// Set minimum requirements for OpenGL
			SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
			SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
			SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
			SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 8);
			SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

			// Set video options to pass to SDL VIDEO subsystem.
			int iVideoFlags = SDL_OPENGL | SDL_HWPALETTE;
			if(Fullscreen) { iVideoFlags = SDL_OPENGL | SDL_HWPALETTE | SDL_FULLSCREEN; }

			std::cout << "Initializing OpenGL.. ";
			if(SDL_SetVideoMode(ScreenWidth, ScreenHeight, pVideoInfo->vfmt->BitsPerPixel, iVideoFlags))
			{
				std::cout << "OK.\n";

				// Set a black background.
				glClearColor(0.0f, 0.0f, 0.0f, 0);
			
				// ??????????????????
				glMatrixMode(GL_PROJECTION);
				glLoadIdentity();
			
				// Create an OpenGL Viewport in a 2d Plane
				glViewport(0, 0, ScreenWidth, ScreenHeight);
				glOrtho(0, ScreenWidth, ScreenHeight, 0, 0, 128);
			
				// ??????????????????
				glMatrixMode(GL_MODELVIEW);
				glLoadIdentity();
			
				// Enable 2D textures and configure some blending options.
				glEnable(GL_TEXTURE_2D);
				glEnable(GL_BLEND);
				glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
			}