boost/geometry/srs/projections/proj/airy.hpp

   1 // Boost.Geometry - gis-projections (based on PROJ4)
   2
   3 // Copyright (c) 2008-2015 Barend Gehrels, Amsterdam, the Netherlands.
   4
   5 // This file was modified by Oracle on 2017, 2018, 2019.
   6 // Modifications copyright (c) 2017-2019, Oracle and/or its affiliates.
   7 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle.
   8
   9 // Use, modification and distribution is subject to the Boost Software License,
  10 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  11 // http://www.boost.org/LICENSE_1_0.txt)
  12
  13 // This file is converted from PROJ4, http://trac.osgeo.org/proj
  14 // PROJ4 is originally written by Gerald Evenden (then of the USGS)
  15 // PROJ4 is maintained by Frank Warmerdam
  16 // PROJ4 is converted to Boost.Geometry by Barend Gehrels
  17
  18 // Last updated version of proj: 5.0.0
  19
  20 // Original copyright notice:
  21
  22 // Purpose:  Implementation of the airy (Airy) projection.
  23 // Author:   Gerald Evenden (1995)
  24 //           Thomas Knudsen (2016) - revise/add regression tests
  25 // Copyright (c) 1995, Gerald Evenden
  26
  27 // Permission is hereby granted, free of charge, to any person obtaining a
  28 // copy of this software and associated documentation files (the "Software"),
  29 // to deal in the Software without restriction, including without limitation
  30 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  31 // and/or sell copies of the Software, and to permit persons to whom the
  32 // Software is furnished to do so, subject to the following conditions:
  33
  34 // The above copyright notice and this permission notice shall be included
  35 // in all copies or substantial portions of the Software.
  36
  37 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  38 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  39 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  40 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  41 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  42 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  43 // DEALINGS IN THE SOFTWARE.
  44
  45 #ifndef BOOST_GEOMETRY_PROJECTIONS_AIRY_HPP
  46 #define BOOST_GEOMETRY_PROJECTIONS_AIRY_HPP
  47
  48 #include <boost/geometry/srs/projections/impl/base_static.hpp>
  49 #include <boost/geometry/srs/projections/impl/base_dynamic.hpp>
  50 #include <boost/geometry/srs/projections/impl/factory_entry.hpp>
  51 #include <boost/geometry/srs/projections/impl/pj_param.hpp>
  52 #include <boost/geometry/srs/projections/impl/projects.hpp>
  53
  54 #include <boost/geometry/util/math.hpp>
  55
  56 namespace boost { namespace geometry
  57 {
  58
  59 namespace projections
  60 {
  61     #ifndef DOXYGEN_NO_DETAIL
  62     namespace detail { namespace airy
  63     {
  64
  65             static const double epsilon = 1.e-10;
  66             enum mode_type {
  67                 n_pole = 0,
  68                 s_pole = 1,
  69                 equit  = 2,
  70                 obliq  = 3
  71             };
  72
  73             template <typename T>
  74             struct par_airy
  75             {
  76                 T    p_halfpi;
  77                 T    sinph0;
  78                 T    cosph0;
  79                 T    Cb;
  80                 mode_type mode;
  81                 bool no_cut;    /* do not cut at hemisphere limit */
  82             };
  83
  84             template <typename T, typename Parameters>
  85             struct base_airy_spheroid
  86             {
  87                 par_airy<T> m_proj_parm;
  88
  89                 // FORWARD(s_forward)  spheroid
  90                 // Project coordinates from geographic (lon, lat) to cartesian (x, y)
  91                 inline void fwd(Parameters const& , T const& lp_lon, T lp_lat, T& xy_x, T& xy_y) const
  92                 {
  93                     static const T half_pi = detail::half_pi<T>();
  94
  95                     T  sinlam, coslam, cosphi, sinphi, t, s, Krho, cosz;
  96
  97                     sinlam = sin(lp_lon);
  98                     coslam = cos(lp_lon);
  99                     switch (this->m_proj_parm.mode) {
 100                     case equit:
 101                     case obliq:
 102                         sinphi = sin(lp_lat);
 103                         cosphi = cos(lp_lat);
 104                         cosz = cosphi * coslam;
 105                         if (this->m_proj_parm.mode == obliq)
 106                             cosz = this->m_proj_parm.sinph0 * sinphi + this->m_proj_parm.cosph0 * cosz;
 107                         if (!this->m_proj_parm.no_cut && cosz < -epsilon) {
 108                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
 109                         }
 110                         if (fabs(s = 1. - cosz) > epsilon) {
 111                             t = 0.5 * (1. + cosz);
 112                             Krho = -log(t)/s - this->m_proj_parm.Cb / t;
 113                         } else
 114                             Krho = 0.5 - this->m_proj_parm.Cb;
 115                         xy_x = Krho * cosphi * sinlam;
 116                         if (this->m_proj_parm.mode == obliq)
 117                             xy_y = Krho * (this->m_proj_parm.cosph0 * sinphi -
 118                                 this->m_proj_parm.sinph0 * cosphi * coslam);
 119                         else
 120                             xy_y = Krho * sinphi;
 121                         break;
 122                     case s_pole:
 123                     case n_pole:
 124                         lp_lat = fabs(this->m_proj_parm.p_halfpi - lp_lat);
 125                         if (!this->m_proj_parm.no_cut && (lp_lat - epsilon) > half_pi)
 126                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
 127                         if ((lp_lat *= 0.5) > epsilon) {
 128                             t = tan(lp_lat);
 129                             Krho = -2.*(log(cos(lp_lat)) / t + t * this->m_proj_parm.Cb);
 130                             xy_x = Krho * sinlam;
 131                             xy_y = Krho * coslam;
 132                             if (this->m_proj_parm.mode == n_pole)
 133                                 xy_y = -xy_y;
 134                         } else
 135                             xy_x = xy_y = 0.;
 136                     }
 137                 }
 138
 139                 static inline std::string get_name()
 140                 {
 141                     return "airy_spheroid";
 142                 }
 143
 144             };
 145
 146             // Airy
 147             template <typename Params, typename Parameters, typename T>
 148             inline void setup_airy(Params const& params, Parameters& par, par_airy<T>& proj_parm)
 149             {
 150                 static const T half_pi = detail::half_pi<T>();
 151
 152                 T beta;
 153
 154                 proj_parm.no_cut = pj_get_param_b<srs::spar::no_cut>(params, "no_cut", srs::dpar::no_cut);
 155                 beta = 0.5 * (half_pi - pj_get_param_r<T, srs::spar::lat_b>(params, "lat_b", srs::dpar::lat_b));
 156                 if (fabs(beta) < epsilon)
 157                     proj_parm.Cb = -0.5;
 158                 else {
 159                     proj_parm.Cb = 1./tan(beta);
 160                     proj_parm.Cb *= proj_parm.Cb * log(cos(beta));
 161                 }
 162
 163                 if (fabs(fabs(par.phi0) - half_pi) < epsilon)
 164                     if (par.phi0 < 0.) {
 165                         proj_parm.p_halfpi = -half_pi;
 166                         proj_parm.mode = s_pole;
 167                     } else {
 168                         proj_parm.p_halfpi =  half_pi;
 169                         proj_parm.mode = n_pole;
 170                     }
 171                 else {
 172                     if (fabs(par.phi0) < epsilon)
 173                         proj_parm.mode = equit;
 174                     else {
 175                         proj_parm.mode = obliq;
 176                         proj_parm.sinph0 = sin(par.phi0);
 177                         proj_parm.cosph0 = cos(par.phi0);
 178                     }
 179                 }
 180                 par.es = 0.;
 181             }
 182
 183     }} // namespace detail::airy
 184     #endif // doxygen
 185
 186     /*!
 187         \brief Airy projection
 188         \ingroup projections
 189         \tparam Geographic latlong point type
 190         \tparam Cartesian xy point type
 191         \tparam Parameters parameter type
 192         \par Projection characteristics
 193          - Miscellaneous
 194          - Spheroid
 195          - no inverse
 196         \par Projection parameters
 197          - no_cut: Do not cut at hemisphere limit (boolean)
 198          - lat_b (degrees)
 199         \par Example
 200         \image html ex_airy.gif
 201     */
 202     template <typename T, typename Parameters>
 203     struct airy_spheroid : public detail::airy::base_airy_spheroid<T, Parameters>
 204     {
 205         template <typename Params>
 206         inline airy_spheroid(Params const& params, Parameters & par)
 207         {
 208             detail::airy::setup_airy(params, par, this->m_proj_parm);
 209         }
 210     };
 211
 212     #ifndef DOXYGEN_NO_DETAIL
 213     namespace detail
 214     {
 215
 216         // Static projection
 217         BOOST_GEOMETRY_PROJECTIONS_DETAIL_STATIC_PROJECTION_F(srs::spar::proj_airy, airy_spheroid)
 218
 219         // Factory entry(s)
 220         BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_ENTRY_F(airy_entry, airy_spheroid)
 221
 222         BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_BEGIN(airy_init)
 223         {
 224             BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_ENTRY(airy, airy_entry)
 225         }
 226
 227     } // namespace detail
 228     #endif // doxygen
 229
 230 } // namespace projections
 231
 232 }} // namespace boost::geometry
 233
 234 #endif // BOOST_GEOMETRY_PROJECTIONS_AIRY_HPP
 235