public void init(GLAutoDrawable drawable) {
        //  
        // drawable.setGL(new DebugGL(drawable.getGL()));

        GL gl = drawable.getGL();

        //   
        gl.setSwapInterval(1);

        //     
        gl.glClearColor(0.5f, 0.5f, 0.5f, 0f);
        gl.glShadeModel(GL.GL_SMOOTH); // try setting this to GL_FLAT and see what happens.
        
        gl.glEnable(GL.GL_DEPTH_TEST);
        gl.glEnable(GL.GL_COLOR_MATERIAL);
        
        GameScene.init();
    }