As创建跟随鼠标指针的投影实现

import flash.filters.DropShadowFilter;
System.security.allowDomain("http://www.111cn.net");
var dropShadow:DropShadowFilter = new DropShadowFilter(4, 45, 0x000000, 0.8, 10, 10, 2, 2);
// 加载图像并在舞台上定位该图像。
var mclListener:Object = new Object();
mclListener.onLoadInit = function(target_mc:MovieClip):Void {
    target_mc._x = (Stage.width - target_mc._width) / 2;
    target_mc._y = (Stage.height - target_mc._height) / 2;
};
this.createEmptyMovieClip("img_mc", 10);
var img_mcl:MovieClipLoader = new MovieClipLoader();
img_mcl.addListener(mclListener);
img_mcl.loadClip("image1.jpg", img_mc);

// 当鼠标移动时，重新计算投影的位置。
var mouseListener:Object = new Object();
mouseListener.onMouseMove = function():Void {
    var p1:Number = img_mc._y - _ymouse;
    var p2:Number = img_mc._x - _xmouse;
    var degrees:Number = Math.atan2(p1, p2) / (Math.PI / 180);
    dropShadow.distance = Math.sqrt(Math.pow(p1, 2) + Math.pow(p2, 2)) * 0.5;
    dropShadow.blurX = dropShadow.distance;
    dropShadow.blurY = dropShadow.blurX;
    dropShadow.angle = degrees - 180;
    img_mc.filters = [dropShadow];
};
Mouse.addListener(mouseListener);