var isDrag,LastX,LastY,LastLeft,LastTop;
 var hasTrack=false;
 
 function MapOnDown()
 {
   if(typeof(TrackLayer) == "undefined") return;
   isDrag=true;
   LastX=event.clientX;
   LastY=event.clientY;
   LastLeft=TrackLayer.offsetLeft;
   LastTop=TrackLayer.offsetTop;
 }

 function MapOnUp()
 {
	if(typeof(TrackLayer) == "undefined") return;
	isDrag=false;
    TrackLayer.style.top=document.getElementById("Map").style.top;
    TrackLayer.style.left=document.getElementById("Map").style.left;
 }
 
 function MapOnMove()
 {
    if(!isDrag) return
    var dx=event.clientX-LastX;
    var dy=event.clientY-LastY;
    TrackLayer.style.posLeft=LastLeft+dx;
    TrackLayer.style.posTop=LastTop+dy;
	//var mapImage=document.getElementById("MapControl1_Image");
    //TrackLayer.style.clip=mapImage.style.clip;    
 }