Вращение круга мышью с регулируемой скоростью

[-De-]

package
{
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.geom.Matrix;
 
	public class Main extends Sprite
	{
		static public const STAGE_WIDTH:int = 800;
		static public const STAGE_HEIGHT:int = 600;
 
		private var $mover:Sprite;
		private var prevPhi:Number;
		private var $rotation:Number;
 
		public function Main() 
		{
			$mover = new Sprite();
 
			var mx:Matrix = new Matrix();
			mx.createGradientBox(STAGE_HEIGHT / 2, STAGE_HEIGHT / 2, Math.PI / 2);
			$mover.graphics.beginGradientFill('linear', [0xFF0000, 0x0000FF], [1, 1], [0, 255], mx);
			$mover.graphics.drawCircle(0, 0, STAGE_HEIGHT / 2);
			$mover.graphics.endFill();
 
			$mover.x = STAGE_WIDTH / 2;
			$mover.y = STAGE_HEIGHT / 2;
			this.addChild($mover);
 
			this.addEventListener(Event.ADDED_TO_STAGE, thisAddedToStageHandler);			
		}
 
		private function thisAddedToStageHandler(e:Event):void 
		{
			this.removeEventListener(Event.ADDED_TO_STAGE, thisAddedToStageHandler);
			stage.addEventListener(MouseEvent.MOUSE_DOWN, moverMouseDownHandler);
			stage.addEventListener(MouseEvent.MOUSE_UP, moverMouseUpHandler);
		}
 
		private function moverMouseDownHandler(e:MouseEvent):void 
		{
			prevPhi = Math.atan2(stage.mouseY - $mover.y, stage.mouseX - $mover.x);
			$rotation = $mover.rotation;
			$mover.addEventListener(MouseEvent.MOUSE_MOVE, moverMouseMoveHandler);
		}
 
		private function moverMouseUpHandler(e:MouseEvent):void 
		{
			$mover.removeEventListener(MouseEvent.MOUSE_MOVE, moverMouseMoveHandler);
		}
 
		private function moverMouseMoveHandler(e:MouseEvent):void 
		{
			const speed:Number = 0.3;
			var phi:Number = Math.atan2(stage.mouseY - $mover.y, stage.mouseX - $mover.x);
			var step:Number = phi - prevPhi;
			if (step > Math.PI)
				step -= 2 * Math.PI;
			else if (step < -Math.PI)
				step += 2 * Math.PI;
 
			//тут можно делать с шагом что угодно
			step *= speed;
 
			$rotation += step * 180 / Math.PI;
 
			prevPhi = phi;
 
			$mover.rotation = $rotation;
		}
 
	}
 
}