146 lines
6.3 KiB
C++
146 lines
6.3 KiB
C++
/**
|
|
* \file AzimuthalEquidistant.hpp
|
|
* \brief Header for GeographicLib::AzimuthalEquidistant class
|
|
*
|
|
* Copyright (c) Charles Karney (2009-2020) <charles@karney.com> and licensed
|
|
* under the MIT/X11 License. For more information, see
|
|
* https://geographiclib.sourceforge.io/
|
|
**********************************************************************/
|
|
|
|
#if !defined(GEOGRAPHICLIB_AZIMUTHALEQUIDISTANT_HPP)
|
|
#define GEOGRAPHICLIB_AZIMUTHALEQUIDISTANT_HPP 1
|
|
|
|
#include <GeographicLib/Geodesic.hpp>
|
|
#include <GeographicLib/Constants.hpp>
|
|
|
|
namespace GeographicLib {
|
|
|
|
/**
|
|
* \brief Azimuthal equidistant projection
|
|
*
|
|
* Azimuthal equidistant projection centered at an arbitrary position on the
|
|
* ellipsoid. For a point in projected space (\e x, \e y), the geodesic
|
|
* distance from the center position is hypot(\e x, \e y) and the azimuth of
|
|
* the geodesic from the center point is atan2(\e x, \e y). The Forward and
|
|
* Reverse methods also return the azimuth \e azi of the geodesic at (\e x,
|
|
* \e y) and reciprocal scale \e rk in the azimuthal direction which,
|
|
* together with the basic properties of the projection, serve to specify
|
|
* completely the local affine transformation between geographic and
|
|
* projected coordinates.
|
|
*
|
|
* The conversions all take place using a Geodesic object (by default
|
|
* Geodesic::WGS84()). For more information on geodesics see \ref geodesic.
|
|
*
|
|
* Example of use:
|
|
* \include example-AzimuthalEquidistant.cpp
|
|
*
|
|
* <a href="GeodesicProj.1.html">GeodesicProj</a> is a command-line utility
|
|
* providing access to the functionality of AzimuthalEquidistant, Gnomonic,
|
|
* and CassiniSoldner.
|
|
**********************************************************************/
|
|
|
|
class GEOGRAPHICLIB_EXPORT AzimuthalEquidistant {
|
|
private:
|
|
typedef Math::real real;
|
|
real eps_;
|
|
Geodesic _earth;
|
|
public:
|
|
|
|
/**
|
|
* Constructor for AzimuthalEquidistant.
|
|
*
|
|
* @param[in] earth the Geodesic object to use for geodesic calculations.
|
|
* By default this uses the WGS84 ellipsoid.
|
|
**********************************************************************/
|
|
explicit AzimuthalEquidistant(const Geodesic& earth = Geodesic::WGS84());
|
|
|
|
/**
|
|
* Forward projection, from geographic to azimuthal equidistant.
|
|
*
|
|
* @param[in] lat0 latitude of center point of projection (degrees).
|
|
* @param[in] lon0 longitude of center point of projection (degrees).
|
|
* @param[in] lat latitude of point (degrees).
|
|
* @param[in] lon longitude of point (degrees).
|
|
* @param[out] x easting of point (meters).
|
|
* @param[out] y northing of point (meters).
|
|
* @param[out] azi azimuth of geodesic at point (degrees).
|
|
* @param[out] rk reciprocal of azimuthal scale at point.
|
|
*
|
|
* \e lat0 and \e lat should be in the range [−90°, 90°].
|
|
* The scale of the projection is 1 in the "radial" direction, \e azi
|
|
* clockwise from true north, and is 1/\e rk in the direction perpendicular
|
|
* to this. A call to Forward followed by a call to Reverse will return
|
|
* the original (\e lat, \e lon) (to within roundoff).
|
|
**********************************************************************/
|
|
void Forward(real lat0, real lon0, real lat, real lon,
|
|
real& x, real& y, real& azi, real& rk) const;
|
|
|
|
/**
|
|
* Reverse projection, from azimuthal equidistant to geographic.
|
|
*
|
|
* @param[in] lat0 latitude of center point of projection (degrees).
|
|
* @param[in] lon0 longitude of center point of projection (degrees).
|
|
* @param[in] x easting of point (meters).
|
|
* @param[in] y northing of point (meters).
|
|
* @param[out] lat latitude of point (degrees).
|
|
* @param[out] lon longitude of point (degrees).
|
|
* @param[out] azi azimuth of geodesic at point (degrees).
|
|
* @param[out] rk reciprocal of azimuthal scale at point.
|
|
*
|
|
* \e lat0 should be in the range [−90°, 90°]. \e lat will
|
|
* be in the range [−90°, 90°] and \e lon will be in the
|
|
* range [−180°, 180°]. The scale of the projection is 1 in
|
|
* the "radial" direction, \e azi clockwise from true north, and is 1/\e rk
|
|
* in the direction perpendicular to this. A call to Reverse followed by a
|
|
* call to Forward will return the original (\e x, \e y) (to roundoff) only
|
|
* if the geodesic to (\e x, \e y) is a shortest path.
|
|
**********************************************************************/
|
|
void Reverse(real lat0, real lon0, real x, real y,
|
|
real& lat, real& lon, real& azi, real& rk) const;
|
|
|
|
/**
|
|
* AzimuthalEquidistant::Forward without returning the azimuth and scale.
|
|
**********************************************************************/
|
|
void Forward(real lat0, real lon0, real lat, real lon,
|
|
real& x, real& y) const {
|
|
real azi, rk;
|
|
Forward(lat0, lon0, lat, lon, x, y, azi, rk);
|
|
}
|
|
|
|
/**
|
|
* AzimuthalEquidistant::Reverse without returning the azimuth and scale.
|
|
**********************************************************************/
|
|
void Reverse(real lat0, real lon0, real x, real y,
|
|
real& lat, real& lon) const {
|
|
real azi, rk;
|
|
Reverse(lat0, lon0, x, y, lat, lon, azi, rk);
|
|
}
|
|
|
|
/** \name Inspector functions
|
|
**********************************************************************/
|
|
///@{
|
|
/**
|
|
* @return \e a the equatorial radius of the ellipsoid (meters). This is
|
|
* the value inherited from the Geodesic object used in the constructor.
|
|
**********************************************************************/
|
|
Math::real EquatorialRadius() const { return _earth.EquatorialRadius(); }
|
|
|
|
/**
|
|
* @return \e f the flattening of the ellipsoid. This is the value
|
|
* inherited from the Geodesic object used in the constructor.
|
|
**********************************************************************/
|
|
Math::real Flattening() const { return _earth.Flattening(); }
|
|
|
|
/**
|
|
* \deprecated An old name for EquatorialRadius().
|
|
**********************************************************************/
|
|
GEOGRAPHICLIB_DEPRECATED("Use EquatorialRadius()")
|
|
Math::real MajorRadius() const { return EquatorialRadius(); }
|
|
///@}
|
|
|
|
};
|
|
|
|
} // namespace GeographicLib
|
|
|
|
#endif // GEOGRAPHICLIB_AZIMUTHALEQUIDISTANT_HPP
|