terriajs/test/Map/EarthGravityModel1996Spec.js

Geospatial data visualization platform.

'use strict';

/*global require,describe,xdescribe,it,expect,beforeAll*/
var Cartographic = require('terriajs-cesium/Source/Core/Cartographic');
var EarthGravityModel1996 = require('../../lib/Map/EarthGravityModel1996');

var describeIfSupported = EarthGravityModel1996.isSupported() ? describe : xdescribe;

describeIfSupported('EarthGravityModel1996', function() {
    var egm96;

    beforeAll(function() {
        egm96 = new EarthGravityModel1996(require('file-loader!../../wwwroot/data/WW15MGH.DAC'));
    });

    // NGA calculator is here: http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm96/intpt.html

    it('produces a single result consistent with NGA calculator', function(done) {
        egm96.getHeight(0.0, 0.0).then(function(height) {
            expect(height).toBe(17.16);
            done();
        });
    });

    it('produces multiple results consistent with NGA calculator', function(done) {
        var testData = [
            // longitude, latitude, expected height
            0.0, 89.74, 13.92,
            180.0, 89.74, 13.49,
            -180.0, 89.74, 13.49,
            0.0, -89.74, -29.55,
            180.0, -89.74, -30.11,
            -180.0, -89.74, -30.11,
            0.15, 0.0, 17.12,
            -0.15, 0.0, 17.17
        ];

        var cartographics = [];
        var i;

        for (i = 0; i < testData.length; i += 3) {
            cartographics.push(Cartographic.fromDegrees(testData[i], testData[i + 1], 0.0));
        }

        egm96.getHeights(cartographics).then(function() {
            for (var i = 0; i < cartographics.length; ++i) {
                expect(Math.abs(cartographics[i].height - testData[i * 3 + 2])).toBeLessThan(0.01);
            }
            done();
        });
    });

    it('works at the north pole', function(done) {
        egm96.getHeight(0.0, Math.PI).then(function(height) {
            expect(height).toBe(13.61);
            done();
        });
    });

    it('works at the south pole', function(done) {
        egm96.getHeight(0.0, -Math.PI).then(function(height) {
            expect(height).toBe(-29.53);
            done();
        });
    });
});