/*
		Map controls functions for IE
		*/
		function ZoomMap(nNewAlt,nImgCaller,sImgPath)
		{
			/*
			Zoom map to an absolute altitude in Km
			*/
			var sMapUrl, sSubstr, sNewstr;
			var nStart, nEnd;
					
			for (i = 1; i <= 9; i++)
				 document.images["mapZoom_" + i].src = sImgPath + "Everyday/mapControls/mapZoom-level-dn.gif";
			
			document.images["mapZoom_" + nImgCaller].src = sImgPath + "Everyday/mapControls/mapZoom-level-up.gif";
			
			sMapUrl = new String(document.images.imgMap.src);
			
			nStart = new Number(sMapUrl.indexOf("&z="));
			nEnd   = new Number(sMapUrl.indexOf("&",nStart +1));
			
			if (nStart == -1 || nEnd == -1)
				return;
			
			sSubstr = new String(sMapUrl.slice(nStart,nEnd));			
			sNewstr = new String("&z=" + nNewAlt);
			sMapUrl = sMapUrl.replace(sSubstr,sNewstr);

			nStart = new Number(sMapUrl.indexOf("?a="));
			nEnd   = new Number(sMapUrl.indexOf("&"));
			
			if (nStart == -1 || nEnd == -1)
				return;
			
			sSubstr = new String(sMapUrl.slice(nStart,nEnd));			
			sMapUrl = sMapUrl.replace(sSubstr,"?a=1");

					
			document.images.imgMap.src = sMapUrl;
		}
		
		function AdjustZoom(nToAdjust,sImgPath)
		{
			/*
			Adjust map zoom by a relative value
			*/
			var nZoomLevel = new Number(0);
			var nAdjust = new Number(nToAdjust);
			var rgLevels = Array(320,160,80,40,20,10,5,3,1);
			for (i = 1; i <= 9; i++)
			{	
				 if (document.images["mapZoom_" + i].src == sImgPath + "Everyday/mapControls/mapZoom-level-up.gif")
				 {
					nZoomLevel = (i + nAdjust);
					break;
				 }
			}	 
			
			if (nZoomLevel <= 0 || nZoomLevel > 9) 
				return;
			else
				ZoomMap(rgLevels[nZoomLevel-1],nZoomLevel,sImgPath);			
		}