earth radius: change leaflet and leaflet-draw to use the radius value…

… used by the s2 geometry library

this library is used in the ingress backend, so distance calculation, etc are far closer if we use the value from that

external/L.Geodesic.js

@@ -40,7 +40,7 @@ Modified by qnstie 2013-07-17 to maintain compatibility with Leaflet.draw
   // to calculate intermediate points. hopeefully this will avoid the rounding issues seen in the full intermediate
   // points code that have been seen
   function geodesicConvertLine(startLatLng, endLatLng, convertedPoints) {
-    var R = 6378137; // earth radius in meters (doesn't have to be exact)
+    var R = 6367000.0; // earth radius in meters (doesn't have to be exact)
     var d2r = Math.PI/180.0;
     var r2d = 180.0/Math.PI;
 
@@ -179,7 +179,7 @@ Modified by qnstie 2013-07-17 to maintain compatibility with Leaflet.draw
 
 
     _calcPoints: function() {
-      var R = 6378137; //earth radius in meters (approx - taken from leaflet source code)
+      var R = 6367000.0; //earth radius in meters (approx - taken from leaflet source code)
       var d2r = Math.PI/180.0;
       var r2d = 180.0/Math.PI;
 //console.log("geodesicCircle: radius = "+this._mRadius+"m, centre "+this._latlng.lat+","+this._latlng.lng);

external/leaflet-src.js

@@ -1191,7 +1191,7 @@ L.LatLng.prototype = {
 	distanceTo: function (other) { // (LatLng) -> Number
 		other = L.latLng(other);
 
-		var R = 6378137, // earth radius in meters
+		var R = 6367000.0, // earth radius in meters
 		    d2r = L.LatLng.DEG_TO_RAD,
 		    dLat = (other.lat - this.lat) * d2r,
 		    dLon = (other.lng - this.lng) * d2r,
@@ -1512,7 +1512,7 @@ L.CRS.EPSG3857 = L.extend({}, L.CRS, {
 
 	project: function (latlng) { // (LatLng) -> Point
 		var projectedPoint = this.projection.project(latlng),
-		    earthRadius = 6378137;
+		    earthRadius = 6367000.0;
 		return projectedPoint.multiplyBy(earthRadius);
 	}
 });
@@ -8299,7 +8299,7 @@ L.Control.Scale = L.Control.extend({
 	_update: function () {
 		var bounds = this._map.getBounds(),
 		    centerLat = bounds.getCenter().lat,
-		    halfWorldMeters = 6378137 * Math.PI * Math.cos(centerLat * Math.PI / 180),
+		    halfWorldMeters = 6367000.0 * Math.PI * Math.cos(centerLat * Math.PI / 180),
 		    dist = halfWorldMeters * (bounds.getNorthEast().lng - bounds.getSouthWest().lng) / 180,
 
 		    size = this._map.getSize(),

external/leaflet.draw.js

@@ -1602,7 +1602,7 @@ L.GeometryUtil = {
 				area += ((p2.lng - p1.lng) * d2r) *
 						(2 + Math.sin(p1.lat * d2r) + Math.sin(p2.lat * d2r));
 			}
-			area = area * 6378137.0 * 6378137.0 / 2.0;
+			area = area * 6367000.0 * 6367000.0 / 2.0;
 		}
 
 		return Math.abs(area);