ballgrav

/**
 * Copyright bradsedito ( http://wonderfl.net/user/bradsedito )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/qXo1
 */

// forked from honekingu's 宿題：自由落下。
package {
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.text.TextField;
    public class FlashTest extends Sprite {
        private var ball:Sprite
        private var a:Number//加速
        private var ao:Number//1フレーム毎の加速度
        private var v:Number//速度
        private var speed:TextField = new TextField()
        public function FlashTest() {
            // write as3 code here..
            ball = new Sprite()
            ball.graphics.beginFill(0xFFFFFF * Math.random())
            ball.graphics.drawCircle(0,0,16);
            ball.graphics.endFill();
            ball.y=0
            ball.x=Math.random()*433+16
            v = 0//初速度
            a = 5.0//加速度
            ao = a/30        
            addChild(ball)
            addEventListener(Event.ENTER_FRAME,freefall)
            addChild(speed)
        }
        public function freefall(event:Event):void{
            if(ball.y+ball.height/2>stage.stageHeight){
                ball.y=stage.stageHeight-ball.height/2;
                v=-v;
            }
            if(ball.y<-8){
                ball.graphics.clear();
                ball.graphics.beginFill(0xFFFFFF * Math.random())
                ball.graphics.drawCircle(0,0,16);
                ball.graphics.endFill();
            }

            ball.y += v
            v += ao
            speed.text = "Speed:"+Math.floor(v)
        }

    }
}