动画库tween.js var Tween = { Linear:function (start,alter,curTime,dur) {return start+curTime/dur*alter;},//最简单的线性变化,即匀速运动 Quad:{//二次方缓动 easeIn:function (start,alter,curTime,dur) { return start+Math.pow(curTime/dur,2)*alter; }, easeOut:function (start,al