title: Change scenes in game openGL
body: <p>i'm continue my dialog with openGL and c++ and for a now i want to make "scenes", that will change each other. for example screen with button "go next", i push button and then begin game.
  What is the best approach with openGL in c++ for this ? The main question is what make with glut initialization commands like :</p>
  
  <pre><code>glutInit(&amp;argc, argv);
  glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB);
  glutInitWindowSize(screenWidth, screenHeight);
  glutInitWindowPosition(0,0);
  glutCreateWindow("Puzzle quest!");
  
  // Registration
  glutDisplayFunc(Draw);
  glutIdleFunc(Draw);
  </code></pre>
  
  <p>Is i need to implement this method in both classes, or only in one, and then only "show start button/ hide game functionality, hide start button/ show game functionality+start timer" ?</p>