[GIS] Get distance in meters between lat/lng coordinates, divided in North and East direction

Question

I've got 2 couples of lat/lng coordinates and I would like to get distance between them in meters, but divided in X (east) and Y (north) directions.

I've found this function in a Stack Overflow answer to get distance between 2 points, but I don't know how to separate the North and the East distance:

var rad = function(x) {
  return x * Math.PI / 180;
};

var getDistance = function(p1, p2) {
  var R = 6378137; // Earth’s mean radius in meter
  var dLat = rad(p2.lat() - p1.lat());
  var dLong = rad(p2.lng() - p1.lng());
  var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
    Math.cos(rad(p1.lat())) * Math.cos(rad(p2.lat())) *
    Math.sin(dLong / 2) * Math.sin(dLong / 2);
  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  var d = R * c;
  return d; // returns the distance in meter
}; 

Answer 1

I've found the solution. Here is a javascript function to get the distance divided in east and nord gap:

var getDistance = function(p1, p2) {
    var R = 6371e3; // metres
    var φ1 = rad(p1.lat());
    var φ2 = rad(p2.lat());
    var λ1 = rad(p1.lng());
    var λ2 = rad(p2.lng());

    var x = Math.round((λ2-λ1) * Math.cos((φ1+φ2)/2)*R);
    var y = Math.round((φ2-φ1)*R);

    return {est: x, nord: y};
};