Name modules more like their provide

src/ol/sphere.js

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+/**
+ * @license
+ * Latitude/longitude spherical geodesy formulae taken from
+ * http://www.movable-type.co.uk/scripts/latlong.html
+ * Licensed under CC-BY-3.0.
+ */
+
+goog.provide('ol.Sphere');
+
+goog.require('ol.math');
+
+
+/**
+ * @classdesc
+ * Class to create objects that can be used with {@link
+ * ol.geom.Polygon.circular}.
+ *
+ * For example to create a sphere whose radius is equal to the semi-major
+ * axis of the WGS84 ellipsoid:
+ *
+ * ```js
+ * var wgs84Sphere= new ol.Sphere(6378137);
+ * ```
+ *
+ * @constructor
+ * @param {number} radius Radius.
+ * @api
+ */
+ol.Sphere = function(radius) {
+
+  /**
+   * @type {number}
+   */
+  this.radius = radius;
+
+};
+
+
+/**
+ * Returns the geodesic area for a list of coordinates.
+ *
+ * [Reference](http://trs-new.jpl.nasa.gov/dspace/handle/2014/40409)
+ * Robert. G. Chamberlain and William H. Duquette, "Some Algorithms for
+ * Polygons on a Sphere", JPL Publication 07-03, Jet Propulsion
+ * Laboratory, Pasadena, CA, June 2007
+ *
+ * @param {Array.<ol.Coordinate>} coordinates List of coordinates of a linear
+ * ring. If the ring is oriented clockwise, the area will be positive,
+ * otherwise it will be negative.
+ * @return {number} Area.
+ * @api
+ */
+ol.Sphere.prototype.geodesicArea = function(coordinates) {
+  var area = 0, len = coordinates.length;
+  var x1 = coordinates[len - 1][0];
+  var y1 = coordinates[len - 1][1];
+  for (var i = 0; i < len; i++) {
+    var x2 = coordinates[i][0], y2 = coordinates[i][1];
+    area += ol.math.toRadians(x2 - x1) *
+        (2 + Math.sin(ol.math.toRadians(y1)) +
+        Math.sin(ol.math.toRadians(y2)));
+    x1 = x2;
+    y1 = y2;
+  }
+  return area * this.radius * this.radius / 2.0;
+};
+
+
+/**
+ * Returns the distance from c1 to c2 using the haversine formula.
+ *
+ * @param {ol.Coordinate} c1 Coordinate 1.
+ * @param {ol.Coordinate} c2 Coordinate 2.
+ * @return {number} Haversine distance.
+ * @api
+ */
+ol.Sphere.prototype.haversineDistance = function(c1, c2) {
+  var lat1 = ol.math.toRadians(c1[1]);
+  var lat2 = ol.math.toRadians(c2[1]);
+  var deltaLatBy2 = (lat2 - lat1) / 2;
+  var deltaLonBy2 = ol.math.toRadians(c2[0] - c1[0]) / 2;
+  var a = Math.sin(deltaLatBy2) * Math.sin(deltaLatBy2) +
+      Math.sin(deltaLonBy2) * Math.sin(deltaLonBy2) *
+      Math.cos(lat1) * Math.cos(lat2);
+  return 2 * this.radius * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+};
+
+
+/**
+ * Returns the coordinate at the given distance and bearing from `c1`.
+ *
+ * @param {ol.Coordinate} c1 The origin point (`[lon, lat]` in degrees).
+ * @param {number} distance The great-circle distance between the origin
+ *     point and the target point.
+ * @param {number} bearing The bearing (in radians).
+ * @return {ol.Coordinate} The target point.
+ */
+ol.Sphere.prototype.offset = function(c1, distance, bearing) {
+  var lat1 = ol.math.toRadians(c1[1]);
+  var lon1 = ol.math.toRadians(c1[0]);
+  var dByR = distance / this.radius;
+  var lat = Math.asin(
+      Math.sin(lat1) * Math.cos(dByR) +
+      Math.cos(lat1) * Math.sin(dByR) * Math.cos(bearing));
+  var lon = lon1 + Math.atan2(
+      Math.sin(bearing) * Math.sin(dByR) * Math.cos(lat1),
+      Math.cos(dByR) - Math.sin(lat1) * Math.sin(lat));
+  return [ol.math.toDegrees(lon), ol.math.toDegrees(lat)];
+};