// Convert tile coordinate from GoogleMaps to scheme from MSR MapCruncher
//function CustomGetTileUrl(a,b) {
function ConvertToQuad(a,b) {
	z = b;
	var quad = "";
	for (var i = z; i > 0; i--){
	    var mask = 1 << (i - 1);
	    var cell = 0;
	    if ((a.x & mask) != 0)
	       cell++;
	    if ((a.y & mask) != 0)
	       cell += 2;
	    quad += cell;
	}
	return quad;
}