// javascript document
var xpos = 0; //初始左边距
var ypos = 0; //初始上边距
var step = 1;
var delay = 10; //移动速度,越小越快
var f_height = 0;
var hoffset = 0;
var woffset = 0;
var yon = 0;
var xon = 0;
var pause = true;
var interval;
var img1=document.getelementbyid("ad1");//id
img1.style.top = ypos;

function changepos()
{
 f_width = document.documentelement.clientwidth;
 f_height = document.documentelement.clientheight;

 hoffset = img1.offsetheight;
 woffset = img1.offsetwidth;
 img1.style.left = xpos + document.documentelement.scrollleft+"px";
 img1.style.top = ypos + document.documentelement.scrolltop+"px";
 if (yon)
  {ypos = ypos + step;}
 else
  {ypos = ypos - step;}
 if (ypos < 0)
  {yon = 1;ypos = 0;}
 if (ypos >= (f_height - hoffset))
  {yon = 0;ypos = (f_height - hoffset);}
if(ypos > (f_height - hoffset-document.getelementbyid("gb").offsetheight*3) && xpos < (f_width - woffset - document.getelementbyid("gb").offsetwidth*3)){
	 document.getelementbyid("gb").style.right = -document.getelementbyid("gb").offsetwidth+"px";document.getelementbyid("gb").style.top = 0;
}else if(ypos < (f_height - hoffset-document.getelementbyid("gb").offsetheight*3) && xpos > (f_width - woffset - document.getelementbyid("gb").offsetwidth*3)){
	 document.getelementbyid("gb").style.right = woffset+"px";document.getelementbyid("gb").style.top = hoffset - document.getelementbyid("gb").offsetheight+"px";}
else if(ypos > (f_height - hoffset-document.getelementbyid("gb").offsetheight*3) && xpos > (f_width - woffset - document.getelementbyid("gb").offsetwidth*3)){
	 document.getelementbyid("gb").style.right = woffset+"px";document.getelementbyid("gb").style.top = 0;}
 else if(ypos < (f_height - hoffset-document.getelementbyid("gb").offsetheight*3) && xpos < (f_width - woffset - document.getelementbyid("gb").offsetwidth*3)){
	 document.getelementbyid("gb").style.top = hoffset+"px";document.getelementbyid("gb").style.right = 0;}
 if (xon)
  {xpos = xpos + step;}
 else
  {xpos = xpos - step;}
 if (xpos < 0)
  {xon = 1;xpos = 0;}
 if (xpos >= (f_width - woffset))
  {xon = 0;xpos = (f_width - woffset);   }
 }

 function start()
  {
   img1.visibility = "visible";
  interval = setinterval('changepos()', delay);
 }
 
 function pause_resume()
 {
  if(pause)
  {
   clearinterval(interval);
   pause = false;}
  else
  {
   interval = setinterval('changepos()',delay);
   pause = true;
   }
  }
 start();
 function imgtz(x){
	 clearinterval(interval);
}
function imgks(x){
 interval = setinterval('changepos()',delay);
}
function close_left1(){
    ad1.style.visibility='hidden';
}