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third_party/imgui/docs/EXAMPLES.md

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+_(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.
+
+You can find Windows binaries for some of those example applications at:
+  http://www.dearimgui.org/binaries
+
+
+### Getting Started
+
+Integration in a typical existing application, should take <20 lines when using standard backends.
+
+    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)):
+
+    // 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 http://www.dearimgui.org/faq
+
+If you are using of the backend 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_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_emscripten_opengl3/) <BR>
+Emcripten + SDL2 + OpenGL3+/ES2/ES3 example. <BR>
+= main.cpp + imgui_impl_sdl.cpp + imgui_impl_opengl3.cpp <BR>
+Note that other examples based on SDL or GLFW + OpenGL could easily be modified to work with Emscripten.
+We provide this to make the Emscripten differences obvious, and have them not pollute all other examples.
+
+[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
+
+[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 OPENGL2 CODE IF YOUR CODE/ENGINE IS USING MODERN OPENGL (SHADERS, VBO, VAO, etc.)** <BR>
+**Prefer using OPENGL3 code (with gl3w/glew/glad/glad2/glbinding, you can replace the OpenGL function loader)** <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 OpenGL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many OpenGL 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 (programmable pipeline). <BR>
+= main.cpp + imgui_impl_glfw.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern OpenGL calls and custom shaders. <BR>
+Prefer using that if you are using modern OpenGL in your application (anything with shaders).
+(Please be mindful that accessing OpenGL3+ functions requires a function loader, which are a frequent
+source for confusion for new users. We use a loader in imgui_impl_opengl3.cpp which may be different
+from the one your app normally use. Read imgui_impl_opengl3.h for details and how to change it.)
+
+[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_marmalade/](https://github.com/ocornut/imgui/blob/master/examples/example_marmalade/) <BR>
+Marmalade example using IwGx. <BR>
+= main.cpp + imgui_impl_marmalade.cpp
+
+[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_sdl_directx11/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl_directx11/) <BR>
+SDL2 + DirectX11 example, Windows only. <BR>
+= main.cpp + imgui_impl_sdl.cpp + imgui_impl_dx11.cpp <BR>
+This to demonstrate usage of DirectX with SDL.
+
+[example_sdl_metal/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl_metal/) <BR>
+SDL2 (Mac) + Metal example. <BR>
+= main.mm + imgui_impl_sdl.cpp + imgui_impl_metal.mm
+
+[example_sdl_opengl2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl_opengl2/) <BR>
+SDL2 (Win32, Mac, Linux etc.) + OpenGL example (legacy, fixed pipeline). <BR>
+= main.cpp + imgui_impl_sdl.cpp + imgui_impl_opengl2.cpp <BR>
+**DO NOT USE OPENGL2 CODE IF YOUR CODE/ENGINE IS USING MODERN OPENGL (SHADERS, VBO, VAO, etc.)** <BR>
+**Prefer using OPENGL3 code (with gl3w/glew/glad/glad2/glbinding, you can replace the OpenGL function loader)** <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 OpenGL calls, using this renderer is likely to
+make things more complicated, will require your code to reset many OpenGL attributes to their initial
+state, and might confuse your GPU driver. One star, not recommended.
+
+[example_sdl_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl_opengl3/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + OpenGL3+/ES2/ES3 example. <BR>
+= main.cpp + imgui_impl_sdl.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern OpenGL calls and custom shaders. <BR>
+Prefer using that if you are using modern OpenGL in your application (anything with shaders).
+(Please be mindful that accessing OpenGL3+ functions requires a function loader, which are a frequent
+source for confusion for new users. We use a loader in imgui_impl_opengl3.cpp which may be different
+from the one your app normally use. Read imgui_impl_opengl3.h for details and how to change it.)
+
+[example_sdl_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl_vulkan/) <BR>
+SDL2 (Win32, Mac, Linux, etc.) + Vulkan example. <BR>
+= main.cpp + imgui_impl_sdl.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.
+
+
+### Miscallaneous
+
+**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 value of 'io.MousePos' provided at the time of 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!
+