gistfile1.cpp

//
// Run the game loop
//
void Engine::Run(){
    Loop();
}


//========= Privates ==========//

//
// Initializes all the required SDL modules.
//
void Engine::InitSDL(){
    //Start SDL
    if (SDL_Init( SDL_INIT_EVERYTHING )  != 0){
        cerr << "SDL_Init() Failed: " <<
        SDL_GetError() << endl;
        exit(1);
    }
    
    // Initialize SDL_ttf library
    if (TTF_Init() != 0) {
        cerr << "TTF_Init() Failed: " << TTF_GetError() << endl;
        SDL_Quit();
        exit(1);
    }
    SDL_CreateWindowAndRenderer(res_width_, res_height_, SDL_WINDOW_OPENGL, &window_, &renderer_);
    SDL_SetRenderDrawColor(renderer_, 0, 0, 0, 255);
    
    screen_surface_ = SDL_CreateRGBSurface(0, res_width_, res_height_, 32,
                                   0x00FF0000,
                                   0x0000FF00,
                                   0x000000FF,
                                   0xFF000000);
    
    if (!screen_surface_) {
        cerr << "SDL_CreateRGBSurface failed: " << SDL_GetError() << endl;
        SDL_Quit();
        exit(1);
    }
    
    screen_texture_ = SDL_CreateTexture(renderer_,
                                        SDL_PIXELFORMAT_ARGB8888,
                                        SDL_TEXTUREACCESS_STREAMING,
                                        res_width_, res_height_);
}

void Engine::InitOpenGL()
{
    glDisable(GL_LIGHTING);
    glDisable(GL_TEXTURE_2D);
    
    glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );
    
    glViewport( 0, 0, res_width_, res_height_ );
    
    glClear( GL_COLOR_BUFFER_BIT );
    
    glMatrixMode( GL_PROJECTION );
    glLoadIdentity();
    
    glOrtho(0.0f, res_width_, res_height_, 0.0f, -1.0f, 1.0f);
    
    glMatrixMode( GL_MODELVIEW );
    glLoadIdentity();
}

//
// The main game loop
//
void Engine::Loop(){
    
    double real_fps;
    int frame_start, frame_end;
    
    running_ = true;
    while (running_) {
        real_fps = 1000.0 / (SDL_GetTicks() - frame_start);
        frame_start = SDL_GetTicks();
        
        Update();
        Display();
        
        // Schedule next frame
        frame_end = SDL_GetTicks();
        printf("%d ms\n", (frame_end - frame_start));
        SDL_Delay( std::max(0, int(frame_start + (1000.0 / target_fps_) - frame_end )));
    }
}

//
// Render
//
void Engine::Display(){
    SDL_Surface* frame_surface = ConvertToSDLSurface(flow_.frame());
    
    SDL_BlitScaled(frame_surface, NULL, screen_surface_, NULL);
    SDL_FreeSurface(frame_surface);
    
    // Push to texture and render
    SDL_UpdateTexture(screen_texture_, NULL, screen_surface_->pixels, screen_surface_->pitch);
    SDL_RenderClear(renderer_);
    SDL_RenderCopy(renderer_, screen_texture_, NULL, NULL);
    
    glLoadIdentity();
    glDisable(GL_TEXTURE_2D);
    glColor3f(1.0, 1.0, 1.0);
    glBegin( GL_QUADS );
      glVertex3f( 10.0f, 50.0f, 0.0f ); /* Top Left */
      glVertex3f( 50.0f, 50.0f, 0.0f ); /* Top Right */
      glVertex3f( 50.0f, 10.0f, 0.0f ); /* Bottom Right */
      glVertex3f( 10.0f, 10.0f, 0.0f ); /* Bottom Left */
    glEnd( );

    glColor3f(1.0, 1.0, 1.0);
    SDL_RenderPresent(renderer_);
}