| 1 | // Dear ImGui: standalone example application for GLUT/FreeGLUT + OpenGL2, using legacy fixed pipeline |
| 2 | |
| 3 | // Learn about Dear ImGui: |
| 4 | // - FAQ https://dearimgui.com/faq |
| 5 | // - Getting Started https://dearimgui.com/getting-started |
| 6 | // - Documentation https://dearimgui.com/docs (same as your local docs/ folder). |
| 7 | // - Introduction, links and more at the top of imgui.cpp |
| 8 | |
| 9 | // !!! GLUT/FreeGLUT IS OBSOLETE PREHISTORIC SOFTWARE. Using GLUT is not recommended unless you really miss the 90's. !!! |
| 10 | // !!! If someone or something is teaching you GLUT today, you are being abused. Please show some resistance. !!! |
| 11 | // !!! Nowadays, prefer using GLFW or SDL instead! |
| 12 | |
| 13 | // On Windows, you can install Freeglut using vcpkg: |
| 14 | // git clone https://github.com/Microsoft/vcpkg |
| 15 | // cd vcpkg |
| 16 | // bootstrap - vcpkg.bat |
| 17 | // vcpkg install freeglut --triplet=x86-windows ; for win32 |
| 18 | // vcpkg install freeglut --triplet=x64-windows ; for win64 |
| 19 | // vcpkg integrate install ; register include and libs in Visual Studio |
| 20 | |
| 21 | #include "imgui.h" |
| 22 | #include "imgui_impl_glut.h" |
| 23 | #include "imgui_impl_opengl2.h" |
| 24 | #define GL_SILENCE_DEPRECATION |
| 25 | #ifdef __APPLE__ |
| 26 | #include <GLUT/glut.h> |
| 27 | #else |
| 28 | #include <GL/freeglut.h> |
| 29 | #endif |
| 30 | |
| 31 | #ifdef _MSC_VER |
| 32 | #pragma warning (disable: 4505) // unreferenced local function has been removed |
| 33 | #endif |
| 34 | |
| 35 | // Forward declarations of helper functions |
| 36 | void MainLoopStep(); |
| 37 | |
| 38 | // Our state |
| 39 | static bool show_demo_window = true; |
| 40 | static bool show_another_window = false; |
| 41 | static ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f); |
| 42 | |
| 43 | int main(int argc, char** argv) |
| 44 | { |
| 45 | // Create GLUT window |
| 46 | glutInit(&argc, argv); |
| 47 | #ifdef __FREEGLUT_EXT_H__ |
| 48 | glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_GLUTMAINLOOP_RETURNS); |
| 49 | #endif |
| 50 | glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_MULTISAMPLE); |
| 51 | glutInitWindowSize(1280, 800); |
| 52 | glutCreateWindow("Dear ImGui GLUT+OpenGL2 Example"); |
| 53 | |
| 54 | // Setup GLUT display function |
| 55 | // We will also call ImGui_ImplGLUT_InstallFuncs() to get all the other functions installed for us, |
| 56 | // otherwise it is possible to install our own functions and call the imgui_impl_glut.h functions ourselves. |
| 57 | glutDisplayFunc(MainLoopStep); |
| 58 | |
| 59 | // Setup Dear ImGui context |
| 60 | IMGUI_CHECKVERSION(); |
| 61 | ImGui::CreateContext(); |
| 62 | ImGuiIO& io = ImGui::GetIO(); (void)io; |
| 63 | io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable Keyboard Controls |
| 64 | io.ConfigFlags |= ImGuiConfigFlags_DockingEnable; // Enable Docking |
| 65 | |
| 66 | // Setup Dear ImGui style |
| 67 | ImGui::StyleColorsDark(); |
| 68 | //ImGui::StyleColorsLight(); |
| 69 | |
| 70 | // Setup Platform/Renderer backends |
| 71 | // FIXME: Consider reworking this example to install our own GLUT funcs + forward calls ImGui_ImplGLUT_XXX ones, instead of using ImGui_ImplGLUT_InstallFuncs(). |
| 72 | ImGui_ImplGLUT_Init(); |
| 73 | ImGui_ImplOpenGL2_Init(); |
| 74 | |
| 75 | // Install GLUT handlers (glutReshapeFunc(), glutMotionFunc(), glutPassiveMotionFunc(), glutMouseFunc(), glutKeyboardFunc() etc.) |
| 76 | // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs. |
| 77 | // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data. |
| 78 | // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data. |
| 79 | // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags. |
| 80 | ImGui_ImplGLUT_InstallFuncs(); |
| 81 | |
| 82 | // Load Fonts |
| 83 | // - If fonts are not explicitly loaded, Dear ImGui will select an embedded font: either AddFontDefaultVector() or AddFontDefaultBitmap(). |
| 84 | // This selection is based on (style.FontSizeBase * style.FontScaleMain * style.FontScaleDpi) reaching a small threshold. |
| 85 | // - You can load multiple fonts and use ImGui::PushFont()/PopFont() to select them. |
| 86 | // - If a file cannot be loaded, AddFont functions will return a nullptr. Please handle those errors in your code (e.g. use an assertion, display an error and quit). |
| 87 | // - Read 'docs/FONTS.md' for more instructions and details. |
| 88 | // - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to use FreeType for higher quality font rendering. |
| 89 | // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ ! |
| 90 | //style.FontSizeBase = 20.0f; |
| 91 | //io.Fonts->AddFontDefaultVector(); |
| 92 | //io.Fonts->AddFontDefaultBitmap(); |
| 93 | //io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\segoeui.ttf"); |
| 94 | //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf"); |
| 95 | //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf"); |
| 96 | //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf"); |
| 97 | //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf"); |
| 98 | //IM_ASSERT(font != nullptr); |
| 99 | |
| 100 | // Main loop |
| 101 | glutMainLoop(); |
| 102 | |
| 103 | // Cleanup |
| 104 | ImGui_ImplOpenGL2_Shutdown(); |
| 105 | ImGui_ImplGLUT_Shutdown(); |
| 106 | ImGui::DestroyContext(); |
| 107 | |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | void MainLoopStep() |
| 112 | { |
| 113 | // Start the Dear ImGui frame |
| 114 | ImGui_ImplOpenGL2_NewFrame(); |
| 115 | ImGui_ImplGLUT_NewFrame(); |
| 116 | ImGui::NewFrame(); |
| 117 | ImGuiIO& io = ImGui::GetIO(); |
| 118 | |
| 119 | // 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!). |
| 120 | if (show_demo_window) |
| 121 | ImGui::ShowDemoWindow(&show_demo_window); |
| 122 | |
| 123 | // 2. Show a simple window that we create ourselves. We use a Begin/End pair to create a named window. |
| 124 | { |
| 125 | static float f = 0.0f; |
| 126 | static int counter = 0; |
| 127 | |
| 128 | ImGui::Begin("Hello, world!"); // Create a window called "Hello, world!" and append into it. |
| 129 | |
| 130 | ImGui::Text("This is some useful text."); // Display some text (you can use a format strings too) |
| 131 | ImGui::Checkbox("Demo Window", &show_demo_window); // Edit bools storing our window open/close state |
| 132 | ImGui::Checkbox("Another Window", &show_another_window); |
| 133 | |
| 134 | ImGui::SliderFloat("float", &f, 0.0f, 1.0f); // Edit 1 float using a slider from 0.0f to 1.0f |
| 135 | ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color |
| 136 | |
| 137 | if (ImGui::Button("Button")) // Buttons return true when clicked (most widgets return true when edited/activated) |
| 138 | counter++; |
| 139 | ImGui::SameLine(); |
| 140 | ImGui::Text("counter = %d", counter); |
| 141 | |
| 142 | ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / io.Framerate, io.Framerate); |
| 143 | ImGui::End(); |
| 144 | } |
| 145 | |
| 146 | // 3. Show another simple window. |
| 147 | if (show_another_window) |
| 148 | { |
| 149 | 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) |
| 150 | ImGui::Text("Hello from another window!"); |
| 151 | if (ImGui::Button("Close Me")) |
| 152 | show_another_window = false; |
| 153 | ImGui::End(); |
| 154 | } |
| 155 | |
| 156 | // Rendering |
| 157 | ImGui::Render(); |
| 158 | glViewport(0, 0, (GLsizei)io.DisplaySize.x, (GLsizei)io.DisplaySize.y); |
| 159 | glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w); |
| 160 | glClear(GL_COLOR_BUFFER_BIT); |
| 161 | //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound, but prefer using the GL3+ code. |
| 162 | ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData()); |
| 163 | |
| 164 | glutSwapBuffers(); |
| 165 | glutPostRedisplay(); |
| 166 | } |