マッハの卵でバウンス

/**
 * Copyright freddy ( http://wonderfl.net/user/freddy )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/qxKG
 */

// forked from freddy's マッハの卵
package {
    import flash.display.Shape;
    import flash.events.Event;
    import flash.display.Sprite;
    public class FlashTest extends Sprite {
        public function FlashTest() {
            // write as3 code here..
            function createEgg(rotV:int, x:int, st:int):Sprite {
                var sp:Sprite = new Sprite();
                sp.graphics.lineStyle(10);
                var h:int = 150;
                var w:int = 170;
                sp.graphics.drawEllipse(-w / 2, -h / 2, w, h);
                sp.x = x;
                sp.y = 200;
                var t:int = st;
                sp.addEventListener(Event.ENTER_FRAME, function (e:Event):void {
                  sp.rotation += rotV;
                  t++;
                  var r:int = 45;
                  var tt:int = t - int(t / r) * r;
                  var a:Number = (tt - r / 2);
                  
                  sp.y = a * a ;
                });
                return sp;
            }

            this.addChild(createEgg(10, 100, 0));
            this.addChild(createEgg(15, 300, 15));
            this.addChild(createEgg(20, 500, 30));
            this.scaleX = this.scaleY = 0.5;
            this.y = 100;
        }
    }
}