😏★,°:.☆(￣▽￣)/$:.°★ 😏
这篇文章主要介绍ImGui图形用户界面库配置与使用。
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文章目录
- :smirk:1. 项目介绍
- :blush:2. 环境配置
- :satisfied:3. 使用说明
😏1. 项目介绍
项目Github地址：https://github.com/ocornut/imgui
Dear ImGui (ImGui) 是一个开源的、用 C++ 编写的图形用户界面（GUI）库。它由OCornut创建，旨在为应用程序和工具提供创建用户界面的简单高效的方式。
以下是 Dear ImGui 的一些主要特性和特点：
1.即时模式 GUI：ImGui 遵循即时模式 GUI 的范例，用户界面不是通过保留模式或对象层次结构构建的。相反，每一帧都需要重新创建和绘制用户界面。这种设计使得创建和更新界面变得非常灵活和直观。
2.轻量级和可嵌入性：ImGui 是一个轻量级库，只有几个文件组成，可轻松嵌入到现有项目中。它没有任何外部依赖，使得集成和部署变得非常简单。
3.跨平台支持：ImGui 可以在多个平台上运行，包括 Windows、MacOS、Linux 和其他一些操作系统。它提供了与底层图形 API（如OpenGL、DirectX）的集成，以便在不同平台上绘制用户界面。
4.简单易用的 API：ImGui 提供了一个简单直观的 API，使得创建用户界面变得非常容易。您可以使用各种控件（如按钮、文本框、滑块等）来构建界面，并通过监听用户输入和响应事件来实现交互。
5.自定义性强：ImGui 具有强大的自定义能力，您可以自定义主题、样式和控件外观以满足您的需求。此外，您还可以编写自定义的渲染器，以实现与不同图形 API 的集成。
Dear ImGui 是一个简单、灵活且强大的 GUI 库，适用于各种应用程序和工具的用户界面开发。无论是创建原型、调试工具还是构建实际应用程序，它都提供了一套方便的工具和框架来简化界面开发过程。
😊2. 环境配置
下面进行环境配置：
# windows vs # windows端需要预装directx，VS的Kit中默认会有 # 源码中的example下有示例VS工程(.sln)，下载源码后直接用VS打开运行
# windows clion # CMakeLists.txt示例，提前装好了glfw+glad+freeglut+opencv cmake_minimum_required(VERSION 3.19) project(opengl_demo) set(CMAKE_CXX_STANDARD 14) include_directories("./env/include") link_directories("./env/lib") include_directories("./env/imgui") include_directories("./env/imgui/backends") set(OpenCV_DIR "D:/develop/opencv341_mingw/x64/mingw/lib") find_package(OpenCV 3 REQUIRED) MESSAGE("OpenCV version : ${OpenCV_VERSION}") include_directories(${OpenCV_INCLUDE_DIRS}) link_directories(${OpenCV_LIBRARIES}) # ${OpenCV_LIB_DIR} file(GLOB IMGUI "./env/imgui/*.cpp") # 1.80 add_executable(opengl_demo main.cpp env/glad.c ${IMGUI}) target_link_libraries(opengl_demo glfw3 # 3.3.9 opengl32 freeglut # 3.4.0 glu32 ${OpenCV_LIBRARIES} xinput )# ubuntu cmake sudo apt install libglfw3 libglfw3-dev # 安装glfw # 一个博主已经写了一个基于cmake的示例，这里引用一下 http://t.csdnimg.cn/LDY5H https://github.com/tashaxing/imgui_cmake_starter # 包含了imgui 1.83的源码和示例程序，直接编译即可
😆3. 使用说明
运行示例：
windows VS直接生成运行即可，ubuntu下cmake编译指令如下：
mkdir build && cd build cmake .. make ./imgui_cmake_starter
Imgui的示例代码：
#include "imgui.h" #include "imgui_impl_glfw.h" #include "imgui_impl_opengl3.h" #include
#if defined(IMGUI_IMPL_OPENGL_ES2) #include // 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. #elif 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() #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD2) #include // Initialize with gladLoadGL(...) or gladLoaderLoadGL() #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING2) #define GLFW_INCLUDE_NONE // GLFW including OpenGL headers causes ambiguity or multiple definition errors. #include // Initialize with glbinding::Binding::initialize() #include using namespace gl; #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING3) #define GLFW_INCLUDE_NONE // GLFW including OpenGL headers causes ambiguity or multiple definition errors. #include // Initialize with glbinding::initialize() #include using namespace gl; #else #include IMGUI_IMPL_OPENGL_LOADER_CUSTOM #endif // Include glfw3.h after our OpenGL definitions #include // [Win32] Our example includes a copy of glfw3.lib pre-compiled with VS2010 to maximize ease of testing and compatibility with old VS compilers. // To link with VS2010-era libraries, VS2015+ requires linking with legacy_stdio_definitions.lib, which we do using this pragma. // Your own project should not be affected, as you are likely to link with a newer binary of GLFW that is adequate for your version of Visual Studio. #if defined(_MSC_VER) && (_MSC_VER >= 1900) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS) #pragma comment(lib, "legacy_stdio_definitions") #endif static void glfw_error_callback(int error, const char* description) { fprintf(stderr, "Glfw Error %d: %s\n", error, description); } int main(int argc, char** argv) { // Setup window glfwSetErrorCallback(glfw_error_callback); if (!glfwInit()) return 1; // Decide GL+GLSL versions #if defined(IMGUI_IMPL_OPENGL_ES2) // GL ES 2.0 + GLSL 100 const char* glsl_version = "#version 100"; glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0); glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_ES_API); #elif defined(__APPLE__) // GL 3.2 + GLSL 150 const char* glsl_version = "#version 150"; glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // 3.2+ only glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // Required on Mac #else // GL 3.0 + GLSL 130 const char* glsl_version = "#version 130"; glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0); //glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // 3.2+ only //glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // 3.0+ only #endif // Create window with graphics context GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+OpenGL3 example", NULL, NULL); if (window == NULL) return 1; glfwMakeContextCurrent(window); glfwSwapInterval(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; #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD2) bool err = gladLoadGL(glfwGetProcAddress) == 0; // glad2 recommend using the windowing library loader instead of the (optionally) bundled one. #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING2) bool err = false; glbinding::Binding::initialize(); #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING3) bool err = false; glbinding::initialize([](const char* name) { return (glbinding::ProcAddress)glfwGetProcAddress(name); }); #else bool err = false; // If you use IMGUI_IMPL_OPENGL_LOADER_CUSTOM, your loader is likely to requires some form of initialization. #endif if (err) { fprintf(stderr, "Failed to initialize OpenGL loader!\n"); return 1; } // Setup Dear ImGui context IMGUI_CHECKVERSION(); ImGui::CreateContext(); ImGuiIO& io = ImGui::GetIO(); (void)io; //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable Keyboard Controls //io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad; // Enable Gamepad Controls // Setup Dear ImGui style ImGui::StyleColorsDark(); //ImGui::StyleColorsClassic(); // Setup Platform/Renderer backends ImGui_ImplGlfw_InitForOpenGL(window, true); ImGui_ImplOpenGL3_Init(glsl_version); // 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 'docs/FONTS.md' 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); // Our state bool show_demo_window = true; bool show_another_window = false; ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f); // Main loop while (!glfwWindowShouldClose(window)) { // 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. glfwPollEvents(); // Start the Dear ImGui frame ImGui_ImplOpenGL3_NewFrame(); ImGui_ImplGlfw_NewFrame(); 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(); int display_w, display_h; glfwGetFramebufferSize(window, &display_w, &display_h); glViewport(0, 0, display_w, display_h); glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w); glClear(GL_COLOR_BUFFER_BIT); ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData()); glfwSwapBuffers(window); } // Cleanup ImGui_ImplOpenGL3_Shutdown(); ImGui_ImplGlfw_Shutdown(); ImGui::DestroyContext(); glfwDestroyWindow(window); glfwTerminate(); return 0; } 以上。