var cCurImg = "";
function imgroll(cImg,nID,nTotal)
 {
  if (cCurImg!=cImg)
  {
  for (var i=1; i<=nTotal; i++)
	{
	var cImgLoop = "img"+i;
	var cHTML = document.getElementById(cImgLoop).outerHTML;
	if (cHTML.indexOf('_roll.png')>-1)
		document.getElementById(cImgLoop).outerHTML=cHTML.replace('_roll.png','.png');
	}
   }
   var cHTML = document.getElementById(cImg).outerHTML
   if ( (nID==1) && (cHTML.indexOf('_roll')==-1) )
   {
	document.getElementById(cImg).outerHTML=cHTML.replace('.png','_roll.png');
        cCurImg = cImg;
   }
   if ( (nID==2) && (cHTML.indexOf('_roll')>-1) )
   {
	document.getElementById(cImg).outerHTML=cHTML.replace('_roll.png','.png');
        cCurImg = "";
   }
 }