internal void AlignSigFigs(GridReference source)
{
int SigFigsSrc;
int SigFigsDest;
SigFigsSrc = Converter.GetSigFigs(source.Easting);
SigFigsDest = Converter.GetSigFigs(this.Easting);
this.Easting = (int)Converter.SetSigFigs(
(double)this.Easting,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
source.Easting = (int)Converter.SetSigFigs(
(double)source.Easting,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
SigFigsSrc = Converter.GetSigFigs(source.Northing);
SigFigsDest = Converter.GetSigFigs(this.Northing);
this.Northing = (int)Converter.SetSigFigs(
(double)this.Northing,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
source.Northing = (int)Converter.SetSigFigs(
(double)source.Northing,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
}
internal void AlignSigFigs(GridReference source)
{
int SigFigsSrc;
int SigFigsDest;
SigFigsSrc = Converter.GetSigFigs(source.Easting);
SigFigsDest = Converter.GetSigFigs(this.Easting);
this.Easting = (int)Converter.SetSigFigs(
(double)this.Easting,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
source.Easting = (int)Converter.SetSigFigs(
(double)source.Easting,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
SigFigsSrc = Converter.GetSigFigs(source.Northing);
SigFigsDest = Converter.GetSigFigs(this.Northing);
this.Northing = (int)Converter.SetSigFigs(
(double)this.Northing,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
source.Northing = (int)Converter.SetSigFigs(
(double)source.Northing,
SigFigsDest < SigFigsSrc ? SigFigsDest : SigFigsSrc);
}
/// <summary>
/// Converts northing and easting coordinates into Longitude/Latitude coordinates in the WGS84 coordinate system.
/// </summary>
/// <param name="northing">northing coordinate</param>
/// <param name="easting">easting coordinate</param>
/// <returns>converted coordinates</returns>
protected PolarGeoCoordinate ConvertToLonLat(double northing, double easting)
{
// Use GeoCoordConversion DLL to convert the Eastings & Northings to Lon/Lat
// coordinates in the WGS84 system. The DLL was pulled from: http://code.google.com/p/geocoordconversion/
// and is available under the GNU General Public License v3: http://www.gnu.org/licenses/gpl.html
GridReference gridRef = new GridReference((long)easting, (long)northing);
PolarGeoCoordinate polarCoord = GridReference.ChangeToPolarGeo(gridRef);
return PolarGeoCoordinate.ChangeCoordinateSystem(polarCoord, CoordinateSystems.WGS84);
}
internal static PolarGeoCoordinate GridReferenceToGeodesic(GridReference g)
{
double lat = _NatGridTrueOrigin.Lat;
double M = 0;
do
{
lat = (g.Northing - _NatNETrueOrigin.Northing - M) / (_Airy1830.SemimajorAxis * _NatGridScaleFactor)
+ lat;
double Ma = (1 + _n + (5d / 4d) * _n2 + (5d / 4d) * _n3) * (lat - _NatGridTrueOrigin.Lat);
double Mb = (3 * _n + 3 * _n * _n + (21d / 8d) * _n3) * Math.Sin(lat - _NatGridTrueOrigin.Lat)
* Math.Cos(lat + _NatGridTrueOrigin.Lat);
double Mc = ((15d / 8d) * _n2 + (15d / 8d) * _n3) * Math.Sin(2 * (lat - _NatGridTrueOrigin.Lat))
* Math.Cos(2 * (lat + _NatGridTrueOrigin.Lat));
double Md = (35d / 24d) * _n3 * Math.Sin(3 * (lat - _NatGridTrueOrigin.Lat))
* Math.Cos(3 * (lat + _NatGridTrueOrigin.Lat));
M = _Airy1830.SemiMinorAxis * _NatGridScaleFactor * (Ma - Mb + Mc - Md); // meridional arc
}while (g.Northing - _NatNETrueOrigin.Northing - M >= 0.00001); // ie until < 0.01mm
double cosLat = Math.Cos(lat), sinLat = Math.Sin(lat);
double nu = _Airy1830.SemimajorAxis * _NatGridScaleFactor / Math.Sqrt(1 - _e2 * sinLat * sinLat);
// transverse radius of curvature
double rho = _Airy1830.SemimajorAxis * _NatGridScaleFactor * (1 - _e2)
/ Math.Pow(1 - _e2 * sinLat * sinLat, 1.5); // meridional radius of curvature
double eta2 = nu / rho - 1;
double tanLat = Math.Tan(lat);
double tan2lat = tanLat * tanLat, tan4lat = tan2lat * tan2lat, tan6lat = tan4lat * tan2lat;
double secLat = 1 / cosLat;
double nu3 = nu * nu * nu, nu5 = nu3 * nu * nu, nu7 = nu5 * nu * nu;
double VII = tanLat / (2 * rho * nu);
double VIII = tanLat / (24 * rho * nu3) * (5 + 3 * tan2lat + eta2 - 9 * tan2lat * eta2);
double IX = tanLat / (720 * rho * nu5) * (61 + 90 * tan2lat + 45 * tan4lat);
double X = secLat / nu;
double XI = secLat / (6 * nu3) * (nu / rho + 2 * tan2lat);
double XII = secLat / (120 * nu5) * (5 + 28 * tan2lat + 24 * tan4lat);
double XIIA = secLat / (5040 * nu7) * (61 + 662 * tan2lat + 1320 * tan4lat + 720 * tan6lat);
double dE = g.Easting - _NatNETrueOrigin.Easting;
double dE2 = dE * dE;
double dE3 = dE2 * dE;
double dE4 = dE2 * dE2;
double dE5 = dE3 * dE2;
double dE6 = dE4 * dE2;
double dE7 = dE5 * dE2;
lat = lat - VII * dE2 + VIII * dE4 - IX * dE6;
double lon = _NatGridTrueOrigin.Lon + X * dE - XI * dE3 + XII * dE5 - XIIA * dE7;
var retVal = new PolarGeoCoordinate(lat, lon, 0, AngleUnit.Radians, CoordinateSystems.OSGB36);
retVal = PolarGeoCoordinate.ChangeUnits(retVal, AngleUnit.Degrees);
retVal.SetSigFigs(7);
return(retVal);
}
public bool IsTheSameAs(GridReference compareTo)
{
if (
compareTo.Northing != this.Northing
|| compareTo.Easting != this.Easting
)
return false;
else
return true;
}
internal static GridReference ReduceSigFigsBy1(GridReference original)
{
double Northing = Converter.SetSigFigs(
original.Northing,
Converter.GetSigFigs(original.Northing) - 1);
double Easting = Converter.SetSigFigs(
original.Easting,
Converter.GetSigFigs(original.Easting) - 1);
return(new GridReference((int)Easting, (int)Northing));
}
internal static GridReference ReduceSigFigsBy1(GridReference original)
{
double Northing = Converter.SetSigFigs(
original.Northing,
Converter.GetSigFigs(original.Northing) - 1);
double Easting = Converter.SetSigFigs(
original.Easting,
Converter.GetSigFigs(original.Easting) - 1);
return new GridReference((int)Easting, (int)Northing);
}
//overload of IsTheSameAs to ignore rounding errors on final digit
public bool IsTheSameAs(GridReference compareTo, bool ignoreFinalDigit)
{
if (ignoreFinalDigit)
{
AlignSigFigs(compareTo);
GridReference compareToReduced = ReduceSigFigsBy1(compareTo);
GridReference comparer = ReduceSigFigsBy1(this);
return comparer.IsTheSameAs(compareToReduced);
}
return IsTheSameAs(compareTo);
}
//overload of IsTheSameAs to ignore rounding errors on final digit
public bool IsTheSameAs(GridReference compareTo, bool ignoreFinalDigit)
{
if (ignoreFinalDigit)
{
AlignSigFigs(compareTo);
GridReference compareToReduced = ReduceSigFigsBy1(compareTo);
GridReference comparer = ReduceSigFigsBy1(this);
return(comparer.IsTheSameAs(compareToReduced));
}
return(IsTheSameAs(compareTo));
}
public bool IsTheSameAs(GridReference compareTo)
{
if (
compareTo.Northing != this.Northing ||
compareTo.Easting != this.Easting
)
{
return(false);
}
else
{
return(true);
}
}
public static PolarGeoCoordinate ChangeToPolarGeo(GridReference original)
{
return Converter.GridReferenceToGeodesic(original);
}
internal static PolarGeoCoordinate GridReferenceToGeodesic(GridReference g)
{
double lat = _NatGridTrueOrigin.Lat;
double M = 0;
do
{
lat = (g.Northing - _NatNETrueOrigin.Northing - M) / (_Airy1830.SemimajorAxis * _NatGridScaleFactor)
+ lat;
double Ma = (1 + _n + (5d / 4d) * _n2 + (5d / 4d) * _n3) * (lat - _NatGridTrueOrigin.Lat);
double Mb = (3 * _n + 3 * _n * _n + (21d / 8d) * _n3) * Math.Sin(lat - _NatGridTrueOrigin.Lat)
* Math.Cos(lat + _NatGridTrueOrigin.Lat);
double Mc = ((15d / 8d) * _n2 + (15d / 8d) * _n3) * Math.Sin(2 * (lat - _NatGridTrueOrigin.Lat))
* Math.Cos(2 * (lat + _NatGridTrueOrigin.Lat));
double Md = (35d / 24d) * _n3 * Math.Sin(3 * (lat - _NatGridTrueOrigin.Lat))
* Math.Cos(3 * (lat + _NatGridTrueOrigin.Lat));
M = _Airy1830.SemiMinorAxis * _NatGridScaleFactor * (Ma - Mb + Mc - Md); // meridional arc
}
while (g.Northing - _NatNETrueOrigin.Northing - M >= 0.00001); // ie until < 0.01mm
double cosLat = Math.Cos(lat), sinLat = Math.Sin(lat);
double nu = _Airy1830.SemimajorAxis * _NatGridScaleFactor / Math.Sqrt(1 - _e2 * sinLat * sinLat);
// transverse radius of curvature
double rho = _Airy1830.SemimajorAxis * _NatGridScaleFactor * (1 - _e2)
/ Math.Pow(1 - _e2 * sinLat * sinLat, 1.5); // meridional radius of curvature
double eta2 = nu / rho - 1;
double tanLat = Math.Tan(lat);
double tan2lat = tanLat * tanLat, tan4lat = tan2lat * tan2lat, tan6lat = tan4lat * tan2lat;
double secLat = 1 / cosLat;
double nu3 = nu * nu * nu, nu5 = nu3 * nu * nu, nu7 = nu5 * nu * nu;
double VII = tanLat / (2 * rho * nu);
double VIII = tanLat / (24 * rho * nu3) * (5 + 3 * tan2lat + eta2 - 9 * tan2lat * eta2);
double IX = tanLat / (720 * rho * nu5) * (61 + 90 * tan2lat + 45 * tan4lat);
double X = secLat / nu;
double XI = secLat / (6 * nu3) * (nu / rho + 2 * tan2lat);
double XII = secLat / (120 * nu5) * (5 + 28 * tan2lat + 24 * tan4lat);
double XIIA = secLat / (5040 * nu7) * (61 + 662 * tan2lat + 1320 * tan4lat + 720 * tan6lat);
double dE = g.Easting - _NatNETrueOrigin.Easting;
double dE2 = dE * dE;
double dE3 = dE2 * dE;
double dE4 = dE2 * dE2;
double dE5 = dE3 * dE2;
double dE6 = dE4 * dE2;
double dE7 = dE5 * dE2;
lat = lat - VII * dE2 + VIII * dE4 - IX * dE6;
double lon = _NatGridTrueOrigin.Lon + X * dE - XI * dE3 + XII * dE5 - XIIA * dE7;
var retVal = new PolarGeoCoordinate(lat, lon, 0, AngleUnit.Radians, CoordinateSystems.OSGB36);
retVal = PolarGeoCoordinate.ChangeUnits(retVal, AngleUnit.Degrees);
retVal.SetSigFigs(7);
return retVal;
}
public static PolarGeoCoordinate ChangeToPolarGeo(GridReference original)
{
return(Converter.GridReferenceToGeodesic(original));
}
