// Computes the amount of latitude degrees for a given distance in pixel at a given zoom level. private static double deltaLat(double deltaPixel, double lat, sbyte zoom, int tileSize) { long mapSize = MercatorProjection.getMapSize(zoom, tileSize); double pixelY = MercatorProjection.latitudeToPixelY(lat, mapSize); double lat2 = MercatorProjection.pixelYToLatitude(pixelY + deltaPixel, mapSize); return(Math.Abs(lat2 - lat)); }