Map Lat/Lon onto map pixels

gistfile1.js

/**
 * Convert Latitude and Longitude to CSS top and left positions for a map image.
 * Works with any map image that uses Spherical Mercator Projection (the same as Google Maps)
 * 
 * From http://stackoverflow.com/a/7021776/86780
 */
var latLonToTopLeft = function(lat, lon) {

	var imageNorthLat = 59.545457;  // Latitude of the image's northern edge
	var imageSouthLat = 49.431947;  // Latitude of the image's southern edge

	var imageWestLong = -11.140137; // Longitude of the image's western edge
	var imageEastLong = 2.757568;   // Longitude of the image's eastern edge

	var imageLongPixels = 1250;		// Width of the image in pixels
	var imageLatPixels = 1600;		// Height of the image in pixels

	var pixelsPerLat = imageLatPixels / (imageNorthLat - imageSouthLat);
	var pixelsPerLong = imageLongPixels / (imageEastLong - imageWestLong);

	var x = (lon-imageWestLong) * pixelsPerLong;
	var y = Math.abs(lat-imageNorthLat) * pixelsPerLat;

	return {
		'left' : x,
		'top' : y
	};

};