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+_(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.