var brOK=false;
var mie=false;
var aver=parseInt(navigator.appVersion.substring(0,1));
var aname=navigator.appName;

var dPixl;
if (window.screen.width==800){
	dPixl=100;
} else {
	dPixl=50;
}

function checkbrOK()
{if(aname.indexOf("Internet Explorer")!=-1)
   {if(aver>=4) brOK=navigator.javaEnabled();
    mie=true;
   }
 if(aname.indexOf("Netscape")!=-1)  
   {if(aver>=4) brOK=navigator.javaEnabled();}
}


var vmin=2;
var vmax=5;
var vr=1;
var timer1;

function Chip(chipname,width,height,left,top)
{this.named=chipname;
 this.vx=vmin+vmax*Math.random();
 this.vy=vmin+vmax*Math.random();
 this.w=width;
 this.h=height;
 this.xx=0+left;
 this.yy=0+top;
 this.timer1=null;
}

function movechip(chipname)
{
 if(brOK)
  {eval("chip="+chipname);
   if(!mie)
    {pageX=window.pageXOffset;
     pageW=window.innerWidth;
     pageY=window.pageYOffset;
     pageH=window.innerHeight;
    }
   else
    {pageX=window.document.body.scrollLeft;
     pageW=window.document.body.offsetWidth-177;
     pageY=window.document.body.scrollTop;
     pageH=window.document.body.offsetHeight-193;
    } 

   chip.xx=chip.xx+chip.vx;
   chip.yy=chip.yy+chip.vy;
   
   chip.vx+=vr*(Math.random()-0.5);
   chip.vy+=vr*(Math.random()-0.5);
   if(chip.vx>(vmax+vmin))  chip.vx=(vmax+vmin)*2-chip.vx;
   if(chip.vx<(-vmax-vmin)) chip.vx=(-vmax-vmin)*2-chip.vx;
   if(chip.vy>(vmax+vmin))  chip.vy=(vmax+vmin)*2-chip.vy;
   if(chip.vy<(-vmax-vmin)) chip.vy=(-vmax-vmin)*2-chip.vy;

   if(chip.xx<=pageX)
     {chip.xx=pageX;
      chip.vx=vmin+vmax*Math.random();
     }
   if(chip.xx>=pageX+pageW-chip.w-dPixl)
     {chip.xx=pageX+pageW-chip.w-dPixl;
      chip.vx=-vmin-vmax*Math.random();
     }

   pageY=140; //³õʼ¾à¶¥µÄ¸ß

   if(chip.yy<=pageY)
     {chip.yy=pageY;
      chip.vy=vmin+vmax*Math.random();
     }
   if(chip.yy>=pageY+pageH-chip.h)
     {chip.yy=pageY+pageH-chip.h;
      chip.vy=-vmin-vmax*Math.random();
     }

   if(!mie)
      {eval('document.'+chip.named+'.top ='+chip.yy);
       eval('document.'+chip.named+'.left='+chip.xx);
      } 
   else
      {eval('document.all.'+chip.named+'.style.pixelLeft='+chip.xx);
       eval('document.all.'+chip.named+'.style.pixelTop ='+chip.yy); 
      }
   chip.timer1=setTimeout("movechip('"+chip.named+"')",200);
  }
}