Canvas Animation Kit实验......如何清除画布？

我可以制作一个obj使用画布绘制如下:

MyObj.myDiv = new Canvas($("effectDiv"), Setting.width,  Setting.height);

然后,我使用它在画布上绘制一个矩形:

    var c =  new Rectangle(80, 80,
        {
            fill: [220, 40, 90]
        }
    );
    var move = new Timeline;
    move.addKeyframe(0,
        {
            x: 0,
            y: 0
        }
    );
    c.addTimeline(move);
    MyObj.myDiv.append(c);

但是在绘制矩形后,我想要清除画布,但我不知道哪种方法以及如何做到这一点......

O ...还有一件事:它是CAKE的网站: 链接

清除画布:

canvas.clear = true; // makes the canvas clear itself on every frame
canvas.fill = somecolor; // fills the canvas with some color on every frame
// with canvas.clear = false and low-opacity fill, fancy motion blur effect

Removing the rectangle from the canvas:
rectangle.removeSelf();
or
canvas.removeChild(rectangle);