public void GetItmCoordinates_ShouldConvertToNorthEast()
{
var northEast = new NorthEast { North = 3, East = 4 };
var converter = Substitute.For<ICoordinatesConverter>();
converter.Wgs84ToItm(Arg.Any<LatLon>()).Returns(northEast);
_itmGridController = new ItmGridController(converter);
var response = _itmGridController.GetItmCoordinates(1, 2);
Assert.AreEqual(northEast.North, response.North);
Assert.AreEqual(northEast.East, response.East);
}
/// <summary>
/// Local Grid to Lat/Lon conversion
/// </summary>
/// <param name="northEast"></param>
/// <param name="from"></param>
/// <param name="to"></param>
/// <returns></returns>
private LatLon Grid2LatLon(NorthEast northEast, string from, string to)
{
double y = northEast.North + Grids[from].FalseNorthing;
double x = northEast.East - Grids[from].FalseEasting;
double M = y / Grids[from].ScaleFactor;
double a = Datums[to].EquatorialEarthRadius;
double b = Datums[to].PolarEarthRadius;
double e = Datums[to].Eccentricity;
double esq = Datums[to].EccentricitySquared;
double mu = M / (a * (1 - e * e / 4 - 3 * Math.Pow(e, 4) / 64 - 5 * Math.Pow(e, 6) / 256));
double ee = Math.Sqrt(1 - esq);
double e1 = (1 - ee) / (1 + ee);
double j1 = 3 * e1 / 2 - 27 * e1 * e1 * e1 / 32;
double j2 = 21 * e1 * e1 / 16 - 55 * e1 * e1 * e1 * e1 / 32;
double j3 = 151 * e1 * e1 * e1 / 96;
double j4 = 1097 * e1 * e1 * e1 * e1 / 512;
// Footprint Latitude
double fp = mu + j1 * Math.Sin(2 * mu) + j2 * Math.Sin(4 * mu) + j3 * Math.Sin(6 * mu) + j4 * Math.Sin(8 * mu);
double sinfp = Math.Sin(fp);
double cosfp = Math.Cos(fp);
double tanfp = sinfp / cosfp;
double eg = (e * a / b);
double eg2 = eg * eg;
double C1 = eg2 * cosfp * cosfp;
double T1 = tanfp * tanfp;
double R1 = a * (1 - e * e) / Math.Pow(1 - (e * sinfp) * (e * sinfp), 1.5);
double N1 = a / Math.Sqrt(1 - (e * sinfp) * (e * sinfp));
double D = x / (N1 * Grids[from].ScaleFactor);
double Q1 = N1 * tanfp / R1;
double Q2 = D * D / 2;
double Q3 = (5 + 3 * T1 + 10 * C1 - 4 * C1 * C1 - 9 * eg2 * eg2) * (D * D * D * D) / 24;
double Q4 = (61 + 90 * T1 + 298 * C1 + 45 * T1 * T1 - 3 * C1 * C1 - 252 * eg2 * eg2) * (D * D * D * D * D * D) / 720;
double Q5 = D;
double Q6 = (1 + 2 * T1 + C1) * (D * D * D) / 6;
double Q7 = (5 - 2 * C1 + 28 * T1 - 3 * C1 * C1 + 8 * eg2 * eg2 + 24 * T1 * T1) * (D * D * D * D * D) / 120;
// result lon
return new LatLon
{
Latitude = fp - Q1 * (Q2 - Q3 + Q4),
Longitude = Grids[from].CentralLongitude + (Q5 - Q6 + Q7) / cosfp
};
}
/// <summary>
/// Israel New Grid (ITM) to WGS84 conversion
/// </summary>
/// <param name="northEast">North East Coordinates in ITM grid</param>
/// <returns>Latitide and Longitude in WGS84</returns>
public LatLon ItmToWgs84(NorthEast northEast)
{
// 1. Local Grid (ITM) -> GRS80
var latLon80 = Grid2LatLon(northEast, ITM, GRS80);
// 2. Molodensky GRS80->WGS84
var latLon84 = Molodensky(latLon80, GRS80, WGS84);
// final results
return ToDegrees(latLon84);
}
/// <summary>
/// Israel Old Grid (ICS) to WGS84 conversion
/// </summary>
/// <param name="northEast">North East Coordinates in ICS grid</param>
/// <returns>Latitide and Longitude in WGS84</returns>
public LatLon IcsToWgs84(NorthEast northEast)
{
// 1. Local Grid (ICS) -> Clark_1880_modified
var latLon80 = Grid2LatLon(northEast, ICS, CLARK80M);
// 2. Molodensky Clark_1880_modified -> WGS84
var latLon84 = Molodensky(latLon80, CLARK80M, WGS84);
// final results
return ToDegrees(latLon84);
}