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Cesium-Prequel/Specs/Core/Simon1994PlanetaryPositions...

112 lines
4.5 KiB
JavaScript

import { defined } from "../../Source/Cesium.js";
import { JulianDate } from "../../Source/Cesium.js";
import { Math as CesiumMath } from "../../Source/Cesium.js";
import { Matrix3 } from "../../Source/Cesium.js";
import { Simon1994PlanetaryPositions as PlanetaryPositions } from "../../Source/Cesium.js";
import { TimeStandard } from "../../Source/Cesium.js";
import { Transforms } from "../../Source/Cesium.js";
describe("Core/Simon1994PlanetaryPositions", function () {
// Values for the X Y and Z were found using the STK Components GeometryTransformer on the position of the
// sun center of mass point and the earth J2000 reference frame.
it("computes correct sun position", function () {
var date = new JulianDate(2451545, 0, TimeStandard.TAI);
var sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
var X = 26500268539.790234;
var Y = -132756447253.27325;
var Z = -57556483362.533806;
expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON2);
expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON2);
expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON2);
date = new JulianDate(2456401.5, 0, TimeStandard.TAI);
sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
X = 131512388940.33589;
Y = 66661342667.949928;
Z = 28897975607.905258;
expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON3);
expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON3);
expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON3);
date = new JulianDate(2455998.591667, 0, TimeStandard.TAI);
sun = PlanetaryPositions.computeSunPositionInEarthInertialFrame(date);
X = 147109989956.19534;
Y = -19599996881.217579;
Z = -8497578102.7696457;
expect(X).toEqualEpsilon(sun.x, CesiumMath.EPSILON3);
expect(Y).toEqualEpsilon(sun.y, CesiumMath.EPSILON3);
expect(Z).toEqualEpsilon(sun.z, CesiumMath.EPSILON3);
});
// Values for X Y and Z were found using the STK Components GeometryTransformer on the Simon 1994 moon point and the earth
// J2000 reference frame.
it("computes correct moon position", function () {
var date = new JulianDate(2451545.0, 0, TimeStandard.TAI);
var moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
var X = -291632410.61232185;
var Y = -266522146.36821631;
var Z = -75994518.081043154;
expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);
date = new JulianDate(2456401.5, 0, TimeStandard.TAI);
moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
X = -223792974.4736526;
Y = 315772435.34490639;
Z = 97913011.236112773;
expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);
date = new JulianDate(2455998.591667, 0, TimeStandard.TAI);
moon = PlanetaryPositions.computeMoonPositionInEarthInertialFrame(date);
X = -268426117.00202647;
Y = -220468861.73998192;
Z = -110670164.58446842;
expect(X).toEqualEpsilon(moon.x, CesiumMath.EPSILON4);
expect(Y).toEqualEpsilon(moon.y, CesiumMath.EPSILON4);
expect(Z).toEqualEpsilon(moon.z, CesiumMath.EPSILON4);
});
it("has the sun rising in the east and setting in the west", function () {
//Julian dates for 24 hours, starting from July 6th 2011 @ 01:00 UTC
var transformMatrix = new Matrix3();
var timesOfDay = [];
var i;
for (i = 1; i < 25; i++) {
var date = new Date("July 6, 2011");
date.setUTCHours(i, 0, 0, 0);
timesOfDay.push(JulianDate.fromDate(date));
}
var angles = [];
for (i = 0; i < 24; i++) {
transformMatrix = Transforms.computeIcrfToFixedMatrix(
timesOfDay[i],
transformMatrix
);
if (!defined(transformMatrix)) {
transformMatrix = Transforms.computeTemeToPseudoFixedMatrix(
timesOfDay[i],
transformMatrix
);
}
var position = PlanetaryPositions.computeSunPositionInEarthInertialFrame(
timesOfDay[i]
);
Matrix3.multiplyByVector(transformMatrix, position, position);
angles.push(
CesiumMath.convertLongitudeRange(Math.atan2(position.y, position.x))
);
}
//Expect a clockwise motion.
for (i = 1; i < 24; i++) {
expect(angles[i]).toBeLessThan(angles[i - 1]);
}
});
it("works without a time", function () {
PlanetaryPositions.computeSunPositionInEarthInertialFrame(undefined);
});
});