旋转的箭头

我们想让一个影片剪辑或 Sprite 影片通过旋转来指向鼠标的位置，这将是个挑战。旋转(rotation)将成为我们工具箱中非常的工具，可以应用于游戏制作，鼠标追踪，界面设计等。

package
{
	import flash.display.Sprite;
	
	public class away3DDemo extends Sprite
	{
		private var arrow:Arrow;
		
		public function away3DDemo()
		{
			arrow = new Arrow(this);
		}
	}
}

package
{
	import flash.display.Sprite;
	import flash.events.Event;
	public class Arrow extends Sprite
	{
		private var _parent:*
		private var arrow:ArrowMc;
		public function Arrow(p:*)
		{
			_parent = p;
			_parent.addChild(this);
			init();
		}
		private function init():void{
			arrow = new  ArrowMc();
			arrow.x = _parent.stage.stageWidth/2;
			arrow.y = _parent.stage.stageHeight/2;
			this.addChild(arrow);
			this.addEventListener(Event.ENTER_FRAME,onEnterFrame);
		}
		public function onEnterFrame(event:Event):void{
			var dx:Number = this.mouseX - arrow.x;
			var dy:Number = this.mouseY - arrow.y;
			var radians:Number = Math.atan2(dy,dx);
			arrow.rotation = radians * 180/Math.PI;
		}
	}
}
import flash.display.Sprite;
class ArrowMc extends Sprite{
	public function ArrowMc(){
		init();
	}
	private function init():void{
		graphics.lineStyle(1,0,1);
		graphics.beginFill(0xffff00); 
		graphics.moveTo(-50,-25); 
		graphics.lineTo(0,-25); 
		graphics.lineTo(0,-50);
		graphics.lineTo(50,0);
		graphics.lineTo(0,50);
		graphics.lineTo(0,25); 
		graphics.lineTo(-50,25); 
		graphics.lineTo(-50,-25); 
		graphics.endFill();
	}
}