private GameEngine(final JFrame frame) {
		this.frame = frame;
		// TODO: (maybe Windows specific problem): somehow the Canvas is 10
		// pixel to big. No idea why
		Dimension dim = new Dimension(Game.WIDTH - 10, Game.HEIGHT - 10);

		this.setPreferredSize(dim);
		this.setMinimumSize(dim);
		this.setMaximumSize(dim);

		addKeyListener(Controls.getInstance());
		setBackground(Color.DARK_GRAY);
	}