图片填充圆

package {
	import flash.display.Sprite;
	import flash.geom.Matrix;
	import flash.display.Loader;
	import flash.net.URLRequest;
	import flash.display.BitmapData;
	import flash.events.Event;
	public class Drawing extends Sprite {
		private var _loader:Loader;
		public function Drawing(   ) {
			_loader = new Loader(   );
			_loader.load(new URLRequest("image.jpg"));
			_loader.contentLoaderInfo.addEventListener
(Event.COMPLETE, onImageLoad);
		}
		private function onImageLoad(event:Event):void {
			var bitmap:BitmapData = new BitmapData
(_loader.width, _loader.height);
			bitmap.draw(_loader, new Matrix(   ));
			var matrix:Matrix = new Matrix(   );
			matrix.scale(.1, .1);
			var sampleSprite:Sprite = new Sprite(   );
			sampleSprite.graphics.lineStyle(   );
			sampleSprite.graphics.beginBitmapFill(bitmap, matrix);
			sampleSprite.graphics.drawCircle(100, 100, 100);
			sampleSprite.graphics.endFill(   );
			addChild(sampleSprite);
		}
	}
}