/usr/include/GeographicLib/PolarStereographic.hpp is in libgeographic-dev 1.49-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 | /**
* \file PolarStereographic.hpp
* \brief Header for GeographicLib::PolarStereographic class
*
* Copyright (c) Charles Karney (2008-2016) <charles@karney.com> and licensed
* under the MIT/X11 License. For more information, see
* https://geographiclib.sourceforge.io/
**********************************************************************/
#if !defined(GEOGRAPHICLIB_POLARSTEREOGRAPHIC_HPP)
#define GEOGRAPHICLIB_POLARSTEREOGRAPHIC_HPP 1
#include <GeographicLib/Constants.hpp>
namespace GeographicLib {
/**
* \brief Polar stereographic projection
*
* Implementation taken from the report,
* - J. P. Snyder,
* <a href="http://pubs.er.usgs.gov/usgspubs/pp/pp1395"> Map Projections: A
* Working Manual</a>, USGS Professional Paper 1395 (1987),
* pp. 160--163.
*
* This is a straightforward implementation of the equations in Snyder except
* that Newton's method is used to invert the projection.
*
* This class also returns the meridian convergence \e gamma and scale \e k.
* The meridian convergence is the bearing of grid north (the \e y axis)
* measured clockwise from true north.
*
* Example of use:
* \include example-PolarStereographic.cpp
**********************************************************************/
class GEOGRAPHICLIB_EXPORT PolarStereographic {
private:
typedef Math::real real;
real _a, _f, _e2, _es, _e2m, _c;
real _k0;
public:
/**
* Constructor for a ellipsoid with
*
* @param[in] a equatorial radius (meters).
* @param[in] f flattening of ellipsoid. Setting \e f = 0 gives a sphere.
* Negative \e f gives a prolate ellipsoid.
* @param[in] k0 central scale factor.
* @exception GeographicErr if \e a, (1 − \e f) \e a, or \e k0 is
* not positive.
**********************************************************************/
PolarStereographic(real a, real f, real k0);
/**
* Set the scale for the projection.
*
* @param[in] lat (degrees) assuming \e northp = true.
* @param[in] k scale at latitude \e lat (default 1).
* @exception GeographicErr \e k is not positive.
* @exception GeographicErr if \e lat is not in (−90°,
* 90°].
**********************************************************************/
void SetScale(real lat, real k = real(1));
/**
* Forward projection, from geographic to polar stereographic.
*
* @param[in] northp the pole which is the center of projection (true means
* north, false means south).
* @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] gamma meridian convergence at point (degrees).
* @param[out] k scale of projection at point.
*
* No false easting or northing is added. \e lat should be in the range
* (−90°, 90°] for \e northp = true and in the range
* [−90°, 90°) for \e northp = false.
**********************************************************************/
void Forward(bool northp, real lat, real lon,
real& x, real& y, real& gamma, real& k) const;
/**
* Reverse projection, from polar stereographic to geographic.
*
* @param[in] northp the pole which is the center of projection (true means
* north, false means south).
* @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] gamma meridian convergence at point (degrees).
* @param[out] k scale of projection at point.
*
* No false easting or northing is added. The value of \e lon returned is
* in the range [−180°, 180°].
**********************************************************************/
void Reverse(bool northp, real x, real y,
real& lat, real& lon, real& gamma, real& k) const;
/**
* PolarStereographic::Forward without returning the convergence and scale.
**********************************************************************/
void Forward(bool northp, real lat, real lon,
real& x, real& y) const {
real gamma, k;
Forward(northp, lat, lon, x, y, gamma, k);
}
/**
* PolarStereographic::Reverse without returning the convergence and scale.
**********************************************************************/
void Reverse(bool northp, real x, real y,
real& lat, real& lon) const {
real gamma, k;
Reverse(northp, x, y, lat, lon, gamma, k);
}
/** \name Inspector functions
**********************************************************************/
///@{
/**
* @return \e a the equatorial radius of the ellipsoid (meters). This is
* the value used in the constructor.
**********************************************************************/
Math::real MajorRadius() const { return _a; }
/**
* @return \e f the flattening of the ellipsoid. This is the value used in
* the constructor.
**********************************************************************/
Math::real Flattening() const { return _f; }
/**
* The central scale for the projection. This is the value of \e k0 used
* in the constructor and is the scale at the pole unless overridden by
* PolarStereographic::SetScale.
**********************************************************************/
Math::real CentralScale() const { return _k0; }
///@}
/**
* A global instantiation of PolarStereographic with the WGS84 ellipsoid
* and the UPS scale factor. However, unlike UPS, no false easting or
* northing is added.
**********************************************************************/
static const PolarStereographic& UPS();
};
} // namespace GeographicLib
#endif // GEOGRAPHICLIB_POLARSTEREOGRAPHIC_HPP
|