public void update(Graphics g) {
if (offScreenImage == null) offScreenImage = this.createImage(GAME_WIDTH, GAME_HEIGHT);
Graphics gOffScreenImage = offScreenImage.getGraphics();
Color c = gOffScreenImage.getColor();
gOffScreenImage.setColor(BACKGROUND_COLOR);
gOffScreenImage.fillRect(0, 0, GAME_WIDTH, GAME_HEIGHT);
gOffScreenImage.setColor(c);
paint(gOffScreenImage);
g.drawImage(offScreenImage, 0, 0, null);
}
