public GeoCoordinate ConvertToWGS84(double x, double y)
{
double d1 = System.Math.Pow(System.Math.Sqrt(System.Math.Pow(x - this._x_origin, 2.0) + System.Math.Pow(this._r_0 - (y - this._y_origin), 2.0)) / (this._ellipsoid.SemiMajorAxis * this._g), 1.0 / this._n);
double num1 = System.Math.Atan((x - this._x_origin) / (this._r_0 - (y - this._y_origin))) / this._n + this._longitude_origin_radians;
double a = System.Math.PI / 2.0 - 2.0 * System.Math.Atan(d1);
double eccentricity1 = this._ellipsoid.Eccentricity;
for (double num2 = 0.0; num2 != a; a = System.Math.PI / 2.0 - 2.0 * System.Math.Atan(d1 * System.Math.Pow((1.0 - eccentricity1 * System.Math.Sin(a)) / (1.0 + eccentricity1 * System.Math.Sin(a)), eccentricity1 / 2.0)))
{
num2 = a;
}
Hayford1924Ellipsoid hayford1924Ellipsoid = new Hayford1924Ellipsoid();
double num3 = a;
double num4 = num1;
double num5 = 100.0;
double semiMajorAxis1 = hayford1924Ellipsoid.SemiMajorAxis;
double eccentricity2 = hayford1924Ellipsoid.Eccentricity;
double num6 = eccentricity2 * eccentricity2;
double num7 = System.Math.Sin(num3);
double num8 = System.Math.Cos(num3);
double num9 = System.Math.Sin(num4);
double num10 = System.Math.Cos(num4);
double num11 = semiMajorAxis1 / System.Math.Sqrt(1.0 - num6 * num7 * num7);
double num12 = (num11 + num5) * num8 * num10;
double num13 = (num11 + num5) * num8 * num9;
double num14 = ((1.0 - num6) * num11 + num5) * num7;
double num15 = 106.868628;
double num16 = 52.297783;
double num17 = 103.723893;
double num18 = num12 - num15;
double num19 = num13 + num16;
double num20 = num17;
double num21 = num14 - num20;
double num22 = new Degree(9.34916666666667E-05).Value;
double num23 = System.Math.Sin(num22);
double num24 = System.Math.Cos(num22);
double num25 = new Degree(-0.000126931944444444).Value;
double num26 = System.Math.Sin(num25);
double num27 = System.Math.Cos(num25);
double num28 = new Degree(0.0005117175).Value;
double num29 = System.Math.Sin(num28);
double num30 = System.Math.Cos(num28);
double num31 = num19 * num24 - num21 * num23;
double num32 = num31 * num23 + num21 * num24;
double num33 = num18 * num27 + num32 * num26;
double num34 = num33 * -num26 + num32 * num27;
double num35 = num33 * num30 - num31 * num29;
double num36 = num35 * num29 + num31 * num30;
Wgs1984Ellipsoid wgs1984Ellipsoid = new Wgs1984Ellipsoid();
double eccentricity3 = wgs1984Ellipsoid.Eccentricity;
double num37 = eccentricity3 * eccentricity3;
double d2 = num35 * num35 + num36 * num36;
double num38 = System.Math.Sqrt(d2);
double num39 = num34 * num34;
double num40 = System.Math.Sqrt(d2 + num39);
double flattening = wgs1984Ellipsoid.Flattening;
double semiMajorAxis2 = wgs1984Ellipsoid.SemiMajorAxis;
double num41 = System.Math.Atan(num34 / num38 * (1.0 - flattening + num37 * semiMajorAxis2 / num40));
double num42 = System.Math.Atan(num36 / num35);
return(new GeoCoordinate(new Radian(System.Math.Atan((num34 * (1.0 - flattening) + num37 * semiMajorAxis2 * System.Math.Pow(System.Math.Sin(num41), 3.0)) / ((1.0 - flattening) * (num38 - num37 * semiMajorAxis2 * System.Math.Pow(System.Math.Cos(num41), 3.0))))).Value,
new Radian(num42).Value));
}
/// <summary>
/// Converts the given lambert coordinates to mercator coordinates.
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <returns></returns>
public GeoCoordinate ConvertToWGS84(double x, double y)
{
double latitude;
double longitude;
double r = (System.Math.Sqrt(
System.Math.Pow(x - _x_origin, 2.0) +
System.Math.Pow((_r_0 - (y - _y_origin)), 2.0))
);
double t = System.Math.Pow((r / (_ellipsoid.SemiMajorAxis * _g)), 1.0 / _n);
double phi = System.Math.Atan((x - _x_origin) /
(_r_0 - (y - _y_origin)));
longitude = ((phi / _n) + _longitude_origin_radians);
latitude = (System.Math.PI / 2.0 - 2.0 * System.Math.Atan(t));
double e = _ellipsoid.Eccentricity;
double new_latitude = 0;
while (new_latitude != latitude)
{ // iterate 100 times.
new_latitude = latitude;
latitude = (System.Math.PI / 2.0 - 2.0 *
System.Math.Atan(t *
System.Math.Pow(
((1.0 - e * System.Math.Sin(latitude)) / (1.0 + e * System.Math.Sin(latitude))),
e / 2.0)));
}
Hayford1924Ellipsoid hayford = new Hayford1924Ellipsoid();
double phi_72 = latitude; // phi = latitude!
double lambda_72 = longitude; // lambda = longitude!
double h_72 = 100;
double a_72 = hayford.SemiMajorAxis;
double e_72 = hayford.Eccentricity;
double es_72 = e_72 * e_72;
double sin_phi_72 = System.Math.Sin(phi_72);
double cos_phi_72 = System.Math.Cos(phi_72);
double sin_lambda_72 = System.Math.Sin(lambda_72);
double cos_lambda_72 = System.Math.Cos(lambda_72);
double v_72 = a_72 / System.Math.Sqrt(1 - (es_72 * sin_phi_72 * sin_phi_72));
double X_72 = (v_72 + h_72) * cos_phi_72 * cos_lambda_72;
double Y_72 = (v_72 + h_72) * cos_phi_72 * sin_lambda_72;
double Z_72 = ((1 - es_72) * v_72 + h_72) * sin_phi_72;
// ALL OK
//X_72 = X_72 * (1 / 1.0000012747);
//Y_72 = Y_72 * (1 / 1.0000012747);
//Z_72 = Z_72 * (1 / 1.0000012747);
// translations.
double x_trans = 106.868628;
double y_trans = 52.297783;
double z_trans = 103.723893;
double X_89 = X_72 - x_trans;
double Y_89 = Y_72 + y_trans;
double Z_89 = Z_72 - z_trans;
// rotations.
double x_angle = ((Radian) new Degree(0.336570 / 3600)).Value;
double sin_x_angle = System.Math.Sin(x_angle);
double cos_x_angle = System.Math.Cos(x_angle);
double y_angle = ((Radian) new Degree(-0.456955 / 3600)).Value;
double sin_y_angle = System.Math.Sin(y_angle);
double cos_y_angle = System.Math.Cos(y_angle);
double z_angle = ((Radian) new Degree(1.842183 / 3600)).Value;
double sin_z_angle = System.Math.Sin(z_angle);
double cos_z_angle = System.Math.Cos(z_angle);
// rotate around x.
//X_89 = X_89;
Y_89 = Y_89 * cos_x_angle - Z_89 * sin_x_angle;
Z_89 = Y_89 * sin_x_angle + Z_89 * cos_x_angle;
// rotate around y.
X_89 = X_89 * cos_y_angle + Z_89 * sin_y_angle;
//Y_89 = Y_89;
Z_89 = X_89 * (-sin_y_angle) + Z_89 * cos_y_angle;
// rotate around Z.
X_89 = X_89 * cos_z_angle - Y_89 * sin_z_angle;
Y_89 = X_89 * sin_z_angle + Y_89 * cos_z_angle;
//Z_89 = Z_89;
Wgs1984Ellipsoid wgs1984 = new Wgs1984Ellipsoid();
e = wgs1984.Eccentricity;
double es = e * e;
double ps = X_89 * X_89 + Y_89 * Y_89;
double p = System.Math.Sqrt(ps);
r = System.Math.Sqrt(ps + Z_89 * Z_89);
double f = wgs1984.Flattening;
double a = wgs1984.SemiMajorAxis;
double u = System.Math.Atan((Z_89 / p) * ((1 - f) + (es * a / r)));
double lambda = System.Math.Atan(Y_89 / X_89);
phi = System.Math.Atan((Z_89 * (1 - f) + (es * a * System.Math.Pow(System.Math.Sin(u), 3)))
/
((1 - f) * (p - (es * a * System.Math.Pow(System.Math.Cos(u), 3)))));
Degree longitude_84 = new Radian(lambda);
Degree latitude_84 = new Radian(phi);
return(new GeoCoordinate(latitude_84.Value, longitude_84.Value));
}
