public void TestIntercept() { double myMass = 10000; double parentMass = 1.989e30; //solar mass. Game game = new Game(); EntityManager mgr = new EntityManager(game, false); BaseDataBlob[] parentblobs = new BaseDataBlob[3]; parentblobs[0] = new PositionDB(mgr.ManagerGuid) { X_AU = 0, Y_AU = 0, Z_AU = 0 }; parentblobs[1] = new MassVolumeDB() { Mass = parentMass }; parentblobs[2] = new OrbitDB(); Entity parentEntity = new Entity(mgr, parentblobs); Vector3 currentPos_m = new Vector3 { X = Distance.AuToMt(-0.77473184638034), Y = Distance.AuToMt(0.967145228951685) }; Vector3 currentVelocity_m = new Vector3 { Y = Distance.KmToM(40) }; double nonNewtSpeed_m = Distance.KmToM(283.018); Vector3 targetObjPosition = new Vector3 { X = Distance.AuToMt(0.149246434443459), Y = Distance.AuToMt(-0.712107888348067) }; Vector3 targetObjVelocity = new Vector3 { Y = Distance.KmToM(35) }; double sgp_m = OrbitMath.CalculateStandardGravityParameterInM3S2(myMass, parentMass); //KeplerElements ke = OrbitMath.KeplerFromVelocityAndPosition(sgp, targetObjPosition, targetObjVelocity); var currentDateTime = new DateTime(2000, 1, 1); OrbitDB targetOrbit = OrbitDB.FromVector(parentEntity, myMass, parentMass, sgp_m, targetObjPosition, targetObjVelocity, currentDateTime); var intercept_m = OrbitMath.GetInterceptPosition_m(currentPos_m, nonNewtSpeed_m, targetOrbit, currentDateTime); var futurePos1_m = OrbitProcessor.GetAbsolutePosition_m(targetOrbit, intercept_m.Item2); var futurePos2_m = intercept_m.Item1; Assert.AreEqual(futurePos1_m.Length(), futurePos2_m.Length(), 0.01); Assert.AreEqual(futurePos1_m.X, futurePos2_m.X, 0.01); Assert.AreEqual(futurePos1_m.Y, futurePos2_m.Y, 0.01); Assert.AreEqual(futurePos1_m.Z, futurePos2_m.Z, 0.01); var time = intercept_m.Item2 - currentDateTime; var distance_m = (currentPos_m - intercept_m.Item1).Length(); var speed = distance_m / time.TotalSeconds; var distb_m = nonNewtSpeed_m * time.TotalSeconds; var timeb = distance_m / nonNewtSpeed_m; Assert.AreEqual(nonNewtSpeed_m, speed, 1.0e-4); var dif = distance_m - distb_m; Assert.AreEqual(distance_m, distb_m, 100.0, "Out by a difference of " + dif + " meters"); }