扇形排列图片算法

Question

把图片排列成如图样式，图片数量不固定，图片大小固定，求算法，谢谢

rotation已能算出，就是y的大小不知道怎么算出来

for(var i:int = 0; i < length; i++){
img = new Image();
img.source = "card/bg.png";
img.smoothBitmapContent = true;
img.x = i * 20;
r0 = -(length - (i * 2));
img.rotation=r0;
cbox.addElement(img);
}

Answer 1

貌似用Flex的，我用按钮代替图片写了个Demo
[code="java"]<?xml version="1.0"?>
layout="absolute"
creationComplete="init()">
mx:Script
<![CDATA[
import mx.controls.Button;

        private var buttonList:Array;
        private static const buttonNum:int=20;
        private static const oPoint:Point=new Point(500, 900);
        private static const startAngle:Number=-125;
        private static const paddingAngle:Number=3;
        private static const radius:Number=800;

        private function init():void
        {
            buttonList=new Array();
            var b:Button;
            for (var i:int=0; i < buttonNum; i++)
            {
                b=new Button();
                b.toolTip="Hi" + i.toString();
                b.width=100;
                b.height=200;
                buttonList.push(b);
                this.addChild(b);

                var p:Point=new Point(oPoint.x + radius * Math.cos((startAngle + i * paddingAngle) * Math.PI / 180), oPoint.y + radius * Math.sin((startAngle + i * paddingAngle) * Math.PI / 180));
                b.x=p.x;
                b.y=p.y;
                b.rotation=90 + (startAngle + i * paddingAngle);
            }
        }
    ]]>
</mx:Script>

/mx:Application[/code]