openlayers/test/spec/ol/sphere/index.test.js

Build tools and sources for developing OpenLayers based mapping applications

// See http://www.movable-type.co.uk/scripts/latlong.html
// FIXME add tests for offset

goog.provide('ol.test.Sphere');

goog.require('ol.Sphere');
goog.require('ol.sphere.WGS84');
goog.require('ol.format.WKT');


describe('ol.Sphere', function() {

  var sphere = new ol.Sphere(6371);
  var expected = [{
    c1: [0, 0],
    c2: [0, 0],
    haversineDistance: 0
  }, {
    c1: [0, 0],
    c2: [45, 45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [0, 0],
    c2: [-45, 45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [0, 0],
    c2: [-45, -45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [0, 0],
    c2: [45, -45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [45, 45],
    c2: [45, 45],
    haversineDistance: 0
  }, {
    c1: [45, 45],
    c2: [-45, 45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [45, 45],
    c2: [-45, -45],
    haversineDistance: 13343.391197347048
  }, {
    c1: [45, 45],
    c2: [45, -45],
    haversineDistance: 10007.543398010286
  }, {
    c1: [-45, 45],
    c2: [-45, 45],
    haversineDistance: 0
  }, {
    c1: [-45, 45],
    c2: [-45, -45],
    haversineDistance: 10007.543398010286
  }, {
    c1: [-45, 45],
    c2: [45, -45],
    haversineDistance: 13343.391197347048
  }, {
    c1: [-45, -45],
    c2: [-45, -45],
    haversineDistance: 0
  }, {
    c1: [-45, -45],
    c2: [45, -45],
    haversineDistance: 6671.695598673525
  }, {
    c1: [45, -45],
    c2: [45, -45],
    haversineDistance: 0
  }];

  describe('haversineDistance', function() {

    it('results match Chris Veness\'s reference implementation', function() {
      var e, i;
      for (i = 0; i < expected.length; ++i) {
        e = expected[i];
        expect(sphere.haversineDistance(e.c1, e.c2)).to.roughlyEqual(
            e.haversineDistance, 1e-9);
      }
    });

  });

  describe('Vincenty area', function() {
    var geometry;
    before(function(done) {
      afterLoadText('spec/ol/format/wkt/illinois.wkt', function(wkt) {
        try {
          var format = new ol.format.WKT();
          geometry = format.readGeometry(wkt);
        } catch (e) {
          done(e);
        }
        done();
      });
    });

    it('results match the expected area of Ilinois', function() {
      var coords = geometry.getPolygon(0).getLinearRing(0).getCoordinates();
      expect(ol.sphere.WGS84.geodesicArea(coords)).to.equal(145978332359.37125);
    });
  });

});