Egret的一些性能优化

/**
*<p> <code>Pool</code> 是对象池类，用于对象的存贮、重复使用。</p>
*<p>合理使用对象池，可以有效减少对象创建的开销，避免频繁的垃圾回收，从而优化游戏流畅度。</p>
*/
//class laya.utils.Pool
var Pool=(function(){
	function Pool(){}
	__class(Pool,‘laya.utils.Pool‘);
	Pool.getPoolBySign=function(sign){
		return Pool._poolDic[sign] || (Pool._poolDic[sign]=[]);
	}

	Pool.clearBySign=function(sign){
		if (Pool._poolDic[sign])Pool._poolDic[sign].length=0;
	}

	Pool.recover=function(sign,item){
		if (item["__InPool"])return;
		item["__InPool"]=true;
		Pool.getPoolBySign(sign).push(item);
	}

	Pool.getItemByClass=function(sign,cls){
		var pool=Pool.getPoolBySign(sign);
		var rst=pool.length ? pool.pop():new cls();
		rst["__InPool"]=false;
		return rst;
	}

	Pool.getItemByCreateFun=function(sign,createFun){
		var pool=Pool.getPoolBySign(sign);
		var rst=pool.length ? pool.pop():createFun();
		rst["__InPool"]=false;
		return rst;
	}

	Pool.getItem=function(sign){
		var pool=Pool.getPoolBySign(sign);
		var rst=pool.length ? pool.pop():null;
		if (rst){
			rst["__InPool"]=false;
		}
		return rst;
	}

	Pool._poolDic={};
	Pool.InPoolSign="__InPool";
	return Pool;
})()