//Start a timer. Timer calls the timerHandler every 0.2 seconds.
var timer:Timer = new Timer(200, 0);
timer.addEventListener (TimerEvent.TIMER, timerHandler);
timer.start ();
 
//Get the center coordinates of the stage.
var centerX:Number = stage.stageWidth / 2;
var centerY:Number = stage.stageHeight / 2;
 
//This function is called by the timer.
function timerHandler (e:Event):void {
 
        //Create a new rectangle.
        var newRectangle:MyRectangle = new MyRectangle();
 
        //Set the position to same place as where the mouse cursor is.
        newRectangle.x = mouseX;
        newRectangle.y = mouseY;
 
        //Calculate x and y distances to the rectangle
        //from the center of the stage.
        var dx:Number = newRectangle.x - centerX;
        var dy:Number = newRectangle.y - centerY;
 
        //Calculate the distance to the rectangle from
        //the center of the stage (Pythagorean theorem)
        newRectangle.radius = Math.sqrt(dx*dx + dy*dy);
 
        //Calculate the angle of the rectangle from the center
        newRectangle.myAngle = Math.atan2(dy, dx);
 
        //Set the angle speed (how fast we rotate)
        newRectangle.speed = 0.06;
 
        //At first,set the rectangle to be invisible
        newRectangle.alpha = 0;
 
        //Assign a random scale to the rectangle
        newRectangle.scaleX = Math.random() + 1.5;
        newRectangle.scaleY = newRectangle.scaleX;
 
        // Get access to the ColorTransform instance associated with the rectangle.
        var colorInfo:ColorTransform = newRectangle.transform.colorTransform;
 
        // Set a random color for the ColorTransform object.
        colorInfo.color = 0xffffff * Math.random();
 
        //Apply the random color for the rectangle
        newRectangle.transform.colorTransform = colorInfo;
 
        //Add the rectangle to the stage
        addChild (newRectangle);
 
        //Add ENTER_FRAME to animate the rotation
        newRectangle.addEventListener (Event.ENTER_FRAME, moveRectangle);
}
 
//This function rotates a rectangle
function moveRectangle (e:Event):void {
 
        //Get the rectangle from the event target
        var rectangle:MovieClip = e.target as MovieClip;
 
        //Calculate the new x and y positions for the rectangle
        var newX:Number = centerX + Math.cos(rectangle.myAngle) * rectangle.radius;
        var newY:Number = centerY + Math.sin(rectangle.myAngle) * rectangle.radius;
 
        //Increase the angle for the next frame
        rectangle.myAngle += rectangle.speed;
 
        //Assign the new position
        rectangle.x = newX;
        rectangle.y = newY;
 
        //Decreate the radius to get a "spiral" animation
        rectangle.radius -= 0.6;
 
        //Reduce the scale 
        rectangle.scaleX -= rectangle.radius * 0.0001;
        rectangle.scaleY -= rectangle.radius * 0.0001;
 
        //Increase the alpha if it's not one and radius is larger than 50
        if (rectangle.alpha < 1 && rectangle.radius > 50) {
                rectangle.alpha += 0.05;
        }
        //Start decreasing alpha if radius is smaller than 50
        if (rectangle.radius < 50) {
                rectangle.alpha -= 0.005;
        }
 
        //If radius is smaller than zero, remove the rectangle
        if (rectangle.radius < 0) {
                rectangle.removeEventListener (Event.ENTER_FRAME, moveRectangle);
                removeChild (rectangle);
        }
}