.. _program_listing_file_gui_Demeter_Renderer_SDL2.cpp:

Program Listing for File SDL2.cpp
=================================

|exhale_lsh| :ref:`Return to documentation for file <file_gui_Demeter_Renderer_SDL2.cpp>` (``gui/Demeter/Renderer/SDL2.cpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #include "imgui.h"
   #include "imgui_impl_opengl3.h"
   #include "imgui_impl_sdl2.h"
   
   #include "logging/Logger.hpp"
   
   #include "SDL2.hpp"
   
   bool SDL2::Init(size_t width, size_t height)
   {
     _width = width;
     _height = height;
   
     if (SDL_Init(SDL_INIT_VIDEO) < 0) {
       Log::failed << "SDL initialization failed! SDL_Error: " << GetError();
       return false;
     }
     _isSDLInit = true;
     SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
     SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
     SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
   
     _window = SDL_CreateWindow(
       "SDL2 OpenGL Cube",
       SDL_WINDOWPOS_CENTERED,
       SDL_WINDOWPOS_CENTERED,
       _width,
       _height,
       SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
     if (_window == nullptr) {
       Log::failed << "SDL_CreateWindow failed! SDL_Error: " << GetError();
       return false;
     }
   
     _context = SDL_GL_CreateContext(_window);
     if (_context == nullptr) {
       Log::failed << "SDL_GL_CreateContext failed! SDL_Error: " << GetError();
       return false;
     }
     glewExperimental = GL_TRUE;
     if (glewInit() != GLEW_OK) {
       Log::failed << "GLEW initialization failed!";
       return false;
     }
   
     // Initial viewport setup
     SetWindowSize(_width, _height);
   
     // Enable depth testing
     glEnable(GL_DEPTH_TEST);
     glDepthFunc(GL_LESS);
   
     // enable face culling, eg: triangles facing away from the camera
     glEnable(GL_CULL_FACE);
     glCullFace(GL_BACK);  // cull back-facing polygons
     glFrontFace(GL_CCW);  // winding order, eg: determines front-facing polygons
   
     // Enable alpha blending
     glEnable(GL_BLEND);
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
   
     if (IMG_Init(IMG_INIT_PNG | IMG_INIT_JPG) == 0) {
       Log::failed << "SDL_image initialization failed: " << GetIMGError();
       return false;
     }
     _isIMGInit = true;
   
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO &io = ImGui::GetIO();
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;
   
     ImGui_ImplSDL2_InitForOpenGL(_window, _context);
     ImGui_ImplOpenGL3_Init();
     return true;
   }
   
   SDL2::~SDL2()
   {
     if (ImGui::GetCurrentContext()) {
       ImGui_ImplOpenGL3_Shutdown();
       ImGui_ImplSDL2_Shutdown();
       ImGui::DestroyContext();
     }
   
     if (_isIMGInit)
       IMG_Quit();
     if (_context)
       SDL_GL_DeleteContext(_context);
     if (_window)
       SDL_DestroyWindow(_window);
     if (_isSDLInit)
       SDL_Quit();
   }