imnodes_glfw.cpp

// Dear ImGui: standalone example application for GLFW + OpenGL 3, using
// programmable pipeline (GLFW is a cross-platform general purpose library for
// handling windows, inputs, OpenGL/Vulkan/Metal graphics context creation,
// etc.) If you are new to Dear ImGui, read documentation from the docs/ folder
// + read the top of imgui.cpp. Read online:
// https://github.com/ocornut/imgui/tree/master/docs

#include "example/node_editor.h"
#include "imgui.h"
#include "imgui_impl_glfw.h"
#include "imgui_impl_opengl3.h"
#include "imnodes.h"
#include <GLFW/glfw3.h> // Will drag system OpenGL headers
#include <stdio.h>

// [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, char **) {
  // 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

  // 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

  ImNodes::CreateContext();
  example::NodeEditorInitialize();

  // 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, or clear/overwrite your copy of the mouse data.
    // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input
    // data to your main application, or clear/overwrite your copy of the
    // keyboard data. 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)
      example::NodeEditorShow();

    // 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();
  example::NodeEditorShutdown();
  ImNodes::DestroyContext();
  ImGui::DestroyContext();

  glfwDestroyWindow(window);
  glfwTerminate();

  return 0;
}