SlashC++Programmer

package
{
    import flash.display.Shape;
    import flash.display.Sprite;
    import flash.events.Event;

    /**
     * ...
     * @author SlashC++Programmer
     */
    public class Main extends Sprite
    {
        private var dx:Number;
        private var dy:Number;

        private static var screenWidth:Number = 800;
        private static var screenHeight:Number = 600;

        public function Main()
        {
            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
        }

        public function init(e:Event = null):void
        {
            removeEventListener(Event.ADDED_TO_STAGE, init);

            // make square
            var square:Shape = new Shape();
            square.graphics.beginFill(0xff0000, 1);
            square.graphics.drawRect(0, 0, 64, 64);
            square.graphics.endFill();
            addChild(square);

            square.x = 40;
            square.y = 40;
            dx = 2;
            dy = 2;

            //timebase values
            var passed:Number = 0;
            var now:Number = 0;
            var accumulator:Number = 0;
            var dt:Number = 1000 / 60;
            var frameRate:Number = 60 / 1000;
            var last:Number = new Date().getTime();


            addEventListener(Event.ENTER_FRAME, GameLoop);

            function GameLoop(e:Event):void
            {
                now = new Date().getTime();
                passed = now - last;
                last = now;

                accumulator += passed;


                while (accumulator >= dt)
                {
                    Update(dt);
                    accumulator -= dt;
                }
            }

            function Update(deltaTime:Number):void
            {
                square.x += dx * deltaTime * frameRate;
                square.y += dy * deltaTime * frameRate;

                if (square.x <= 0 ||  square.x >= screenWidth - square.width)
                {
                    dx = -dx;
                }

                if (square.y <= 0 ||  square.y >= screenHeight - square.height)
                {
                    dy = -dy;
                }
            }

        }
    }
}