export var Earth = Util.extend({}, CRS, {
  wrapLng: [-180, 180],
  R: 6371000,
  distance: function (latlng1, latlng2) {
    var rad = Math.PI / 180,
      lat1 = latlng1.lat * rad,
      lat2 = latlng2.lat * rad,
      sinDLat = Math.sin(((latlng2.lat - latlng1.lat) * rad) / 2),
      sinDLon = Math.sin(((latlng2.lng - latlng1.lng) * rad) / 2),
      a =
        sinDLat * sinDLat + Math.cos(lat1) * Math.cos(lat2) * sinDLon * sinDLon,
      c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    return this.R * c;
  },
});