main.cpp (7780B)
1 // Dear ImGui: standalone example application for SDL2 + OpenGL 2 // (SDL is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan/Metal graphics context creation, etc.) 3 // If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp. 4 // Read online: https://github.com/ocornut/imgui/tree/master/docs 5 6 // **DO NOT USE THIS CODE IF YOUR CODE/ENGINE IS USING MODERN OPENGL (SHADERS, VBO, VAO, etc.)** 7 // **Prefer using the code in the example_sdl_opengl3/ folder** 8 // See imgui_impl_sdl.cpp for details. 9 10 #include "imgui.h" 11 #include "imgui_impl_sdl.h" 12 #include "imgui_impl_opengl2.h" 13 #include <stdio.h> 14 #include <SDL.h> 15 #include <SDL_opengl.h> 16 17 // Main code 18 int main(int, char**) 19 { 20 // Setup SDL 21 // (Some versions of SDL before <2.0.10 appears to have performance/stalling issues on a minority of Windows systems, 22 // depending on whether SDL_INIT_GAMECONTROLLER is enabled or disabled.. updating to latest version of SDL is recommended!) 23 if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMECONTROLLER) != 0) 24 { 25 printf("Error: %s\n", SDL_GetError()); 26 return -1; 27 } 28 29 // Setup window 30 SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); 31 SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24); 32 SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8); 33 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2); 34 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2); 35 SDL_WindowFlags window_flags = (SDL_WindowFlags)(SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI); 36 SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, window_flags); 37 SDL_GLContext gl_context = SDL_GL_CreateContext(window); 38 SDL_GL_MakeCurrent(window, gl_context); 39 SDL_GL_SetSwapInterval(1); // Enable vsync 40 41 // Setup Dear ImGui context 42 IMGUI_CHECKVERSION(); 43 ImGui::CreateContext(); 44 ImGuiIO& io = ImGui::GetIO(); (void)io; 45 //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable Keyboard Controls 46 //io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad; // Enable Gamepad Controls 47 48 // Setup Dear ImGui style 49 ImGui::StyleColorsDark(); 50 //ImGui::StyleColorsClassic(); 51 52 // Setup Platform/Renderer backends 53 ImGui_ImplSDL2_InitForOpenGL(window, gl_context); 54 ImGui_ImplOpenGL2_Init(); 55 56 // Load Fonts 57 // - 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. 58 // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple. 59 // - 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). 60 // - 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. 61 // - Read 'docs/FONTS.md' for more instructions and details. 62 // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ ! 63 //io.Fonts->AddFontDefault(); 64 //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f); 65 //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f); 66 //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f); 67 //io.Fonts->AddFontFromFileTTF("../../misc/fonts/ProggyTiny.ttf", 10.0f); 68 //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese()); 69 //IM_ASSERT(font != NULL); 70 71 // Our state 72 bool show_demo_window = true; 73 bool show_another_window = false; 74 ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f); 75 76 // Main loop 77 bool done = false; 78 while (!done) 79 { 80 // Poll and handle events (inputs, window resize, etc.) 81 // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs. 82 // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application. 83 // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application. 84 // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags. 85 SDL_Event event; 86 while (SDL_PollEvent(&event)) 87 { 88 ImGui_ImplSDL2_ProcessEvent(&event); 89 if (event.type == SDL_QUIT) 90 done = true; 91 if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window)) 92 done = true; 93 } 94 95 // Start the Dear ImGui frame 96 ImGui_ImplOpenGL2_NewFrame(); 97 ImGui_ImplSDL2_NewFrame(window); 98 ImGui::NewFrame(); 99 100 // 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!). 101 if (show_demo_window) 102 ImGui::ShowDemoWindow(&show_demo_window); 103 104 // 2. Show a simple window that we create ourselves. We use a Begin/End pair to created a named window. 105 { 106 static float f = 0.0f; 107 static int counter = 0; 108 109 ImGui::Begin("Hello, world!"); // Create a window called "Hello, world!" and append into it. 110 111 ImGui::Text("This is some useful text."); // Display some text (you can use a format strings too) 112 ImGui::Checkbox("Demo Window", &show_demo_window); // Edit bools storing our window open/close state 113 ImGui::Checkbox("Another Window", &show_another_window); 114 115 ImGui::SliderFloat("float", &f, 0.0f, 1.0f); // Edit 1 float using a slider from 0.0f to 1.0f 116 ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color 117 118 if (ImGui::Button("Button")) // Buttons return true when clicked (most widgets return true when edited/activated) 119 counter++; 120 ImGui::SameLine(); 121 ImGui::Text("counter = %d", counter); 122 123 ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate); 124 ImGui::End(); 125 } 126 127 // 3. Show another simple window. 128 if (show_another_window) 129 { 130 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) 131 ImGui::Text("Hello from another window!"); 132 if (ImGui::Button("Close Me")) 133 show_another_window = false; 134 ImGui::End(); 135 } 136 137 // Rendering 138 ImGui::Render(); 139 glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y); 140 glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w); 141 glClear(GL_COLOR_BUFFER_BIT); 142 //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound 143 ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData()); 144 SDL_GL_SwapWindow(window); 145 } 146 147 // Cleanup 148 ImGui_ImplOpenGL2_Shutdown(); 149 ImGui_ImplSDL2_Shutdown(); 150 ImGui::DestroyContext(); 151 152 SDL_GL_DeleteContext(gl_context); 153 SDL_DestroyWindow(window); 154 SDL_Quit(); 155 156 return 0; 157 }