package { import flash.display.Bitmap; import flash.display.BitmapData; import flash.display.PixelSnapping; import flash.display.Sprite; import flash.events.Event; import flash.events.MouseEvent; import flash.filters.BlurFilter; import flash.filters.GlowFilter; import flash.geom.ColorTransform; import flash.geom.Matrix; import flash.ui.Mouse; [SWF(width = "465", height = "465", frameRate = "60", backgroundColor=0x0)] public class Main extends Sprite { private var _bmpData:BitmapData; private var _bmp:Bitmap; private var _sp:Sprite; private var _color:int = 0xffffff; public function Main():void { if (stage) init(); else addEventListener(Event.ADDED_TO_STAGE, init); } private function init(e:Event = null):void { removeEventListener(Event.ADDED_TO_STAGE, init); // entry point _bmpData = new BitmapData(stage.stageWidth, stage.stageHeight, true, 0x00ffffff); _bmp = new Bitmap(_bmpData, PixelSnapping.AUTO, true); addChild(_bmp); _sp = new Sprite(); _sp.graphics.beginFill(_color); _sp.graphics.drawCircle(0, 0, 50); addChild(_sp); _sp.filters = [new GlowFilter(0x00ffff, 0.7, 10, 10, 100), new BlurFilter(50, 50)]; _sp.addEventListener(MouseEvent.MOUSE_MOVE, _drag); _sp.x = stage.stageWidth / 2; _sp.y = stage.stageHeight / 2; addEventListener(Event.ENTER_FRAME, _loop); } private function _drag(e:MouseEvent):void { e.target.startDrag(true); Mouse.hide(); } private function _loop(e:Event):void { _bmpData.colorTransform(_bmpData.rect, new ColorTransform(1, 1, 1, 1, 1, 1, 1, -10)); var mt:Matrix = new Matrix(); mt.translate(_sp.x, _sp.y); _bmpData.draw(_sp, mt); //ここの GlowFilter の _color を任意の数値にすることで残像の色が変わるよ _bmp.filters = [new GlowFilter(_color, 0.5), new BlurFilter(100, 100)]; _bmp.blendMode = "add"; } } }