Lat/Long to x,y and x,y and Lat/Long

gistfile1.js

function Adjust(X,Y,x,y,z,w)
	{
		var offset=268435456; //(half of the earth circumference's in pixels at zoom level 21)
		var radius=offset/Math.PI;
		function LToX(x)
		{
			return Math.round(offset+radius*x*Math.PI/180);
		}
		function LToY(y)
		{
			return Math.round(offset-radius*Math.log((1+Math.sin(y*Math.PI/180))/(1-Math.sin(y*Math.PI/180)))/2);
		}
		function XToL(x)
		{
			return ((Math.round(x)-offset)/radius)*180/Math.PI;
		}
		function YToL(y)
		{
			return (Math.PI/2-2*Math.atan(Math.exp((Math.round(y)-offset)/radius)))*180/Math.PI;
		}
		if (w)
		{
			return {x:(LToX(X)-LToX(x))>>(21-z),y:(LToY(Y)-LToY(y))>>(21-z)};
		}
		else
		{
			return {x:XToL(LToX(x)+(X<<(21-z))),y:YToL(LToY(y)+(Y<<(21-z)))};
		}
	}//function Adjust
	function XYToLL(X,Y,x,y,z){return Adjust(X,Y,x,y,z,0)}
	//	X = X pixel offset of new map center from old map center
	//	Y = Y pixel offset of new map center from old map center
	//	x = Longitude of map center
	//	y = Latitude  of map center
	//	z = Zoom level
	//	result.x = Longitude of adjusted map center
	//	result.y = Latitude  of adjusted map center
	function LLToXY(X,Y,x,y,z){return Adjust(X,Y,x,y,z,1)}
	//	X = Longitude of marker center
	//	Y = Latitude  of marker center
	//	x = Longitude of map center
	//	y = Latitude  of map center
	//	z = Zoom level
	//	result.x = X pixel offset of marker center from map center
	//	result.y = Y pixel offset of marker center from map center
	function get_coordinates(event, show_coordinates_div_id){
                //make the array that the result will be held in
	        var array_result = new Array();
		//determine the x&y coordinates of the mouse cursor
		array_result['x'] = event.offsetX?(event.offsetX):event.pageX-document.getElementById('static_map_id').offsetLeft;
		array_result['y'] = event.offsetY?(event.offsetY):event.pageY-document.getElementById('static_map_id').offsetTop;
		//calulate the center values for the maps' x & y coordinates
		var old_map_center_x = 250;
		var old_map_center_y = 250;
	        //calculate the latitude and longitude
	        var result = XYToLL((array_result['x'] - old_map_center_x),(array_result['y'] - old_map_center_y),-88.1160419,42.9520781,17);
	        //save the longitude and latitude
	        array_result['longitude'] = result.x;
	        array_result['latitude'] = result.y;
	        //do we have the div id to update?
		if(show_coordinates_div_id){
	                //update the div
			document.getElementById(show_coordinates_div_id).innerHTML='x='+ array_result['x']+'|y='+array_result['y']+'|latitude='+array_result['latitude']+'|longitude='+array_result['longitude'];
		}//if
		return array_result;
	}//function get_coordinates()
        -->