同步，异步，阻塞，非阻塞

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var Item=Class.create(),
Carousel=Class.create();
Item.prototype={
init:function(parent,radians,imgOptions){
var elem=document.createElement("div");
this.element=elem;
this.radians=radians;
this.parent=parent;
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elem.onmouseup=bind(this,function(){
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update:function(deltaRadians){
this.radians=(this.radians+deltaRadians+2*Math.PI)%(Math.PI*2);
var opt=this.parent.options,
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center=opt.center,
itemSize=opt.itemSize,
_left=radius[0]*Math.cos(this.radians),
_top=radius[1]*Math.sin(this.radians),
zRadius=this.parent.zoomAxis?radius[1]:radius[0],//select out the short base radius
zFactor=this.parent.zoomAxis?_top:_left, //
zoom=(zFactor+zRadius*1.5)/(2.5*zRadius),
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Carousel.prototype={
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this.rotate( len );
this.isClick();
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pre:function(){
var len = this.items.length == 0 ? 0 : -2*Math.PI/this.items.length;
this.rotate(len);
this.isClick();
},
init:function(){
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var arg=arguments[0],
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radius;
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this.items=[];
this.timer=null;
this.flag=false;
this.setConfig(arg.configs||{});
radius=this.options.radius;
this.zoomAxis=Math.abs(radius[0])>Math.abs(radius[1]);//选短轴，即true时选y,false选x
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},
setConfig:function(opts){
this.options={
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duration:1000,
center:[this.element.offsetWidth/2,this.element.offsetHeight/2],// x,y
radius:[200,50], // x,y
itemSize:[200,120], //width,height
radiusX:200,
radiusY:50,
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easy:function(p){
return 1-Math.pow(1-p,3);
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rotate:function(radians){
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clearInterval(this.timer);
this.begin=(new Date()).getTime();
this.rotateRadians=radians;
this.completeFraction=0;
this.timer=setInterval(bind(this,function(){this.update();}),this.options.interval);
},
update:function(){
var opt=this.options,
_this=this,
fraction,
rad
now=(new Date()).getTime();
if((this.begin+opt.duration)<=now){
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this.flag=false;
rad=(1-this.completeFraction)*this.rotateRadians;
each(this.items,function(val,key){
val.update(rad);
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else{
fraction=opt.easy((now-this.begin)/opt.duration);
rad=this.rotateRadians*(fraction-this.completeFraction);
this.completeFraction=fraction;
each(this.items,function(val,key){
val.update(rad);
});
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this.isClick();

},
isClick:function(){
each(this.items,function(val,key){
var o = val.element;
var is_click = ( o.style.zIndex > 98 ) ? true : false;
o.onclick=function(){
return is_click;
}
});
}
}
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<div class="carousel pa" id="con">
<script type="text/javascript" >
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,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic2.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic3.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic4.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic5.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic6.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic7.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic8.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic9.jpg" alt="" /></a></div>'
,'<div class="list"><a target="_blank" href="#" title="" target="_blank"><img src="http://topic.aili.com/images/topic_digital_lephone01/pic10.jpg" alt="" /></a></div>'
]
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</div>

本文出自 “糖糖阁” 博客，请务必保留此出处http://lovesnow.blog.51cto.com/8334309/1358412