package {
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.ui.Mouse;
    import flash.ui.MouseCursor;
     
    public class Spring3 extends Sprite {
        private var ball:Ball;
        private var spring:Number=0.1;
        private var vx:Number=0;
        private var vy:Number=0;
        private var friction:Number=0.95;
         
         
        public function Spring3() {
            init();
        }
        private function init():void {
            ball = new Ball(10);
            addChild(ball);
            addEventListener(Event.ENTER_FRAME, onEnterFrame);
            Mouse.cursor = MouseCursor.HAND;
        }
        private function onEnterFrame(event:Event):void {
            var dx:Number = mouseX-ball.x;
            var dy:Number = mouseY-ball.y;
            var ax:Number = dx*spring;
            var ay:Number = dy*spring;
            vx+=ax;
            vy+=ay;
             
            vx*=friction;
            vy*=friction;
            ball.x+=vx;
            ball.y+=vy;
            graphics.clear();
            graphics.lineStyle(1);          
            graphics.moveTo(mouseX, mouseY);
            graphics.lineTo(ball.x, ball.y);
        }
    }
}