forked from: forked from: flash on 2010-3-7

/**
 * Copyright bradsedito ( http://wonderfl.net/user/bradsedito )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/aL6w
 */





package 
{
    import fl.transitions.easing.Back;
    import flash.display.Sprite;
    import flash.events.Event;

    public class Chain extends Sprite 
    {
        private var balls:Array;
        private var numBalls:Number = 5;
        private var spring:Number = 0.01;
        private var friction:Number = 0.5;
        private var gravity:Number = 0;
        
        public function Chain() 
        {
            init();
        }
        
        private function init():void 
        {
            
            balls = new Array();
            
            for (var i:uint = 0; i < numBalls; i++) 
            {
                var ball:Ball = new Ball(20,Math.random()*0xff0000);
                addChild(ball);
                balls.push(ball);
            }
            //ball0 = new Ball(10);
            //addChild(ball0);
            //ball1 = new Ball(20);
            //addChild(ball1);
            //ball2 = new Ball(25);
            //addChild(ball2);
            
            addEventListener(Event.ENTER_FRAME, onEnterFrame);
        }
        
        private function onEnterFrame(event:Event):void {
            //moveBall(ball0, mouseX, mouseY);
            //moveBall(ball1, ball0.x, ball0.y);
            //moveBall(ball2, ball1.x, ball1.y);
            graphics.clear();
            graphics.lineStyle(1);
            graphics.moveTo(mouseX, mouseY);
            moveBall(balls[0], mouseX, mouseY);
            graphics.lineTo(balls[0].x, balls[0].y);
            
            for (var i:uint = 1; i < numBalls; i++) {
                var ballA:Ball = balls[i - 1];
                var ballB:Ball = balls[i];
                moveBall(ballB, ballA.x, ballA.y);
                graphics.lineTo(ballB.x, ballB.y);
            }
            //graphics.lineTo(ball0.x, ball0.y);
            //graphics.lineTo(ball1.x, ball1.y);
            //graphics.lineTo(ball2.x, ball2.y);
        }
        private function moveBall(ball:Ball, targetX:Number, targetY:Number):void {
            ball.vx += (targetX - ball.x) * spring;
            ball.vy += (targetY - ball.y) * spring;
            ball.vy += gravity;
            ball.vx *= friction;
            ball.vy *= friction; 
            ball.x += ball.vx;
            ball.y += ball.vy;
        }
    }
}
import flash.display.Sprite;
     class Ball extends Sprite {
        public var radius:Number;
        public var color:uint;
        public var vx:Number = 0;
        public var vy:Number = 0;
            
        public function Ball(radius:Number = 40,color:uint=0xff0000 ):void {
            this.radius = radius;
            this.color = color;
            init();
        }
        public function init():void {
            graphics.beginFill(color);
            graphics.drawCircle(0, 0, radius);
            graphics.endFill();
        }
    }