[ActionScript 3.0] AS3 绘制星形

package
{
    import flash.display.Sprite;
    import flash.events.Event;
    
    /**
     * @author Frost.Yen
     * @E-mail 871979853@qq.com
     * @create 2015-9-9 下午4:47:50
     *
     */
    [SWF(width="1024",height="1024",frameRate="3")]
    public class DrawStar extends Sprite
    {
        public function DrawStar()
        {
            initViews();
            initEventListeners();
        }
        private function initViews():void
        {
            draw();
        }
        private function initEventListeners():void
        {
            this.addEventListener(Event.ENTER_FRAME,onFresh);
        }
        private function onFresh(e:Event):void
        {
            this.removeChildren();
            draw();
        }
        private function draw():void
        {
            for(var i:int=0;i<64;i++){
                var star:Star = new Star(Math.random()*10+2,50,20,Math.random()*255-Math.random()*0xffffff,Math.random()*0xffffff-Math.random()*255,true);
                star.x = i%8*100+100;
                star.y = Math.floor(i/8)*100+100;
                this.addChild(star);
            }
        }
    }
}
import flash.display.Sprite;

class Star extends Sprite
{
    private var _b:Boolean;
    private var _x:Number;
    private var _y:Number;
    /**
     * 
     * @param    len 星形边数
     * @param    radius1 五角星中心点离较远顶点的距离（可看作五角星外接圆的半径）
     * @param    radius2 五角星中心点离较近顶点的距离（可看作五角星内接圆的半径）
     * @param    lineColor 线条颜色
     * @param    fillColor 填充颜色
     * @param    isFill 是否填充
     */
    public function Star(len:int=5,radius1:Number=50,radius2:Number=20,lineColor:uint=0xff0000,fillColor:uint=0x00ffff,isFill:Boolean=false){
        if(len<=1){
            trace("星形边数至少为2");
            return;
        }
        this.graphics.lineStyle(1,lineColor);
        if(isFill){
            this.graphics.beginFill(fillColor)
        }
        this.graphics.moveTo(radius2,0);
        for(var i:int = 1;i<=len*2;i++){
            _b?[_x=radius2*Math.cos(i*Math.PI*2/(len*2)),_y=radius2*Math.sin(i*Math.PI*2/(len*2))]:[_x=radius1*Math.cos(i*Math.PI*2/(len*2)),_y=radius1*Math.sin(i*Math.PI*2/(len*2))];
            this.graphics.lineTo(_x,_y);
            _b=!_b;
        }
        if(len%2!=0){
            this.rotation = 90;
        }
    }
}