// dear imgui: standalone example application for SDL2 + OpenGL // If you are new to dear imgui, see examples/README.txt and documentation at the top of imgui.cpp. // (SDL is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.) // (GL3W is a helper library to access OpenGL functions since there is no standard header to access modern OpenGL functions easily. Alternatives are GLEW, Glad, etc.) #include "imgui.h" #include "imgui_impl_sdl.h" #include "imgui_impl_opengl3.h" #include #include // About OpenGL function loaders: modern OpenGL doesn't have a standard header file and requires individual function pointers to be loaded manually. // 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. #if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W) #include // Initialize with gl3wInit() #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW) #include // Initialize with glewInit() #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD) #include // Initialize with gladLoadGL() #else #include IMGUI_IMPL_OPENGL_LOADER_CUSTOM #endif int main(int, char**) { // Setup SDL if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER) != 0) { printf("Error: %s\n", SDL_GetError()); return -1; } // Decide GL+GLSL versions #if __APPLE__ // GL 3.2 Core + GLSL 150 const char* glsl_version = "#version 150"; SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG); // Always required on Mac SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE); SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3); SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2); #else // GL 3.0 + GLSL 130 const char* glsl_version = "#version 130"; SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0); SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE); SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3); SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0); #endif // Create window with graphics context SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24); SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8); SDL_DisplayMode current; SDL_GetCurrentDisplayMode(0, ¤t); SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+OpenGL3 example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE); SDL_GLContext gl_context = SDL_GL_CreateContext(window); SDL_GL_SetSwapInterval(1); // Enable vsync // Initialize OpenGL loader #if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W) bool err = gl3wInit() != 0; #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW) bool err = glewInit() != GLEW_OK; #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD) bool err = gladLoadGL() == 0; #endif if (err) { fprintf(stderr, "Failed to initialize OpenGL loader!\n"); return 1; } // Setup Dear ImGui binding IMGUI_CHECKVERSION(); ImGui::CreateContext(); ImGuiIO& io = ImGui::GetIO(); (void)io; //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable Keyboard Controls ImGui_ImplSDL2_InitForOpenGL(window, gl_context); ImGui_ImplOpenGL3_Init(glsl_version); // Setup style ImGui::StyleColorsDark(); //ImGui::StyleColorsClassic(); // Load Fonts // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them. // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple. // - If the file cannot be loaded, the function will return NULL. Please handle those errors in your application (e.g. use an assertion, or display an error and quit). // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call. // - Read 'misc/fonts/README.txt' for more instructions and details. // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ ! //io.Fonts->AddFontDefault(); //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f); //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f); //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f); //io.Fonts->AddFontFromFileTTF("../../misc/fonts/ProggyTiny.ttf", 10.0f); //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese()); //IM_ASSERT(font != NULL); bool show_demo_window = true; bool show_another_window = false; ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f); // Main loop bool done = false; while (!done) { // Poll and handle events (inputs, window resize, etc.) // 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. // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application. // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags. SDL_Event event; while (SDL_PollEvent(&event)) { ImGui_ImplSDL2_ProcessEvent(&event); if (event.type == SDL_QUIT) done = true; if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window)) done = true; } // Start the Dear ImGui frame ImGui_ImplOpenGL3_NewFrame(); ImGui_ImplSDL2_NewFrame(window); ImGui::NewFrame(); // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!). if (show_demo_window) ImGui::ShowDemoWindow(&show_demo_window); // 2. Show a simple window that we create ourselves. We use a Begin/End pair to created a named window. { static float f = 0.0f; static int counter = 0; ImGui::Begin("Hello, world!"); // Create a window called "Hello, world!" and append into it. ImGui::Text("This is some useful text."); // Display some text (you can use a format strings too) ImGui::Checkbox("Demo Window", &show_demo_window); // Edit bools storing our window open/close state ImGui::Checkbox("Another Window", &show_another_window); ImGui::SliderFloat("float", &f, 0.0f, 1.0f); // Edit 1 float using a slider from 0.0f to 1.0f ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color if (ImGui::Button("Button")) // Buttons return true when clicked (most widgets return true when edited/activated) counter++; ImGui::SameLine(); ImGui::Text("counter = %d", counter); ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate); ImGui::End(); } // 3. Show another simple window. if (show_another_window) { ImGui::Begin("Another Window", &show_another_window); // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked) ImGui::Text("Hello from another window!"); if (ImGui::Button("Close Me")) show_another_window = false; ImGui::End(); } // Rendering ImGui::Render(); SDL_GL_MakeCurrent(window, gl_context); glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y); glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w); glClear(GL_COLOR_BUFFER_BIT); ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData()); SDL_GL_SwapWindow(window); } // Cleanup ImGui_ImplOpenGL3_Shutdown(); ImGui_ImplSDL2_Shutdown(); ImGui::DestroyContext(); SDL_GL_DeleteContext(gl_context); SDL_DestroyWindow(window); SDL_Quit(); return 0; } 48 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199