@override
  Future<void> onLoad() async {
    final parallax = await loadParallaxComponent(
      [
        ParallaxImageData('stars_0.png'),
        ParallaxImageData('stars_1.png'),
        ParallaxImageData('stars_2.png'),
      ],
      baseVelocity: Vector2(0, -5), //基本的速度，向下
      repeat: ImageRepeat.repeat,
      velocityMultiplierDelta: Vector2(0, 5),//不同的图片，速度不一样
    );
    add(parallax);
    }