图标滑动放大效果

(function($){
 $.fn.bubbleup = function(settings){
  settings=$.extend({
   tooltip: false,//是否提示文本
   scale:120,//放大后的图片宽度
   fontFamily:'Helvetica, Arial, sans-serif',//提示文本字体
   color:'#333333',//提示文本字体颜色
   fontSize:12,//提示文本字体大小
   fontWeight:'bold',//提示文本字体粗细
   inSpeed:'fast',//鼠标划过放大时的速度
   outSpeed:'fast'//鼠标已出缩小时时的速度
   },settings);
   return this.each(function(){
    $.fn.bubbleup.runing( $( this ), settings );
   })
 };
 $.fn.bubbleup.runing=function($this,settings){
  var smallImgW=$this.width();
  $this.mouseover(function(){
   if (settings.tooltip) {
    tip=$('<div>' + $(this).attr('alt') + '</div>').css({
     fontFamily: settings.fontFamily,
     color: settings.color,
     fontSize: settings.fontSize,
     fontWeight: settings.fontWeight,
     position: 'absolute',
     zIndex: 100000
    }).remove().css({top:0,left: 0,visibility:'hidden',display:'block'}).appendTo(document.body);
    var position=$.extend({},$this.offset(),{width:this.offsetWidth,height:this.offsetHeight});
    var tipWidth = tip[0].offsetWidth;
    var tipHeight = tip[0].offsetHeight;
    tip.stop().css({
      top: position.top - tipHeight,
      left: position.left + position.width / 2 - tipWidth / 2,
      visibility: 'visible'
     }).animate({top:'-='+(settings.scale/2-smallImgW/2)},settings.inSpeed);
   }
   $this.closest('li').css({'z-index':100000});
   $this.stop().css({'z-index':100000,'top':0,'left':0,'width':smallImgW}).animate({
    left:-settings.scale/2+smallImgW/2,
    top:-settings.scale/2+smallImgW/2,
    width:settings.scale
   },settings.inSpeed)
  }).mouseout(function(){
   $this.closest('li').css({'z-index':100});
   $this.closest('li').next().css({'z-index':0});
   $this.closest('li').next().css({'z-index':0});
   $this.closest('li').next().children('img').css({'z-index':0});
   if(settings.tooltip){tip.remove()}
   $this.stop().animate({left:0,top:0,width:smallImgW},settings.outSpeed,function(){
    $this.css({'z-index':0});
   });
  });
  
 }
})(jQuery);