[OSM-dev] strange OpenLayers longitude and latitude

[Vladimir Elistratov]

Hi!

I added the option to see the longitude and latitude for the TMS Layer 
http://tile.openstreetmap.org
It is well known line:
map.addControl(new OpenLayers.Control.MousePosition());

The longitude and latitude seem to be quite strange. Say, the 
longitude for London is around 90.

What is the problem about! How is it possible to get "normal" 
longitude and latitude?

I attach the small file for you to see how it happens.

The related Javascript code:
     <script type="text/javascript">
         var lon = 90;
         var lat = 29;
         var zoom = 6;
         var map, layer;

         function init(){
             map = new OpenLayers.Map( 'map', 
{maxResolution:1.40625/2} );

		var mapnik = new OpenLayers.Layer.TMS("Mapnik", 
"http://tile.openstreetmap.org/",
                                          { type: 'png', getURL: 
getTileURL, displayOutsideMaxExtent: true });

             map.addLayer(mapnik);

             map.addControl(new OpenLayers.Control.LayerSwitcher());
		map.addControl(new OpenLayers.Control.MousePosition());
             map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);
         }

	function getTileURL(bounds) {
		var res = this.map.getResolution();
		var x = Math.round((bounds.left - this.maxExtent.left) / (res * 
this.tileSize.w));
		var y = Math.round((this.maxExtent.top - bounds.top) / (res * 
this.tileSize.h));
    		var z = this.map.getZoom();
		var limit = Math.pow(2, z);

		if (y < 0 || y >= limit)
		{
			return OpenLayers.Util.getImagesLocation() + "404.png";
    		}
		else
		{
			x = ((x % limit) + limit) % limit;
			return this.url + z + "/" + x + "/" + y + "." + this.type;
		}
	}

     </script>

Thank you for any advice!

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