggested fonts, provided as a convenience.
+
+**Also read the FAQ:** https://www.dearimgui.com/faq (there is a Fonts section!)
+
+## Index
+- [Troubleshooting](#troubleshooting)
+- [How should I handle DPI in my application?](#how-should-i-handle-dpi-in-my-application)
+- [Fonts Loading Instructions](#fonts-loading-instructions)
+- [Loading Font Data from Memory](#loading-font-data-from-memory)
+- [Loading Font Data Embedded In Source Code](#loading-font-data-embedded-in-source-code)
+- [Using Icon Fonts](#using-icon-fonts)
+- [Using FreeType Rasterizer (imgui_freetype)](#using-freetype-rasterizer-imgui_freetype)
+- [Using Colorful Glyphs/Emojis](#using-colorful-glyphsemojis)
+- [Using Custom Glyph Ranges](#using-custom-glyph-ranges)
+- [Using Custom Colorful Icons](#using-custom-colorful-icons)
+- [About Filenames](#about-filenames)
+- [About UTF-8 Encoding](#about-utf-8-encoding)
+- [Debug Tools](#debug-tools)
+- [Credits/Licenses For Fonts Included In Repository](#creditslicenses-for-fonts-included-in-repository)
+- [Font Links](#font-links)
+
+---------------------------------------
+
+## Troubleshooting
+
+**A vast majority of font and text related issues encountered comes from 4 things:**
+
+### (1) Invalid filename due to use of `\` or unexpected working directory.
+
+See [About Filenames](#about-filenames). AddFontXXX functions should assert if the filename is incorrect.
+
+### (2) Invalid UTF-8 encoding of your non-ASCII strings.
+
+See [About UTF-8 Encoding](#about-utf-8-encoding). Use the encoding viewer to confirm encoding of string literal in your source code is correct.
+
+### (3) Missing glyph ranges.
+
+You need to load a font with explicit glyph ranges if you want to use non-ASCII characters. See [Fonts Loading Instructions](#fonts-loading-instructions). Use [Debug Tools](#debug-tools) confirm loaded fonts and loaded glyph ranges.
+
+This is a current constraint of Dear ImGui (which we will lift in the future): when loading a font you need to specify which characters glyphs to load.
+All loaded fonts glyphs are rendered into a single texture atlas ahead of time. Calling either of `io.Fonts->GetTexDataAsAlpha8()`, `io.Fonts->GetTexDataAsRGBA32()` or `io.Fonts->Build()` will build the atlas. This is generally called by the Renderer backend, e.g. `ImGui_ImplDX11_NewFrame()` calls it. **If you use custom glyphs ranges, make sure the array is persistent** and available during the calls to `GetTexDataAsAlpha8()/GetTexDataAsRGBA32()/Build()`.
+
+### (4) Font atlas texture fails to upload to GPU.
+
+This is often of byproduct of point 3. If you have large number of glyphs or multiple fonts, the texture may become too big for your graphics API. **The typical result of failing to upload a texture is if every glyph or everything appears as empty black or white rectangle.** Mind the fact that some graphics drivers have texture size limitation. If you are building a PC application, mind the fact that your users may use hardware with lower limitations than yours.
+
+Some solutions:
+- You may reduce oversampling, e.g. `font_config.OversampleH = 1`, this will half your texture size for a quality looss.
+  Note that while OversampleH = 2 looks visibly very close to 3 in most situations, with OversampleH = 1 the quality drop will be noticeable. Read about oversampling [here](https://github.com/nothings/stb/blob/master/tests/oversample).
+- Reduce glyphs ranges by calculating them from source localization data.
+  You can use the `ImFontGlyphRangesBuilder` for this purpose and rebuilding your atlas between frames when new characters are needed. This will be the biggest win!
+- Set `io.Fonts.Flags |= ImFontAtlasFlags_NoPowerOfTwoHeight;` to disable rounding the texture height to the next power of two.
+- Set `io.Fonts.TexDesiredWidth` to specify a texture width to reduce maximum texture height (see comment in `ImFontAtlas::Build()` function).
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## How should I handle DPI in my application?
+
+See [FAQ entry](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md#q-how-should-i-handle-dpi-in-my-application).
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Fonts Loading Instructions
+
+**Load default font:**
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontDefault();
+```
+
+**Load .TTF/.OTF file with:**
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels);
+```
+If you get an assert stating "Could not load font file!", your font filename is likely incorrect. Read [About filenames](#about-filenames) carefully.
+
+**Load multiple fonts:**
+```cpp
+// Init
+ImGuiIO& io = ImGui::GetIO();
+ImFont* font1 = io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels);
+ImFont* font2 = io.Fonts->AddFontFromFileTTF("anotherfont.otf", size_pixels);
+```
+
+In your application loop, select which font to use:
+```cpp
+ImGui::Text("Hello"); // use the default font (which is the first loaded font)
+ImGui::PushFont(font2);
+ImGui::Text("Hello with another font");
+ImGui::PopFont();
+```
+
+**For advanced options create a ImFontConfig structure and pass it to the AddFont() function (it will be copied internally):**
+```cpp
+ImFontConfig config;
+config.OversampleH = 2;
+config.OversampleV = 1;
+config.GlyphExtraSpacing.x = 1.0f;
+ImFont* font = io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, &config);
+```
+
+**Combine multiple fonts into one:**
+```cpp
+// Load a first font
+ImFont* font = io.Fonts->AddFontDefault();
+
+// Add character ranges and merge into the previous font
+// The ranges array is not copied by the AddFont* functions and is used lazily
+// so ensure it is available at the time of building or calling GetTexDataAsRGBA32().
+static const ImWchar icons_ranges[] = { 0xf000, 0xf3ff, 0 }; // Will not be copied by AddFont* so keep in scope.
+ImFontConfig config;
+config.MergeMode = true;
+io.Fonts->AddFontFromFileTTF("DroidSans.ttf", 18.0f, &config, io.Fonts->GetGlyphRangesJapanese()); // Merge into first font
+io.Fonts->AddFontFromFileTTF("fontawesome-webfont.ttf", 18.0f, &config, icons_ranges);             // Merge into first font
+io.Fonts->Build();
+```
+
+**Add a fourth parameter to bake specific font ranges only:**
+
+```cpp
+// Basic Latin, Extended Latin
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesDefault());
+
+// Default + Selection of 2500 Ideographs used by Simplified Chinese
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesChineseSimplifiedCommon());
+
+// Default + Hiragana, Katakana, Half-Width, Selection of 1946 Ideographs
+io.Fonts->AddFontFromFileTTF("font.ttf", size_pixels, nullptr, io.Fonts->GetGlyphRangesJapanese());
+```
+See [Using Custom Glyph Ranges](#using-custom-glyph-ranges) section to create your own ranges.
+
+**Example loading and using a Japanese font:**
+
+```cpp
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontFromFileTTF("NotoSansCJKjp-Medium.otf", 20.0f, nullptr, io.Fonts->GetGlyphRangesJapanese());
+```
+```cpp
+ImGui::Text(u8"こんにちは！テスト %d", 123);
+if (ImGui::Button(u8"ロード"))
+{
+    // do stuff
+}
+ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+```
+
+![sample code output](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/code_sample_02_jp.png)
+<br>_(settings: Dark style (left), Light style (right) / Font: NotoSansCJKjp-Medium, 20px / Rounding: 5)_
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Loading Font Data from Memory
+
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryTTF(data, data_size, size_pixels, ...);
+```
+
+IMPORTANT: `AddFontFromMemoryTTF()` by default transfer ownership of the data buffer to the font atlas, which will attempt to free it on destruction.
+This was to avoid an unnecessary copy, and is perhaps not a good API (a future version will redesign it).
+If you want to keep ownership of the data and free it yourself, you need to clear the `FontDataOwnedByAtlas` field:
+
+```cpp
+ImFontConfig font_cfg;
+font_cfg.FontDataOwnedByAtlas = false;
+ImFont* font = io.Fonts->AddFontFromMemoryTTF(data, data_size, size_pixels, &font_cfg);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Loading Font Data Embedded In Source Code
+
+- Compile and use [binary_to_compressed_c.cpp](https://github.com/ocornut/imgui/blob/master/misc/fonts/binary_to_compressed_c.cpp) to create a compressed C style array that you can embed in source code.
+- See the documentation in [binary_to_compressed_c.cpp](https://github.com/ocornut/imgui/blob/master/misc/fonts/binary_to_compressed_c.cpp) for instructions on how to use the tool.
+- You may find a precompiled version binary_to_compressed_c.exe for Windows inside the demo binaries package (see [README](https://github.com/ocornut/imgui/blob/master/docs/README.md)).
+- The tool can optionally output Base85 encoding to reduce the size of _source code_ but the read-only arrays in the actual binary will be about 20% bigger.
+
+Then load the font with:
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryCompressedTTF(compressed_data, compressed_data_size, size_pixels, ...);
+```
+or
+```cpp
+ImFont* font = io.Fonts->AddFontFromMemoryCompressedBase85TTF(compressed_data_base85, size_pixels, ...);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Icon Fonts
+
+Using an icon font (such as [FontAwesome](http://fontawesome.io) or [OpenFontIcons](https://github.com/traverseda/OpenFontIcons)) is an easy and practical way to use icons in your Dear ImGui application.
+A common pattern is to merge the icon font within your main font, so you can embed icons directly from your strings without having to change fonts back and forth.
+
+To refer to the icon UTF-8 codepoints from your C++ code, you may use those headers files created by Juliette Foucaut: https://github.com/juliettef/IconFontCppHeaders.
+
+So you can use `ICON_FA_SEARCH` as a string that will render as a "Search" icon.
+
+Example Setup:
+```cpp
+// Merge icons into default tool font
+#include "IconsFontAwesome.h"
+ImGuiIO& io = ImGui::GetIO();
+io.Fonts->AddFontDefault();
+
+ImFontConfig config;
+config.MergeMode = true;
+config.GlyphMinAdvanceX = 13.0f; // Use if you want to make the icon monospaced
+static const ImWchar icon_ranges[] = { ICON_MIN_FA, ICON_MAX_FA, 0 };
+io.Fonts->AddFontFromFileTTF("fonts/fontawesome-webfont.ttf", 13.0f, &config, icon_ranges);
+```
+Example Usage:
+```cpp
+// Usage, e.g.
+ImGui::Text("%s among %d items", ICON_FA_SEARCH, count);
+ImGui::Button(ICON_FA_SEARCH " Search");
+// C string _literals_ can be concatenated at compilation time, e.g. "hello" " world"
+// ICON_FA_SEARCH is defined as a string literal so this is the same as "A" "B" becoming "AB"
+```
+See Links below for other icons fonts and related tools.
+
+**Monospace Icons?**
+
+To make your icon look more monospace and facilitate alignment, you may want to set the ImFontConfig::GlyphMinAdvanceX value when loading an icon font.
+
+**Screenshot**
+
+Here's an application using icons ("Avoyd", https://www.avoyd.com):
+![avoyd](https://user-images.githubusercontent.com/8225057/81696852-c15d9e80-9464-11ea-9cab-2a4d4fc84396.jpg)
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using FreeType Rasterizer (imgui_freetype)
+
+- Dear ImGui uses imstb\_truetype.h to rasterize fonts (with optional oversampling). This technique and its implementation are not ideal for fonts rendered at small sizes, which may appear a little blurry or hard to read.
+- There is an implementation of the ImFontAtlas builder using FreeType that you can use in the [misc/freetype/](https://github.com/ocornut/imgui/tree/master/misc/freetype) folder.
+- FreeType supports auto-hinting which tends to improve the readability of small fonts.
+- Read documentation in the [misc/freetype/](https://github.com/ocornut/imgui/tree/master/misc/freetype) folder.
+- Correct sRGB space blending will have an important effect on your font rendering quality.
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Colorful Glyphs/Emojis
+
+- Rendering of colored emojis is supported by imgui_freetype with FreeType 2.10+.
+- You will need to load fonts with the `ImGuiFreeTypeBuilderFlags_LoadColor` flag.
+- Emojis are frequently encoded in upper Unicode layers (character codes >0x10000) and will need dear imgui compiled with `IMGUI_USE_WCHAR32`.
+- Not all types of color fonts are supported by FreeType at the moment.
+- Stateful Unicode features such as skin tone modifiers are not supported by the text renderer.
+
+![colored glyphs](https://user-images.githubusercontent.com/8225057/106171241-9dc4ba80-6191-11eb-8a69-ca1467b206d1.png)
+
+```cpp
+io.Fonts->AddFontFromFileTTF("../../../imgui_dev/data/fonts/NotoSans-Regular.ttf", 16.0f);
+static ImWchar ranges[] = { 0x1, 0x1FFFF, 0 };
+static ImFontConfig cfg;
+cfg.OversampleH = cfg.OversampleV = 1;
+cfg.MergeMode = true;
+cfg.FontBuilderFlags |= ImGuiFreeTypeBuilderFlags_LoadColor;
+io.Fonts->AddFontFromFileTTF("C:\\Windows\\Fonts\\seguiemj.ttf", 16.0f, &cfg, ranges);
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Custom Glyph Ranges
+
+You can use the `ImFontGlyphRangesBuilder` helper to create glyph ranges based on text input. For example: for a game where your script is known, if you can feed your entire script to it and only build the characters the game needs.
+```cpp
+ImVector<ImWchar> ranges;
+ImFontGlyphRangesBuilder builder;
+builder.AddText("Hello world");                        // Add a string (here "Hello world" contains 7 unique characters)
+builder.AddChar(0x7262);                               // Add a specific character
+builder.AddRanges(io.Fonts->GetGlyphRangesJapanese()); // Add one of the default ranges
+builder.BuildRanges(&ranges);                          // Build the final result (ordered ranges with all the unique characters submitted)
+
+io.Fonts->AddFontFromFileTTF("myfontfile.ttf", size_in_pixels, nullptr, ranges.Data);
+io.Fonts->Build();                                     // Build the atlas while 'ranges' is still in scope and not deleted.
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Using Custom Colorful Icons
+
+As an alternative to rendering colorful glyphs using imgui_freetype with `ImGuiFreeTypeBuilderFlags_LoadColor`, you may allocate your own space in the texture atlas and write yourself into it. **(This is a BETA api, use if you are familiar with dear imgui and with your rendering backend)**
+
+- You can use the `ImFontAtlas::AddCustomRect()` and `ImFontAtlas::AddCustomRectFontGlyph()` api to register rectangles that will be packed into the font atlas texture. Register them before building the atlas, then call Build()`.
+- You can then use `ImFontAtlas::GetCustomRectByIndex(int)` to query the position/size of your rectangle within the texture, and blit/copy any graphics data of your choice into those rectangles.
+- This API is beta because it is likely to change in order to support multi-dpi (multiple viewports on multiple monitors with varying DPI scale).
+
+#### Pseudo-code:
+```cpp
+// Add font, then register two custom 13x13 rectangles mapped to glyph 'a' and 'b' of this font
+ImFont* font = io.Fonts->AddFontDefault();
+int rect_ids[2];
+rect_ids[0] = io.Fonts->AddCustomRectFontGlyph(font, 'a', 13, 13, 13+1);
+rect_ids[1] = io.Fonts->AddCustomRectFontGlyph(font, 'b', 13, 13, 13+1);
+
+// Build atlas
+io.Fonts->Build();
+
+// Retrieve texture in RGBA format
+unsigned char* tex_pixels = nullptr;
+int tex_width, tex_height;
+io.Fonts->GetTexDataAsRGBA32(&tex_pixels, &tex_width, &tex_height);
+
+for (int rect_n = 0; rect_n < IM_ARRAYSIZE(rect_ids); rect_n++)
+{
+    int rect_id = rect_ids[rect_n];
+    if (const ImFontAtlasCustomRect* rect = io.Fonts->GetCustomRectByIndex(rect_id))
+    {
+        // Fill the custom rectangle with red pixels (in reality you would draw/copy your bitmap data here!)
+        for (int y = 0; y < rect->Height; y++)
+        {
+            ImU32* p = (ImU32*)tex_pixels + (rect->Y + y) * tex_width + (rect->X);
+            for (int x = rect->Width; x > 0; x--)
+                *p++ = IM_COL32(255, 0, 0, 255);
+        }
+    }
+}
+```
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## About Filenames
+
+**Please note that many new C/C++ users have issues loading their files _because the filename they provide is wrong_ due to incorrect assumption of what is the current directory.**
+
+Two things to watch for:
+
+(1) In C/C++ and most programming languages if you want to use a backslash `\` within a string literal, you need to write it double backslash `\\`. At it happens, Windows uses backslashes as a path separator, so be mindful.
+```cpp
+io.Fonts->AddFontFromFileTTF("MyFiles\MyImage01.jpg", ...);   // This is INCORRECT!!
+io.Fonts->AddFontFromFileTTF("MyFiles\\MyImage01.jpg", ...);  // This is CORRECT
+```
+In some situations, you may also use `/` path separator under Windows.
+
+(2) Make sure your IDE/debugger settings starts your executable from the right working (current) directory. In Visual Studio you can change your working directory in project `Properties > General > Debugging > Working Directory`. People assume that their execution will start from the root folder of the project, where by default it often starts from the folder where object or executable files are stored.
+```cpp
+io.Fonts->AddFontFromFileTTF("MyImage01.jpg", ...);       // Relative filename depends on your Working Directory when running your program!
+io.Fonts->AddFontFromFileTTF("../MyImage01.jpg", ...);    // Load from the parent folder of your Working Directory
+```
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## About UTF-8 Encoding
+
+**For non-ASCII characters display, a common user issue is not passing correctly UTF-8 encoded strings.**
+
+(1) We provide a function `ImGui::DebugTextEncoding(const char* text)` which you can call to verify the content of your UTF-8 strings.
+This is a convenient way to confirm that your encoding is correct.
+
+```cpp
+ImGui::SeparatorText("CORRECT");
+ImGui::DebugTextEncoding(u8"こんにちは");
+
+ImGui::SeparatorText("INCORRECT");
+ImGui::DebugTextEncoding("こんにちは");
+```
+![UTF-8 Encoding viewer](https://github.com/ocornut/imgui/assets/8225057/61c1696a-9a94-46c5-9627-cf91211111f0)
+
+You can also find this tool under `Metrics/Debuggers->Tools->UTF-8 Encoding viewer` if you want to paste from clipboard, but this won't validate the UTF-8 encoding done by your compiler.
+
+(2) To encode in UTF-8:
+
+There are also compiler-specific ways to enforce UTF-8 encoding by default:
+
+- Visual Studio compiler: `/utf-8` command-line flag.
+- Visual Studio compiler: `#pragma execution_character_set("utf-8")` inside your code.
+- Since May 2023 we have changed the Visual Studio projects of all our examples to use `/utf-8` ([see commit](https://github.com/ocornut/imgui/commit/513af1efc9080857bbd10000d98f98f2a0c96803)).
+
+Or, since C++11, you can use the `u8"my text"` syntax to encode literal strings as UTF-8. e.g.:
+```cpp
+ImGui::Text(u8"hello");
+ImGui::Text(u8"こんにちは");   // this will always be encoded as UTF-8
+ImGui::Text("こんにちは");     // the encoding of this is depending on compiler settings/flags and may be incorrect.
+```
+
+Since C++20, because the C++ committee hate its users, they decided to change the `u8""` syntax to not return `const char*` but a new type `const char_t*` which doesn't cast to `const char*`.
+Because of type usage of `u8""` in C++20 is a little more tedious:
+```cpp
+ImGui::Text((const char*)u8"こんにちは");
+```
+We suggest using a macro in your codebase:
+```cpp
+#define U8(_S)    (const char*)u8##_S
+ImGui::Text(U8("こんにちは"));
+```
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Debug Tools
+
+#### Metrics/Debugger->Fonts
+You can use the `Metrics/Debugger` window (available in `Demo>Tools`) to browse your fonts and understand what's going on if you have an issue. You can also reach it in `Demo->Tools->Style Editor->Fonts`. The same information are also available in the Style Editor under Fonts.
+
+![Fonts debugging](https://user-images.githubusercontent.com/8225057/135429892-0e41ef8d-33c5-4991-bcf6-f997a0bcfd6b.png)
+
+#### UTF-8 Encoding Viewer**
+You can use the `UTF-8 Encoding viewer` in `Metrics/Debugger` to verify the content of your UTF-8 strings. From C/C++ code, you can call `ImGui::DebugTextEncoding("my string");` function to verify that your UTF-8 encoding is correct.
+
+![UTF-8 Encoding viewer](https://user-images.githubusercontent.com/8225057/166505963-8a0d7899-8ee8-4558-abb2-1ae523dc02f9.png)
+
+##### [Return to Index](#index)
+
+---------------------------------------
+
+## Credits/Licenses For Fonts Included In Repository
+
+Some fonts files are available in the `misc/fonts/` folder:
+
+**Roboto-Medium.ttf**, by Christian Robetson
+<br>Apache License 2.0
+<br>https://fonts.google.com/specimen/Roboto
+
+**Cousine-Regular.ttf**, by Steve Matteson
+<br>Digitized data copyright (c) 2010 Google Corporation.
+<br>Licensed under the SIL Open Font License, Version 1.1
+<br>https://fonts.google.com/specimen/Cousine
+
+**DroidSans.ttf**, by Steve Matteson
+<br>Apache License 2.0
+<br>https://www.fontsquirrel.com/fonts/droid-sans
+
+**ProggyClean.ttf**, by Tristan Grimmer
+<br>MIT License
+<br>(recommended loading setting: Size = 13.0, GlyphOffset.y = +1)
+<br>http://www.proggyfonts.net/
+
+**ProggyTiny.ttf**, by Tristan Grimmer
+<br>MIT License
+<br>(recommended loading setting: Size = 10.0, GlyphOffset.y = +1)
+<br>http://www.proggyfonts.net/
+
+**Karla-Regular.ttf**, by Jonathan Pinhorn
+<br>SIL OPEN FONT LICENSE Version 1.1
+
+##### [Return to Index](#index)
+
+## Font Links
+
+#### ICON FONTS
+
+- C/C++ header for icon fonts (#define with code points to use in source code string literals) https://github.com/juliettef/IconFontCppHeaders
+- FontAwesome https://fortawesome.github.io/Font-Awesome
+- OpenFontIcons https://github.com/traverseda/OpenFontIcons
+- Google Icon Fonts https://design.google.com/icons/
+- Kenney Icon Font (Game Controller Icons) https://github.com/nicodinh/kenney-icon-font
+- IcoMoon - Custom Icon font builder https://icomoon.io/app
+
+#### REGULAR FONTS
+
+- Google Noto Fonts (worldwide languages) https://www.google.com/get/noto/
+- Open Sans Fonts https://fonts.google.com/specimen/Open+Sans
+- (Japanese) M+ fonts by Coji Morishita http://mplus-fonts.sourceforge.jp/mplus-outline-fonts/index-en.html
+
+#### MONOSPACE FONTS
+
+Pixel Perfect:
+- Proggy Fonts, by Tristan Grimmer http://www.proggyfonts.net or http://upperbounds.net
+- Sweet16, Sweet16 Mono, by Martin Sedlak (Latin + Supplemental + Extended A) https://github.com/kmar/Sweet16Font (also include an .inl file to use directly in dear imgui.)
+
+Regular:
+- Google Noto Mono Fonts https://www.google.com/get/noto/
+- Typefaces for source code beautification https://github.com/chrissimpkins/codeface
+- Programmation fonts http://s9w.github.io/font_compare/
+- Inconsolata http://www.levien.com/type/myfonts/inconsolata.html
+- Adobe Source Code Pro: Monospaced font family for ui & coding environments https://github.com/adobe-fonts/source-code-pro
+- Monospace/Fixed Width Programmer's Fonts http://www.lowing.org/fonts/
+
+Or use Arial Unicode or other Unicode fonts provided with Windows for full characters coverage (not sure of their licensing).
+
+##### [Return to Index](#index)

ext/imgui/docs/README.md

@@ -0,0 +1,218 @@
+Dear ImGui
+=====
+
+<center><b><i>"Give someone state and they'll have a bug one day, but teach them how to represent state in two separate locations that have to be kept in sync and they'll have bugs for a lifetime."</i></b></center> <a href="https://twitter.com/rygorous/status/1507178315886444544">-ryg</a>
+
+----
+
+[![Build Status](https://github.com/ocornut/imgui/workflows/build/badge.svg)](https://github.com/ocornut/imgui/actions?workflow=build) [![Static Analysis Status](https://github.com/ocornut/imgui/workflows/static-analysis/badge.svg)](https://github.com/ocornut/imgui/actions?workflow=static-analysis) [![Tests Status](https://github.com/ocornut/imgui_test_engine/workflows/tests/badge.svg)](https://github.com/ocornut/imgui_test_engine/actions?workflow=tests)
+
+<sub>(This library is available under a free and permissive license, but needs financial support to sustain its continued improvements. In addition to maintenance and stability there are many desirable features yet to be added. If your company is using Dear ImGui, please consider reaching out.)</sub>
+
+Businesses: support continued development and maintenance via invoiced sponsoring/support contracts:
+<br>&nbsp;&nbsp;_E-mail: contact @ dearimgui dot com_
+<br>Individuals: support continued development and maintenance [here](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=WGHNC6MBFLZ2S). Also see [Sponsors](https://github.com/ocornut/imgui/wiki/Sponsors) page.
+
+| [The Pitch](#the-pitch) - [Usage](#usage) - [How it works](#how-it-works) - [Releases & Changelogs](#releases--changelogs) - [Demo](#demo) - [Integration](#integration) |
+:----------------------------------------------------------: |
+| [Gallery](#gallery) - [Support, FAQ](#support-frequently-asked-questions-faq) -  [How to help](#how-to-help) - [Sponsors](https://github.com/ocornut/imgui/wiki/Sponsors) - [Credits](#credits) - [License](#license) |
+| [Wiki](https://github.com/ocornut/imgui/wiki) - [Languages & frameworks backends/bindings](https://github.com/ocornut/imgui/wiki/Bindings) - [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) - [User quotes](https://github.com/ocornut/imgui/wiki/Quotes) |
+
+### The Pitch
+
+Dear ImGui is a **bloat-free graphical user interface library for C++**. It outputs optimized vertex buffers that you can render anytime in your 3D-pipeline-enabled application. It is fast, portable, renderer agnostic, and self-contained (no external dependencies).
+
+Dear ImGui is designed to **enable fast iterations** and to **empower programmers** to create **content creation tools and visualization / debug tools** (as opposed to UI for the average end-user). It favors simplicity and productivity toward this goal and lacks certain features commonly found in more high-level libraries.
+
+Dear ImGui is particularly suited to integration in game engines (for tooling), real-time 3D applications, fullscreen applications, embedded applications, or any applications on console platforms where operating system features are non-standard.
+
+ - Minimize state synchronization.
+ - Minimize state storage on user side.
+ - Minimize setup and maintenance.
+ - Easy to use to create dynamic UI which are the reflection of a dynamic data set.
+ - Easy to use to create code-driven and data-driven tools.
+ - Easy to use to create ad hoc short-lived tools and long-lived, more elaborate tools.
+ - Easy to hack and improve.
+ - Portable, minimize dependencies, run on target (consoles, phones, etc.).
+ - Efficient runtime and memory consumption.
+ - Battle-tested, used by [many major actors in the game industry](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui).
+
+### Usage
+
+**The core of Dear ImGui is self-contained within a few platform-agnostic files** which you can easily compile in your application/engine. They are all the files in the root folder of the repository (imgui*.cpp, imgui*.h). **No specific build process is required**. You can add the .cpp files into your existing project. 
+
+**Backends for a variety of graphics API and rendering platforms** are provided in the [backends/](https://github.com/ocornut/imgui/tree/master/backends) folder, along with example applications in the [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder. You may also create your own backend. Anywhere where you can render textured triangles, you can render Dear ImGui.
+
+See the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide and [Integration](#integration) section of this document for more details.
+
+After Dear ImGui is set up in your application, you can use it from \_anywhere\_ in your program loop:
+```cpp
+ImGui::Text("Hello, world %d", 123);
+if (ImGui::Button("Save"))
+    MySaveFunction();
+ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+```
+![sample code output (dark, segoeui font, freetype)](https://user-images.githubusercontent.com/8225057/191050833-b7ecf528-bfae-4a9f-ac1b-f3d83437a2f4.png)
+![sample code output (light, segoeui font, freetype)](https://user-images.githubusercontent.com/8225057/191050838-8742efd4-504d-4334-a9a2-e756d15bc2ab.png)
+
+```cpp
+// Create a window called "My First Tool", with a menu bar.
+ImGui::Begin("My First Tool", &my_tool_active, ImGuiWindowFlags_MenuBar);
+if (ImGui::BeginMenuBar())
+{
+    if (ImGui::BeginMenu("File"))
+    {
+        if (ImGui::MenuItem("Open..", "Ctrl+O")) { /* Do stuff */ }
+        if (ImGui::MenuItem("Save", "Ctrl+S"))   { /* Do stuff */ }
+        if (ImGui::MenuItem("Close", "Ctrl+W"))  { my_tool_active = false; }
+        ImGui::EndMenu();
+    }
+    ImGui::EndMenuBar();
+}
+
+// Edit a color stored as 4 floats
+ImGui::ColorEdit4("Color", my_color);
+
+// Generate samples and plot them
+float samples[100];
+for (int n = 0; n < 100; n++)
+    samples[n] = sinf(n * 0.2f + ImGui::GetTime() * 1.5f);
+ImGui::PlotLines("Samples", samples, 100);
+
+// Display contents in a scrolling region
+ImGui::TextColored(ImVec4(1,1,0,1), "Important Stuff");
+ImGui::BeginChild("Scrolling");
+for (int n = 0; n < 50; n++)
+    ImGui::Text("%04d: Some text", n);
+ImGui::EndChild();
+ImGui::End();
+```
+![my_first_tool_v188](https://user-images.githubusercontent.com/8225057/191055698-690a5651-458f-4856-b5a9-e8cc95c543e2.gif)
+
+Dear ImGui allows you to **create elaborate tools** as well as very short-lived ones. On the extreme side of short-livedness: using the Edit&Continue (hot code reload) feature of modern compilers you can add a few widgets to tweak variables while your application is running, and remove the code a minute later! Dear ImGui is not just for tweaking values. You can use it to trace a running algorithm by just emitting text commands. You can use it along with your own reflection data to browse your dataset live. You can use it to expose the internals of a subsystem in your engine, to create a logger, an inspection tool, a profiler, a debugger, an entire game-making editor/framework, etc.
+
+### How it works
+
+The IMGUI paradigm through its API tries to minimize superfluous state duplication, state synchronization, and state retention from the user's point of view. It is less error-prone (less code and fewer bugs) than traditional retained-mode interfaces, and lends itself to creating dynamic user interfaces. Check out the Wiki's [About the IMGUI paradigm](https://github.com/ocornut/imgui/wiki#about-the-imgui-paradigm) section for more details.
+
+Dear ImGui outputs vertex buffers and command lists that you can easily render in your application. The number of draw calls and state changes required to render them is fairly small. Because Dear ImGui doesn't know or touch graphics state directly, you can call its functions  anywhere in your code (e.g. in the middle of a running algorithm, or in the middle of your own rendering process). Refer to the sample applications in the examples/ folder for instructions on how to integrate Dear ImGui with your existing codebase.
+
+_A common misunderstanding is to mistake immediate mode GUI for immediate mode rendering, which usually implies hammering your driver/GPU with a bunch of inefficient draw calls and state changes as the GUI functions are called. This is NOT what Dear ImGui does. Dear ImGui outputs vertex buffers and a small list of draw calls batches. It never touches your GPU directly. The draw call batches are decently optimal and you can render them later, in your app or even remotely._
+
+### Releases & Changelogs
+
+See [Releases](https://github.com/ocornut/imgui/releases) page for decorated Changelogs.
+Reading the changelogs is a good way to keep up to date with the things Dear ImGui has to offer, and maybe will give you ideas of some features that you've been ignoring until now!
+
+### Demo
+
+Calling the `ImGui::ShowDemoWindow()` function will create a demo window showcasing a variety of features and examples. The code is always available for reference in `imgui_demo.cpp`. [Here's how the demo looks](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v167/v167-misc.png).
+
+You should be able to build the examples from sources. If you don't, let us know! If you want to have a quick look at some Dear ImGui features, you can download Windows binaries of the demo app here:
+- [imgui-demo-binaries-20230704.zip](https://www.dearimgui.com/binaries/imgui-demo-binaries-20230704.zip) (Windows, 1.89.7, built 2023/07/04, master) or [older binaries](https://www.dearimgui.com/binaries).
+
+The demo applications are not DPI aware so expect some blurriness on a 4K screen. For DPI awareness in your application, you can load/reload your font at a different scale and scale your style with `style.ScaleAllSizes()` (see [FAQ](https://www.dearimgui.com/faq)).
+
+### Integration
+
+See the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide for details.
+
+On most platforms and when using C++, **you should be able to use a combination of the [imgui_impl_xxxx](https://github.com/ocornut/imgui/tree/master/backends) backends without modification** (e.g. `imgui_impl_win32.cpp` + `imgui_impl_dx11.cpp`). If your engine supports multiple platforms, consider using more imgui_impl_xxxx files instead of rewriting them: this will be less work for you, and you can get Dear ImGui running immediately. You can _later_ decide to rewrite a custom backend using your custom engine functions if you wish so.
+
+Integrating Dear ImGui within your custom engine is a matter of 1) wiring mouse/keyboard/gamepad inputs 2) uploading a texture to your GPU/render engine 3) providing a render function that can bind textures and render textured triangles, which is essentially what Backends are doing. The [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder is populated with applications doing just that: setting up a window and using backends. If you follow the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide it should in theory takes you less than an hour to integrate Dear ImGui.  **Make sure to spend time reading the [FAQ](https://www.dearimgui.com/faq), comments, and the examples applications!**
+
+Officially maintained backends/bindings (in repository):
+- Renderers: DirectX9, DirectX10, DirectX11, DirectX12, Metal, OpenGL/ES/ES2, SDL_Renderer, Vulkan, WebGPU.
+- Platforms: GLFW, SDL2/SDL3, Win32, Glut, OSX, Android.
+- Frameworks: Allegro5, Emscripten.
+
+[Third-party backends/bindings](https://github.com/ocornut/imgui/wiki/Bindings) wiki page:
+- Languages: C, C# and: Beef, ChaiScript, Crystal, D, Go, Haskell, Haxe/hxcpp, Java, JavaScript, Julia, Kotlin, Lobster, Lua, Odin, Pascal, PureBasic, Python, Ruby, Rust, Swift...
+- Frameworks: AGS/Adventure Game Studio, Amethyst, Blender, bsf, Cinder, Cocos2d-x, Diligent Engine, Flexium, GML/Game Maker Studio2, GLEQ, Godot, GTK3+OpenGL3, Irrlicht Engine, LÖVE+LUA, Magnum, Monogame, NanoRT, nCine, Nim Game Lib, Nintendo 3DS & Switch (homebrew), Ogre, openFrameworks, OSG/OpenSceneGraph, Orx, Photoshop, px_render, Qt/QtDirect3D, SDL_Renderer, SFML, Sokol, Unity, Unreal Engine 4, vtk, VulkanHpp, VulkanSceneGraph, Win32 GDI, WxWidgets.
+- Many bindings are auto-generated (by good old [cimgui](https://github.com/cimgui/cimgui) or newer/experimental [dear_bindings](https://github.com/dearimgui/dear_bindings)), you can use their metadata output to generate bindings for other languages.
+
+[Useful Extensions/Widgets](https://github.com/ocornut/imgui/wiki/Useful-Extensions) wiki page:
+- Automation/testing, Text editors, node editors, timeline editors, plotting, software renderers, remote network access, memory editors, gizmos, etc. One of the most notable and well supported extension is [ImPlot](https://github.com/epezent/implot).
+
+Also see [Wiki](https://github.com/ocornut/imgui/wiki) for more links and ideas.
+
+### Gallery
+
+For more user-submitted screenshots of projects using Dear ImGui, check out the [Gallery Threads](https://github.com/ocornut/imgui/issues/6478)!
+
+For a list of third-party widgets and extensions, check out the [Useful Extensions/Widgets](https://github.com/ocornut/imgui/wiki/Useful-Extensions) wiki page.
+
+|  |  |
+|--|--|
+| Custom engine [erhe](https://github.com/tksuoran/erhe) (docking branch)<BR>[![erhe](https://user-images.githubusercontent.com/8225057/190203358-6988b846-0686-480e-8663-1311fbd18abd.jpg)](https://user-images.githubusercontent.com/994606/147875067-a848991e-2ad2-4fd3-bf71-4aeb8a547bcf.png) | Custom engine for [Wonder Boy: The Dragon's Trap](http://www.TheDragonsTrap.com) (2017)<BR>[![the dragon's trap](https://user-images.githubusercontent.com/8225057/190203379-57fcb80e-4aec-4fec-959e-17ddd3cd71e5.jpg)](https://cloud.githubusercontent.com/assets/8225057/20628927/33e14cac-b329-11e6-80f6-9524e93b048a.png) |
+| Custom engine (untitled)<BR>[![editor white](https://user-images.githubusercontent.com/8225057/190203393-c5ac9f22-b900-4d1e-bfeb-6027c63e3d92.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v160/editor_white.png) | Tracy Profiler ([github](https://github.com/wolfpld/tracy))<BR>[![tracy profiler](https://user-images.githubusercontent.com/8225057/190203401-7b595f6e-607c-44d3-97ea-4c2673244dfb.jpg)](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v176/tracy_profiler.png) |
+
+### Support, Frequently Asked Questions (FAQ)
+
+See: [Frequently Asked Questions (FAQ)](https://github.com/ocornut/imgui/blob/master/docs/FAQ.md) where common questions are answered.
+
+See: [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) and [Wiki](https://github.com/ocornut/imgui/wiki) for many links, references, articles.
+
+See: [Articles about the IMGUI paradigm](https://github.com/ocornut/imgui/wiki#about-the-imgui-paradigm) to read/learn about the Immediate Mode GUI paradigm.
+
+See: [Upcoming Changes](https://github.com/ocornut/imgui/wiki/Upcoming-Changes).
+
+See: [Dear ImGui Test Engine + Test Suite](https://github.com/ocornut/imgui_test_engine) for Automation & Testing.
+
+Getting started? For first-time users having issues compiling/linking/running or issues loading fonts, please use [GitHub Discussions](https://github.com/ocornut/imgui/discussions). For other questions, bug reports, requests, feedback, you may post on [GitHub Issues](https://github.com/ocornut/imgui/issues). Please read and fill the New Issue template carefully.
+
+Private support is available for paying business customers (E-mail: _contact @ dearimgui dot com_).
+
+**Which version should I get?**
+
+We occasionally tag [Releases](https://github.com/ocornut/imgui/releases) (with nice releases notes) but it is generally safe and recommended to sync to latest `master` or `docking` branch. The library is fairly stable and regressions tend to be fixed fast when reported. Advanced users may want to use the `docking` branch with [Multi-Viewport](https://github.com/ocornut/imgui/issues/1542) and [Docking](https://github.com/ocornut/imgui/issues/2109) features. This branch is kept in sync with master regularly.
+
+**Who uses Dear ImGui?**
+
+See the [Quotes](https://github.com/ocornut/imgui/wiki/Quotes), [Sponsors](https://github.com/ocornut/imgui/wiki/Sponsors), and [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) Wiki pages for an idea of who is using Dear ImGui. Please add your game/software if you can! Also, see the [Gallery Threads](https://github.com/ocornut/imgui/issues/6478)!
+
+How to help
+-----------
+
+**How can I help?**
+
+- See [GitHub Forum/Issues](https://github.com/ocornut/imgui/issues) and [GitHub Discussions](https://github.com/ocornut/imgui/discussions).
+- You may help with development and submit pull requests! Please understand that by submitting a PR you are also submitting a request for the maintainer to review your code and then take over its maintenance forever. PR should be crafted both in the interest of the end-users and also to ease the maintainer into understanding and accepting it.
+- See [Help wanted](https://github.com/ocornut/imgui/wiki/Help-Wanted) on the [Wiki](https://github.com/ocornut/imgui/wiki/) for some more ideas.
+- Have your company financially support this project with invoiced sponsoring/support contracts or by buying a license for [Dear ImGui Test Engine](https://github.com/ocornut/imgui_test_engine) (please reach out: omar AT dearimgui DOT com).
+
+Sponsors
+--------
+
+Ongoing Dear ImGui development is and has been financially supported by users and private sponsors.
+<BR>Please see the **[detailed list of current and past Dear ImGui supporters](https://github.com/ocornut/imgui/wiki/Sponsors)** for details.
+<BR>From November 2014 to December 2019, ongoing development has also been financially supported by its users on Patreon and through individual donations.
+
+**THANK YOU to all past and present supporters for helping to keep this project alive and thriving!**
+
+Dear ImGui is using software and services provided free of charge for open source projects:
+- [PVS-Studio](https://www.viva64.com/en/b/0570/) for static analysis.
+- [GitHub actions](https://github.com/features/actions) for continuous integration systems.
+- [OpenCppCoverage](https://github.com/OpenCppCoverage/OpenCppCoverage) for code coverage analysis.
+
+Credits
+-------
+
+Developed by [Omar Cornut](https://www.miracleworld.net) and every direct or indirect [contributors](https://github.com/ocornut/imgui/graphs/contributors) to the GitHub. The early version of this library was developed with the support of [Media Molecule](https://www.mediamolecule.com) and first used internally on the game [Tearaway](https://tearaway.mediamolecule.com) (PS Vita).
+
+Recurring contributors (2022): Omar Cornut [@ocornut](https://github.com/ocornut), Rokas Kupstys [@rokups](https://github.com/rokups) (a good portion of work on automation system and regression tests now available in [Dear ImGui Test Engine](https://github.com/ocornut/imgui_test_engine)).
+
+Sponsoring, support contracts and other B2B transactions are hosted and handled by [Disco Hello](https://www.discohello.com).
+
+Omar: "I first discovered the IMGUI paradigm at [Q-Games](https://www.q-games.com) where Atman Binstock had dropped his own simple implementation in the codebase, which I spent quite some time improving and thinking about. It turned out that Atman was exposed to the concept directly by working with Casey. When I moved to Media Molecule I rewrote a new library trying to overcome the flaws and limitations of the first one I've worked with. It became this library and since then I have spent an unreasonable amount of time iterating and improving it."
+
+Embeds [ProggyClean.ttf](http://upperbounds.net) font by Tristan Grimmer (MIT license).
+<br>Embeds [stb_textedit.h, stb_truetype.h, stb_rect_pack.h](https://github.com/nothings/stb/) by Sean Barrett (public domain).
+
+Inspiration, feedback, and testing for early versions: Casey Muratori, Atman Binstock, Mikko Mononen, Emmanuel Briney, Stefan Kamoda, Anton Mikhailov, Matt Willis. Also thank you to everyone posting feedback, questions and patches on GitHub.
+
+License
+-------
+
+Dear ImGui is licensed under the MIT License, see [LICENSE.txt](https://github.com/ocornut/imgui/blob/master/LICENSE.txt) for more information.

ext/imgui/docs/TODO.txt

@@ -0,0 +1,347 @@
+dear imgui
+ISSUES & TODO LIST
+
+Issue numbers (#) refer to GitHub issues listed at https://github.com/ocornut/imgui/issues/XXXX
+THIS LIST IS NOT WELL MAINTAINED. MOST OF THE WORK HAPPENS ON GITHUB NOWADAYS.
+The list below consist mostly of ideas noted down before they are requested/discussed by users (at which point they usually exist on the github issue tracker).
+It's mostly a bunch of personal notes, probably incomplete. Feel free to query if you have any questions.
+
+ - doc: add a proper documentation system (maybe relying on automation? #435)
+ - doc: checklist app to verify backends/integration of imgui (test inputs, rendering, callback, etc.).
+ - doc/tips: tips of the day: website? applet in imgui_club?
+ - doc/wiki: work on the wiki https://github.com/ocornut/imgui/wiki
+
+ - window: preserve/restore relative focus ordering (persistent or not), and e.g. of multiple reappearing windows (#2304) -> also see docking reference to same #.
+ - window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
+ - window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
+ - window: auto-fit feedback loop when user relies on any dynamic layout (window width multiplier, column) appears weird to end-user. clarify.
+ - window: begin with *p_open == false could return false.
+ - window: get size/pos helpers given names (see discussion in #249)
+ - window: when window is very small, prioritize resize button over close button.
+ - window: double-clicking on title bar to minimize isn't consistent interaction, perhaps move to single-click on left-most collapse icon?
+ - window: expose contents size. (#1045)
+ - window: using SetWindowPos() inside Begin() and moving the window with the mouse reacts a very ugly glitch. We should just defer the SetWindowPos() call.
+ - window: GetWindowSize() returns (0,0) when not calculated? (#1045)
+ - window: investigate better auto-positioning for new windows.
+ - window: top most window flag? more z-order contrl? (#2574)
+ - window/size: manually triggered auto-fit (double-click on grip) shouldn't resize window down to viewport size?
+ - window/size: how to allow to e.g. auto-size vertically to fit contents, but be horizontally resizable? Assuming SetNextWindowSize() is modified to treat -1.0f on each axis as "keep as-is" (would be good but might break erroneous code): Problem is UpdateWindowManualResize() and lots of code treat (window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0) together.
+ - window/opt: freeze window flag: if not focused/hovered, return false, render with previous ImDrawList. and/or reduce refresh rate. -> this may require enforcing that it is illegal to submit contents if Begin returns false.
+ - window/child: background options for child windows, border option (disable rounding).
+ - window/child: allow resizing of child windows (possibly given min/max for each axis?.)
+ - window/child: allow SetNextWindowContentSize() to work on child windows.
+ - window/clipping: some form of clipping when DisplaySize (or corresponding viewport) is zero.
+ - window/tabbing: add a way to signify that a window or docked window requires attention (e.g. blinking title bar, trying to click behind a modal).
+ - window/id_stack: add e.g. window->GetIDFromPath() with support for leading / and ../ (#1390, #331) -> model from test engine.
+ ! scrolling: exposing horizontal scrolling with Shift+Wheel even when scrollbar is disabled expose lots of issues (#2424, #1463)
+ - scrolling: while holding down a scrollbar, try to keep the same contents visible (at least while not moving mouse)
+ - scrolling: allow immediately effective change of scroll after Begin() if we haven't appended items yet.
+ - scrolling: forward mouse wheel scrolling to parent window when at the edge of scrolling limits? (useful for listbox,tables?)
+ - scrolling/style: shadows on scrollable areas to denote that there is more contents (see e.g. DaVinci Resolve ui)
+
+ - drawdata: make it easy to deep-copy (or swap?) a full ImDrawData so user can easily save that data if they use threaded rendering. (e.g. #2646)
+ ! drawlist: add CalcTextSize() func to facilitate consistent code from user pov (currently need to use ImGui or ImFont alternatives!)
+ - drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command). (WIP branch)
+ - drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
+ - drawlist: non-AA strokes have gaps between points (#593, #288), glitch especially on RenderCheckmark() and ColorPicker4().
+ - drawlist: callback: add an extra void* in ImDrawCallback to allow passing render-local data to the callback (would break API).
+ - drawlist: AddRect vs AddLine position confusing (#2441)
+ - drawlist/opt: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding. (#1962)
+ - drawlist/opt: AddRect() axis aligned pixel aligned (no-aa) could use 8 triangles instead of 16 and no normal calculation.
+ - drawlist/opt: thick AA line could be doable in same number of triangles as 1.0 AA line by storing gradient+full color in atlas.
+
+ - items: IsItemHovered() info stored in a stack? so that 'if TreeNode() { Text; TreePop; } if IsHovered' return the hover state of the TreeNode?
+
+ - widgets: display mode: widget-label, label-widget (aligned on column or using fixed size), label-newline-tab-widget etc. (#395)
+ - widgets: clean up widgets internal toward exposing everything and stabilizing imgui_internals.h.
+ - widgets: add always-allow-overlap mode. This should perhaps be the default? one problem is that highlight after mouse-wheel scrolling gets deferred, makes scrolling more flickery.
+ - widgets: start exposing PushItemFlag() and ImGuiItemFlags
+ - widgets: alignment options in style (e.g. center Selectable, Right-Align within Button, etc.) #1260
+ - widgets: activate by identifier (trigger button, focus given id)
+ - widgets: custom glyph/shapes replacements for stock sapes. (also #6090 #2431 #2235 #6517)
+ - widgets: coloredit: keep reporting as active when picker is on?
+ - widgets: group/scalarn functions: expose more per-component information. e.g. store NextItemData.ComponentIdx set by scalarn function, groups can expose them back somehow.
+ - selectable: using (size.x == 0.0f) and (SelectableTextAlign.x > 0.0f) followed by SameLine() is currently not supported.
+ - selectable: generic BeginSelectable()/EndSelectable() mechanism. (work out alongside range-select branch)
+ - selectable: a way to visualize partial/mixed selection (e.g. parent tree node has children with mixed selection)
+
+ - input text: clean up the mess caused by converting UTF-8 <> wchar. the code is rather inefficient right now and super fragile. (WIP branch)
+ - input text: preserve scrolling when unfocused?
+ - input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
+ - input text: expose CursorPos in char filter event (#816)
+ - input text: try usage idiom of using InputText with data only exposed through get/set accessors, without extraneous copy/alloc. (#3009)
+ - input text: access public fields via a non-callback API e.g. InputTextGetState("xxx") that may return nullptr if not active (available in internals)
+ - input text: flag to disable live update of the user buffer (also applies to float/int text input) (#701)
+ - input text: hover tooltip could show unclamped text
+ - input text: support for INSERT key to toggle overwrite mode. currently disabled because stb_textedit behavior is unsatisfactory on multi-line. (#2863)
+ - input text: option to Tab after an Enter validation.
+ - input text: add ImGuiInputTextFlags_EnterToApply? (off #218)
+ - input text: easier ways to update buffer (from source char*) while owned. preserve some sort of cursor position for multi-line text.
+ - input text: add discard flag (e.g. ImGuiInputTextFlags_DiscardActiveBuffer) or make it easier to clear active focus for text replacement during edition (#725)
+ - input text: display bug when clicking a drag/slider after an input text in a different window has all-selected text (order dependent). actually a very old bug but no one appears to have noticed it.
+ - input text: allow centering/positioning text so that ctrl+clicking Drag or Slider keeps the textual value at the same pixel position.
+ - input text: decorrelate display layout from inputs with custom template - e.g. what's the easiest way to implement a nice IP/Mac address input editor?
+ - input text: global callback system so user can plug in an expression evaluator easily. (#1691)
+ - input text: force scroll to end or scroll to a given line/contents (so user can implement a log or a search feature)
+ - input text: a way to preview completion (e.g. disabled text completing from the cursor)
+ - input text: a side bar that could e.g. preview where errors are. probably left to the user to draw but we'd need to give them the info there.
+ - input text: a way for the user to provide syntax coloring.
+ - input text: Shift+TAB with ImGuiInputTextFlags_AllowTabInput could eat preceding blanks, up to tab_count.
+ - input text multi-line: don't directly call AddText() which does an unnecessary vertex reserve for character count prior to clipping. and/or more line-based clipping to AddText(). and/or reorganize TextUnformatted/RenderText for more efficiency for large text (e.g TextUnformatted could clip and log separately, etc).
+ - input text multi-line: support for copy/cut without selection (copy/cut current line?)
+ - input text multi-line: line numbers? status bar? (follow up on #200)
+ - input text multi-line: behave better when user changes input buffer while editing is active (even though it is illegal behavior). namely, the change of buffer can create a scrollbar glitch (#725)
+ - input text multi-line: better horizontal scrolling support (#383, #1224)
+ - input text multi-line: single call to AddText() should be coarse clipped on InputTextEx() end.
+ - input number: optional range min/max for Input*() functions
+ - input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
+ - input number: use mouse wheel to step up/down
+
+ - layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
+ - layout, font: horizontal tab support, A) text mode: forward only tabs (e.g. every 4 characters/N pixels from pos x1), B) manual mode: explicit tab stops acting as mini columns, no clipping (for menu items, many kind of uses, also vaguely relate to #267, #395)
+ - layout: horizontal layout helper (#97)
+ - layout: horizontal flow until no space left (#404)
+ - layout: more generic alignment state (left/right/centered) for single items?
+ - layout: clean up the InputFloatN/SliderFloatN/ColorEdit4 layout code. item width should include frame padding.
+ - layout: vertical alignment of mixed height items (e.g. buttons) within a same line (#1284)
+ - layout: null layout mode were items are not rendered but user can query GetItemRectMin()/Max/Size.
+ - layout: (R&D) local multi-pass layout mode.
+ - layout: (R&D) bind authored layout data (created by an off-line tool), items fetch their pos/size at submission, self-optimize data structures to stable linear access.
+
+ - tables: see https://github.com/ocornut/imgui/issues/2957#issuecomment-569726095
+
+ - group: BeginGroup() needs a border option. (~#1496)
+ - group: IsItemHovered() after EndGroup() covers whole AABB rather than the intersection of individual items. Is that desirable?
+ - group: merge deactivation/activation within same group (fwd WasEdited flag). (#2550)
+
+!- color: the color conversion helpers/types are a mess and needs sorting out.
+ - color: (api breaking) ImGui::ColorConvertXXX functions should be loose ImColorConvertXX to match imgui_internals.h
+
+ - plot: full featured plot/graph api w/ scrolling, zooming etc. --> ImPlot
+ - (plot: deleted all other todo lines on 2023-06-28)
+
+ - clipper: ability to disable the clipping through a simple flag/bool.
+ - clipper: ability to run without knowing full count in advance.
+ - clipper: horizontal clipping support. (#2580)
+
+ - separator: expose flags (#759)
+ - separator: take indent into consideration (optional)
+ - separator: width, thickness, centering (#1643, #2657)
+ - splitter: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)
+
+ - docking: merge docking branch (#2109)
+
+ - tabs: "there is currently a problem because TabItem() will try to submit their own tooltip after 0.50 second, and this will have the effect of making your tooltip flicker once." -> tooltip priority work (WIP branch)
+ - tabs: make EndTabBar fail if users doesn't respect BeginTabBar return value, for consistency/future-proofing.
+ - tabs: persistent order/focus in BeginTabBar() api (#261, #351)
+ - tabs: explicit api (even if internal) to cleanly manipulate tab order.
+
+ - image/image button: misalignment on padded/bordered button?
+ - image/image button: parameters are confusing, image() has tint_col,border_col whereas imagebutton() has bg_col/tint_col. Even thou they are different parameters ordering could be more consistent. can we fix that?
+ - slider: allow using the [-]/[+] buttons used by InputFloat()/InputInt()
+ - slider: add dragging-based widgets to edit values with mouse (on 2 axises), saving screen real-estate.
+ - slider: tint background based on value (e.g. v_min -> v_max, or use 0.0f either side of the sign)
+ - slider: relative dragging? + precision dragging
+ - slider: step option (#1183)
+ - slider: style: fill % of the bar instead of positioning a drag.
+ - knob: rotating knob widget (#942)
+ - drag float: support for reversed drags (min > max) (removed is_locked, also see fdc526e)
+ - drag float: up/down axis
+ - drag float: power != 0.0f with current value being outside the range keeps the value stuck.
+ - drag float: added leeway on edge (e.g. a few invisible steps past the clamp limits)
+
+ - combo: use clipper.
+ - combo: a way/helper to customize the combo preview (#1658) -> experimental BeginComboPreview()
+ - combo/listbox: keyboard control. need InputText-like non-active focus + key handling. considering keyboard for custom listbox (pr #203)
+ - listbox: multiple selection (WIP range-select branch)
+ - listbox: unselect option (#1208)
+ - listbox: make it easier/more natural to implement range-select (need some sort of info/ref about the last clicked/focused item that user can translate to an index?) (WIP range-select branch)
+ - listbox: user may want to initial scroll to focus on the one selected value?
+ - listbox: disable capturing mouse wheel if the listbox has no scrolling. (#1681)
+ - listbox: scrolling should track modified selection.
+ - listbox: future api should allow to enable horizontal scrolling (#2510)
+
+!- popups/menus: clarify usage of popups id, how MenuItem/Selectable closing parent popups affects the ID, etc. this is quite fishy needs improvement! (#331, #402)
+ - modals: make modal title bar blink when trying to click outside the modal
+ - modals: technically speaking, we could make Begin() with ImGuiWindowFlags_Modal work without involving popup. May help untangle a few things, as modals are more like regular windows than popups.
+ - popups: if the popup functions took explicit ImGuiID it would allow the user to manage the scope of those ID. (#331)
+ - popups: clicking outside (to close popup) and holding shouldn't drag window below.
+ - popups: add variant using global identifier similar to Begin/End (#402)
+ - popups: border options. richer api like BeginChild() perhaps? (#197)
+ - popups/modals: although it is sometimes convenient that popups/modals lifetime is owned by imgui, we could also a bool-owned-by-user api as long as Begin() return value testing is enforced.
+
+ - tooltip: drag and drop with tooltip near monitor edges lose/changes its last direction instead of locking one. The drag and drop tooltip should always follow without changing direction.
+ - tooltip: allow to set the width of a tooltip to allow TextWrapped() etc. while keeping the height automatic.
+ - tooltip: drag tooltip hovering over source widget with IsItemHovered/SetTooltip flickers (WIP branch)
+
+ - status-bar: add a per-window status bar helper similar to what menu-bar does. generalize concept of layer0 rect in window (can make _MenuBar window flag obsolete too).
+ - shortcuts: local-style shortcut api, e.g. parse "&Save"
+ - shortcuts,menus: global-style shortcut api e.g. "Save (CTRL+S)" -> explicit flag for recursing into closed menu
+ - shortcuts: programmatically access shortcuts "Focus("&Save"))
+ - menus: menu-bar: main menu-bar could affect clamping of windows position (~ akin to modifying DisplayMin)
+ - menus: hovering from menu to menu on a menu-bar has 1 frame without any menu, which is a little annoying. ideally either 0 either longer.
+ - menus: would be nice if the Selectable() supported horizontal alignment (must be given the equivalent of WorkRect.Max.x matching the position of the shortcut column)
+
+ - tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
+ - tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?
+ - tree node / selectable render mismatch which is visible if you use them both next to each other (e.g. cf. property viewer)
+ - tree node: tweak color scheme to distinguish headers from selected tree node (#581)
+ - tree node: leaf/non-leaf highlight mismatch.
+ - tree node: flag to disable formatting and/or detect "%s"
+ - tree node/opt: could avoid formatting when clipped (flag assuming we don't care about width/height, assume single line height? format only %s/%c to be able to count height?)
+
+ - settings: write more decent code to allow saving/loading new fields: columns, selected tree nodes?
+ - settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
+ - settings/persistence: helpers to make TreeNodeBehavior persist (even during dev!) - may need to store some semantic and/or data type in ImGuiStoragePair
+
+ - style: better default styles. (#707)
+ - style: PushStyleVar: allow direct access to individual float X/Y elements.
+ - style: add a highlighted text color (for headers, etc.)
+ - style: border types: out-screen, in-screen, etc. (#447)
+ - style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
+ - style: a concept of "compact style" that the end-user can easily rely on (e.g. PushStyleCompact()?) that maps to other settings? avoid implementing duplicate helpers such as SmallCheckbox(), etc.
+ - style: try to make PushStyleVar() more robust to incorrect parameters (to be more friendly to edit & continues situation).
+ - style: global scale setting.
+ - style: FramePadding could be different for up vs down (#584)
+ - style: WindowPadding needs to be EVEN as the 0.5 multiplier used on this value probably have a subtle effect on clip rectangle
+ - style: have a more global HSV setter (e.g. alter hue on all elements). consider replacing active/hovered by offset in HSV space? (#438, #707, #1223)
+ - style: gradients fill (#1223) ~ 2 bg colors for each fill? tricky with rounded shapes and using textures for corners.
+ - style editor: color child window height expressed in multiple of line height.
+
+ - log: improve logging of ArrowButton, ListBox, TabItem
+ - log: carry on indent / tree depth when opening a child window
+ - log: enabling log ends up pushing and growing vertices buffers because we don't distinguish layout vs render clipping
+ - log: have more control over the log scope (e.g. stop logging when leaving current tree node scope)
+ - log: be able to log anything (e.g. right-click on a window/tree-node, shows context menu? log into tty/file/clipboard)
+ - log: let user copy any window content to clipboard easily (CTRL+C on windows? while moving it? context menu?). code is commented because it fails with multiple Begin/End pairs.
+ - log: obsolete LogButtons().... (was: LogButtons() options for specifying depth and/or hiding depth slider)
+
+ - filters: set a current filter that certains items (e.g. tree node) can automatically query to hide themselves
+ - filters: handle wild-cards (with implicit leading/trailing *), reg-exprs
+ - filters: fuzzy matches (may use code at blog.forrestthewoods.com/4cffeed33fdb)
+
+ - drag and drop: focus drag target window on hold (even without open)
+ - drag and drop: releasing a drop shows the "..." tooltip for one frame - since e13e598 (#1725)
+ - drag and drop: drag source on a group object (would need e.g. an invisible button covering group in EndGroup) https://twitter.com/paniq/status/1121446364909535233
+ - drag and drop: have some way to know when a drag begin from BeginDragDropSource() pov. (see 2018/01/11 post in #143)
+ - drag and drop: allow preview tooltip to be submitted from a different place than the drag source. (#1725)
+ - drag and drop: make it easier and provide a demo to have tooltip both are source and target site, with a more detailed one on target site (tooltip ordering problem)
+ - drag and drop: demo with reordering nodes (in a list, or a tree node). (#143)
+ - drag and drop: test integrating with os drag and drop (make it easy to do a naive WM_DROPFILE integration)
+ - drag and drop: allow for multiple payload types. (#143)
+ - drag and drop: make payload optional? payload promise? (see 2018/01/11 post in #143)
+ - drag and drop: (#143) "both an in-process pointer and a promise to generate a serialized version, for whether the drag ends inside or outside the same process"
+ - drag and drop: feedback when hovering a region blocked by modal (mouse cursor "NO"?)
+
+ - markup: simple markup language for color change? (#902, #3130)
+
+ - text: selectable text (for copy) as a generic feature (ItemFlags?)
+ - text: proper alignment options in imgui_internal.h
+ - text: provided a framed text helper, e.g. https://pastebin.com/1Laxy8bT
+ - text: refactor TextUnformatted (or underlying function) to more explicitly request if we need width measurement or not
+ - text/layout/tabs: \t pulling position from base pos + step, or offset array (e.g. could be used in text edit, menus for simple icon+text alignment, etc.)
+ - text link/url button: underlined. should api expose an ID or use text contents as ID? which colors enum to use?
+ - text/wrapped: should be a more first-class citizen, e.g. wrapped text within a Selectable with known width.
+ - text/wrapped: custom separator for text wrapping. (#3002)
+ - text/wrapped: figure out better way to use TextWrapped() in an always auto-resize context (tooltip, etc.) (#249)
+
+ - font: arbitrary line spacing. (#2945)
+ - font: MergeMode: flags to select overwriting or not (this is now very easy with refactored ImFontAtlasBuildWithStbTruetype)
+ - font: free the Alpha buffer if user only requested RGBA.
+!- font: better CalcTextSizeA() API, at least for simple use cases. current one is horrible (perhaps have simple vs extended versions).
+ - font: for the purpose of RenderTextEllipsis(), it might be useful that CalcTextSizeA() can ignore the trailing padding?
+ - font: a CalcTextHeight() helper could run faster than CalcTextSize().y
+ - font: enforce monospace through ImFontConfig (for icons?) + create dual ImFont output from same input, reusing rasterized data but with different glyphs/AdvanceX
+ - font: finish CustomRectRegister() to allow mapping Unicode codepoint to custom texture data
+ - font: remove ID from CustomRect registration, it seems unnecessary!
+ - font: make it easier to submit own bitmap font (same texture, another texture?). (#2127, #2575)
+ - font: PushFontSize API (#1018)
+ - font: MemoryTTF taking ownership confusing/not obvious, maybe default should be opposite?
+ - font: storing MinAdvanceX per font would allow us to skip calculating line width (under a threshold of character count) in loops looking for block width
+ - font/demo: add tools to show glyphs used by a text blob, display U16 value, list missing glyphs.
+ - font/demo: demonstrate use of ImFontGlyphRangesBuilder.
+ - font/atlas: add a missing Glyphs.reserve()
+ - font/atlas: incremental updates
+ - font/atlas: dynamic font atlas to avoid baking huge ranges into bitmap and make scaling easier.
+ - font/draw: vertical and/or rotated text renderer (#705) - vertical is easier clipping wise
+ - font/draw: need to be able to specify wrap start position.
+ - font/draw: better reserve policy for large horizontal block of text (shouldn't reserve for all clipped lines). also see #3349.
+ - font/draw: fix for drawing 16k+ visible characters in same call.
+ - font/draw: underline, squiggle line rendering helpers.
+ - font: optimization: for monospace font (like the default one) we can trim IndexXAdvance as long as trailing value is == FallbackXAdvance (need to make sure TAB is still correct), would save on cache line.
+ - font: add support for kerning, probably optional. A) perhaps default to (32..128)^2 matrix ~ 9K entries = 36KB, then hash for non-ascii?. B) or sparse lookup into per-char list?
+ - font: add a simpler CalcTextSizeA() api? current one ok but not welcome if user needs to call it directly (without going through ImGui::CalcTextSize)
+ - font: fix AddRemapChar() to work before atlas  has been built.
+ - font: (api breaking) remove "TTF" from symbol names. also because it now supports OTF.
+ - font/opt: Considering storing standalone AdvanceX table as 16-bit fixed point integer?
+ - font/opt: Glyph currently 40 bytes (2+9*4). Consider storing UV as 16-bits integer? (->32 bytes). X0/Y0/X1/Y1 as 16 fixed-point integers? Or X0/Y0 as float and X1/Y1 as fixed8_8?
+
+ - nav: visual feedback on button press.
+ - nav: some features such as PageUp/Down/Home/End should probably work without ImGuiConfigFlags_NavEnableKeyboard? (where do we draw the line? how about CTRL+Tab)
+ ! nav: never clear NavId on some setup (e.g. gamepad centric)
+ - nav: there's currently no way to completely clear focus with the keyboard. depending on patterns used by the application to dispatch inputs, it may be desirable.
+ - nav: Home/End behavior when navigable item is not fully visible at the edge of scrolling? should be backtrack to keep item into view?
+ - nav: NavScrollToBringItemIntoView() with item bigger than view should focus top-right? Repro: using Nav in "About Window"
+ - nav: wrap around logic to allow e.g. grid based layout (pressing NavRight on the right-most element would go to the next row, etc.). see internal's NavMoveRequestTryWrapping().
+ - nav: patterns to make it possible for arrows key to update selection (see JustMovedTo in range_select branch)
+ - nav: restore/find nearest NavId when current one disappear (e.g. pressed a button that disappear, or perhaps auto restoring when current button change name)
+ - nav: SetItemDefaultFocus() level of priority, so widget like Selectable when inside a popup could claim a low-priority default focus on the first selected iem
+ - nav: NavFlattened: init requests don't work properly on flattened siblings.
+ - nav: NavFlattened: pageup/pagedown/home/end don't work properly on flattened siblings.
+ - nav: NavFlattened: ESC on a flattened child should select something.
+ - nav: NavFlattened: broken: in typical usage scenario, the items of a fully clipped child are currently not considered to enter into a NavFlattened child.
+ - nav: NavFlattened: cannot access menu-bar of a flattened child window with Alt/menu key (not a very common use case..).
+ - nav: simulate right-click or context activation? (SHIFT+F10, keyboard Menu key?)
+ - nav/popup: esc/enter default behavior for popups, e.g. be able to mark an "ok" or "cancel" button that would get triggered by those keys, default validation button, etc.
+ - nav/treenode: left within a tree node block as a fallback (ImGuiTreeNodeFlags_NavLeftJumpsBackHere by default?)
+ - nav/menus: pressing left-right on a vertically clipped menu bar tends to jump to the collapse/close buttons.
+ - nav/menus: allow pressing Menu to leave a sub-menu.
+ - nav/menus: a way to access the main menu bar with Alt? (currently needs CTRL+TAB) or last focused window menu bar?
+ - nav/menus: when using the main menu bar, even though we restore focus after, the underlying window loses its title bar highlight during menu manipulation. could we prevent it?
+ - nav/menus: main menu bar currently cannot restore a nullptr focus. Could save NavWindow at the time of being focused, similarly to what popup do?
+ - nav/menus: Alt,Up could open the first menu (e.g. "File") currently it tends to nav into the window/collapse menu. Do do that we would need custom transition?
+ - nav/windowing: when CTRL+Tab/windowing is active, the HoveredWindow detection doesn't take account of the window display re-ordering.
+ - nav/windowing: Resizing window will currently fail with certain types of resizing constraints/callback applied
+ - focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
+
+ - inputs: support track pad style scrolling & slider edit.
+ - inputs/io: backspace and arrows in the context of a text input could use system repeat rate.
+ - inputs/io: clarify/standardize/expose repeat rate and repeat delays (#1808)
+ - inputs/scrolling: support for smooth scrolling (#2462, #2569)
+
+ - misc: idle: expose "woken up" boolean (set by inputs) and/or animation time (for cursor blink) for backend to be able stop refreshing easily.
+ - misc: idle: if cursor blink if the _only_ visible animation, core imgui could rewrite vertex alpha to avoid CPU pass on ImGui:: calls.
+ - misc: idle: if cursor blink if the _only_ visible animation, could even expose a dirty rectangle that optionally can be leverage by some app to render in a smaller viewport, getting rid of much pixel shading cost.
+ - misc: no way to run a root-most GetID() with ImGui:: api since there's always a Debug window in the stack. (mentioned in #2960)
+ - misc: make the ImGuiCond values linear (non-power-of-two). internal storage for ImGuiWindow can use integers to combine into flags (Why?)
+ - misc: PushItemFlag(): add a flag to disable keyboard capture when used with mouse? (#1682)
+ - misc: use more size_t in public api?
+ - misc: possible compile-time support for string view/range instead of char* would e.g. facilitate usage with Rust (#683, #3038, WIP string_view branch)
+ - misc: possible compile-time support for wchar_t instead of char*?
+
+ - demo: demonstrate using PushStyleVar() in more details.
+ - demo: add vertical separator demo
+ - demo: add virtual scrolling example?
+ - demo: demonstrate Plot offset
+ - demo: window size constraint: square demo is broken when resizing from edges (#1975), would need to rework the callback system to solve this
+
+ - examples: window minimize, maximize (#583)
+ - examples: provide a zero frame-rate/idle example.
+ - examples: dx11/dx12: try to use new swapchain blit models (#2970)
+ - backends: report it better when not able to create texture?
+ - backends: glfw: could go idle when minimized? if (glfwGetWindowAttrib(window, GLFW_ICONIFIED)) { glfwWaitEvents(); continue; } // issue: DeltaTime will be super high on resume, perhaps provide a way to let impl know (#440)
+ - backends: opengl: rename imgui_impl_opengl2 to impl_opengl_legacy and imgui_impl_opengl3 to imgui_impl_opengl? (#1900)
+ - backends: opengl: could use a single vertex buffer and glBufferSubData for uploads?
+ - backends: opengl: explicitly disable GL_STENCIL_TEST in bindings.
+ - backends: vulkan: viewport: support for synchronized swapping of multiple swap chains.
+ - backends: bgfx: https://gist.github.com/RichardGale/6e2b74bc42b3005e08397236e4be0fd0
+ - backends: emscriptem: with refactored examples, we could provide a direct imgui_impl_emscripten platform layer (see eg. https://github.com/floooh/sokol-samples/blob/master/html5/imgui-emsc.cc#L42)
+
+ - bindings: ways to use clang ast dump to generate bindings or helpers for bindings? (e.g. clang++ -Xclang -ast-dump=json imgui.h) (WIP project "dear-bindings" still private)
+
+ - optimization: replace vsnprintf with stb_printf? using IMGUI_USE_STB_SPRINTF. (#1038 + needed for string_view)
+ - optimization: add clipping for multi-component widgets (SliderFloatX, ColorEditX, etc.). one problem is that nav branch can't easily clip parent group when there is a move request.
+ - optimization: add a flag to disable most of rendering, for the case where the user expect to skip it (#335)
+ - optimization: fully covered window (covered by another with non-translucent bg + WindowRounding worth of padding) may want to clip rendering.
+ - optimization: use another hash function than crc32, e.g. FNV1a
+ - optimization: turn some the various stack vectors into statically-sized arrays

ext/imgui/imconfig.h

@@ -0,0 +1,129 @@
+//-----------------------------------------------------------------------------
+// DEAR IMGUI COMPILE-TIME OPTIONS
+// Runtime options (clipboard callbacks, enabling various features, etc.) can generally be set via the ImGuiIO structure.
+// You can use ImGui::SetAllocatorFunctions() before calling ImGui::CreateContext() to rewire memory allocation functions.
+//-----------------------------------------------------------------------------
+// A) You may edit imconfig.h (and not overwrite it when updating Dear ImGui, or maintain a patch/rebased branch with your modifications to it)
+// B) or '#define IMGUI_USER_CONFIG "my_imgui_config.h"' in your project and then add directives in your own file without touching this template.
+//-----------------------------------------------------------------------------
+// You need to make sure that configuration settings are defined consistently _everywhere_ Dear ImGui is used, which include the imgui*.cpp
+// files but also _any_ of your code that uses Dear ImGui. This is because some compile-time options have an affect on data structures.
+// Defining those options in imconfig.h will ensure every compilation unit gets to see the same data structure layouts.
+// Call IMGUI_CHECKVERSION() from your .cpp file to verify that the data structures your files are using are matching the ones imgui.cpp is using.
+//-----------------------------------------------------------------------------
+
+#pragma once
+
+//---- Define assertion handler. Defaults to calling assert().
+// If your macro uses multiple statements, make sure is enclosed in a 'do { .. } while (0)' block so it can be used as a single statement.
+//#define IM_ASSERT(_EXPR)  MyAssert(_EXPR)
+//#define IM_ASSERT(_EXPR)  ((void)(_EXPR))     // Disable asserts
+
+//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows
+// Using Dear ImGui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
+// DLL users: heaps and globals are not shared across DLL boundaries! You will need to call SetCurrentContext() + SetAllocatorFunctions()
+// for each static/DLL boundary you are calling from. Read "Context and Memory Allocators" section of imgui.cpp for more details.
+//#define IMGUI_API __declspec( dllexport )
+//#define IMGUI_API __declspec( dllimport )
+
+//---- Don't define obsolete functions/enums/behaviors. Consider enabling from time to time after updating to clean your code of obsolete function/names.
+//#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+//#define IMGUI_DISABLE_OBSOLETE_KEYIO                      // 1.87: disable legacy io.KeyMap[]+io.KeysDown[] in favor io.AddKeyEvent(). This will be folded into IMGUI_DISABLE_OBSOLETE_FUNCTIONS in a few versions.
+
+//---- Disable all of Dear ImGui or don't implement standard windows/tools.
+// It is very strongly recommended to NOT disable the demo windows and debug tool during development. They are extremely useful in day to day work. Please read comments in imgui_demo.cpp.
+//#define IMGUI_DISABLE                                     // Disable everything: all headers and source files will be empty.
+//#define IMGUI_DISABLE_DEMO_WINDOWS                        // Disable demo windows: ShowDemoWindow()/ShowStyleEditor() will be empty.
+//#define IMGUI_DISABLE_DEBUG_TOOLS                         // Disable metrics/debugger and other debug tools: ShowMetricsWindow(), ShowDebugLogWindow() and ShowIDStackToolWindow() will be empty.
+
+//---- Don't implement some functions to reduce linkage requirements.
+//#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS   // [Win32] Don't implement default clipboard handler. Won't use and link with OpenClipboard/GetClipboardData/CloseClipboard etc. (user32.lib/.a, kernel32.lib/.a)
+//#define IMGUI_ENABLE_WIN32_DEFAULT_IME_FUNCTIONS          // [Win32] [Default with Visual Studio] Implement default IME handler (require imm32.lib/.a, auto-link for Visual Studio, -limm32 on command-line for MinGW)
+//#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] [Default with non-Visual Studio compilers] Don't implement default IME handler (won't require imm32.lib/.a)
+//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function (clipboard, IME).
+//#define IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS      // [OSX] Implement default OSX clipboard handler (need to link with '-framework ApplicationServices', this is why this is not the default).
+//#define IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS            // Don't implement ImFormatString/ImFormatStringV so you can implement them yourself (e.g. if you don't want to link with vsnprintf)
+//#define IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS              // Don't implement ImFabs/ImSqrt/ImPow/ImFmod/ImCos/ImSin/ImAcos/ImAtan2 so you can implement them yourself.
+//#define IMGUI_DISABLE_FILE_FUNCTIONS                      // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle at all (replace them with dummies)
+//#define IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS              // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle so you can implement them yourself if you don't want to link with fopen/fclose/fread/fwrite. This will also disable the LogToTTY() function.
+//#define IMGUI_DISABLE_DEFAULT_ALLOCATORS                  // Don't implement default allocators calling malloc()/free() to avoid linking with them. You will need to call ImGui::SetAllocatorFunctions().
+//#define IMGUI_DISABLE_SSE                                 // Disable use of SSE intrinsics even if available
+
+//---- Include imgui_user.h at the end of imgui.h as a convenience
+//#define IMGUI_INCLUDE_IMGUI_USER_H
+
+//---- Pack colors to BGRA8 instead of RGBA8 (to avoid converting from one to another)
+//#define IMGUI_USE_BGRA_PACKED_COLOR
+
+//---- Use 32-bit for ImWchar (default is 16-bit) to support unicode planes 1-16. (e.g. point beyond 0xFFFF like emoticons, dingbats, symbols, shapes, ancient languages, etc...)
+//#define IMGUI_USE_WCHAR32
+
+//---- Avoid multiple STB libraries implementations, or redefine path/filenames to prioritize another version
+// By default the embedded implementations are declared static and not available outside of Dear ImGui sources files.
+//#define IMGUI_STB_TRUETYPE_FILENAME   "my_folder/stb_truetype.h"
+//#define IMGUI_STB_RECT_PACK_FILENAME  "my_folder/stb_rect_pack.h"
+//#define IMGUI_STB_SPRINTF_FILENAME    "my_folder/stb_sprintf.h"    // only used if IMGUI_USE_STB_SPRINTF is defined.
+//#define IMGUI_DISABLE_STB_TRUETYPE_IMPLEMENTATION
+//#define IMGUI_DISABLE_STB_RECT_PACK_IMPLEMENTATION
+//#define IMGUI_DISABLE_STB_SPRINTF_IMPLEMENTATION                   // only disabled if IMGUI_USE_STB_SPRINTF is defined.
+
+//---- Use stb_sprintf.h for a faster implementation of vsnprintf instead of the one from libc (unless IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS is defined)
+// Compatibility checks of arguments and formats done by clang and GCC will be disabled in order to support the extra formats provided by stb_sprintf.h.
+//#define IMGUI_USE_STB_SPRINTF
+
+//---- Use FreeType to build and rasterize the font atlas (instead of stb_truetype which is embedded by default in Dear ImGui)
+// Requires FreeType headers to be available in the include path. Requires program to be compiled with 'misc/freetype/imgui_freetype.cpp' (in this repository) + the FreeType library (not provided).
+// On Windows you may use vcpkg with 'vcpkg install freetype --triplet=x64-windows' + 'vcpkg integrate install'.
+//#define IMGUI_ENABLE_FREETYPE
+
+//---- Use FreeType+lunasvg library to render OpenType SVG fonts (SVGinOT)
+// Requires lunasvg headers to be available in the include path + program to be linked with the lunasvg library (not provided).
+// Only works in combination with IMGUI_ENABLE_FREETYPE.
+// (implementation is based on Freetype's rsvg-port.c which is licensed under CeCILL-C Free Software License Agreement)
+//#define IMGUI_ENABLE_FREETYPE_LUNASVG
+
+//---- Use stb_truetype to build and rasterize the font atlas (default)
+// The only purpose of this define is if you want force compilation of the stb_truetype backend ALONG with the FreeType backend.
+//#define IMGUI_ENABLE_STB_TRUETYPE
+
+//---- Define constructor and implicit cast operators to convert back<>forth between your math types and ImVec2/ImVec4.
+// This will be inlined as part of ImVec2 and ImVec4 class declarations.
+/*
+#define IM_VEC2_CLASS_EXTRA                                                     \
+        constexpr ImVec2(const MyVec2& f) : x(f.x), y(f.y) {}                   \
+        operator MyVec2() const { return MyVec2(x,y); }
+
+#define IM_VEC4_CLASS_EXTRA                                                     \
+        constexpr ImVec4(const MyVec4& f) : x(f.x), y(f.y), z(f.z), w(f.w) {}   \
+        operator MyVec4() const { return MyVec4(x,y,z,w); }
+*/
+//---- ...Or use Dear ImGui's own very basic math operators.
+//#define IMGUI_DEFINE_MATH_OPERATORS
+
+//---- Use 32-bit vertex indices (default is 16-bit) is one way to allow large meshes with more than 64K vertices.
+// Your renderer backend will need to support it (most example renderer backends support both 16/32-bit indices).
+// Another way to allow large meshes while keeping 16-bit indices is to handle ImDrawCmd::VtxOffset in your renderer.
+// Read about ImGuiBackendFlags_RendererHasVtxOffset for details.
+//#define ImDrawIdx unsigned int
+
+//---- Override ImDrawCallback signature (will need to modify renderer backends accordingly)
+//struct ImDrawList;
+//struct ImDrawCmd;
+//typedef void (*MyImDrawCallback)(const ImDrawList* draw_list, const ImDrawCmd* cmd, void* my_renderer_user_data);
+//#define ImDrawCallback MyImDrawCallback
+
+//---- Debug Tools: Macro to break in Debugger (we provide a default implementation of this in the codebase)
+// (use 'Metrics->Tools->Item Picker' to pick widgets with the mouse and break into them for easy debugging.)
+//#define IM_DEBUG_BREAK  IM_ASSERT(0)
+//#define IM_DEBUG_BREAK  __debugbreak()
+
+//---- Debug Tools: Enable slower asserts
+//#define IMGUI_DEBUG_PARANOID
+
+//---- Tip: You can add extra functions within the ImGui:: namespace from anywhere (e.g. your own sources/header files)
+/*
+namespace ImGui
+{
+    void MyFunction(const char* name, MyMatrix44* mtx);
+}
+*/

ext/imgui/imstb_rectpack.h

@@ -0,0 +1,627 @@
+// [DEAR IMGUI]
+// This is a slightly modified version of stb_rect_pack.h 1.01.
+// Grep for [DEAR IMGUI] to find the changes.
+// 
+// stb_rect_pack.h - v1.01 - public domain - rectangle packing
+// Sean Barrett 2014
+//
+// Useful for e.g. packing rectangular textures into an atlas.
+// Does not do rotation.
+//
+// Before #including,
+//
+//    #define STB_RECT_PACK_IMPLEMENTATION
+//
+// in the file that you want to have the implementation.
+//
+// Not necessarily the awesomest packing method, but better than
+// the totally naive one in stb_truetype (which is primarily what
+// this is meant to replace).
+//
+// Has only had a few tests run, may have issues.
+//
+// More docs to come.
+//
+// No memory allocations; uses qsort() and assert() from stdlib.
+// Can override those by defining STBRP_SORT and STBRP_ASSERT.
+//
+// This library currently uses the Skyline Bottom-Left algorithm.
+//
+// Please note: better rectangle packers are welcome! Please
+// implement them to the same API, but with a different init
+// function.
+//
+// Credits
+//
+//  Library
+//    Sean Barrett
+//  Minor features
+//    Martins Mozeiko
+//    github:IntellectualKitty
+//
+//  Bugfixes / warning fixes
+//    Jeremy Jaussaud
+//    Fabian Giesen
+//
+// Version history:
+//
+//     1.01  (2021-07-11)  always use large rect mode, expose STBRP__MAXVAL in public section
+//     1.00  (2019-02-25)  avoid small space waste; gracefully fail too-wide rectangles
+//     0.99  (2019-02-07)  warning fixes
+//     0.11  (2017-03-03)  return packing success/fail result
+//     0.10  (2016-10-25)  remove cast-away-const to avoid warnings
+//     0.09  (2016-08-27)  fix compiler warnings
+//     0.08  (2015-09-13)  really fix bug with empty rects (w=0 or h=0)
+//     0.07  (2015-09-13)  fix bug with empty rects (w=0 or h=0)
+//     0.06  (2015-04-15)  added STBRP_SORT to allow replacing qsort
+//     0.05:  added STBRP_ASSERT to allow replacing assert
+//     0.04:  fixed minor bug in STBRP_LARGE_RECTS support
+//     0.01:  initial release
+//
+// LICENSE
+//
+//   See end of file for license information.
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//       INCLUDE SECTION
+//
+
+#ifndef STB_INCLUDE_STB_RECT_PACK_H
+#define STB_INCLUDE_STB_RECT_PACK_H
+
+#define STB_RECT_PACK_VERSION  1
+
+#ifdef STBRP_STATIC
+#define STBRP_DEF static
+#else
+#define STBRP_DEF extern
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct stbrp_context stbrp_context;
+typedef struct stbrp_node    stbrp_node;
+typedef struct stbrp_rect    stbrp_rect;
+
+typedef int            stbrp_coord;
+
+#define STBRP__MAXVAL  0x7fffffff
+// Mostly for internal use, but this is the maximum supported coordinate value.
+
+STBRP_DEF int stbrp_pack_rects (stbrp_context *context, stbrp_rect *rects, int num_rects);
+// Assign packed locations to rectangles. The rectangles are of type
+// 'stbrp_rect' defined below, stored in the array 'rects', and there
+// are 'num_rects' many of them.
+//
+// Rectangles which are successfully packed have the 'was_packed' flag
+// set to a non-zero value and 'x' and 'y' store the minimum location
+// on each axis (i.e. bottom-left in cartesian coordinates, top-left
+// if you imagine y increasing downwards). Rectangles which do not fit
+// have the 'was_packed' flag set to 0.
+//
+// You should not try to access the 'rects' array from another thread
+// while this function is running, as the function temporarily reorders
+// the array while it executes.
+//
+// To pack into another rectangle, you need to call stbrp_init_target
+// again. To continue packing into the same rectangle, you can call
+// this function again. Calling this multiple times with multiple rect
+// arrays will probably produce worse packing results than calling it
+// a single time with the full rectangle array, but the option is
+// available.
+//
+// The function returns 1 if all of the rectangles were successfully
+// packed and 0 otherwise.
+
+struct stbrp_rect
+{
+   // reserved for your use:
+   int            id;
+
+   // input:
+   stbrp_coord    w, h;
+
+   // output:
+   stbrp_coord    x, y;
+   int            was_packed;  // non-zero if valid packing
+
+}; // 16 bytes, nominally
+
+
+STBRP_DEF void stbrp_init_target (stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes);
+// Initialize a rectangle packer to:
+//    pack a rectangle that is 'width' by 'height' in dimensions
+//    using temporary storage provided by the array 'nodes', which is 'num_nodes' long
+//
+// You must call this function every time you start packing into a new target.
+//
+// There is no "shutdown" function. The 'nodes' memory must stay valid for
+// the following stbrp_pack_rects() call (or calls), but can be freed after
+// the call (or calls) finish.
+//
+// Note: to guarantee best results, either:
+//       1. make sure 'num_nodes' >= 'width'
+//   or  2. call stbrp_allow_out_of_mem() defined below with 'allow_out_of_mem = 1'
+//
+// If you don't do either of the above things, widths will be quantized to multiples
+// of small integers to guarantee the algorithm doesn't run out of temporary storage.
+//
+// If you do #2, then the non-quantized algorithm will be used, but the algorithm
+// may run out of temporary storage and be unable to pack some rectangles.
+
+STBRP_DEF void stbrp_setup_allow_out_of_mem (stbrp_context *context, int allow_out_of_mem);
+// Optionally call this function after init but before doing any packing to
+// change the handling of the out-of-temp-memory scenario, described above.
+// If you call init again, this will be reset to the default (false).
+
+
+STBRP_DEF void stbrp_setup_heuristic (stbrp_context *context, int heuristic);
+// Optionally select which packing heuristic the library should use. Different
+// heuristics will produce better/worse results for different data sets.
+// If you call init again, this will be reset to the default.
+
+enum
+{
+   STBRP_HEURISTIC_Skyline_default=0,
+   STBRP_HEURISTIC_Skyline_BL_sortHeight = STBRP_HEURISTIC_Skyline_default,
+   STBRP_HEURISTIC_Skyline_BF_sortHeight
+};
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// the details of the following structures don't matter to you, but they must
+// be visible so you can handle the memory allocations for them
+
+struct stbrp_node
+{
+   stbrp_coord  x,y;
+   stbrp_node  *next;
+};
+
+struct stbrp_context
+{
+   int width;
+   int height;
+   int align;
+   int init_mode;
+   int heuristic;
+   int num_nodes;
+   stbrp_node *active_head;
+   stbrp_node *free_head;
+   stbrp_node extra[2]; // we allocate two extra nodes so optimal user-node-count is 'width' not 'width+2'
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//     IMPLEMENTATION SECTION
+//
+
+#ifdef STB_RECT_PACK_IMPLEMENTATION
+#ifndef STBRP_SORT
+#include <stdlib.h>
+#define STBRP_SORT qsort
+#endif
+
+#ifndef STBRP_ASSERT
+#include <assert.h>
+#define STBRP_ASSERT assert
+#endif
+
+#ifdef _MSC_VER
+#define STBRP__NOTUSED(v)  (void)(v)
+#define STBRP__CDECL       __cdecl
+#else
+#define STBRP__NOTUSED(v)  (void)sizeof(v)
+#define STBRP__CDECL
+#endif
+
+enum
+{
+   STBRP__INIT_skyline = 1
+};
+
+STBRP_DEF void stbrp_setup_heuristic(stbrp_context *context, int heuristic)
+{
+   switch (context->init_mode) {
+      case STBRP__INIT_skyline:
+         STBRP_ASSERT(heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight || heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight);
+         context->heuristic = heuristic;
+         break;
+      default:
+         STBRP_ASSERT(0);
+   }
+}
+
+STBRP_DEF void stbrp_setup_allow_out_of_mem(stbrp_context *context, int allow_out_of_mem)
+{
+   if (allow_out_of_mem)
+      // if it's ok to run out of memory, then don't bother aligning them;
+      // this gives better packing, but may fail due to OOM (even though
+      // the rectangles easily fit). @TODO a smarter approach would be to only
+      // quantize once we've hit OOM, then we could get rid of this parameter.
+      context->align = 1;
+   else {
+      // if it's not ok to run out of memory, then quantize the widths
+      // so that num_nodes is always enough nodes.
+      //
+      // I.e. num_nodes * align >= width
+      //                  align >= width / num_nodes
+      //                  align = ceil(width/num_nodes)
+
+      context->align = (context->width + context->num_nodes-1) / context->num_nodes;
+   }
+}
+
+STBRP_DEF void stbrp_init_target(stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes)
+{
+   int i;
+
+   for (i=0; i < num_nodes-1; ++i)
+      nodes[i].next = &nodes[i+1];
+   nodes[i].next = NULL;
+   context->init_mode = STBRP__INIT_skyline;
+   context->heuristic = STBRP_HEURISTIC_Skyline_default;
+   context->free_head = &nodes[0];
+   context->active_head = &context->extra[0];
+   context->width = width;
+   context->height = height;
+   context->num_nodes = num_nodes;
+   stbrp_setup_allow_out_of_mem(context, 0);
+
+   // node 0 is the full width, node 1 is the sentinel (lets us not store width explicitly)
+   context->extra[0].x = 0;
+   context->extra[0].y = 0;
+   context->extra[0].next = &context->extra[1];
+   context->extra[1].x = (stbrp_coord) width;
+   context->extra[1].y = (1<<30);
+   context->extra[1].next = NULL;
+}
+
+// find minimum y position if it starts at x1
+static int stbrp__skyline_find_min_y(stbrp_context *c, stbrp_node *first, int x0, int width, int *pwaste)
+{
+   stbrp_node *node = first;
+   int x1 = x0 + width;
+   int min_y, visited_width, waste_area;
+
+   STBRP__NOTUSED(c);
+
+   STBRP_ASSERT(first->x <= x0);
+
+   #if 0
+   // skip in case we're past the node
+   while (node->next->x <= x0)
+      ++node;
+   #else
+   STBRP_ASSERT(node->next->x > x0); // we ended up handling this in the caller for efficiency
+   #endif
+
+   STBRP_ASSERT(node->x <= x0);
+
+   min_y = 0;
+   waste_area = 0;
+   visited_width = 0;
+   while (node->x < x1) {
+      if (node->y > min_y) {
+         // raise min_y higher.
+         // we've accounted for all waste up to min_y,
+         // but we'll now add more waste for everything we've visted
+         waste_area += visited_width * (node->y - min_y);
+         min_y = node->y;
+         // the first time through, visited_width might be reduced
+         if (node->x < x0)
+            visited_width += node->next->x - x0;
+         else
+            visited_width += node->next->x - node->x;
+      } else {
+         // add waste area
+         int under_width = node->next->x - node->x;
+         if (under_width + visited_width > width)
+            under_width = width - visited_width;
+         waste_area += under_width * (min_y - node->y);
+         visited_width += under_width;
+      }
+      node = node->next;
+   }
+
+   *pwaste = waste_area;
+   return min_y;
+}
+
+typedef struct
+{
+   int x,y;
+   stbrp_node **prev_link;
+} stbrp__findresult;
+
+static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int width, int height)
+{
+   int best_waste = (1<<30), best_x, best_y = (1 << 30);
+   stbrp__findresult fr;
+   stbrp_node **prev, *node, *tail, **best = NULL;
+
+   // align to multiple of c->align
+   width = (width + c->align - 1);
+   width -= width % c->align;
+   STBRP_ASSERT(width % c->align == 0);
+
+   // if it can't possibly fit, bail immediately
+   if (width > c->width || height > c->height) {
+      fr.prev_link = NULL;
+      fr.x = fr.y = 0;
+      return fr;
+   }
+
+   node = c->active_head;
+   prev = &c->active_head;
+   while (node->x + width <= c->width) {
+      int y,waste;
+      y = stbrp__skyline_find_min_y(c, node, node->x, width, &waste);
+      if (c->heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight) { // actually just want to test BL
+         // bottom left
+         if (y < best_y) {
+            best_y = y;
+            best = prev;
+         }
+      } else {
+         // best-fit
+         if (y + height <= c->height) {
+            // can only use it if it first vertically
+            if (y < best_y || (y == best_y && waste < best_waste)) {
+               best_y = y;
+               best_waste = waste;
+               best = prev;
+            }
+         }
+      }
+      prev = &node->next;
+      node = node->next;
+   }
+
+   best_x = (best == NULL) ? 0 : (*best)->x;
+
+   // if doing best-fit (BF), we also have to try aligning right edge to each node position
+   //
+   // e.g, if fitting
+   //
+   //     ____________________
+   //    |____________________|
+   //
+   //            into
+   //
+   //   |                         |
+   //   |             ____________|
+   //   |____________|
+   //
+   // then right-aligned reduces waste, but bottom-left BL is always chooses left-aligned
+   //
+   // This makes BF take about 2x the time
+
+   if (c->heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight) {
+      tail = c->active_head;
+      node = c->active_head;
+      prev = &c->active_head;
+      // find first node that's admissible
+      while (tail->x < width)
+         tail = tail->next;
+      while (tail) {
+         int xpos = tail->x - width;
+         int y,waste;
+         STBRP_ASSERT(xpos >= 0);
+         // find the left position that matches this
+         while (node->next->x <= xpos) {
+            prev = &node->next;
+            node = node->next;
+         }
+         STBRP_ASSERT(node->next->x > xpos && node->x <= xpos);
+         y = stbrp__skyline_find_min_y(c, node, xpos, width, &waste);
+         if (y + height <= c->height) {
+            if (y <= best_y) {
+               if (y < best_y || waste < best_waste || (waste==best_waste && xpos < best_x)) {
+                  best_x = xpos;
+                  //STBRP_ASSERT(y <= best_y); [DEAR IMGUI]
+                  best_y = y;
+                  best_waste = waste;
+                  best = prev;
+               }
+            }
+         }
+         tail = tail->next;
+      }
+   }
+
+   fr.prev_link = best;
+   fr.x = best_x;
+   fr.y = best_y;
+   return fr;
+}
+
+static stbrp__findresult stbrp__skyline_pack_rectangle(stbrp_context *context, int width, int height)
+{
+   // find best position according to heuristic
+   stbrp__findresult res = stbrp__skyline_find_best_pos(context, width, height);
+   stbrp_node *node, *cur;
+
+   // bail if:
+   //    1. it failed
+   //    2. the best node doesn't fit (we don't always check this)
+   //    3. we're out of memory
+   if (res.prev_link == NULL || res.y + height > context->height || context->free_head == NULL) {
+      res.prev_link = NULL;
+      return res;
+   }
+
+   // on success, create new node
+   node = context->free_head;
+   node->x = (stbrp_coord) res.x;
+   node->y = (stbrp_coord) (res.y + height);
+
+   context->free_head = node->next;
+
+   // insert the new node into the right starting point, and
+   // let 'cur' point to the remaining nodes needing to be
+   // stiched back in
+
+   cur = *res.prev_link;
+   if (cur->x < res.x) {
+      // preserve the existing one, so start testing with the next one
+      stbrp_node *next = cur->next;
+      cur->next = node;
+      cur = next;
+   } else {
+      *res.prev_link = node;
+   }
+
+   // from here, traverse cur and free the nodes, until we get to one
+   // that shouldn't be freed
+   while (cur->next && cur->next->x <= res.x + width) {
+      stbrp_node *next = cur->next;
+      // move the current node to the free list
+      cur->next = context->free_head;
+      context->free_head = cur;
+      cur = next;
+   }
+
+   // stitch the list back in
+   node->next = cur;
+
+   if (cur->x < res.x + width)
+      cur->x = (stbrp_coord) (res.x + width);
+
+#ifdef _DEBUG
+   cur = context->active_head;
+   while (cur->x < context->width) {
+      STBRP_ASSERT(cur->x < cur->next->x);
+      cur = cur->next;
+   }
+   STBRP_ASSERT(cur->next == NULL);
+
+   {
+      int count=0;
+      cur = context->active_head;
+      while (cur) {
+         cur = cur->next;
+         ++count;
+      }
+      cur = context->free_head;
+      while (cur) {
+         cur = cur->next;
+         ++count;
+      }
+      STBRP_ASSERT(count == context->num_nodes+2);
+   }
+#endif
+
+   return res;
+}
+
+static int STBRP__CDECL rect_height_compare(const void *a, const void *b)
+{
+   const stbrp_rect *p = (const stbrp_rect *) a;
+   const stbrp_rect *q = (const stbrp_rect *) b;
+   if (p->h > q->h)
+      return -1;
+   if (p->h < q->h)
+      return  1;
+   return (p->w > q->w) ? -1 : (p->w < q->w);
+}
+
+static int STBRP__CDECL rect_original_order(const void *a, const void *b)
+{
+   const stbrp_rect *p = (const stbrp_rect *) a;
+   const stbrp_rect *q = (const stbrp_rect *) b;
+   return (p->was_packed < q->was_packed) ? -1 : (p->was_packed > q->was_packed);
+}
+
+STBRP_DEF int stbrp_pack_rects(stbrp_context *context, stbrp_rect *rects, int num_rects)
+{
+   int i, all_rects_packed = 1;
+
+   // we use the 'was_packed' field internally to allow sorting/unsorting
+   for (i=0; i < num_rects; ++i) {
+      rects[i].was_packed = i;
+   }
+
+   // sort according to heuristic
+   STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_height_compare);
+
+   for (i=0; i < num_rects; ++i) {
+      if (rects[i].w == 0 || rects[i].h == 0) {
+         rects[i].x = rects[i].y = 0;  // empty rect needs no space
+      } else {
+         stbrp__findresult fr = stbrp__skyline_pack_rectangle(context, rects[i].w, rects[i].h);
+         if (fr.prev_link) {
+            rects[i].x = (stbrp_coord) fr.x;
+            rects[i].y = (stbrp_coord) fr.y;
+         } else {
+            rects[i].x = rects[i].y = STBRP__MAXVAL;
+         }
+      }
+   }
+
+   // unsort
+   STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_original_order);
+
+   // set was_packed flags and all_rects_packed status
+   for (i=0; i < num_rects; ++i) {
+      rects[i].was_packed = !(rects[i].x == STBRP__MAXVAL && rects[i].y == STBRP__MAXVAL);
+      if (!rects[i].was_packed)
+         all_rects_packed = 0;
+   }
+
+   // return the all_rects_packed status
+   return all_rects_packed;
+}
+#endif
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
+software, either in source code form or as a compiled binary, for any purpose,
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and to
+the detriment of our heirs and successors. We intend this dedication to be an
+overt act of relinquishment in perpetuity of all present and future rights to
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/

ext/imgui/misc/README.txt

@@ -0,0 +1,23 @@
+
+misc/cpp/
+  InputText() wrappers for C++ standard library (STL) type: std::string.
+  This is also an example of how you may wrap your own similar types.
+
+misc/debuggers/
+  Helper files for popular debuggers.
+  With the .natvis file, types like ImVector<> will be displayed nicely in Visual Studio debugger.
+
+misc/fonts/
+  Fonts loading/merging instructions (e.g. How to handle glyph ranges, how to merge icons fonts).
+  Command line tool "binary_to_compressed_c" to create compressed arrays to embed data in source code.
+  Suggested fonts and links.
+
+misc/freetype/
+  Font atlas builder/rasterizer using FreeType instead of stb_truetype.
+  Benefit from better FreeType rasterization, in particular for small fonts.
+
+misc/single_file/
+  Single-file header stub.
+  We use this to validate compiling all *.cpp files in a same compilation unit.
+  Users of that technique (also called "Unity builds") can generally provide this themselves,
+  so we don't really recommend you use this in your projects.

ext/imgui/misc/cpp/README.txt

@@ -0,0 +1,13 @@
+
+imgui_stdlib.h + imgui_stdlib.cpp
+  InputText() wrappers for C++ standard library (STL) type: std::string.
+  This is also an example of how you may wrap your own similar types.
+
+imgui_scoped.h
+  [Experimental, not currently in main repository]
+  Additional header file with some RAII-style wrappers for common Dear ImGui functions.
+  Try by merging: https://github.com/ocornut/imgui/pull/2197
+  Discuss at: https://github.com/ocornut/imgui/issues/2096
+
+See more C++ related extension (fmt, RAII, syntaxis sugar) on Wiki:
+  https://github.com/ocornut/imgui/wiki/Useful-Extensions#cness

ext/imgui/misc/cpp/imgui_stdlib.cpp

@@ -0,0 +1,85 @@
+// dear imgui: wrappers for C++ standard library (STL) types (std::string, etc.)
+// This is also an example of how you may wrap your own similar types.
+
+// Changelog:
+// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
+
+// See more C++ related extension (fmt, RAII, syntaxis sugar) on Wiki:
+//   https://github.com/ocornut/imgui/wiki/Useful-Extensions#cness
+
+#include "imgui.h"
+#include "imgui_stdlib.h"
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"    // warning: implicit conversion changes signedness
+#endif
+
+struct InputTextCallback_UserData
+{
+    std::string*            Str;
+    ImGuiInputTextCallback  ChainCallback;
+    void*                   ChainCallbackUserData;
+};
+
+static int InputTextCallback(ImGuiInputTextCallbackData* data)
+{
+    InputTextCallback_UserData* user_data = (InputTextCallback_UserData*)data->UserData;
+    if (data->EventFlag == ImGuiInputTextFlags_CallbackResize)
+    {
+        // Resize string callback
+        // If for some reason we refuse the new length (BufTextLen) and/or capacity (BufSize) we need to set them back to what we want.
+        std::string* str = user_data->Str;
+        IM_ASSERT(data->Buf == str->c_str());
+        str->resize(data->BufTextLen);
+        data->Buf = (char*)str->c_str();
+    }
+    else if (user_data->ChainCallback)
+    {
+        // Forward to user callback, if any
+        data->UserData = user_data->ChainCallbackUserData;
+        return user_data->ChainCallback(data);
+    }
+    return 0;
+}
+
+bool ImGui::InputText(const char* label, std::string* str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputText(label, (char*)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
+}
+
+bool ImGui::InputTextMultiline(const char* label, std::string* str, const ImVec2& size, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputTextMultiline(label, (char*)str->c_str(), str->capacity() + 1, size, flags, InputTextCallback, &cb_user_data);
+}
+
+bool ImGui::InputTextWithHint(const char* label, const char* hint, std::string* str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputTextWithHint(label, hint, (char*)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
+}
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif

ext/imgui/misc/cpp/imgui_stdlib.h

@@ -0,0 +1,21 @@
+// dear imgui: wrappers for C++ standard library (STL) types (std::string, etc.)
+// This is also an example of how you may wrap your own similar types.
+
+// Changelog:
+// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
+
+// See more C++ related extension (fmt, RAII, syntaxis sugar) on Wiki:
+//   https://github.com/ocornut/imgui/wiki/Useful-Extensions#cness
+
+#pragma once
+
+#include <string>
+
+namespace ImGui
+{
+    // ImGui::InputText() with std::string
+    // Because text input needs dynamic resizing, we need to setup a callback to grow the capacity
+    IMGUI_API bool  InputText(const char* label, std::string* str, ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = nullptr, void* user_data = nullptr);
+    IMGUI_API bool  InputTextMultiline(const char* label, std::string* str, const ImVec2& size = ImVec2(0, 0), ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = nullptr, void* user_data = nullptr);
+    IMGUI_API bool  InputTextWithHint(const char* label, const char* hint, std::string* str, ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = nullptr, void* user_data = nullptr);
+}

ext/imgui/misc/debuggers/README.txt

@@ -0,0 +1,16 @@
+
+HELPER FILES FOR POPULAR DEBUGGERS
+
+imgui.gdb
+    GDB: disable stepping into trivial functions.
+    (read comments inside file for details)
+
+imgui.natstepfilter
+    Visual Studio Debugger: disable stepping into trivial functions.
+    (read comments inside file for details)
+
+imgui.natvis
+    Visual Studio Debugger: describe Dear ImGui types for better display.
+    With this, types like ImVector<> will be displayed nicely in the debugger.
+    (read comments inside file for details)
+

ext/imgui/misc/debuggers/imgui.gdb

@@ -0,0 +1,12 @@
+# GDB configuration to aid debugging experience
+
+# To enable these customizations edit $HOME/.gdbinit (or ./.gdbinit if local gdbinit is enabled) and add:
+#   add-auto-load-safe-path /path/to/imgui.gdb
+#   source /path/to/imgui.gdb
+#
+# More Information at:
+#   * https://sourceware.org/gdb/current/onlinedocs/gdb/gdbinit-man.html
+#   * https://sourceware.org/gdb/current/onlinedocs/gdb/Init-File-in-the-Current-Directory.html#Init-File-in-the-Current-Directory
+
+# Disable stepping into trivial functions
+skip -rfunction Im(Vec2|Vec4|Strv|Vector|Span)::.+

ext/imgui/misc/debuggers/imgui.natstepfilter

@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+.natstepfilter file for Visual Studio debugger.
+Purpose: instruct debugger to skip some functions when using StepInto (F11)
+
+Since Visual Studio 2022 version 17.6 Preview 2 (currently available as a "Preview" build on March 14, 2023)
+It is possible to add the .natstepfilter file to your project file and it will automatically be used.
+(https://developercommunity.visualstudio.com/t/allow-natstepfilter-and-natjmc-to-be-included-as-p/561718)
+
+For older Visual Studio version prior to 2022 17.6 Preview 2:
+* copy in %USERPROFILE%\Documents\Visual Studio XXXX\Visualizers (current user)
+* or copy in %VsInstallDirectory%\Common7\Packages\Debugger\Visualizers (all users)
+If you have multiple VS version installed, the version that matters is the one you are using the IDE/debugger
+of (not the compiling toolset). This is supported since Visual Studio 2012.
+
+More information at: https://docs.microsoft.com/en-us/visualstudio/debugger/just-my-code?view=vs-2019#BKMK_C___Just_My_Code
+-->
+
+<StepFilter xmlns="http://schemas.microsoft.com/vstudio/debugger/natstepfilter/2010">
+
+    <!-- Disable stepping into trivial functions -->
+    <Function>
+        <Name>(ImVec2|ImVec4|ImStrv)::.+</Name>
+        <Action>NoStepInto</Action>
+    </Function>
+    <Function>
+        <Name>(ImVector|ImSpan).*::operator.+</Name>
+        <Action>NoStepInto</Action>
+    </Function>
+
+</StepFilter>

ext/imgui/misc/debuggers/imgui.natvis

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+.natvis file for Visual Studio debugger.
+Purpose: provide nicer views on data types used by Dear ImGui.
+
+To enable:
+* include file in your VS project (most recommended: not intrusive and always kept up to date!)
+* or copy in %USERPROFILE%\Documents\Visual Studio XXXX\Visualizers (current user)
+* or copy in %VsInstallDirectory%\Common7\Packages\Debugger\Visualizers (all users)
+
+More information at: https://docs.microsoft.com/en-us/visualstudio/debugger/create-custom-views-of-native-objects?view=vs-2019
+-->
+
+<AutoVisualizer xmlns="http://schemas.microsoft.com/vstudio/debugger/natvis/2010">
+
+<Type Name="ImVector&lt;*&gt;">
+  <DisplayString>{{Size={Size} Capacity={Capacity}}}</DisplayString>
+  <Expand>
+    <ArrayItems>
+      <Size>Size</Size>
+      <ValuePointer>Data</ValuePointer>
+    </ArrayItems>
+  </Expand>
+</Type>
+
+<Type Name="ImSpan&lt;*&gt;">
+  <DisplayString>{{Size={DataEnd-Data} }}</DisplayString>
+  <Expand>
+    <ArrayItems>
+      <Size>DataEnd-Data</Size>
+      <ValuePointer>Data</ValuePointer>
+    </ArrayItems>
+  </Expand>
+</Type>
+
+<Type Name="ImVec2">
+  <DisplayString>{{x={x,g} y={y,g}}}</DisplayString>
+</Type>
+
+<Type Name="ImVec4">
+  <DisplayString>{{x={x,g} y={y,g} z={z,g} w={w,g}}}</DisplayString>
+</Type>
+
+<Type Name="ImRect">
+  <DisplayString>{{Min=({Min.x,g} {Min.y,g}) Max=({Max.x,g} {Max.y,g}) Size=({Max.x-Min.x,g} {Max.y-Min.y,g})}}</DisplayString>
+  <Expand>
+    <Item Name="Min">Min</Item>
+    <Item Name="Max">Max</Item>
+    <Item Name="[Width]">Max.x - Min.x</Item>
+    <Item Name="[Height]">Max.y - Min.y</Item>
+  </Expand>
+</Type>
+
+<Type Name="ImGuiWindow">
+  <DisplayString>{{Name {Name,s} Active {(Active||WasActive)?1:0,d} Child {(Flags &amp; 0x01000000)?1:0,d} Popup {(Flags &amp; 0x04000000)?1:0,d} Hidden {(Hidden)?1:0,d}}</DisplayString>
+</Type>
+
+</AutoVisualizer>

ext/imgui/misc/fonts/binary_to_compressed_c.cpp

@@ -0,0 +1,388 @@
+// dear imgui
+// (binary_to_compressed_c.cpp)
+// Helper tool to turn a file into a C array, if you want to embed font data in your source code.
+
+// The data is first compressed with stb_compress() to reduce source code size,
+// then encoded in Base85 to fit in a string so we can fit roughly 4 bytes of compressed data into 5 bytes of source code (suggested by @mmalex)
+// (If we used 32-bit constants it would require take 11 bytes of source code to encode 4 bytes, and be endianness dependent)
+// Note that even with compression, the output array is likely to be bigger than the binary file..
+// Load compressed TTF fonts with ImGui::GetIO().Fonts->AddFontFromMemoryCompressedTTF()
+
+// Build with, e.g:
+//   # cl.exe binary_to_compressed_c.cpp
+//   # g++ binary_to_compressed_c.cpp
+//   # clang++ binary_to_compressed_c.cpp
+// You can also find a precompiled Windows binary in the binary/demo package available from https://github.com/ocornut/imgui
+
+// Usage:
+//   binary_to_compressed_c.exe [-base85] [-nocompress] [-nostatic] <inputfile> <symbolname>
+// Usage example:
+//   # binary_to_compressed_c.exe myfont.ttf MyFont > myfont.cpp
+//   # binary_to_compressed_c.exe -base85 myfont.ttf MyFont > myfont.cpp
+
+#define _CRT_SECURE_NO_WARNINGS
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+
+// stb_compress* from stb.h - declaration
+typedef unsigned int stb_uint;
+typedef unsigned char stb_uchar;
+stb_uint stb_compress(stb_uchar* out, stb_uchar* in, stb_uint len);
+
+static bool binary_to_compressed_c(const char* filename, const char* symbol, bool use_base85_encoding, bool use_compression, bool use_static);
+
+int main(int argc, char** argv)
+{
+    if (argc < 3)
+    {
+        printf("Syntax: %s [-base85] [-nocompress] [-nostatic] <inputfile> <symbolname>\n", argv[0]);
+        return 0;
+    }
+
+    int argn = 1;
+    bool use_base85_encoding = false;
+    bool use_compression = true;
+    bool use_static = true;
+    while (argn < (argc - 2) && argv[argn][0] == '-')
+    {
+        if (strcmp(argv[argn], "-base85") == 0) { use_base85_encoding = true; argn++; }
+        else if (strcmp(argv[argn], "-nocompress") == 0) { use_compression = false; argn++; }
+        else if (strcmp(argv[argn], "-nostatic") == 0) { use_static = false; argn++; }
+        else
+        {
+            fprintf(stderr, "Unknown argument: '%s'\n", argv[argn]);
+            return 1;
+        }
+    }
+
+    bool ret = binary_to_compressed_c(argv[argn], argv[argn + 1], use_base85_encoding, use_compression, use_static);
+    if (!ret)
+        fprintf(stderr, "Error opening or reading file: '%s'\n", argv[argn]);
+    return ret ? 0 : 1;
+}
+
+char Encode85Byte(unsigned int x)
+{
+    x = (x % 85) + 35;
+    return (char)((x >= '\\') ? x + 1 : x);
+}
+
+bool binary_to_compressed_c(const char* filename, const char* symbol, bool use_base85_encoding, bool use_compression, bool use_static)
+{
+    // Read file
+    FILE* f = fopen(filename, "rb");
+    if (!f) return false;
+    int data_sz;
+    if (fseek(f, 0, SEEK_END) || (data_sz = (int)ftell(f)) == -1 || fseek(f, 0, SEEK_SET)) { fclose(f); return false; }
+    char* data = new char[data_sz + 4];
+    if (fread(data, 1, data_sz, f) != (size_t)data_sz) { fclose(f); delete[] data; return false; }
+    memset((void*)(((char*)data) + data_sz), 0, 4);
+    fclose(f);
+
+    // Compress
+    int maxlen = data_sz + 512 + (data_sz >> 2) + sizeof(int); // total guess
+    char* compressed = use_compression ? new char[maxlen] : data;
+    int compressed_sz = use_compression ? stb_compress((stb_uchar*)compressed, (stb_uchar*)data, data_sz) : data_sz;
+    if (use_compression)
+        memset(compressed + compressed_sz, 0, maxlen - compressed_sz);
+
+    // Output as Base85 encoded
+    FILE* out = stdout;
+    fprintf(out, "// File: '%s' (%d bytes)\n", filename, (int)data_sz);
+    fprintf(out, "// Exported using binary_to_compressed_c.cpp\n");
+    const char* static_str = use_static ? "static " : "";
+    const char* compressed_str = use_compression ? "compressed_" : "";
+    if (use_base85_encoding)
+    {
+        fprintf(out, "%sconst char %s_%sdata_base85[%d+1] =\n    \"", static_str, symbol, compressed_str, (int)((compressed_sz + 3) / 4)*5);
+        char prev_c = 0;
+        for (int src_i = 0; src_i < compressed_sz; src_i += 4)
+        {
+            // This is made a little more complicated by the fact that ??X sequences are interpreted as trigraphs by old C/C++ compilers. So we need to escape pairs of ??.
+            unsigned int d = *(unsigned int*)(compressed + src_i);
+            for (unsigned int n5 = 0; n5 < 5; n5++, d /= 85)
+            {
+                char c = Encode85Byte(d);
+                fprintf(out, (c == '?' && prev_c == '?') ? "\\%c" : "%c", c);
+                prev_c = c;
+            }
+            if ((src_i % 112) == 112 - 4)
+                fprintf(out, "\"\n    \"");
+        }
+        fprintf(out, "\";\n\n");
+    }
+    else
+    {
+        fprintf(out, "%sconst unsigned int %s_%ssize = %d;\n", static_str, symbol, compressed_str, (int)compressed_sz);
+        fprintf(out, "%sconst unsigned int %s_%sdata[%d/4] =\n{", static_str, symbol, compressed_str, (int)((compressed_sz + 3) / 4)*4);
+        int column = 0;
+        for (int i = 0; i < compressed_sz; i += 4)
+        {
+            unsigned int d = *(unsigned int*)(compressed + i);
+            if ((column++ % 12) == 0)
+                fprintf(out, "\n    0x%08x, ", d);
+            else
+                fprintf(out, "0x%08x, ", d);
+        }
+        fprintf(out, "\n};\n\n");
+    }
+
+    // Cleanup
+    delete[] data;
+    if (use_compression)
+        delete[] compressed;
+    return true;
+}
+
+// stb_compress* from stb.h - definition
+
+////////////////////           compressor         ///////////////////////
+
+static stb_uint stb_adler32(stb_uint adler32, stb_uchar *buffer, stb_uint buflen)
+{
+    const unsigned long ADLER_MOD = 65521;
+    unsigned long s1 = adler32 & 0xffff, s2 = adler32 >> 16;
+    unsigned long blocklen, i;
+
+    blocklen = buflen % 5552;
+    while (buflen) {
+        for (i=0; i + 7 < blocklen; i += 8) {
+            s1 += buffer[0], s2 += s1;
+            s1 += buffer[1], s2 += s1;
+            s1 += buffer[2], s2 += s1;
+            s1 += buffer[3], s2 += s1;
+            s1 += buffer[4], s2 += s1;
+            s1 += buffer[5], s2 += s1;
+            s1 += buffer[6], s2 += s1;
+            s1 += buffer[7], s2 += s1;
+
+            buffer += 8;
+        }
+
+        for (; i < blocklen; ++i)
+            s1 += *buffer++, s2 += s1;
+
+        s1 %= ADLER_MOD, s2 %= ADLER_MOD;
+        buflen -= blocklen;
+        blocklen = 5552;
+    }
+    return (s2 << 16) + s1;
+}
+
+static unsigned int stb_matchlen(stb_uchar *m1, stb_uchar *m2, stb_uint maxlen)
+{
+    stb_uint i;
+    for (i=0; i < maxlen; ++i)
+        if (m1[i] != m2[i]) return i;
+    return i;
+}
+
+// simple implementation that just takes the source data in a big block
+
+static stb_uchar *stb__out;
+static FILE      *stb__outfile;
+static stb_uint   stb__outbytes;
+
+static void stb__write(unsigned char v)
+{
+    fputc(v, stb__outfile);
+    ++stb__outbytes;
+}
+
+//#define stb_out(v)    (stb__out ? *stb__out++ = (stb_uchar) (v) : stb__write((stb_uchar) (v)))
+#define stb_out(v)    do { if (stb__out) *stb__out++ = (stb_uchar) (v); else stb__write((stb_uchar) (v)); } while (0)
+
+static void stb_out2(stb_uint v) { stb_out(v >> 8); stb_out(v); }
+static void stb_out3(stb_uint v) { stb_out(v >> 16); stb_out(v >> 8); stb_out(v); }
+static void stb_out4(stb_uint v) { stb_out(v >> 24); stb_out(v >> 16); stb_out(v >> 8 ); stb_out(v); }
+
+static void outliterals(stb_uchar *in, int numlit)
+{
+    while (numlit > 65536) {
+        outliterals(in,65536);
+        in     += 65536;
+        numlit -= 65536;
+    }
+
+    if      (numlit ==     0)    ;
+    else if (numlit <=    32)    stb_out (0x000020 + numlit-1);
+    else if (numlit <=  2048)    stb_out2(0x000800 + numlit-1);
+    else /*  numlit <= 65536) */ stb_out3(0x070000 + numlit-1);
+
+    if (stb__out) {
+        memcpy(stb__out,in,numlit);
+        stb__out += numlit;
+    } else
+        fwrite(in, 1, numlit, stb__outfile);
+}
+
+static int stb__window = 0x40000; // 256K
+
+static int stb_not_crap(int best, int dist)
+{
+    return   ((best > 2  &&  dist <= 0x00100)
+        || (best > 5  &&  dist <= 0x04000)
+        || (best > 7  &&  dist <= 0x80000));
+}
+
+static  stb_uint stb__hashsize = 32768;
+
+// note that you can play with the hashing functions all you
+// want without needing to change the decompressor
+#define stb__hc(q,h,c)      (((h) << 7) + ((h) >> 25) + q[c])
+#define stb__hc2(q,h,c,d)   (((h) << 14) + ((h) >> 18) + (q[c] << 7) + q[d])
+#define stb__hc3(q,c,d,e)   ((q[c] << 14) + (q[d] << 7) + q[e])
+
+static unsigned int stb__running_adler;
+
+static int stb_compress_chunk(stb_uchar *history,
+    stb_uchar *start,
+    stb_uchar *end,
+    int length,
+    int *pending_literals,
+    stb_uchar **chash,
+    stb_uint mask)
+{
+    (void)history;
+    int window = stb__window;
+    stb_uint match_max;
+    stb_uchar *lit_start = start - *pending_literals;
+    stb_uchar *q = start;
+
+#define STB__SCRAMBLE(h)   (((h) + ((h) >> 16)) & mask)
+
+    // stop short of the end so we don't scan off the end doing
+    // the hashing; this means we won't compress the last few bytes
+    // unless they were part of something longer
+    while (q < start+length && q+12 < end) {
+        int m;
+        stb_uint h1,h2,h3,h4, h;
+        stb_uchar *t;
+        int best = 2, dist=0;
+
+        if (q+65536 > end)
+            match_max = (stb_uint)(end-q);
+        else
+            match_max = 65536;
+
+#define stb__nc(b,d)  ((d) <= window && ((b) > 9 || stb_not_crap((int)(b),(int)(d))))
+
+#define STB__TRY(t,p)  /* avoid retrying a match we already tried */ \
+    if (p ? dist != (int)(q-t) : 1)                             \
+    if ((m = stb_matchlen(t, q, match_max)) > best)     \
+    if (stb__nc(m,q-(t)))                                \
+    best = m, dist = (int)(q - (t))
+
+        // rather than search for all matches, only try 4 candidate locations,
+        // chosen based on 4 different hash functions of different lengths.
+        // this strategy is inspired by LZO; hashing is unrolled here using the
+        // 'hc' macro
+        h = stb__hc3(q,0, 1, 2); h1 = STB__SCRAMBLE(h);
+        t = chash[h1]; if (t) STB__TRY(t,0);
+        h = stb__hc2(q,h, 3, 4); h2 = STB__SCRAMBLE(h);
+        h = stb__hc2(q,h, 5, 6);        t = chash[h2]; if (t) STB__TRY(t,1);
+        h = stb__hc2(q,h, 7, 8); h3 = STB__SCRAMBLE(h);
+        h = stb__hc2(q,h, 9,10);        t = chash[h3]; if (t) STB__TRY(t,1);
+        h = stb__hc2(q,h,11,12); h4 = STB__SCRAMBLE(h);
+        t = chash[h4]; if (t) STB__TRY(t,1);
+
+        // because we use a shared hash table, can only update it
+        // _after_ we've probed all of them
+        chash[h1] = chash[h2] = chash[h3] = chash[h4] = q;
+
+        if (best > 2)
+            assert(dist > 0);
+
+        // see if our best match qualifies
+        if (best < 3) { // fast path literals
+            ++q;
+        } else if (best > 2  &&  best <= 0x80    &&  dist <= 0x100) {
+            outliterals(lit_start, (int)(q-lit_start)); lit_start = (q += best);
+            stb_out(0x80 + best-1);
+            stb_out(dist-1);
+        } else if (best > 5  &&  best <= 0x100   &&  dist <= 0x4000) {
+            outliterals(lit_start, (int)(q-lit_start)); lit_start = (q += best);
+            stb_out2(0x4000 + dist-1);
+            stb_out(best-1);
+        } else if (best > 7  &&  best <= 0x100   &&  dist <= 0x80000) {
+            outliterals(lit_start, (int)(q-lit_start)); lit_start = (q += best);
+            stb_out3(0x180000 + dist-1);
+            stb_out(best-1);
+        } else if (best > 8  &&  best <= 0x10000 &&  dist <= 0x80000) {
+            outliterals(lit_start, (int)(q-lit_start)); lit_start = (q += best);
+            stb_out3(0x100000 + dist-1);
+            stb_out2(best-1);
+        } else if (best > 9                      &&  dist <= 0x1000000) {
+            if (best > 65536) best = 65536;
+            outliterals(lit_start, (int)(q-lit_start)); lit_start = (q += best);
+            if (best <= 0x100) {
+                stb_out(0x06);
+                stb_out3(dist-1);
+                stb_out(best-1);
+            } else {
+                stb_out(0x04);
+                stb_out3(dist-1);
+                stb_out2(best-1);
+            }
+        } else {  // fallback literals if no match was a balanced tradeoff
+            ++q;
+        }
+    }
+
+    // if we didn't get all the way, add the rest to literals
+    if (q-start < length)
+        q = start+length;
+
+    // the literals are everything from lit_start to q
+    *pending_literals = (int)(q - lit_start);
+
+    stb__running_adler = stb_adler32(stb__running_adler, start, (stb_uint)(q - start));
+    return (int)(q - start);
+}
+
+static int stb_compress_inner(stb_uchar *input, stb_uint length)
+{
+    int literals = 0;
+    stb_uint len,i;
+
+    stb_uchar **chash;
+    chash = (stb_uchar**) malloc(stb__hashsize * sizeof(stb_uchar*));
+    if (chash == nullptr) return 0; // failure
+    for (i=0; i < stb__hashsize; ++i)
+        chash[i] = nullptr;
+
+    // stream signature
+    stb_out(0x57); stb_out(0xbc);
+    stb_out2(0);
+
+    stb_out4(0);       // 64-bit length requires 32-bit leading 0
+    stb_out4(length);
+    stb_out4(stb__window);
+
+    stb__running_adler = 1;
+
+    len = stb_compress_chunk(input, input, input+length, length, &literals, chash, stb__hashsize-1);
+    assert(len == length);
+
+    outliterals(input+length - literals, literals);
+
+    free(chash);
+
+    stb_out2(0x05fa); // end opcode
+
+    stb_out4(stb__running_adler);
+
+    return 1; // success
+}
+
+stb_uint stb_compress(stb_uchar *out, stb_uchar *input, stb_uint length)
+{
+    stb__out = out;
+    stb__outfile = nullptr;
+
+    stb_compress_inner(input, length);
+
+    return (stb_uint)(stb__out - out);
+}

ext/imgui/misc/freetype/README.md

@@ -0,0 +1,44 @@
+# imgui_freetype
+
+Build font atlases using FreeType instead of stb_truetype (which is the default font rasterizer).
+<br>by @vuhdo, @mikesart, @ocornut.
+
+### Usage
+
+1. Get latest FreeType binaries or build yourself (under Windows you may use vcpkg with `vcpkg install freetype --triplet=x64-windows`, `vcpkg integrate install`).
+2. Add imgui_freetype.h/cpp alongside your project files.
+3. Add `#define IMGUI_ENABLE_FREETYPE` in your [imconfig.h](https://github.com/ocornut/imgui/blob/master/imconfig.h) file
+
+### About Gamma Correct Blending
+
+FreeType assumes blending in linear space rather than gamma space.
+See FreeType note for [FT_Render_Glyph](https://freetype.org/freetype2/docs/reference/ft2-glyph_retrieval.html#ft_render_glyph).
+For correct results you need to be using sRGB and convert to linear space in the pixel shader output.
+The default Dear ImGui styles will be impacted by this change (alpha values will need tweaking).
+
+### Testbed for toying with settings (for developers)
+
+See https://gist.github.com/ocornut/b3a9ecf13502fd818799a452969649ad
+
+### Known issues
+
+- Oversampling settings are ignored but also not so much necessary with the higher quality rendering.
+
+### Comparison
+
+Small, thin anti-aliased fonts typically benefit a lot from FreeType's hinting:
+![comparing_font_rasterizers](https://user-images.githubusercontent.com/8225057/107550178-fef87f00-6bd0-11eb-8d09-e2edb2f0ccfc.gif)
+
+### Colorful glyphs/emojis
+
+You can use the `ImGuiFreeTypeBuilderFlags_LoadColor` flag to load certain colorful glyphs. See the
+["Using Colorful Glyphs/Emojis"](https://github.com/ocornut/imgui/blob/master/docs/FONTS.md#using-colorful-glyphsemojis) section of FONTS.md.
+
+![colored glyphs](https://user-images.githubusercontent.com/8225057/106171241-9dc4ba80-6191-11eb-8a69-ca1467b206d1.png)
+
+### Using OpenType SVG fonts (SVGinOT)
+- *SVG in Open Type* is a standard by Adobe and Mozilla for color OpenType and Open Font Format fonts. It allows font creators to embed complete SVG files within a font enabling full color and even animations.
+- Popular fonts such as [twemoji](https://github.com/13rac1/twemoji-color-font) and fonts made with [scfbuild](https://github.com/13rac1/scfbuild) is SVGinOT
+- Requires: [lunasvg](https://github.com/sammycage/lunasvg) v2.3.2 and above
+    1. Add `#define IMGUI_ENABLE_FREETYPE_LUNASVG` in your `imconfig.h`.
+    2. Get latest lunasvg binaries or build yourself. Under Windows you may use vcpkg with: `vcpkg install lunasvg --triplet=x64-windows`.

ext/imgui/misc/freetype/imgui_freetype.cpp

@@ -0,0 +1,944 @@
+// dear imgui: FreeType font builder (used as a replacement for the stb_truetype builder)
+// (code)
+
+// Get the latest version at https://github.com/ocornut/imgui/tree/master/misc/freetype
+// Original code by @vuhdo (Aleksei Skriabin). Improvements by @mikesart. Maintained since 2019 by @ocornut.
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023/08/01: added support for SVG fonts, enable by using '#define IMGUI_ENABLE_FREETYPE_LUNASVG' (#6591)
+//  2023/01/04: fixed a packing issue which in some occurrences would prevent large amount of glyphs from being packed correctly.
+//  2021/08/23: fixed crash when FT_Render_Glyph() fails to render a glyph and returns NULL.
+//  2021/03/05: added ImGuiFreeTypeBuilderFlags_Bitmap to load bitmap glyphs.
+//  2021/03/02: set 'atlas->TexPixelsUseColors = true' to help some backends with deciding of a prefered texture format.
+//  2021/01/28: added support for color-layered glyphs via ImGuiFreeTypeBuilderFlags_LoadColor (require Freetype 2.10+).
+//  2021/01/26: simplified integration by using '#define IMGUI_ENABLE_FREETYPE'. renamed ImGuiFreeType::XXX flags to ImGuiFreeTypeBuilderFlags_XXX for consistency with other API. removed ImGuiFreeType::BuildFontAtlas().
+//  2020/06/04: fix for rare case where FT_Get_Char_Index() succeed but FT_Load_Glyph() fails.
+//  2019/02/09: added RasterizerFlags::Monochrome flag to disable font anti-aliasing (combine with ::MonoHinting for best results!)
+//  2019/01/15: added support for imgui allocators + added FreeType only override function SetAllocatorFunctions().
+//  2019/01/10: re-factored to match big update in STB builder. fixed texture height waste. fixed redundant glyphs when merging. support for glyph padding.
+//  2018/06/08: added support for ImFontConfig::GlyphMinAdvanceX, GlyphMaxAdvanceX.
+//  2018/02/04: moved to main imgui repository (away from http://www.github.com/ocornut/imgui_club)
+//  2018/01/22: fix for addition of ImFontAtlas::TexUvscale member.
+//  2017/10/22: minor inconsequential change to match change in master (removed an unnecessary statement).
+//  2017/09/26: fixes for imgui internal changes.
+//  2017/08/26: cleanup, optimizations, support for ImFontConfig::RasterizerFlags, ImFontConfig::RasterizerMultiply.
+//  2017/08/16: imported from https://github.com/Vuhdo/imgui_freetype into http://www.github.com/ocornut/imgui_club, updated for latest changes in ImFontAtlas, minor tweaks.
+
+// About Gamma Correct Blending:
+// - FreeType assumes blending in linear space rather than gamma space.
+// - See https://www.freetype.org/freetype2/docs/reference/ft2-base_interface.html#FT_Render_Glyph
+// - For correct results you need to be using sRGB and convert to linear space in the pixel shader output.
+// - The default dear imgui styles will be impacted by this change (alpha values will need tweaking).
+
+// FIXME: cfg.OversampleH, OversampleV are not supported (but perhaps not so necessary with this rasterizer).
+
+#include "imgui.h"
+#ifndef IMGUI_DISABLE
+#include "imgui_freetype.h"
+#include "imgui_internal.h"     // ImMin,ImMax,ImFontAtlasBuild*,
+#include <stdint.h>
+#include <ft2build.h>
+#include FT_FREETYPE_H          // <freetype/freetype.h>
+#include FT_MODULE_H            // <freetype/ftmodapi.h>
+#include FT_GLYPH_H             // <freetype/ftglyph.h>
+#include FT_SYNTHESIS_H         // <freetype/ftsynth.h>
+
+#ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+#include FT_OTSVG_H             // <freetype/otsvg.h>
+#include FT_BBOX_H              // <freetype/ftbbox.h>
+#include <lunasvg.h>
+#if !((FREETYPE_MAJOR >= 2) && (FREETYPE_MINOR >= 12))
+#error IMGUI_ENABLE_FREETYPE_LUNASVG requires FreeType version >= 2.12
+#endif
+#endif
+
+#ifdef _MSC_VER
+#pragma warning (push)
+#pragma warning (disable: 4505)     // unreferenced local function has been removed (stb stuff)
+#pragma warning (disable: 26812)    // [Static Analyzer] The enum type 'xxx' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).
+#endif
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpragmas"                  // warning: unknown option after '#pragma GCC diagnostic' kind
+#pragma GCC diagnostic ignored "-Wunused-function"          // warning: 'xxxx' defined but not used
+#ifndef __clang__
+#pragma GCC diagnostic ignored "-Wsubobject-linkage"        // warning: 'xxxx' has a field 'xxxx' whose type uses the anonymous namespace
+#endif
+#endif
+
+//-------------------------------------------------------------------------
+// Data
+//-------------------------------------------------------------------------
+
+// Default memory allocators
+static void* ImGuiFreeTypeDefaultAllocFunc(size_t size, void* user_data) { IM_UNUSED(user_data); return IM_ALLOC(size); }
+static void  ImGuiFreeTypeDefaultFreeFunc(void* ptr, void* user_data) { IM_UNUSED(user_data); IM_FREE(ptr); }
+
+// Current memory allocators
+static void* (*GImGuiFreeTypeAllocFunc)(size_t size, void* user_data) = ImGuiFreeTypeDefaultAllocFunc;
+static void  (*GImGuiFreeTypeFreeFunc)(void* ptr, void* user_data) = ImGuiFreeTypeDefaultFreeFunc;
+static void* GImGuiFreeTypeAllocatorUserData = nullptr;
+
+// Lunasvg support
+#ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+static FT_Error ImGuiLunasvgPortInit(FT_Pointer* state);
+static void     ImGuiLunasvgPortFree(FT_Pointer* state);
+static FT_Error ImGuiLunasvgPortRender(FT_GlyphSlot slot, FT_Pointer* _state);
+static FT_Error ImGuiLunasvgPortPresetSlot(FT_GlyphSlot slot, FT_Bool cache, FT_Pointer* _state);
+#endif
+
+//-------------------------------------------------------------------------
+// Code
+//-------------------------------------------------------------------------
+
+namespace
+{
+    // Glyph metrics:
+    // --------------
+    //
+    //                       xmin                     xmax
+    //                        |                         |
+    //                        |<-------- width -------->|
+    //                        |                         |
+    //              |         +-------------------------+----------------- ymax
+    //              |         |    ggggggggg   ggggg    |     ^        ^
+    //              |         |   g:::::::::ggg::::g    |     |        |
+    //              |         |  g:::::::::::::::::g    |     |        |
+    //              |         | g::::::ggggg::::::gg    |     |        |
+    //              |         | g:::::g     g:::::g     |     |        |
+    //    offsetX  -|-------->| g:::::g     g:::::g     |  offsetY     |
+    //              |         | g:::::g     g:::::g     |     |        |
+    //              |         | g::::::g    g:::::g     |     |        |
+    //              |         | g:::::::ggggg:::::g     |     |        |
+    //              |         |  g::::::::::::::::g     |     |      height
+    //              |         |   gg::::::::::::::g     |     |        |
+    //  baseline ---*---------|---- gggggggg::::::g-----*--------      |
+    //            / |         |             g:::::g     |              |
+    //     origin   |         | gggggg      g:::::g     |              |
+    //              |         | g:::::gg   gg:::::g     |              |
+    //              |         |  g::::::ggg:::::::g     |              |
+    //              |         |   gg:::::::::::::g      |              |
+    //              |         |     ggg::::::ggg        |              |
+    //              |         |         gggggg          |              v
+    //              |         +-------------------------+----------------- ymin
+    //              |                                   |
+    //              |------------- advanceX ----------->|
+
+    // A structure that describe a glyph.
+    struct GlyphInfo
+    {
+        int         Width;              // Glyph's width in pixels.
+        int         Height;             // Glyph's height in pixels.
+        FT_Int      OffsetX;            // The distance from the origin ("pen position") to the left of the glyph.
+        FT_Int      OffsetY;            // The distance from the origin to the top of the glyph. This is usually a value < 0.
+        float       AdvanceX;           // The distance from the origin to the origin of the next glyph. This is usually a value > 0.
+        bool        IsColored;          // The glyph is colored
+    };
+
+    // Font parameters and metrics.
+    struct FontInfo
+    {
+        uint32_t    PixelHeight;        // Size this font was generated with.
+        float       Ascender;           // The pixel extents above the baseline in pixels (typically positive).
+        float       Descender;          // The extents below the baseline in pixels (typically negative).
+        float       LineSpacing;        // The baseline-to-baseline distance. Note that it usually is larger than the sum of the ascender and descender taken as absolute values. There is also no guarantee that no glyphs extend above or below subsequent baselines when using this distance. Think of it as a value the designer of the font finds appropriate.
+        float       LineGap;            // The spacing in pixels between one row's descent and the next row's ascent.
+        float       MaxAdvanceWidth;    // This field gives the maximum horizontal cursor advance for all glyphs in the font.
+    };
+
+    // FreeType glyph rasterizer.
+    // NB: No ctor/dtor, explicitly call Init()/Shutdown()
+    struct FreeTypeFont
+    {
+        bool                    InitFont(FT_Library ft_library, const ImFontConfig& cfg, unsigned int extra_user_flags); // Initialize from an external data buffer. Doesn't copy data, and you must ensure it stays valid up to this object lifetime.
+        void                    CloseFont();
+        void                    SetPixelHeight(int pixel_height); // Change font pixel size. All following calls to RasterizeGlyph() will use this size
+        const FT_Glyph_Metrics* LoadGlyph(uint32_t in_codepoint);
+        const FT_Bitmap*        RenderGlyphAndGetInfo(GlyphInfo* out_glyph_info);
+        void                    BlitGlyph(const FT_Bitmap* ft_bitmap, uint32_t* dst, uint32_t dst_pitch, unsigned char* multiply_table = nullptr);
+        ~FreeTypeFont()         { CloseFont(); }
+
+        // [Internals]
+        FontInfo        Info;               // Font descriptor of the current font.
+        FT_Face         Face;
+        unsigned int    UserFlags;          // = ImFontConfig::RasterizerFlags
+        FT_Int32        LoadFlags;
+        FT_Render_Mode  RenderMode;
+    };
+
+    // From SDL_ttf: Handy routines for converting from fixed point
+    #define FT_CEIL(X)  (((X + 63) & -64) / 64)
+
+    bool FreeTypeFont::InitFont(FT_Library ft_library, const ImFontConfig& cfg, unsigned int extra_font_builder_flags)
+    {
+        FT_Error error = FT_New_Memory_Face(ft_library, (uint8_t*)cfg.FontData, (uint32_t)cfg.FontDataSize, (uint32_t)cfg.FontNo, &Face);
+        if (error != 0)
+            return false;
+        error = FT_Select_Charmap(Face, FT_ENCODING_UNICODE);
+        if (error != 0)
+            return false;
+
+        // Convert to FreeType flags (NB: Bold and Oblique are processed separately)
+        UserFlags = cfg.FontBuilderFlags | extra_font_builder_flags;
+
+        LoadFlags = 0;
+        if ((UserFlags & ImGuiFreeTypeBuilderFlags_Bitmap) == 0)
+            LoadFlags |= FT_LOAD_NO_BITMAP;
+
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_NoHinting)
+            LoadFlags |= FT_LOAD_NO_HINTING;
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_NoAutoHint)
+            LoadFlags |= FT_LOAD_NO_AUTOHINT;
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_ForceAutoHint)
+            LoadFlags |= FT_LOAD_FORCE_AUTOHINT;
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_LightHinting)
+            LoadFlags |= FT_LOAD_TARGET_LIGHT;
+        else if (UserFlags & ImGuiFreeTypeBuilderFlags_MonoHinting)
+            LoadFlags |= FT_LOAD_TARGET_MONO;
+        else
+            LoadFlags |= FT_LOAD_TARGET_NORMAL;
+
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_Monochrome)
+            RenderMode = FT_RENDER_MODE_MONO;
+        else
+            RenderMode = FT_RENDER_MODE_NORMAL;
+
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_LoadColor)
+            LoadFlags |= FT_LOAD_COLOR;
+
+        memset(&Info, 0, sizeof(Info));
+        SetPixelHeight((uint32_t)cfg.SizePixels);
+
+        return true;
+    }
+
+    void FreeTypeFont::CloseFont()
+    {
+        if (Face)
+        {
+            FT_Done_Face(Face);
+            Face = nullptr;
+        }
+    }
+
+    void FreeTypeFont::SetPixelHeight(int pixel_height)
+    {
+        // Vuhdo: I'm not sure how to deal with font sizes properly. As far as I understand, currently ImGui assumes that the 'pixel_height'
+        // is a maximum height of an any given glyph, i.e. it's the sum of font's ascender and descender. Seems strange to me.
+        // NB: FT_Set_Pixel_Sizes() doesn't seem to get us the same result.
+        FT_Size_RequestRec req;
+        req.type = (UserFlags & ImGuiFreeTypeBuilderFlags_Bitmap) ? FT_SIZE_REQUEST_TYPE_NOMINAL : FT_SIZE_REQUEST_TYPE_REAL_DIM;
+        req.width = 0;
+        req.height = (uint32_t)pixel_height * 64;
+        req.horiResolution = 0;
+        req.vertResolution = 0;
+        FT_Request_Size(Face, &req);
+
+        // Update font info
+        FT_Size_Metrics metrics = Face->size->metrics;
+        Info.PixelHeight = (uint32_t)pixel_height;
+        Info.Ascender = (float)FT_CEIL(metrics.ascender);
+        Info.Descender = (float)FT_CEIL(metrics.descender);
+        Info.LineSpacing = (float)FT_CEIL(metrics.height);
+        Info.LineGap = (float)FT_CEIL(metrics.height - metrics.ascender + metrics.descender);
+        Info.MaxAdvanceWidth = (float)FT_CEIL(metrics.max_advance);
+    }
+
+    const FT_Glyph_Metrics* FreeTypeFont::LoadGlyph(uint32_t codepoint)
+    {
+        uint32_t glyph_index = FT_Get_Char_Index(Face, codepoint);
+        if (glyph_index == 0)
+            return nullptr;
+
+		// If this crash for you: FreeType 2.11.0 has a crash bug on some bitmap/colored fonts.
+		// - https://gitlab.freedesktop.org/freetype/freetype/-/issues/1076
+		// - https://github.com/ocornut/imgui/issues/4567
+		// - https://github.com/ocornut/imgui/issues/4566
+		// You can use FreeType 2.10, or the patched version of 2.11.0 in VcPkg, or probably any upcoming FreeType version.
+        FT_Error error = FT_Load_Glyph(Face, glyph_index, LoadFlags);
+        if (error)
+            return nullptr;
+
+        // Need an outline for this to work
+        FT_GlyphSlot slot = Face->glyph;
+#ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+        IM_ASSERT(slot->format == FT_GLYPH_FORMAT_OUTLINE || slot->format == FT_GLYPH_FORMAT_BITMAP || slot->format == FT_GLYPH_FORMAT_SVG);
+#else
+#if ((FREETYPE_MAJOR >= 2) && (FREETYPE_MINOR >= 12))
+        IM_ASSERT(slot->format != FT_GLYPH_FORMAT_SVG && "The font contains SVG glyphs, you'll need to enable IMGUI_ENABLE_FREETYPE_LUNASVG in imconfig.h and install required libraries in order to use this font");
+#endif
+        IM_ASSERT(slot->format == FT_GLYPH_FORMAT_OUTLINE || slot->format == FT_GLYPH_FORMAT_BITMAP);
+#endif // IMGUI_ENABLE_FREETYPE_LUNASVG
+
+        // Apply convenience transform (this is not picking from real "Bold"/"Italic" fonts! Merely applying FreeType helper transform. Oblique == Slanting)
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_Bold)
+            FT_GlyphSlot_Embolden(slot);
+        if (UserFlags & ImGuiFreeTypeBuilderFlags_Oblique)
+        {
+            FT_GlyphSlot_Oblique(slot);
+            //FT_BBox bbox;
+            //FT_Outline_Get_BBox(&slot->outline, &bbox);
+            //slot->metrics.width = bbox.xMax - bbox.xMin;
+            //slot->metrics.height = bbox.yMax - bbox.yMin;
+        }
+
+        return &slot->metrics;
+    }
+
+    const FT_Bitmap* FreeTypeFont::RenderGlyphAndGetInfo(GlyphInfo* out_glyph_info)
+    {
+        FT_GlyphSlot slot = Face->glyph;
+        FT_Error error = FT_Render_Glyph(slot, RenderMode);
+        if (error != 0)
+            return nullptr;
+
+        FT_Bitmap* ft_bitmap = &Face->glyph->bitmap;
+        out_glyph_info->Width = (int)ft_bitmap->width;
+        out_glyph_info->Height = (int)ft_bitmap->rows;
+        out_glyph_info->OffsetX = Face->glyph->bitmap_left;
+        out_glyph_info->OffsetY = -Face->glyph->bitmap_top;
+        out_glyph_info->AdvanceX = (float)FT_CEIL(slot->advance.x);
+        out_glyph_info->IsColored = (ft_bitmap->pixel_mode == FT_PIXEL_MODE_BGRA);
+
+        return ft_bitmap;
+    }
+
+    void FreeTypeFont::BlitGlyph(const FT_Bitmap* ft_bitmap, uint32_t* dst, uint32_t dst_pitch, unsigned char* multiply_table)
+    {
+        IM_ASSERT(ft_bitmap != nullptr);
+        const uint32_t w = ft_bitmap->width;
+        const uint32_t h = ft_bitmap->rows;
+        const uint8_t* src = ft_bitmap->buffer;
+        const uint32_t src_pitch = ft_bitmap->pitch;
+
+        switch (ft_bitmap->pixel_mode)
+        {
+        case FT_PIXEL_MODE_GRAY: // Grayscale image, 1 byte per pixel.
+            {
+                if (multiply_table == nullptr)
+                {
+                    for (uint32_t y = 0; y < h; y++, src += src_pitch, dst += dst_pitch)
+                        for (uint32_t x = 0; x < w; x++)
+                            dst[x] = IM_COL32(255, 255, 255, src[x]);
+                }
+                else
+                {
+                    for (uint32_t y = 0; y < h; y++, src += src_pitch, dst += dst_pitch)
+                        for (uint32_t x = 0; x < w; x++)
+                            dst[x] = IM_COL32(255, 255, 255, multiply_table[src[x]]);
+                }
+                break;
+            }
+        case FT_PIXEL_MODE_MONO: // Monochrome image, 1 bit per pixel. The bits in each byte are ordered from MSB to LSB.
+            {
+                uint8_t color0 = multiply_table ? multiply_table[0] : 0;
+                uint8_t color1 = multiply_table ? multiply_table[255] : 255;
+                for (uint32_t y = 0; y < h; y++, src += src_pitch, dst += dst_pitch)
+                {
+                    uint8_t bits = 0;
+                    const uint8_t* bits_ptr = src;
+                    for (uint32_t x = 0; x < w; x++, bits <<= 1)
+                    {
+                        if ((x & 7) == 0)
+                            bits = *bits_ptr++;
+                        dst[x] = IM_COL32(255, 255, 255, (bits & 0x80) ? color1 : color0);
+                    }
+                }
+                break;
+            }
+        case FT_PIXEL_MODE_BGRA:
+            {
+                // FIXME: Converting pre-multiplied alpha to straight. Doesn't smell good.
+                #define DE_MULTIPLY(color, alpha) (ImU32)(255.0f * (float)color / (float)alpha + 0.5f)
+                if (multiply_table == nullptr)
+                {
+                    for (uint32_t y = 0; y < h; y++, src += src_pitch, dst += dst_pitch)
+                        for (uint32_t x = 0; x < w; x++)
+                        {
+                            uint8_t r = src[x * 4 + 2], g = src[x * 4 + 1], b = src[x * 4], a = src[x * 4 + 3];
+                            dst[x] = IM_COL32(DE_MULTIPLY(r, a), DE_MULTIPLY(g, a), DE_MULTIPLY(b, a), a);
+                        }
+                }
+                else
+                {
+                    for (uint32_t y = 0; y < h; y++, src += src_pitch, dst += dst_pitch)
+                    {
+                        for (uint32_t x = 0; x < w; x++)
+                        {
+                            uint8_t r = src[x * 4 + 2], g = src[x * 4 + 1], b = src[x * 4], a = src[x * 4 + 3];
+                            dst[x] = IM_COL32(multiply_table[DE_MULTIPLY(r, a)], multiply_table[DE_MULTIPLY(g, a)], multiply_table[DE_MULTIPLY(b, a)], multiply_table[a]);
+                        }
+                    }
+                }
+                #undef DE_MULTIPLY
+                break;
+            }
+        default:
+            IM_ASSERT(0 && "FreeTypeFont::BlitGlyph(): Unknown bitmap pixel mode!");
+        }
+    }
+} // namespace
+
+#ifndef STB_RECT_PACK_IMPLEMENTATION                        // in case the user already have an implementation in the _same_ compilation unit (e.g. unity builds)
+#ifndef IMGUI_DISABLE_STB_RECT_PACK_IMPLEMENTATION
+#define STBRP_ASSERT(x)     do { IM_ASSERT(x); } while (0)
+#define STBRP_STATIC
+#define STB_RECT_PACK_IMPLEMENTATION
+#endif
+#ifdef IMGUI_STB_RECT_PACK_FILENAME
+#include IMGUI_STB_RECT_PACK_FILENAME
+#else
+#include "imstb_rectpack.h"
+#endif
+#endif
+
+struct ImFontBuildSrcGlyphFT
+{
+    GlyphInfo           Info;
+    uint32_t            Codepoint;
+    unsigned int*       BitmapData;         // Point within one of the dst_tmp_bitmap_buffers[] array
+
+    ImFontBuildSrcGlyphFT() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+struct ImFontBuildSrcDataFT
+{
+    FreeTypeFont        Font;
+    stbrp_rect*         Rects;              // Rectangle to pack. We first fill in their size and the packer will give us their position.
+    const ImWchar*      SrcRanges;          // Ranges as requested by user (user is allowed to request too much, e.g. 0x0020..0xFFFF)
+    int                 DstIndex;           // Index into atlas->Fonts[] and dst_tmp_array[]
+    int                 GlyphsHighest;      // Highest requested codepoint
+    int                 GlyphsCount;        // Glyph count (excluding missing glyphs and glyphs already set by an earlier source font)
+    ImBitVector         GlyphsSet;          // Glyph bit map (random access, 1-bit per codepoint. This will be a maximum of 8KB)
+    ImVector<ImFontBuildSrcGlyphFT>   GlyphsList;
+};
+
+// Temporary data for one destination ImFont* (multiple source fonts can be merged into one destination ImFont)
+struct ImFontBuildDstDataFT
+{
+    int                 SrcCount;           // Number of source fonts targeting this destination font.
+    int                 GlyphsHighest;
+    int                 GlyphsCount;
+    ImBitVector         GlyphsSet;          // This is used to resolve collision when multiple sources are merged into a same destination font.
+};
+
+bool ImFontAtlasBuildWithFreeTypeEx(FT_Library ft_library, ImFontAtlas* atlas, unsigned int extra_flags)
+{
+    IM_ASSERT(atlas->ConfigData.Size > 0);
+
+    ImFontAtlasBuildInit(atlas);
+
+    // Clear atlas
+    atlas->TexID = (ImTextureID)nullptr;
+    atlas->TexWidth = atlas->TexHeight = 0;
+    atlas->TexUvScale = ImVec2(0.0f, 0.0f);
+    atlas->TexUvWhitePixel = ImVec2(0.0f, 0.0f);
+    atlas->ClearTexData();
+
+    // Temporary storage for building
+    bool src_load_color = false;
+    ImVector<ImFontBuildSrcDataFT> src_tmp_array;
+    ImVector<ImFontBuildDstDataFT> dst_tmp_array;
+    src_tmp_array.resize(atlas->ConfigData.Size);
+    dst_tmp_array.resize(atlas->Fonts.Size);
+    memset((void*)src_tmp_array.Data, 0, (size_t)src_tmp_array.size_in_bytes());
+    memset((void*)dst_tmp_array.Data, 0, (size_t)dst_tmp_array.size_in_bytes());
+
+    // 1. Initialize font loading structure, check font data validity
+    for (int src_i = 0; src_i < atlas->ConfigData.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        ImFontConfig& cfg = atlas->ConfigData[src_i];
+        FreeTypeFont& font_face = src_tmp.Font;
+        IM_ASSERT(cfg.DstFont && (!cfg.DstFont->IsLoaded() || cfg.DstFont->ContainerAtlas == atlas));
+
+        // Find index from cfg.DstFont (we allow the user to set cfg.DstFont. Also it makes casual debugging nicer than when storing indices)
+        src_tmp.DstIndex = -1;
+        for (int output_i = 0; output_i < atlas->Fonts.Size && src_tmp.DstIndex == -1; output_i++)
+            if (cfg.DstFont == atlas->Fonts[output_i])
+                src_tmp.DstIndex = output_i;
+        IM_ASSERT(src_tmp.DstIndex != -1); // cfg.DstFont not pointing within atlas->Fonts[] array?
+        if (src_tmp.DstIndex == -1)
+            return false;
+
+        // Load font
+        if (!font_face.InitFont(ft_library, cfg, extra_flags))
+            return false;
+
+        // Measure highest codepoints
+        src_load_color |= (cfg.FontBuilderFlags & ImGuiFreeTypeBuilderFlags_LoadColor) != 0;
+        ImFontBuildDstDataFT& dst_tmp = dst_tmp_array[src_tmp.DstIndex];
+        src_tmp.SrcRanges = cfg.GlyphRanges ? cfg.GlyphRanges : atlas->GetGlyphRangesDefault();
+        for (const ImWchar* src_range = src_tmp.SrcRanges; src_range[0] && src_range[1]; src_range += 2)
+        {
+            // Check for valid range. This may also help detect *some* dangling pointers, because a common
+            // user error is to setup ImFontConfig::GlyphRanges with a pointer to data that isn't persistent.
+            IM_ASSERT(src_range[0] <= src_range[1]);
+            src_tmp.GlyphsHighest = ImMax(src_tmp.GlyphsHighest, (int)src_range[1]);
+        }
+        dst_tmp.SrcCount++;
+        dst_tmp.GlyphsHighest = ImMax(dst_tmp.GlyphsHighest, src_tmp.GlyphsHighest);
+    }
+
+    // 2. For every requested codepoint, check for their presence in the font data, and handle redundancy or overlaps between source fonts to avoid unused glyphs.
+    int total_glyphs_count = 0;
+    for (int src_i = 0; src_i < src_tmp_array.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        ImFontBuildDstDataFT& dst_tmp = dst_tmp_array[src_tmp.DstIndex];
+        src_tmp.GlyphsSet.Create(src_tmp.GlyphsHighest + 1);
+        if (dst_tmp.GlyphsSet.Storage.empty())
+            dst_tmp.GlyphsSet.Create(dst_tmp.GlyphsHighest + 1);
+
+        for (const ImWchar* src_range = src_tmp.SrcRanges; src_range[0] && src_range[1]; src_range += 2)
+            for (int codepoint = src_range[0]; codepoint <= (int)src_range[1]; codepoint++)
+            {
+                if (dst_tmp.GlyphsSet.TestBit(codepoint))    // Don't overwrite existing glyphs. We could make this an option (e.g. MergeOverwrite)
+                    continue;
+                uint32_t glyph_index = FT_Get_Char_Index(src_tmp.Font.Face, codepoint); // It is actually in the font? (FIXME-OPT: We are not storing the glyph_index..)
+                if (glyph_index == 0)
+                    continue;
+
+                // Add to avail set/counters
+                src_tmp.GlyphsCount++;
+                dst_tmp.GlyphsCount++;
+                src_tmp.GlyphsSet.SetBit(codepoint);
+                dst_tmp.GlyphsSet.SetBit(codepoint);
+                total_glyphs_count++;
+            }
+    }
+
+    // 3. Unpack our bit map into a flat list (we now have all the Unicode points that we know are requested _and_ available _and_ not overlapping another)
+    for (int src_i = 0; src_i < src_tmp_array.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        src_tmp.GlyphsList.reserve(src_tmp.GlyphsCount);
+
+        IM_ASSERT(sizeof(src_tmp.GlyphsSet.Storage.Data[0]) == sizeof(ImU32));
+        const ImU32* it_begin = src_tmp.GlyphsSet.Storage.begin();
+        const ImU32* it_end = src_tmp.GlyphsSet.Storage.end();
+        for (const ImU32* it = it_begin; it < it_end; it++)
+            if (ImU32 entries_32 = *it)
+                for (ImU32 bit_n = 0; bit_n < 32; bit_n++)
+                    if (entries_32 & ((ImU32)1 << bit_n))
+                    {
+                        ImFontBuildSrcGlyphFT src_glyph;
+                        src_glyph.Codepoint = (ImWchar)(((it - it_begin) << 5) + bit_n);
+                        //src_glyph.GlyphIndex = 0; // FIXME-OPT: We had this info in the previous step and lost it..
+                        src_tmp.GlyphsList.push_back(src_glyph);
+                    }
+        src_tmp.GlyphsSet.Clear();
+        IM_ASSERT(src_tmp.GlyphsList.Size == src_tmp.GlyphsCount);
+    }
+    for (int dst_i = 0; dst_i < dst_tmp_array.Size; dst_i++)
+        dst_tmp_array[dst_i].GlyphsSet.Clear();
+    dst_tmp_array.clear();
+
+    // Allocate packing character data and flag packed characters buffer as non-packed (x0=y0=x1=y1=0)
+    // (We technically don't need to zero-clear buf_rects, but let's do it for the sake of sanity)
+    ImVector<stbrp_rect> buf_rects;
+    buf_rects.resize(total_glyphs_count);
+    memset(buf_rects.Data, 0, (size_t)buf_rects.size_in_bytes());
+
+    // Allocate temporary rasterization data buffers.
+    // We could not find a way to retrieve accurate glyph size without rendering them.
+    // (e.g. slot->metrics->width not always matching bitmap->width, especially considering the Oblique transform)
+    // We allocate in chunks of 256 KB to not waste too much extra memory ahead. Hopefully users of FreeType won't mind the temporary allocations.
+    const int BITMAP_BUFFERS_CHUNK_SIZE = 256 * 1024;
+    int buf_bitmap_current_used_bytes = 0;
+    ImVector<unsigned char*> buf_bitmap_buffers;
+    buf_bitmap_buffers.push_back((unsigned char*)IM_ALLOC(BITMAP_BUFFERS_CHUNK_SIZE));
+
+    // 4. Gather glyphs sizes so we can pack them in our virtual canvas.
+    // 8. Render/rasterize font characters into the texture
+    int total_surface = 0;
+    int buf_rects_out_n = 0;
+    for (int src_i = 0; src_i < src_tmp_array.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        ImFontConfig& cfg = atlas->ConfigData[src_i];
+        if (src_tmp.GlyphsCount == 0)
+            continue;
+
+        src_tmp.Rects = &buf_rects[buf_rects_out_n];
+        buf_rects_out_n += src_tmp.GlyphsCount;
+
+        // Compute multiply table if requested
+        const bool multiply_enabled = (cfg.RasterizerMultiply != 1.0f);
+        unsigned char multiply_table[256];
+        if (multiply_enabled)
+            ImFontAtlasBuildMultiplyCalcLookupTable(multiply_table, cfg.RasterizerMultiply);
+
+        // Gather the sizes of all rectangles we will need to pack
+        const int padding = atlas->TexGlyphPadding;
+        for (int glyph_i = 0; glyph_i < src_tmp.GlyphsList.Size; glyph_i++)
+        {
+            ImFontBuildSrcGlyphFT& src_glyph = src_tmp.GlyphsList[glyph_i];
+
+            const FT_Glyph_Metrics* metrics = src_tmp.Font.LoadGlyph(src_glyph.Codepoint);
+            if (metrics == nullptr)
+                continue;
+
+            // Render glyph into a bitmap (currently held by FreeType)
+            const FT_Bitmap* ft_bitmap = src_tmp.Font.RenderGlyphAndGetInfo(&src_glyph.Info);
+            if (ft_bitmap == nullptr)
+                continue;
+
+            // Allocate new temporary chunk if needed
+            const int bitmap_size_in_bytes = src_glyph.Info.Width * src_glyph.Info.Height * 4;
+            if (buf_bitmap_current_used_bytes + bitmap_size_in_bytes > BITMAP_BUFFERS_CHUNK_SIZE)
+            {
+                buf_bitmap_current_used_bytes = 0;
+                buf_bitmap_buffers.push_back((unsigned char*)IM_ALLOC(BITMAP_BUFFERS_CHUNK_SIZE));
+            }
+            IM_ASSERT(buf_bitmap_current_used_bytes + bitmap_size_in_bytes <= BITMAP_BUFFERS_CHUNK_SIZE); // We could probably allocate custom-sized buffer instead.
+
+            // Blit rasterized pixels to our temporary buffer and keep a pointer to it.
+            src_glyph.BitmapData = (unsigned int*)(buf_bitmap_buffers.back() + buf_bitmap_current_used_bytes);
+            buf_bitmap_current_used_bytes += bitmap_size_in_bytes;
+            src_tmp.Font.BlitGlyph(ft_bitmap, src_glyph.BitmapData, src_glyph.Info.Width, multiply_enabled ? multiply_table : nullptr);
+
+            src_tmp.Rects[glyph_i].w = (stbrp_coord)(src_glyph.Info.Width + padding);
+            src_tmp.Rects[glyph_i].h = (stbrp_coord)(src_glyph.Info.Height + padding);
+            total_surface += src_tmp.Rects[glyph_i].w * src_tmp.Rects[glyph_i].h;
+        }
+    }
+
+    // We need a width for the skyline algorithm, any width!
+    // The exact width doesn't really matter much, but some API/GPU have texture size limitations and increasing width can decrease height.
+    // User can override TexDesiredWidth and TexGlyphPadding if they wish, otherwise we use a simple heuristic to select the width based on expected surface.
+    const int surface_sqrt = (int)ImSqrt((float)total_surface) + 1;
+    atlas->TexHeight = 0;
+    if (atlas->TexDesiredWidth > 0)
+        atlas->TexWidth = atlas->TexDesiredWidth;
+    else
+        atlas->TexWidth = (surface_sqrt >= 4096 * 0.7f) ? 4096 : (surface_sqrt >= 2048 * 0.7f) ? 2048 : (surface_sqrt >= 1024 * 0.7f) ? 1024 : 512;
+
+    // 5. Start packing
+    // Pack our extra data rectangles first, so it will be on the upper-left corner of our texture (UV will have small values).
+    const int TEX_HEIGHT_MAX = 1024 * 32;
+    const int num_nodes_for_packing_algorithm = atlas->TexWidth - atlas->TexGlyphPadding;
+    ImVector<stbrp_node> pack_nodes;
+    pack_nodes.resize(num_nodes_for_packing_algorithm);
+    stbrp_context pack_context;
+    stbrp_init_target(&pack_context, atlas->TexWidth - atlas->TexGlyphPadding, TEX_HEIGHT_MAX - atlas->TexGlyphPadding, pack_nodes.Data, pack_nodes.Size);
+    ImFontAtlasBuildPackCustomRects(atlas, &pack_context);
+
+    // 6. Pack each source font. No rendering yet, we are working with rectangles in an infinitely tall texture at this point.
+    for (int src_i = 0; src_i < src_tmp_array.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        if (src_tmp.GlyphsCount == 0)
+            continue;
+
+        stbrp_pack_rects(&pack_context, src_tmp.Rects, src_tmp.GlyphsCount);
+
+        // Extend texture height and mark missing glyphs as non-packed so we won't render them.
+        // FIXME: We are not handling packing failure here (would happen if we got off TEX_HEIGHT_MAX or if a single if larger than TexWidth?)
+        for (int glyph_i = 0; glyph_i < src_tmp.GlyphsCount; glyph_i++)
+            if (src_tmp.Rects[glyph_i].was_packed)
+                atlas->TexHeight = ImMax(atlas->TexHeight, src_tmp.Rects[glyph_i].y + src_tmp.Rects[glyph_i].h);
+    }
+
+    // 7. Allocate texture
+    atlas->TexHeight = (atlas->Flags & ImFontAtlasFlags_NoPowerOfTwoHeight) ? (atlas->TexHeight + 1) : ImUpperPowerOfTwo(atlas->TexHeight);
+    atlas->TexUvScale = ImVec2(1.0f / atlas->TexWidth, 1.0f / atlas->TexHeight);
+    if (src_load_color)
+    {
+        size_t tex_size = (size_t)atlas->TexWidth * atlas->TexHeight * 4;
+        atlas->TexPixelsRGBA32 = (unsigned int*)IM_ALLOC(tex_size);
+        memset(atlas->TexPixelsRGBA32, 0, tex_size);
+    }
+    else
+    {
+        size_t tex_size = (size_t)atlas->TexWidth * atlas->TexHeight * 1;
+        atlas->TexPixelsAlpha8 = (unsigned char*)IM_ALLOC(tex_size);
+        memset(atlas->TexPixelsAlpha8, 0, tex_size);
+    }
+
+    // 8. Copy rasterized font characters back into the main texture
+    // 9. Setup ImFont and glyphs for runtime
+    bool tex_use_colors = false;
+    for (int src_i = 0; src_i < src_tmp_array.Size; src_i++)
+    {
+        ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
+        if (src_tmp.GlyphsCount == 0)
+            continue;
+
+        // When merging fonts with MergeMode=true:
+        // - We can have multiple input fonts writing into a same destination font.
+        // - dst_font->ConfigData is != from cfg which is our source configuration.
+        ImFontConfig& cfg = atlas->ConfigData[src_i];
+        ImFont* dst_font = cfg.DstFont;
+
+        const float ascent = src_tmp.Font.Info.Ascender;
+        const float descent = src_tmp.Font.Info.Descender;
+        ImFontAtlasBuildSetupFont(atlas, dst_font, &cfg, ascent, descent);
+        const float font_off_x = cfg.GlyphOffset.x;
+        const float font_off_y = cfg.GlyphOffset.y + IM_ROUND(dst_font->Ascent);
+
+        const int padding = atlas->TexGlyphPadding;
+        for (int glyph_i = 0; glyph_i < src_tmp.GlyphsCount; glyph_i++)
+        {
+            ImFontBuildSrcGlyphFT& src_glyph = src_tmp.GlyphsList[glyph_i];
+            stbrp_rect& pack_rect = src_tmp.Rects[glyph_i];
+            IM_ASSERT(pack_rect.was_packed);
+            if (pack_rect.w == 0 && pack_rect.h == 0)
+                continue;
+
+            GlyphInfo& info = src_glyph.Info;
+            IM_ASSERT(info.Width + padding <= pack_rect.w);
+            IM_ASSERT(info.Height + padding <= pack_rect.h);
+            const int tx = pack_rect.x + padding;
+            const int ty = pack_rect.y + padding;
+
+            // Register glyph
+            float x0 = info.OffsetX + font_off_x;
+            float y0 = info.OffsetY + font_off_y;
+            float x1 = x0 + info.Width;
+            float y1 = y0 + info.Height;
+            float u0 = (tx) / (float)atlas->TexWidth;
+            float v0 = (ty) / (float)atlas->TexHeight;
+            float u1 = (tx + info.Width) / (float)atlas->TexWidth;
+            float v1 = (ty + info.Height) / (float)atlas->TexHeight;
+            dst_font->AddGlyph(&cfg, (ImWchar)src_glyph.Codepoint, x0, y0, x1, y1, u0, v0, u1, v1, info.AdvanceX);
+
+            ImFontGlyph* dst_glyph = &dst_font->Glyphs.back();
+            IM_ASSERT(dst_glyph->Codepoint == src_glyph.Codepoint);
+            if (src_glyph.Info.IsColored)
+                dst_glyph->Colored = tex_use_colors = true;
+
+            // Blit from temporary buffer to final texture
+            size_t blit_src_stride = (size_t)src_glyph.Info.Width;
+            size_t blit_dst_stride = (size_t)atlas->TexWidth;
+            unsigned int* blit_src = src_glyph.BitmapData;
+            if (atlas->TexPixelsAlpha8 != nullptr)
+            {
+                unsigned char* blit_dst = atlas->TexPixelsAlpha8 + (ty * blit_dst_stride) + tx;
+                for (int y = 0; y < info.Height; y++, blit_dst += blit_dst_stride, blit_src += blit_src_stride)
+                    for (int x = 0; x < info.Width; x++)
+                        blit_dst[x] = (unsigned char)((blit_src[x] >> IM_COL32_A_SHIFT) & 0xFF);
+            }
+            else
+            {
+                unsigned int* blit_dst = atlas->TexPixelsRGBA32 + (ty * blit_dst_stride) + tx;
+                for (int y = 0; y < info.Height; y++, blit_dst += blit_dst_stride, blit_src += blit_src_stride)
+                    for (int x = 0; x < info.Width; x++)
+                        blit_dst[x] = blit_src[x];
+            }
+        }
+
+        src_tmp.Rects = nullptr;
+    }
+    atlas->TexPixelsUseColors = tex_use_colors;
+
+    // Cleanup
+    for (int buf_i = 0; buf_i < buf_bitmap_buffers.Size; buf_i++)
+        IM_FREE(buf_bitmap_buffers[buf_i]);
+    src_tmp_array.clear_destruct();
+
+    ImFontAtlasBuildFinish(atlas);
+
+    return true;
+}
+
+// FreeType memory allocation callbacks
+static void* FreeType_Alloc(FT_Memory /*memory*/, long size)
+{
+    return GImGuiFreeTypeAllocFunc((size_t)size, GImGuiFreeTypeAllocatorUserData);
+}
+
+static void FreeType_Free(FT_Memory /*memory*/, void* block)
+{
+    GImGuiFreeTypeFreeFunc(block, GImGuiFreeTypeAllocatorUserData);
+}
+
+static void* FreeType_Realloc(FT_Memory /*memory*/, long cur_size, long new_size, void* block)
+{
+    // Implement realloc() as we don't ask user to provide it.
+    if (block == nullptr)
+        return GImGuiFreeTypeAllocFunc((size_t)new_size, GImGuiFreeTypeAllocatorUserData);
+
+    if (new_size == 0)
+    {
+        GImGuiFreeTypeFreeFunc(block, GImGuiFreeTypeAllocatorUserData);
+        return nullptr;
+    }
+
+    if (new_size > cur_size)
+    {
+        void* new_block = GImGuiFreeTypeAllocFunc((size_t)new_size, GImGuiFreeTypeAllocatorUserData);
+        memcpy(new_block, block, (size_t)cur_size);
+        GImGuiFreeTypeFreeFunc(block, GImGuiFreeTypeAllocatorUserData);
+        return new_block;
+    }
+
+    return block;
+}
+
+static bool ImFontAtlasBuildWithFreeType(ImFontAtlas* atlas)
+{
+    // FreeType memory management: https://www.freetype.org/freetype2/docs/design/design-4.html
+    FT_MemoryRec_ memory_rec = {};
+    memory_rec.user = nullptr;
+    memory_rec.alloc = &FreeType_Alloc;
+    memory_rec.free = &FreeType_Free;
+    memory_rec.realloc = &FreeType_Realloc;
+
+    // https://www.freetype.org/freetype2/docs/reference/ft2-module_management.html#FT_New_Library
+    FT_Library ft_library;
+    FT_Error error = FT_New_Library(&memory_rec, &ft_library);
+    if (error != 0)
+        return false;
+
+    // If you don't call FT_Add_Default_Modules() the rest of code may work, but FreeType won't use our custom allocator.
+    FT_Add_Default_Modules(ft_library);
+
+#ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+    // Install svg hooks for FreeType
+    // https://freetype.org/freetype2/docs/reference/ft2-properties.html#svg-hooks
+    // https://freetype.org/freetype2/docs/reference/ft2-svg_fonts.html#svg_fonts
+    SVG_RendererHooks hooks = { ImGuiLunasvgPortInit, ImGuiLunasvgPortFree, ImGuiLunasvgPortRender, ImGuiLunasvgPortPresetSlot };
+    FT_Property_Set(ft_library, "ot-svg", "svg-hooks", &hooks);
+#endif // IMGUI_ENABLE_FREETYPE_LUNASVG
+
+    bool ret = ImFontAtlasBuildWithFreeTypeEx(ft_library, atlas, atlas->FontBuilderFlags);
+    FT_Done_Library(ft_library);
+
+    return ret;
+}
+
+const ImFontBuilderIO* ImGuiFreeType::GetBuilderForFreeType()
+{
+    static ImFontBuilderIO io;
+    io.FontBuilder_Build = ImFontAtlasBuildWithFreeType;
+    return &io;
+}
+
+void ImGuiFreeType::SetAllocatorFunctions(void* (*alloc_func)(size_t sz, void* user_data), void (*free_func)(void* ptr, void* user_data), void* user_data)
+{
+    GImGuiFreeTypeAllocFunc = alloc_func;
+    GImGuiFreeTypeFreeFunc = free_func;
+    GImGuiFreeTypeAllocatorUserData = user_data;
+}
+
+#ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+// For more details, see https://gitlab.freedesktop.org/freetype/freetype-demos/-/blob/master/src/rsvg-port.c
+// The original code from the demo is licensed under CeCILL-C Free Software License Agreement (https://gitlab.freedesktop.org/freetype/freetype/-/blob/master/LICENSE.TXT)
+struct LunasvgPortState
+{
+    FT_Error            err = FT_Err_Ok;
+    lunasvg::Matrix     matrix;
+    std::unique_ptr<lunasvg::Document> svg = nullptr;
+};
+
+static FT_Error ImGuiLunasvgPortInit(FT_Pointer* _state)
+{
+    *_state = IM_NEW(LunasvgPortState)();
+    return FT_Err_Ok;
+}
+
+static void ImGuiLunasvgPortFree(FT_Pointer* _state)
+{
+    IM_DELETE(*(LunasvgPortState**)_state);
+}
+
+static FT_Error ImGuiLunasvgPortRender(FT_GlyphSlot slot, FT_Pointer* _state)
+{
+    LunasvgPortState* state = *(LunasvgPortState**)_state;
+
+    // If there was an error while loading the svg in ImGuiLunasvgPortPresetSlot(), the renderer hook still get called, so just returns the error.
+    if (state->err != FT_Err_Ok)
+        return state->err;
+
+    // rows is height, pitch (or stride) equals to width * sizeof(int32)
+    lunasvg::Bitmap bitmap((uint8_t*)slot->bitmap.buffer, slot->bitmap.width, slot->bitmap.rows, slot->bitmap.pitch);
+    state->svg->setMatrix(state->svg->matrix().identity()); // Reset the svg matrix to the default value
+    state->svg->render(bitmap, state->matrix);              // state->matrix is already scaled and translated
+    state->err = FT_Err_Ok;
+    return state->err;
+}
+
+static FT_Error ImGuiLunasvgPortPresetSlot(FT_GlyphSlot slot, FT_Bool cache, FT_Pointer* _state)
+{
+    FT_SVG_Document   document = (FT_SVG_Document)slot->other;
+    LunasvgPortState* state = *(LunasvgPortState**)_state;
+    FT_Size_Metrics&  metrics = document->metrics;
+
+    // This function is called twice, once in the FT_Load_Glyph() and another right before ImGuiLunasvgPortRender().
+    // If it's the latter, don't do anything because it's // already done in the former.
+    if (cache)
+        return state->err;
+
+    state->svg = lunasvg::Document::loadFromData((const char*)document->svg_document, document->svg_document_length);
+    if (state->svg == nullptr)
+    {
+        state->err = FT_Err_Invalid_SVG_Document;
+        return state->err;
+    }
+
+    lunasvg::Box box = state->svg->box();
+    double scale = std::min(metrics.x_ppem / box.w, metrics.y_ppem / box.h);
+    double xx = (double)document->transform.xx / (1 << 16);
+    double xy = -(double)document->transform.xy / (1 << 16);
+    double yx = -(double)document->transform.yx / (1 << 16);
+    double yy = (double)document->transform.yy / (1 << 16);
+    double x0 = (double)document->delta.x / 64 * box.w / metrics.x_ppem;
+    double y0 = -(double)document->delta.y / 64 * box.h / metrics.y_ppem;
+
+    // Scale and transform, we don't translate the svg yet
+    state->matrix.identity();
+    state->matrix.scale(scale, scale);
+    state->matrix.transform(xx, xy, yx, yy, x0, y0);
+    state->svg->setMatrix(state->matrix);
+
+    // Pre-translate the matrix for the rendering step
+    state->matrix.translate(-box.x, -box.y);
+
+    // Get the box again after the transformation
+    box = state->svg->box();
+
+    // Calculate the bitmap size
+    slot->bitmap_left = FT_Int(box.x);
+    slot->bitmap_top = FT_Int(-box.y);
+    slot->bitmap.rows = (unsigned int)(ImCeil((float)box.h));
+    slot->bitmap.width = (unsigned int)(ImCeil((float)box.w));
+    slot->bitmap.pitch = slot->bitmap.width * 4;
+    slot->bitmap.pixel_mode = FT_PIXEL_MODE_BGRA;
+
+    // Compute all the bearings and set them correctly. The outline is scaled already, we just need to use the bounding box.
+    double metrics_width = box.w;
+    double metrics_height = box.h;
+    double horiBearingX = box.x;
+    double horiBearingY = -box.y;
+    double vertBearingX = slot->metrics.horiBearingX / 64.0 - slot->metrics.horiAdvance / 64.0 / 2.0;
+    double vertBearingY = (slot->metrics.vertAdvance / 64.0 - slot->metrics.height / 64.0) / 2.0;
+    slot->metrics.width = FT_Pos(IM_ROUND(metrics_width * 64.0));   // Using IM_ROUND() assume width and height are positive
+    slot->metrics.height = FT_Pos(IM_ROUND(metrics_height * 64.0));
+    slot->metrics.horiBearingX = FT_Pos(horiBearingX * 64);
+    slot->metrics.horiBearingY = FT_Pos(horiBearingY * 64);
+    slot->metrics.vertBearingX = FT_Pos(vertBearingX * 64);
+    slot->metrics.vertBearingY = FT_Pos(vertBearingY * 64);
+
+    if (slot->metrics.vertAdvance == 0)
+        slot->metrics.vertAdvance = FT_Pos(metrics_height * 1.2 * 64.0);
+
+    state->err = FT_Err_Ok;
+    return state->err;
+}
+
+#endif // #ifdef IMGUI_ENABLE_FREETYPE_LUNASVG
+
+//-----------------------------------------------------------------------------
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif
+
+#ifdef _MSC_VER
+#pragma warning (pop)
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/misc/freetype/imgui_freetype.h

@@ -0,0 +1,52 @@
+// dear imgui: FreeType font builder (used as a replacement for the stb_truetype builder)
+// (headers)
+
+#pragma once
+#include "imgui.h"      // IMGUI_API
+#ifndef IMGUI_DISABLE
+
+// Forward declarations
+struct ImFontAtlas;
+struct ImFontBuilderIO;
+
+// Hinting greatly impacts visuals (and glyph sizes).
+// - By default, hinting is enabled and the font's native hinter is preferred over the auto-hinter.
+// - When disabled, FreeType generates blurrier glyphs, more or less matches the stb_truetype.h
+// - The Default hinting mode usually looks good, but may distort glyphs in an unusual way.
+// - The Light hinting mode generates fuzzier glyphs but better matches Microsoft's rasterizer.
+// You can set those flags globaly in ImFontAtlas::FontBuilderFlags
+// You can set those flags on a per font basis in ImFontConfig::FontBuilderFlags
+enum ImGuiFreeTypeBuilderFlags
+{
+    ImGuiFreeTypeBuilderFlags_NoHinting     = 1 << 0,   // Disable hinting. This generally generates 'blurrier' bitmap glyphs when the glyph are rendered in any of the anti-aliased modes.
+    ImGuiFreeTypeBuilderFlags_NoAutoHint    = 1 << 1,   // Disable auto-hinter.
+    ImGuiFreeTypeBuilderFlags_ForceAutoHint = 1 << 2,   // Indicates that the auto-hinter is preferred over the font's native hinter.
+    ImGuiFreeTypeBuilderFlags_LightHinting  = 1 << 3,   // A lighter hinting algorithm for gray-level modes. Many generated glyphs are fuzzier but better resemble their original shape. This is achieved by snapping glyphs to the pixel grid only vertically (Y-axis), as is done by Microsoft's ClearType and Adobe's proprietary font renderer. This preserves inter-glyph spacing in horizontal text.
+    ImGuiFreeTypeBuilderFlags_MonoHinting   = 1 << 4,   // Strong hinting algorithm that should only be used for monochrome output.
+    ImGuiFreeTypeBuilderFlags_Bold          = 1 << 5,   // Styling: Should we artificially embolden the font?
+    ImGuiFreeTypeBuilderFlags_Oblique       = 1 << 6,   // Styling: Should we slant the font, emulating italic style?
+    ImGuiFreeTypeBuilderFlags_Monochrome    = 1 << 7,   // Disable anti-aliasing. Combine this with MonoHinting for best results!
+    ImGuiFreeTypeBuilderFlags_LoadColor     = 1 << 8,   // Enable FreeType color-layered glyphs
+    ImGuiFreeTypeBuilderFlags_Bitmap        = 1 << 9    // Enable FreeType bitmap glyphs
+};
+
+namespace ImGuiFreeType
+{
+    // This is automatically assigned when using '#define IMGUI_ENABLE_FREETYPE'.
+    // If you need to dynamically select between multiple builders:
+    // - you can manually assign this builder with 'atlas->FontBuilderIO = ImGuiFreeType::GetBuilderForFreeType()'
+    // - prefer deep-copying this into your own ImFontBuilderIO instance if you use hot-reloading that messes up static data.
+    IMGUI_API const ImFontBuilderIO*    GetBuilderForFreeType();
+
+    // Override allocators. By default ImGuiFreeType will use IM_ALLOC()/IM_FREE()
+    // However, as FreeType does lots of allocations we provide a way for the user to redirect it to a separate memory heap if desired.
+    IMGUI_API void                      SetAllocatorFunctions(void* (*alloc_func)(size_t sz, void* user_data), void (*free_func)(void* ptr, void* user_data), void* user_data = nullptr);
+
+    // Obsolete names (will be removed soon)
+    // Prefer using '#define IMGUI_ENABLE_FREETYPE'
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    static inline bool BuildFontAtlas(ImFontAtlas* atlas, unsigned int flags = 0) { atlas->FontBuilderIO = GetBuilderForFreeType(); atlas->FontBuilderFlags = flags; return atlas->Build(); }
+#endif
+}
+
+#endif // #ifndef IMGUI_DISABLE

ext/imgui/misc/single_file/imgui_single_file.h

@@ -0,0 +1,29 @@
+// dear imgui: single-file wrapper include
+// We use this to validate compiling all *.cpp files in a same compilation unit.
+// Users of that technique (also called "Unity builds") can generally provide this themselves,
+// so we don't really recommend you use this in your projects.
+
+// Do this:
+//    #define IMGUI_IMPLEMENTATION
+// Before you include this file in *one* C++ file to create the implementation.
+// Using this in your project will leak the contents of imgui_internal.h and ImVec2 operators in this compilation unit.
+
+#ifdef IMGUI_IMPLEMENTATION
+#define IMGUI_DEFINE_MATH_OPERATORS
+#endif
+
+#include "../../imgui.h"
+#ifdef IMGUI_ENABLE_FREETYPE
+#include "../../misc/freetype/imgui_freetype.h"
+#endif
+
+#ifdef IMGUI_IMPLEMENTATION
+#include "../../imgui.cpp"
+#include "../../imgui_demo.cpp"
+#include "../../imgui_draw.cpp"
+#include "../../imgui_tables.cpp"
+#include "../../imgui_widgets.cpp"
+#ifdef IMGUI_ENABLE_FREETYPE
+#include "../../misc/freetype/imgui_freetype.cpp"
+#endif
+#endif

fonts/B612_Mono/OFL.txt

@@ -0,0 +1,93 @@
+Copyright 2012 The B612 Project Authors (https://github.com/polarsys/b612)
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.