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src/imgui/imgui_impl_opengl3.h

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+// dear imgui: Renderer for modern OpenGL with shaders / programmatic pipeline
+// - Desktop GL: 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 Binding (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 in imgui.cpp.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
+// If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
+// https://github.com/ocornut/imgui
+
+// About Desktop OpenGL function loaders:
+//  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 supporting a few common ones (gl3w, glew, glad).
+//  You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
+
+// About GLSL version:
+//  The 'glsl_version' initialization parameter should be NULL (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
+
+// Specific OpenGL versions
+//#define IMGUI_IMPL_OPENGL_ES2     // Auto-detected on Emscripten
+//#define IMGUI_IMPL_OPENGL_ES3     // Auto-detected on iOS/Android
+
+#include "imgui.h"
+
+#define IMGUI_IMPL_OPENGL_LOADER_CUSTOM "glext.h"
+#include "Common/GLInclude/GLInclude.h"
+
+// Set default OpenGL3 loader to be gl3w
+#if !defined(IMGUI_IMPL_OPENGL_LOADER_GL3W)     \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLEW)     \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLAD)     \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM)
+#define IMGUI_IMPL_OPENGL_LOADER_GL3W
+#endif
+
+#undef IMGUI_IMPL_OPENGL_LOADER_GL3W
+
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_Init(const char* glsl_version = NULL);
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data);
+
+// 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();