674 lines
28 KiB
C++
674 lines
28 KiB
C++
/**
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* \file GeodesicLineExact.hpp
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* \brief Header for GeographicLib::GeodesicLineExact class
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*
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* Copyright (c) Charles Karney (2012-2020) <charles@karney.com> and licensed
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* under the MIT/X11 License. For more information, see
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* https://geographiclib.sourceforge.io/
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**********************************************************************/
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#if !defined(GEOGRAPHICLIB_GEODESICLINEEXACT_HPP)
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#define GEOGRAPHICLIB_GEODESICLINEEXACT_HPP 1
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#include <GeographicLib/Constants.hpp>
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#include <GeographicLib/GeodesicExact.hpp>
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#include <GeographicLib/EllipticFunction.hpp>
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namespace GeographicLib {
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/**
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* \brief An exact geodesic line
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*
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* GeodesicLineExact facilitates the determination of a series of points on a
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* single geodesic. This is a companion to the GeodesicExact class. For
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* additional information on this class see the documentation on the
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* GeodesicLine class.
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*
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* Example of use:
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* \include example-GeodesicLineExact.cpp
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*
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* <a href="GeodSolve.1.html">GeodSolve</a> is a command-line utility
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* providing access to the functionality of GeodesicExact and
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* GeodesicLineExact (via the -E option).
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**********************************************************************/
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class GEOGRAPHICLIB_EXPORT GeodesicLineExact {
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private:
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typedef Math::real real;
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friend class GeodesicExact;
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static const int nC4_ = GeodesicExact::nC4_;
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real tiny_;
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real _lat1, _lon1, _azi1;
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real _a, _f, _b, _c2, _f1, _e2, _salp0, _calp0, _k2,
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_salp1, _calp1, _ssig1, _csig1, _dn1, _stau1, _ctau1,
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_somg1, _comg1, _cchi1,
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_A4, _B41, _E0, _D0, _H0, _E1, _D1, _H1;
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real _a13, _s13;
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real _C4a[nC4_]; // all the elements of _C4a are used
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EllipticFunction _E;
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unsigned _caps;
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void LineInit(const GeodesicExact& g,
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real lat1, real lon1,
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real azi1, real salp1, real calp1,
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unsigned caps);
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GeodesicLineExact(const GeodesicExact& g,
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real lat1, real lon1,
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real azi1, real salp1, real calp1,
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unsigned caps, bool arcmode, real s13_a13);
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enum captype {
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CAP_NONE = GeodesicExact::CAP_NONE,
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CAP_E = GeodesicExact::CAP_E,
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CAP_D = GeodesicExact::CAP_D,
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CAP_H = GeodesicExact::CAP_H,
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CAP_C4 = GeodesicExact::CAP_C4,
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CAP_ALL = GeodesicExact::CAP_ALL,
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CAP_MASK = GeodesicExact::CAP_MASK,
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OUT_ALL = GeodesicExact::OUT_ALL,
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OUT_MASK = GeodesicExact::OUT_MASK,
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};
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public:
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/**
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* Bit masks for what calculations to do. They signify to the
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* GeodesicLineExact::GeodesicLineExact constructor and to
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* GeodesicExact::Line what capabilities should be included in the
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* GeodesicLineExact object. This is merely a duplication of
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* GeodesicExact::mask.
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**********************************************************************/
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enum mask {
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/**
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* No capabilities, no output.
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* @hideinitializer
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**********************************************************************/
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NONE = GeodesicExact::NONE,
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/**
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* Calculate latitude \e lat2. (It's not necessary to include this as a
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* capability to GeodesicLineExact because this is included by default.)
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* @hideinitializer
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**********************************************************************/
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LATITUDE = GeodesicExact::LATITUDE,
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/**
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* Calculate longitude \e lon2.
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* @hideinitializer
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**********************************************************************/
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LONGITUDE = GeodesicExact::LONGITUDE,
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/**
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* Calculate azimuths \e azi1 and \e azi2. (It's not necessary to
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* include this as a capability to GeodesicLineExact because this is
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* included by default.)
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* @hideinitializer
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**********************************************************************/
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AZIMUTH = GeodesicExact::AZIMUTH,
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/**
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* Calculate distance \e s12.
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* @hideinitializer
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**********************************************************************/
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DISTANCE = GeodesicExact::DISTANCE,
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/**
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* Allow distance \e s12 to be used as input in the direct geodesic
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* problem.
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* @hideinitializer
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**********************************************************************/
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DISTANCE_IN = GeodesicExact::DISTANCE_IN,
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/**
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* Calculate reduced length \e m12.
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* @hideinitializer
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**********************************************************************/
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REDUCEDLENGTH = GeodesicExact::REDUCEDLENGTH,
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/**
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* Calculate geodesic scales \e M12 and \e M21.
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* @hideinitializer
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**********************************************************************/
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GEODESICSCALE = GeodesicExact::GEODESICSCALE,
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/**
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* Calculate area \e S12.
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* @hideinitializer
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**********************************************************************/
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AREA = GeodesicExact::AREA,
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/**
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* Unroll \e lon2 in the direct calculation.
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* @hideinitializer
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**********************************************************************/
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LONG_UNROLL = GeodesicExact::LONG_UNROLL,
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/**
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* All capabilities, calculate everything. (LONG_UNROLL is not
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* included in this mask.)
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* @hideinitializer
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**********************************************************************/
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ALL = GeodesicExact::ALL,
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};
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/** \name Constructors
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**********************************************************************/
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///@{
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/**
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* Constructor for a geodesic line staring at latitude \e lat1, longitude
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* \e lon1, and azimuth \e azi1 (all in degrees).
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*
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* @param[in] g A GeodesicExact object used to compute the necessary
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* information about the GeodesicLineExact.
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* @param[in] lat1 latitude of point 1 (degrees).
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* @param[in] lon1 longitude of point 1 (degrees).
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* @param[in] azi1 azimuth at point 1 (degrees).
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* @param[in] caps bitor'ed combination of GeodesicLineExact::mask values
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* specifying the capabilities the GeodesicLineExact object should
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* possess, i.e., which quantities can be returned in calls to
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* GeodesicLine::Position.
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*
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* \e lat1 should be in the range [−90°, 90°].
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*
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* The GeodesicLineExact::mask values are
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* - \e caps |= GeodesicLineExact::LATITUDE for the latitude \e lat2; this
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* is added automatically;
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* - \e caps |= GeodesicLineExact::LONGITUDE for the latitude \e lon2;
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* - \e caps |= GeodesicLineExact::AZIMUTH for the latitude \e azi2; this
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* is added automatically;
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* - \e caps |= GeodesicLineExact::DISTANCE for the distance \e s12;
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* - \e caps |= GeodesicLineExact::REDUCEDLENGTH for the reduced length \e
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m12;
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* - \e caps |= GeodesicLineExact::GEODESICSCALE for the geodesic scales \e
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* M12 and \e M21;
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* - \e caps |= GeodesicLineExact::AREA for the area \e S12;
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* - \e caps |= GeodesicLineExact::DISTANCE_IN permits the length of the
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* geodesic to be given in terms of \e s12; without this capability the
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* length can only be specified in terms of arc length;
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* - \e caps |= GeodesicLineExact::ALL for all of the above.
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* .
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* The default value of \e caps is GeodesicLineExact::ALL.
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*
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* If the point is at a pole, the azimuth is defined by keeping \e lon1
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* fixed, writing \e lat1 = ±(90° − ε), and taking
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* the limit ε → 0+.
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**********************************************************************/
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GeodesicLineExact(const GeodesicExact& g, real lat1, real lon1, real azi1,
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unsigned caps = ALL);
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/**
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* A default constructor. If GeodesicLineExact::Position is called on the
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* resulting object, it returns immediately (without doing any
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* calculations). The object can be set with a call to
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* GeodesicExact::Line. Use Init() to test whether object is still in this
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* uninitialized state.
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**********************************************************************/
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GeodesicLineExact() : _caps(0U) {}
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///@}
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/** \name Position in terms of distance
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**********************************************************************/
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///@{
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/**
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* Compute the position of point 2 which is a distance \e s12 (meters)
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* from point 1.
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*
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* @param[in] s12 distance from point 1 to point 2 (meters); it can be
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* signed.
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* @param[out] lat2 latitude of point 2 (degrees).
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* @param[out] lon2 longitude of point 2 (degrees); requires that the
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* GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::LONGITUDE.
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* @param[out] azi2 (forward) azimuth at point 2 (degrees).
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* @param[out] m12 reduced length of geodesic (meters); requires that the
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* GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::REDUCEDLENGTH.
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* @param[out] M12 geodesic scale of point 2 relative to point 1
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* (dimensionless); requires that the GeodesicLineExact object was
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* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
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* @param[out] M21 geodesic scale of point 1 relative to point 2
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* (dimensionless); requires that the GeodesicLineExact object was
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* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
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* @param[out] S12 area under the geodesic (meters<sup>2</sup>); requires
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* that the GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::AREA.
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* @return \e a12 arc length from point 1 to point 2 (degrees).
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*
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* The values of \e lon2 and \e azi2 returned are in the range
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* [−180°, 180°].
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*
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* The GeodesicLineExact object \e must have been constructed with \e caps
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* |= GeodesicLineExact::DISTANCE_IN; otherwise Math::NaN() is returned and
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* no parameters are set. Requesting a value which the GeodesicLineExact
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* object is not capable of computing is not an error; the corresponding
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* argument will not be altered.
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*
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* The following functions are overloaded versions of
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* GeodesicLineExact::Position which omit some of the output parameters.
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* Note, however, that the arc length is always computed and returned as
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* the function value.
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**********************************************************************/
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Math::real Position(real s12,
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real& lat2, real& lon2, real& azi2,
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real& m12, real& M12, real& M21,
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real& S12) const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE | AZIMUTH |
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REDUCEDLENGTH | GEODESICSCALE | AREA,
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lat2, lon2, azi2, t, m12, M12, M21, S12);
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}
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/**
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* See the documentation for GeodesicLineExact::Position.
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**********************************************************************/
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Math::real Position(real s12, real& lat2, real& lon2) const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE,
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lat2, lon2, t, t, t, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::Position.
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**********************************************************************/
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Math::real Position(real s12, real& lat2, real& lon2,
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real& azi2) const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE | AZIMUTH,
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lat2, lon2, azi2, t, t, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::Position.
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**********************************************************************/
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Math::real Position(real s12, real& lat2, real& lon2,
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real& azi2, real& m12) const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE |
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AZIMUTH | REDUCEDLENGTH,
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lat2, lon2, azi2, t, m12, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::Position.
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**********************************************************************/
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Math::real Position(real s12, real& lat2, real& lon2,
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real& azi2, real& M12, real& M21)
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const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE |
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AZIMUTH | GEODESICSCALE,
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lat2, lon2, azi2, t, t, M12, M21, t);
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}
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/**
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* See the documentation for GeodesicLineExact::Position.
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**********************************************************************/
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Math::real Position(real s12,
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real& lat2, real& lon2, real& azi2,
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real& m12, real& M12, real& M21)
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const {
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real t;
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return GenPosition(false, s12,
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LATITUDE | LONGITUDE | AZIMUTH |
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REDUCEDLENGTH | GEODESICSCALE,
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lat2, lon2, azi2, t, m12, M12, M21, t);
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}
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///@}
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/** \name Position in terms of arc length
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**********************************************************************/
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///@{
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/**
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* Compute the position of point 2 which is an arc length \e a12 (degrees)
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* from point 1.
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*
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* @param[in] a12 arc length from point 1 to point 2 (degrees); it can
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* be signed.
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* @param[out] lat2 latitude of point 2 (degrees).
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* @param[out] lon2 longitude of point 2 (degrees); requires that the
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* GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::LONGITUDE.
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* @param[out] azi2 (forward) azimuth at point 2 (degrees).
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* @param[out] s12 distance from point 1 to point 2 (meters); requires
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* that the GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::DISTANCE.
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* @param[out] m12 reduced length of geodesic (meters); requires that the
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* GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::REDUCEDLENGTH.
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* @param[out] M12 geodesic scale of point 2 relative to point 1
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* (dimensionless); requires that the GeodesicLineExact object was
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* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
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* @param[out] M21 geodesic scale of point 1 relative to point 2
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* (dimensionless); requires that the GeodesicLineExact object was
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* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
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* @param[out] S12 area under the geodesic (meters<sup>2</sup>); requires
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* that the GeodesicLineExact object was constructed with \e caps |=
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* GeodesicLineExact::AREA.
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*
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* The values of \e lon2 and \e azi2 returned are in the range
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* [−180°, 180°].
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*
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* Requesting a value which the GeodesicLineExact object is not capable of
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* computing is not an error; the corresponding argument will not be
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* altered.
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*
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* The following functions are overloaded versions of
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* GeodesicLineExact::ArcPosition which omit some of the output parameters.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2, real& azi2,
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real& s12, real& m12, real& M12, real& M21,
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real& S12) const {
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH | DISTANCE |
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REDUCEDLENGTH | GEODESICSCALE | AREA,
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lat2, lon2, azi2, s12, m12, M12, M21, S12);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2)
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const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE,
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lat2, lon2, t, t, t, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12,
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real& lat2, real& lon2, real& azi2)
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const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH,
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lat2, lon2, azi2, t, t, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2, real& azi2,
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real& s12) const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH | DISTANCE,
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lat2, lon2, azi2, s12, t, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2, real& azi2,
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real& s12, real& m12) const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH |
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DISTANCE | REDUCEDLENGTH,
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lat2, lon2, azi2, s12, m12, t, t, t);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2, real& azi2,
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real& s12, real& M12, real& M21)
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const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH |
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DISTANCE | GEODESICSCALE,
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lat2, lon2, azi2, s12, t, M12, M21, t);
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}
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/**
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* See the documentation for GeodesicLineExact::ArcPosition.
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**********************************************************************/
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void ArcPosition(real a12, real& lat2, real& lon2, real& azi2,
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real& s12, real& m12, real& M12, real& M21)
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const {
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real t;
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GenPosition(true, a12,
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LATITUDE | LONGITUDE | AZIMUTH |
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DISTANCE | REDUCEDLENGTH | GEODESICSCALE,
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lat2, lon2, azi2, s12, m12, M12, M21, t);
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}
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///@}
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/** \name The general position function.
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**********************************************************************/
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///@{
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/**
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* The general position function. GeodesicLineExact::Position and
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* GeodesicLineExact::ArcPosition are defined in terms of this function.
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*
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* @param[in] arcmode boolean flag determining the meaning of the second
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* parameter; if \e arcmode is false, then the GeodesicLineExact object
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* must have been constructed with \e caps |=
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* GeodesicLineExact::DISTANCE_IN.
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* @param[in] s12_a12 if \e arcmode is false, this is the distance between
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* point 1 and point 2 (meters); otherwise it is the arc length between
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* point 1 and point 2 (degrees); it can be signed.
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* @param[in] outmask a bitor'ed combination of GeodesicLineExact::mask
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* values specifying which of the following parameters should be set.
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* @param[out] lat2 latitude of point 2 (degrees).
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|
* @param[out] lon2 longitude of point 2 (degrees); requires that the
|
|
* GeodesicLineExact object was constructed with \e caps |=
|
|
* GeodesicLineExact::LONGITUDE.
|
|
* @param[out] azi2 (forward) azimuth at point 2 (degrees).
|
|
* @param[out] s12 distance from point 1 to point 2 (meters); requires
|
|
* that the GeodesicLineExact object was constructed with \e caps |=
|
|
* GeodesicLineExact::DISTANCE.
|
|
* @param[out] m12 reduced length of geodesic (meters); requires that the
|
|
* GeodesicLineExact object was constructed with \e caps |=
|
|
* GeodesicLineExact::REDUCEDLENGTH.
|
|
* @param[out] M12 geodesic scale of point 2 relative to point 1
|
|
* (dimensionless); requires that the GeodesicLineExact object was
|
|
* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
|
|
* @param[out] M21 geodesic scale of point 1 relative to point 2
|
|
* (dimensionless); requires that the GeodesicLineExact object was
|
|
* constructed with \e caps |= GeodesicLineExact::GEODESICSCALE.
|
|
* @param[out] S12 area under the geodesic (meters<sup>2</sup>); requires
|
|
* that the GeodesicLineExact object was constructed with \e caps |=
|
|
* GeodesicLineExact::AREA.
|
|
* @return \e a12 arc length from point 1 to point 2 (degrees).
|
|
*
|
|
* The GeodesicLineExact::mask values possible for \e outmask are
|
|
* - \e outmask |= GeodesicLineExact::LATITUDE for the latitude \e lat2;
|
|
* - \e outmask |= GeodesicLineExact::LONGITUDE for the latitude \e lon2;
|
|
* - \e outmask |= GeodesicLineExact::AZIMUTH for the latitude \e azi2;
|
|
* - \e outmask |= GeodesicLineExact::DISTANCE for the distance \e s12;
|
|
* - \e outmask |= GeodesicLineExact::REDUCEDLENGTH for the reduced length
|
|
* \e m12;
|
|
* - \e outmask |= GeodesicLineExact::GEODESICSCALE for the geodesic scales
|
|
* \e M12 and \e M21;
|
|
* - \e outmask |= GeodesicLineExact::AREA for the area \e S12;
|
|
* - \e outmask |= GeodesicLineExact::ALL for all of the above;
|
|
* - \e outmask |= GeodesicLineExact::LONG_UNROLL to unroll \e lon2 instead
|
|
* of wrapping it into the range [−180°, 180°].
|
|
* .
|
|
* Requesting a value which the GeodesicLineExact 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 GeodesicLineExact::LONG_UNROLL bit set, the quantity \e lon2
|
|
* − \e lon1 indicates how many times and in what sense the geodesic
|
|
* encircles the ellipsoid.
|
|
**********************************************************************/
|
|
Math::real GenPosition(bool arcmode, real s12_a12, unsigned outmask,
|
|
real& lat2, real& lon2, real& azi2,
|
|
real& s12, real& m12, real& M12, real& M21,
|
|
real& S12) const;
|
|
///@}
|
|
|
|
/** \name Setting point 3
|
|
**********************************************************************/
|
|
///@{
|
|
|
|
/**
|
|
* Specify position of point 3 in terms of distance.
|
|
*
|
|
* @param[in] s13 the distance from point 1 to point 3 (meters); it
|
|
* can be negative.
|
|
*
|
|
* This is only useful if the GeodesicLineExact object has been constructed
|
|
* with \e caps |= GeodesicLineExact::DISTANCE_IN.
|
|
**********************************************************************/
|
|
void SetDistance(real s13);
|
|
|
|
/**
|
|
* Specify position of point 3 in terms of arc length.
|
|
*
|
|
* @param[in] a13 the arc length from point 1 to point 3 (degrees); it
|
|
* can be negative.
|
|
*
|
|
* The distance \e s13 is only set if the GeodesicLineExact object has been
|
|
* constructed with \e caps |= GeodesicLineExact::DISTANCE.
|
|
**********************************************************************/
|
|
void SetArc(real a13);
|
|
|
|
/**
|
|
* Specify position of point 3 in terms of either distance or arc length.
|
|
*
|
|
* @param[in] arcmode boolean flag determining the meaning of the second
|
|
* parameter; if \e arcmode is false, then the GeodesicLineExact object
|
|
* must have been constructed with \e caps |=
|
|
* GeodesicLineExact::DISTANCE_IN.
|
|
* @param[in] s13_a13 if \e 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.
|
|
**********************************************************************/
|
|
void GenSetDistance(bool arcmode, real s13_a13);
|
|
|
|
/** \name Inspector functions
|
|
**********************************************************************/
|
|
///@{
|
|
|
|
/**
|
|
* @return true if the object has been initialized.
|
|
**********************************************************************/
|
|
bool Init() const { return _caps != 0U; }
|
|
|
|
/**
|
|
* @return \e lat1 the latitude of point 1 (degrees).
|
|
**********************************************************************/
|
|
Math::real Latitude() const
|
|
{ return Init() ? _lat1 : Math::NaN(); }
|
|
|
|
/**
|
|
* @return \e lon1 the longitude of point 1 (degrees).
|
|
**********************************************************************/
|
|
Math::real Longitude() const
|
|
{ return Init() ? _lon1 : Math::NaN(); }
|
|
|
|
/**
|
|
* @return \e azi1 the azimuth (degrees) of the geodesic line at point 1.
|
|
**********************************************************************/
|
|
Math::real Azimuth() const
|
|
{ return Init() ? _azi1 : Math::NaN(); }
|
|
|
|
/**
|
|
* The sine and cosine of \e azi1.
|
|
*
|
|
* @param[out] sazi1 the sine of \e azi1.
|
|
* @param[out] cazi1 the cosine of \e azi1.
|
|
**********************************************************************/
|
|
void Azimuth(real& sazi1, real& cazi1) const
|
|
{ if (Init()) { sazi1 = _salp1; cazi1 = _calp1; } }
|
|
|
|
/**
|
|
* @return \e azi0 the azimuth (degrees) of the geodesic line as it crosses
|
|
* the equator in a northward direction.
|
|
*
|
|
* The result lies in [−90°, 90°].
|
|
**********************************************************************/
|
|
Math::real EquatorialAzimuth() const
|
|
{ return Init() ? Math::atan2d(_salp0, _calp0) : Math::NaN(); }
|
|
|
|
/**
|
|
* The sine and cosine of \e azi0.
|
|
*
|
|
* @param[out] sazi0 the sine of \e azi0.
|
|
* @param[out] cazi0 the cosine of \e azi0.
|
|
**********************************************************************/
|
|
void EquatorialAzimuth(real& sazi0, real& cazi0) const
|
|
{ if (Init()) { sazi0 = _salp0; cazi0 = _calp0; } }
|
|
|
|
/**
|
|
* @return \e a1 the arc length (degrees) between the northward equatorial
|
|
* crossing and point 1.
|
|
*
|
|
* The result lies in (−180°, 180°].
|
|
**********************************************************************/
|
|
Math::real EquatorialArc() const {
|
|
using std::atan2;
|
|
return Init() ? atan2(_ssig1, _csig1) / Math::degree() : Math::NaN();
|
|
}
|
|
|
|
/**
|
|
* @return \e a the equatorial radius of the ellipsoid (meters). This is
|
|
* the value inherited from the GeodesicExact object used in the
|
|
* constructor.
|
|
**********************************************************************/
|
|
Math::real EquatorialRadius() const
|
|
{ return Init() ? _a : Math::NaN(); }
|
|
|
|
/**
|
|
* @return \e f the flattening of the ellipsoid. This is the value
|
|
* inherited from the GeodesicExact object used in the constructor.
|
|
**********************************************************************/
|
|
Math::real Flattening() const
|
|
{ return Init() ? _f : Math::NaN(); }
|
|
|
|
/**
|
|
* @return \e caps the computational capabilities that this object was
|
|
* constructed with. LATITUDE and AZIMUTH are always included.
|
|
**********************************************************************/
|
|
unsigned Capabilities() const { return _caps; }
|
|
|
|
/**
|
|
* Test what capabilities are available.
|
|
*
|
|
* @param[in] testcaps a set of bitor'ed GeodesicLineExact::mask values.
|
|
* @return true if the GeodesicLineExact object has all these capabilities.
|
|
**********************************************************************/
|
|
bool Capabilities(unsigned testcaps) const {
|
|
testcaps &= OUT_ALL;
|
|
return (_caps & testcaps) == testcaps;
|
|
}
|
|
|
|
/**
|
|
* The distance or arc length to point 3.
|
|
*
|
|
* @param[in] arcmode boolean flag determining the meaning of returned
|
|
* value.
|
|
* @return \e s13 if \e arcmode is false; \e a13 if \e arcmode is true.
|
|
**********************************************************************/
|
|
Math::real GenDistance(bool arcmode) const
|
|
{ return Init() ? (arcmode ? _a13 : _s13) : Math::NaN(); }
|
|
|
|
/**
|
|
* @return \e s13, the distance to point 3 (meters).
|
|
**********************************************************************/
|
|
Math::real Distance() const { return GenDistance(false); }
|
|
|
|
/**
|
|
* @return \e a13, the arc length to point 3 (degrees).
|
|
**********************************************************************/
|
|
Math::real Arc() const { return GenDistance(true); }
|
|
|
|
/**
|
|
* \deprecated An old name for EquatorialRadius().
|
|
**********************************************************************/
|
|
GEOGRAPHICLIB_DEPRECATED("Use EquatorialRadius()")
|
|
Math::real MajorRadius() const { return EquatorialRadius(); }
|
|
///@}
|
|
|
|
};
|
|
|
|
} // namespace GeographicLib
|
|
|
|
#endif // GEOGRAPHICLIB_GEODESICLINEEXACT_HPP
|