NETGeographicLib::GeodesicLine Class Reference

.NET wrapper for GeographicLib::GeodesicLine. More...

#include <GeodesicLine.h>

Public Types
enum	mask {   mask::NONE, mask::LATITUDE, mask::LONGITUDE, mask::AZIMUTH,   mask::DISTANCE, mask::DISTANCE_IN, mask::REDUCEDLENGTH, mask::GEODESICSCALE,   mask::AREA, mask::LONG_UNROLL, mask::ALL }

Public Member Functions
	~GeodesicLine ()
Constructors
	GeodesicLine (Geodesic^g, double lat1, double lon1, double azi1, NETGeographicLib::Mask caps)
	GeodesicLine (double lat1, double lon1, double azi1, NETGeographicLib::Mask caps)
	GeodesicLine (const GeographicLib::GeodesicLine &gl)
Position in terms of distance
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%m12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21, [System::Runtime::InteropServices::Out] double%S12)
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2)
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2)
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%m12)
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21)
double	Position (double s12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%m12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21)
Position in terms of arc length
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12, [System::Runtime::InteropServices::Out] double%m12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21, [System::Runtime::InteropServices::Out] double%S12)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12, [System::Runtime::InteropServices::Out] double%m12)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21)
void	ArcPosition (double a12, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12, [System::Runtime::InteropServices::Out] double%m12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21)
The general position function.
double	GenPosition (bool arcmode, double s12_a12, GeodesicLine::mask outmask, [System::Runtime::InteropServices::Out] double%lat2, [System::Runtime::InteropServices::Out] double%lon2, [System::Runtime::InteropServices::Out] double%azi2, [System::Runtime::InteropServices::Out] double%s12, [System::Runtime::InteropServices::Out] double%m12, [System::Runtime::InteropServices::Out] double%M12, [System::Runtime::InteropServices::Out] double%M21, [System::Runtime::InteropServices::Out] double%S12)
Setting point 3
void	SetDistance (double s13)
void	SetArc (double a13)
void	GenSetDistance (bool arcmode, double s13_a13)
Trigonometric accessor functions
void	AzimuthSinCos ([System::Runtime::InteropServices::Out] double%sazi1, [System::Runtime::InteropServices::Out] double%cazi1)
void	EquatorialAzimuthSinCos ([System::Runtime::InteropServices::Out] double%sazi0, [System::Runtime::InteropServices::Out] double%cazi0)
double	GenDistance (bool arcmode)

Private Member Functions
	!GeodesicLine (void)

Private Attributes
GeographicLib::GeodesicLine *	m_pGeodesicLine

Inspector functions
property double	Latitude { double get()
property double	Longitude { double get()
property double	Azimuth { double get()
property double	EquatorialAzimuth { double get()
property double	EquatorialArc { double get()
property double	MajorRadius { double get()
property double	Flattening { double get()
property double	Distance { double get()
property double	Arc { double get()
NETGeographicLib::Mask	Capabilities ()
bool	Capabilities (GeodesicLine::mask testcaps)

Detailed Description

.NET wrapper for GeographicLib::GeodesicLine.

This class allows .NET applications to access GeographicLib::GeodesicLine.

GeodesicLine facilitates the determination of a series of points on a single geodesic. The starting point (lat1, lon1) and the azimuth azi1 are specified in the constructor. GeodesicLine.Position returns the location of point 2 a distance s12 along the geodesic. Alternatively GeodesicLine.ArcPosition gives the position of point 2 an arc length a12 along the geodesic.

The default copy constructor and assignment operators work with this class. Similarly, a vector can be used to hold GeodesicLine objects.

The calculations are accurate to better than 15 nm (15 nanometers). See Sec. 9 of arXiv:1102.1215v1 for details. The algorithms used by this class are based on series expansions using the flattening f as a small parameter. These are only accurate for |f| < 0.02; however reasonably accurate results will be obtained for |f| < 0.2. For very eccentric ellipsoids, use GeodesicLineExact instead.

The algorithms are described in

• C. F. F. Karney, Algorithms for geodesics, J. Geodesy 87, 43–55 (2013); DOI: 10.1007/s00190-012-0578-z; addenda: geod-addenda.html.

For more information on geodesics see geodesic.

C# Example:

using System;
using NETGeographicLib;

namespace example_GeodesicLine
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                // Print waypoints between JFK and SIN
                Geodesic geod = new Geodesic(); // WGS84
                double
                    lat1 = 40.640, lon1 = -73.779, // JFK
                    lat2 = 1.359, lon2 = 103.989; // SIN
                double s12, azi1, azi2,
                    a12 = geod.Inverse(lat1, lon1, lat2, lon2, out s12, out azi1, out azi2);
                GeodesicLine line = new GeodesicLine(geod, lat1, lon1, azi1, Mask.ALL);
                // Alternatively GeodesicLine line = geod.Line(lat1, lon1, azi1, Mask.ALL);
                double ds = 500e3;          // Nominal distance between points = 500 km
                int num = (int)(Math.Ceiling(s12 / ds)); // The number of intervals
                {
                    // Use intervals of equal length
                    ds = s12 / num;
                    for (int i = 0; i <= num; ++i)
                    {
                        double lat, lon;
                        line.Position(i * ds, out lat, out lon);
                        Console.WriteLine(String.Format("i: {0} Latitude: {1} Longitude: {2}", i, lat, lon));
                    }
                }
                {
                    // Slightly faster, use intervals of equal arc length
                    double da = a12 / num;
                    for (int i = 0; i <= num; ++i)
                    {
                        double lat, lon;
                        line.ArcPosition(i * da, out lat, out lon);
                        Console.WriteLine(String.Format("i: {0} Latitude: {1} Longitude: {2}", i, lat, lon));
                    }
                }
            }
            catch (GeographicErr e)
            {
                Console.WriteLine(String.Format("Caught exception: {0}", e.Message));
            }
        }
    }
}

Managed C++ Example:

// Example of using the GeographicLib::GeodesicLine class

#include <iostream>
#include <iomanip>
#include <exception>
#include <cmath>
#include <GeographicLib/Geodesic.hpp>
#include <GeographicLib/GeodesicLine.hpp>
#include <GeographicLib/Constants.hpp>

using namespace std;
using namespace GeographicLib;

int main() {
  try {
    // Print waypoints between JFK and SIN
    Geodesic geod(Constants::WGS84_a(), Constants::WGS84_f());
    // Alternatively: const Geodesic& geod = Geodesic::WGS84();
    double
      lat1 = 40.640, lon1 = -73.779, // JFK
      lat2 =  1.359, lon2 = 103.989; // SIN
    const GeographicLib::GeodesicLine line =
      geod.InverseLine(lat1, lon1, lat2, lon2);
    double ds0 = 500e3;             // Nominal distance between points = 500 km
    int num = int(ceil(line.Distance() / ds0)); // The number of intervals
    cout << fixed << setprecision(3);
    {
      // Use intervals of equal length
      double ds = line.Distance() / num;
      for (int i = 0; i <= num; ++i) {
        double lat, lon;
       line.Position(i * ds, lat, lon);
       cout << i << " " << lat << " " << lon << "\n";
      }
    }
    {
      // Slightly faster, use intervals of equal arc length
      double da = line.Arc() / num;
      for (int i = 0; i <= num; ++i) {
        double lat, lon;
       line.ArcPosition(i * da, lat, lon);
       cout << i << " " << lat << " " << lon << "\n";
      }
    }
  }
  catch (const exception& e) {
    cerr << "Caught exception: " << e.what() << "\n";
    return 1;
  }
}

Visual Basic Example:

Imports NETGeographicLib

Module example_GeodesicLine
    Sub Main()
        Try
            ' Print waypoints between JFK and SIN
            Dim geod As Geodesic = New Geodesic() ' WGS84
            Dim lat1 As Double = 40.64, lon1 = -73.779 ' JFK
            Dim lat2 As Double = 1.359, lon2 = 103.989 ' SIN
            Dim s12, azi1, azi2 As Double
            Dim a12 As Double = geod.Inverse(lat1, lon1, lat2, lon2, s12, azi1, azi2)
            Dim line As GeodesicLine = New GeodesicLine(geod, lat1, lon1, azi1, Mask.ALL)
            ' Alternatively Dim line As GeodesicLineExact = geod.Line(lat1, lon1, azi1, Mask.ALL)
            Dim ds As Double = 500000.0 ' Nominal distance between points = 500 km
            Dim num As Integer = CInt(Math.Ceiling(s12 / ds)) ' The number of intervals
            ' Use intervals of equal length
            ds = s12 / num
            For i As Integer = 0 To num
                Dim lat, lon As Double
                line.Position(i * ds, lat, lon)
                Console.WriteLine(String.Format("i: {0} Latitude: {1} Longitude: {2}", i, lat, lon))
            Next
            ' Slightly faster, use intervals of equal arc length
            Dim da As Double = a12 / num
            For i As Integer = 0 To num
                Dim lat, lon As Double
                line.ArcPosition(i * da, lat, lon)
                Console.WriteLine(String.Format("i: {0} Latitude: {1} Longitude: {2}", i, lat, lon))
            Next
        Catch ex As GeographicErr
            Console.WriteLine(String.Format("Caught exception: {0}", ex.Message))
        End Try
    End Sub
End Module

INTERFACE DIFFERENCES:
A constructor has been provided which assumes WGS84 parameters.

The following functions are implemented as properties: Latitude, Longitude, Azimuth, EquatorialAzimuth, EquatorialArc, MajorRadius, Distance, Arc, and Flattening.

The constructors, Capabilities, and GenPosition functions accept the "capabilities mask" as a NETGeographicLib::Mask rather than an unsigned. The Capabilities function returns a NETGeographicLib::Mask rather than an unsigned.

The overloaded Azimuth and EquatorialAzimuth functions that return the sin and cosine terms have been renamed AzimuthSinCos and EquatorialAzimuthSinCos, repectively.

Definition at line 75 of file GeodesicLine.h.

Member Enumeration Documentation

enum NETGeographicLib::GeodesicLine::mask

strong

Bit masks for what calculations to do. They signify to the GeodesicLine::GeodesicLine constructor and to Geodesic::Line what capabilities should be included in the GeodesicLine object. This is merely a duplication of Geodesic::mask.

Enumerator
NONE	No capabilities, no output.
LATITUDE	Calculate latitude lat2. (It's not necessary to include this as a capability to GeodesicLine because this is included by default.)
LONGITUDE	Calculate longitude lon2.
AZIMUTH	Calculate azimuths azi1 and azi2. (It's not necessary to include this as a capability to GeodesicLine because this is included by default.)
DISTANCE	Calculate distance s12.
DISTANCE_IN	Allow distance s12 to be used as input in the direct geodesic problem.
REDUCEDLENGTH	Calculate reduced length m12.
GEODESICSCALE	Calculate geodesic scales M12 and M21.
AREA	Calculate area S12.
LONG_UNROLL	Unroll lon2 in the direct calculation.
ALL	All capabilities, calculate everything. (LONG_UNROLL is not included in this mask.)

Definition at line 91 of file GeodesicLine.h.

Constructor & Destructor Documentation

GeodesicLine::!GeodesicLine ( void  )

private

Definition at line 21 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

GeodesicLine::GeodesicLine	(	Geodesic^	g,
		double	lat1,
		double	lon1,
		double	azi1,
		NETGeographicLib::Mask	caps
	)

Constructor for a geodesic line staring at latitude lat1, longitude lon1, and azimuth azi1 (all in degrees).

Parameters

[in]	g	A Geodesic object used to compute the necessary information about the GeodesicLine.
[in]	lat1	latitude of point 1 (degrees).
[in]	lon1	longitude of point 1 (degrees).
[in]	azi1	azimuth at point 1 (degrees).
[in]	caps	bitor'ed combination of NETGeographicLib::Mask values specifying the capabilities the GeodesicLine object should possess, i.e., which quantities can be returned in calls to GeodesicLine::Position.

lat1 should be in the range [−90°, 90°].

The NETGeographicLib::Mask values are

• caps |= GeodesicLine::LATITUDE for the latitude lat2; this is added automatically;
• caps |= GeodesicLine::LONGITUDE for the latitude lon2;
• caps |= GeodesicLine::AZIMUTH for the latitude azi2; this is added automatically;
• caps |= GeodesicLine::DISTANCE for the distance s12;
• caps |= GeodesicLine::REDUCEDLENGTH for the reduced length m12;
• caps |= GeodesicLine::GEODESICSCALE for the geodesic scales M12 and M21;
• caps |= GeodesicLine::AREA for the area S12;
• caps |= GeodesicLine::DISTANCE_IN permits the length of the geodesic to be given in terms of s12; without this capability the length can only be specified in terms of arc length;
• caps |= GeodesicLine::ALL for all of the above.

The default value of caps is GeodesicLine::ALL.

If the point is at a pole, the azimuth is defined by keeping lon1 fixed, writing lat1 = ±(90° − ε), and taking the limit ε → 0+.

Definition at line 31 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

GeodesicLine::GeodesicLine	(	double	lat1,
		double	lon1,
		double	azi1,
		NETGeographicLib::Mask	caps
	)

A constructor which assumes the WGS84 ellipsoid.

Definition at line 62 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

GeodesicLine::GeodesicLine

(

const GeographicLib::GeodesicLine &

gl

)

A constructoe that accepts a reference to an unmanages GeodesicLin. FOR INTERNAL USE ONLY

Definition at line 49 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

NETGeographicLib::GeodesicLine::~GeodesicLine ( )

inline

The destructor calls the finalizer.

Definition at line 214 of file GeodesicLine.h.

Member Function Documentation

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12,
		[System::Runtime::InteropServices::Out] double%	m12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21,
		[System::Runtime::InteropServices::Out] double%	S12
	)

Compute the position of point 2 which is an arc length a12 (degrees) from point 1.

Parameters

[in]	a12	arc length between point 1 and point 2 (degrees); it can be negative.
[out]	lat2	latitude of point 2 (degrees).
[out]	lon2	longitude of point 2 (degrees); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::LONGITUDE.
[out]	azi2	(forward) azimuth at point 2 (degrees).
[out]	s12	distance between point 1 and point 2 (meters); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::DISTANCE.
[out]	m12	reduced length of geodesic (meters); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::REDUCEDLENGTH.
[out]	M12	geodesic scale of point 2 relative to point 1 (dimensionless); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::GEODESICSCALE.
[out]	M21	geodesic scale of point 1 relative to point 2 (dimensionless); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::GEODESICSCALE.
[out]	S12	area under the geodesic (meters2); requires that the GeodesicLine object was constructed with caps |= NETGeographicLib::Mask::AREA.

The values of lon2 and azi2 returned are in the range [−180°, 180°).

Requesting a value which the GeodesicLine object is not capable of computing is not an error; the corresponding argument will not be altered.

The following functions are overloaded versions of GeodesicLine::ArcPosition which omit some of the output parameters.

Definition at line 184 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 208 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 219 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 232 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12,
		[System::Runtime::InteropServices::Out] double%	m12
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 247 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 264 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::ArcPosition	(	double	a12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12,
		[System::Runtime::InteropServices::Out] double%	m12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21
	)

See the documentation for GeodesicLine::ArcPosition.

Definition at line 284 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::AzimuthSinCos	(	[System::Runtime::InteropServices::Out] double%	sazi1,
		[System::Runtime::InteropServices::Out] double%	cazi1
	)

The sine and cosine of azi1.

Parameters

[out]	sazi1	the sine of azi1.
[out]	cazi1	the cosine of azi1.

Definition at line 386 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

NETGeographicLib::Mask GeodesicLine::Capabilities

(

)

Returns

caps the computational capabilities that this object was constructed with. LATITUDE and AZIMUTH are always included.

Definition at line 366 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

bool GeodesicLine::Capabilities

(

GeodesicLine::mask

testcaps

)

Parameters

[in]

testcaps

a set of bitor'ed GeodesicLine::mask values.

Returns

true if the GeodesicLine object has all these capabilities.

Definition at line 370 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::EquatorialAzimuthSinCos	(	[System::Runtime::InteropServices::Out] double%	sazi0,
		[System::Runtime::InteropServices::Out] double%	cazi0
	)

The sine and cosine of azi0.

Parameters

[out]	sazi0	the sine of azi0.
[out]	cazi0	the cosine of azi0.

Definition at line 395 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::GenDistance

(

bool

arcmode

)

The distance or arc length to point 3.

Parameters

[in]

arcmode

boolean flag determining the meaning of returned value.

Returns

s13 if arcmode is false; a13 if arcmode is true.

Definition at line 404 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::GenPosition	(	bool	arcmode,
		double	s12_a12,
		GeodesicLine::mask	outmask,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	s12,
		[System::Runtime::InteropServices::Out] double%	m12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21,
		[System::Runtime::InteropServices::Out] double%	S12
	)

The general position function. GeodesicLine::Position and GeodesicLine::ArcPosition are defined in terms of this function.

Parameters

[in]	arcmode	boolean flag determining the meaning of the second parameter; if arcmode is false, then the GeodesicLine object must have been constructed with caps |= GeodesicLine::DISTANCE_IN.
[in]	s12_a12	if arcmode is false, this is the distance between point 1 and point 2 (meters); otherwise it is the arc length between point 1 and point 2 (degrees); it can be negative.
[in]	outmask	a bitor'ed combination of GeodesicLine::mask values specifying which of the following parameters should be set.
[out]	lat2	latitude of point 2 (degrees).
[out]	lon2	longitude of point 2 (degrees); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::LONGITUDE.
[out]	azi2	(forward) azimuth at point 2 (degrees).
[out]	s12	distance between point 1 and point 2 (meters); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::DISTANCE.
[out]	m12	reduced length of geodesic (meters); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::REDUCEDLENGTH.
[out]	M12	geodesic scale of point 2 relative to point 1 (dimensionless); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::GEODESICSCALE.
[out]	M21	geodesic scale of point 1 relative to point 2 (dimensionless); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::GEODESICSCALE.
[out]	S12	area under the geodesic (meters2); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::AREA.

Returns

a12 arc length of between point 1 and point 2 (degrees).

The GeodesicLine::mask values possible for outmask are

• outmask |= GeodesicLine::LATITUDE for the latitude lat2;
• outmask |= GeodesicLine::LONGITUDE for the latitude lon2;
• outmask |= GeodesicLine::AZIMUTH for the latitude azi2;
• outmask |= GeodesicLine::DISTANCE for the distance s12;
• outmask |= GeodesicLine::REDUCEDLENGTH for the reduced length m12;
• outmask |= GeodesicLine::GEODESICSCALE for the geodesic scales M12 and M21;
• outmask |= GeodesicLine::AREA for the area S12;
• outmask |= GeodesicLine::ALL for all of the above;
• outmask |= GeodesicLine::LONG_UNROLL to unroll lon2 instead of wrapping it into the range [−180°, 180°).

Requesting a value which the GeodesicLine object is not capable of computing is not an error; the corresponding argument will not be altered. Note, however, that the arc length is always computed and returned as the function value.

With the LONG_UNROLL bit set, the quantity lon2 − lon1 indicates how many times and in what sense the geodesic encircles the ellipsoid.

Definition at line 306 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::GenSetDistance	(	bool	arcmode,
		double	s13_a13
	)

Specify position of point 3 in terms of either distance or arc length.

Parameters

[in]	arcmode	boolean flag determining the meaning of the second parameter; if arcmode is false, then the GeodesicLine object must have been constructed with caps |= GeodesicLine::DISTANCE_IN.
[in]	s13_a13	if arcmode is false, this is the distance from point 1 to point 3 (meters); otherwise it is the arc length from point 1 to point 3 (degrees); it can be negative.

Definition at line 382 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	m12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21,
		[System::Runtime::InteropServices::Out] double%	S12
	)

Compute the position of point 2 which is a distance s12 (meters) from point 1.

Parameters

[in]	s12	distance between point 1 and point 2 (meters); it can be negative.
[out]	lat2	latitude of point 2 (degrees).
[out]	lon2	longitude of point 2 (degrees); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::LONGITUDE.
[out]	azi2	(forward) azimuth at point 2 (degrees).
[out]	m12	reduced length of geodesic (meters); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::REDUCEDLENGTH.
[out]	M12	geodesic scale of point 2 relative to point 1 (dimensionless); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::GEODESICSCALE.
[out]	M21	geodesic scale of point 1 relative to point 2 (dimensionless); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::GEODESICSCALE.
[out]	S12	area under the geodesic (meters2); requires that the GeodesicLine object was constructed with caps |= GeodesicLine::AREA.

Returns

a12 arc length of between point 1 and point 2 (degrees).

The values of lon2 and azi2 returned are in the range [−180°, 180°).

The GeodesicLine object must have been constructed with caps |= GeodesicLine::DISTANCE_IN; otherwise Math::NaN() is returned and no parameters are set. Requesting a value which the GeodesicLine object is not capable of computing is not an error; the corresponding argument will not be altered.

The following functions are overloaded versions of GeodesicLine::Position which omit some of the output parameters. Note, however, that the arc length is always computed and returned as the function value.

Definition at line 78 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2
	)

See the documentation for GeodesicLine::Position.

Definition at line 101 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2
	)

See the documentation for GeodesicLine::Position.

Definition at line 113 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	m12
	)

See the documentation for GeodesicLine::Position.

Definition at line 127 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21
	)

See the documentation for GeodesicLine::Position.

Definition at line 144 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

double GeodesicLine::Position	(	double	s12,
		[System::Runtime::InteropServices::Out] double%	lat2,
		[System::Runtime::InteropServices::Out] double%	lon2,
		[System::Runtime::InteropServices::Out] double%	azi2,
		[System::Runtime::InteropServices::Out] double%	m12,
		[System::Runtime::InteropServices::Out] double%	M12,
		[System::Runtime::InteropServices::Out] double%	M21
	)

See the documentation for GeodesicLine::Position.

Definition at line 163 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::SetArc

(

double

a13

)

Specify position of point 3 in terms of arc length.

Parameters

[in]

a13

the arc length from point 1 to point 3 (degrees); it can be negative.

The distance s13 is only set if the GeodesicLine object has been constructed with caps |= GeodesicLine::DISTANCE.

Definition at line 378 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

void GeodesicLine::SetDistance

(

double

s13

)

Specify position of point 3 in terms of distance.

Parameters

[in]

s13

the distance from point 1 to point 3 (meters); it can be negative.

This is only useful if the GeodesicLine object has been constructed with caps |= GeodesicLine::DISTANCE_IN.

Definition at line 374 of file dotnet/NETGeographicLib/GeodesicLine.cpp.

Member Data Documentation

property double NETGeographicLib::GeodesicLine::Arc { double get()

Returns

a13, the arc length to point 3 (degrees).

Definition at line 621 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::Azimuth { double get()

Returns

azi1 the azimuth (degrees) of the geodesic line at point 1.

Definition at line 587 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::Distance { double get()

Returns

s13, the distance to point 3 (meters).

Definition at line 616 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::EquatorialArc { double get()

Returns

a1 the arc length (degrees) between the northward equatorial crossing and point 1.

Definition at line 599 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::EquatorialAzimuth { double get()

Returns

azi0 the azimuth (degrees) of the geodesic line as it crosses the equator in a northward direction.

Definition at line 593 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::Flattening { double get()

Returns

f the flattening of the ellipsoid. This is the value inherited from the Geodesic object used in the constructor.

Definition at line 611 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::Latitude { double get()

Returns

lat1 the latitude of point 1 (degrees).

Definition at line 577 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::Longitude { double get()

Returns

lon1 the longitude of point 1 (degrees).

Definition at line 582 of file GeodesicLine.h.

GeographicLib::GeodesicLine* NETGeographicLib::GeodesicLine::m_pGeodesicLine

private

Definition at line 79 of file GeodesicLine.h.

property double NETGeographicLib::GeodesicLine::MajorRadius { double get()

Returns

a the equatorial radius of the ellipsoid (meters). This is the value inherited from the Geodesic object used in the constructor.

Definition at line 605 of file GeodesicLine.h.

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The documentation for this class was generated from the following files:

• GeodesicLine.h
• dotnet/NETGeographicLib/GeodesicLine.cpp