projections/proj/ortho.hpp

0001 // Boost.Geometry - gis-projections (based on PROJ4)
0002
0003 // Copyright (c) 2008-2015 Barend Gehrels, Amsterdam, the Netherlands.
0004
0005 // This file was modified by Oracle on 2017, 2018, 2019.
0006 // Modifications copyright (c) 2017-2019, Oracle and/or its affiliates.
0007 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle.
0008
0009 // Use, modification and distribution is subject to the Boost Software License,
0010 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
0011 // http://www.boost.org/LICENSE_1_0.txt)
0012
0013 // This file is converted from PROJ4, http://trac.osgeo.org/proj
0014 // PROJ4 is originally written by Gerald Evenden (then of the USGS)
0015 // PROJ4 is maintained by Frank Warmerdam
0016 // PROJ4 is converted to Boost.Geometry by Barend Gehrels
0017
0018 // Last updated version of proj: 5.0.0
0019
0020 // Original copyright notice:
0021
0022 // Permission is hereby granted, free of charge, to any person obtaining a
0023 // copy of this software and associated documentation files (the "Software"),
0024 // to deal in the Software without restriction, including without limitation
0025 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
0026 // and/or sell copies of the Software, and to permit persons to whom the
0027 // Software is furnished to do so, subject to the following conditions:
0028
0029 // The above copyright notice and this permission notice shall be included
0030 // in all copies or substantial portions of the Software.
0031
0032 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
0033 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0034 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
0035 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
0036 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
0037 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
0038 // DEALINGS IN THE SOFTWARE.
0039
0040 #ifndef BOOST_GEOMETRY_PROJECTIONS_ORTHO_HPP
0041 #define BOOST_GEOMETRY_PROJECTIONS_ORTHO_HPP
0042
0043 #include <boost/config.hpp>
0044 #include <boost/geometry/util/math.hpp>
0045 #include <boost/math/special_functions/hypot.hpp>
0046
0047 #include <boost/geometry/srs/projections/impl/base_static.hpp>
0048 #include <boost/geometry/srs/projections/impl/base_dynamic.hpp>
0049 #include <boost/geometry/srs/projections/impl/projects.hpp>
0050 #include <boost/geometry/srs/projections/impl/factory_entry.hpp>
0051
0052 namespace boost { namespace geometry
0053 {
0054
0055 namespace projections
0056 {
0057     #ifndef DOXYGEN_NO_DETAIL
0058     namespace detail { namespace ortho
0059     {
0060
0061             enum mode_type {
0062                 n_pole = 0,
0063                 s_pole = 1,
0064                 equit  = 2,
0065                 obliq  = 3
0066             };
0067
0068             template <typename T>
0069             struct par_ortho
0070             {
0071                 T   sinph0;
0072                 T   cosph0;
0073                 mode_type mode;
0074             };
0075
0076             static const double epsilon10 = 1.e-10;
0077
0078             template <typename T, typename Parameters>
0079             struct base_ortho_spheroid
0080             {
0081                 par_ortho<T> m_proj_parm;
0082
0083                 // FORWARD(s_forward)  spheroid
0084                 // Project coordinates from geographic (lon, lat) to cartesian (x, y)
0085                 inline void fwd(Parameters const& par, T const& lp_lon, T const& lp_lat, T& xy_x, T& xy_y) const
0086                 {
0087                     static const T half_pi = detail::half_pi<T>();
0088
0089                     T coslam, cosphi, sinphi;
0090
0091                     cosphi = cos(lp_lat);
0092                     coslam = cos(lp_lon);
0093                     switch (this->m_proj_parm.mode) {
0094                     case equit:
0095                         if (cosphi * coslam < - epsilon10) {
0096                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
0097                         }
0098                         xy_y = sin(lp_lat);
0099                         break;
0100                     case obliq:
0101                         if (this->m_proj_parm.sinph0 * (sinphi = sin(lp_lat)) +
0102                            this->m_proj_parm.cosph0 * cosphi * coslam < - epsilon10) {
0103                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
0104                         }
0105                         xy_y = this->m_proj_parm.cosph0 * sinphi - this->m_proj_parm.sinph0 * cosphi * coslam;
0106                         break;
0107                     case n_pole:
0108                         coslam = - coslam;
0109                         BOOST_FALLTHROUGH;
0110                     case s_pole:
0111                         if (fabs(lp_lat - par.phi0) - epsilon10 > half_pi) {
0112                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
0113                         }
0114                         xy_y = cosphi * coslam;
0115                         break;
0116                     }
0117                     xy_x = cosphi * sin(lp_lon);
0118                 }
0119
0120                 // INVERSE(s_inverse)  spheroid
0121                 // Project coordinates from cartesian (x, y) to geographic (lon, lat)
0122                 inline void inv(Parameters const& par, T xy_x, T xy_y, T& lp_lon, T& lp_lat) const
0123                 {
0124                     static const T half_pi = detail::half_pi<T>();
0125
0126                     T rh, cosc, sinc;
0127
0128                     if ((sinc = (rh = boost::math::hypot(xy_x, xy_y))) > 1.) {
0129                         if ((sinc - 1.) > epsilon10) {
0130                             BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
0131                         }
0132                         sinc = 1.;
0133                     }
0134                     cosc = sqrt(1. - sinc * sinc); /* in this range OK */
0135                     if (fabs(rh) <= epsilon10) {
0136                         lp_lat = par.phi0;
0137                         lp_lon = 0.0;
0138                     } else {
0139                         switch (this->m_proj_parm.mode) {
0140                         case n_pole:
0141                             xy_y = -xy_y;
0142                             lp_lat = acos(sinc);
0143                             break;
0144                         case s_pole:
0145                             lp_lat = - acos(sinc);
0146                             break;
0147                         case equit:
0148                             lp_lat = xy_y * sinc / rh;
0149                             xy_x *= sinc;
0150                             xy_y = cosc * rh;
0151                             goto sinchk;
0152                         case obliq:
0153                             lp_lat = cosc * this->m_proj_parm.sinph0 + xy_y * sinc * this->m_proj_parm.cosph0 /rh;
0154                             xy_y = (cosc - this->m_proj_parm.sinph0 * lp_lat) * rh;
0155                             xy_x *= sinc * this->m_proj_parm.cosph0;
0156                         sinchk:
0157                             if (fabs(lp_lat) >= 1.)
0158                                 lp_lat = lp_lat < 0. ? -half_pi : half_pi;
0159                             else
0160                                 lp_lat = asin(lp_lat);
0161                             break;
0162                         }
0163                         lp_lon = (xy_y == 0. && (this->m_proj_parm.mode == obliq || this->m_proj_parm.mode == equit))
0164                              ? (xy_x == 0. ? 0. : xy_x < 0. ? -half_pi : half_pi)
0165                                            : atan2(xy_x, xy_y);
0166                     }
0167                 }
0168
0169                 static inline std::string get_name()
0170                 {
0171                     return "ortho_spheroid";
0172                 }
0173
0174             };
0175
0176             // Orthographic
0177             template <typename Parameters, typename T>
0178             inline void setup_ortho(Parameters& par, par_ortho<T>& proj_parm)
0179             {
0180                 if (fabs(fabs(par.phi0) - geometry::math::half_pi<T>()) <= epsilon10)
0181                     proj_parm.mode = par.phi0 < 0. ? s_pole : n_pole;
0182                 else if (fabs(par.phi0) > epsilon10) {
0183                     proj_parm.mode = obliq;
0184                     proj_parm.sinph0 = sin(par.phi0);
0185                     proj_parm.cosph0 = cos(par.phi0);
0186                 } else
0187                     proj_parm.mode = equit;
0188                 par.es = 0.;
0189             }
0190
0191     }} // namespace detail::ortho
0192     #endif // doxygen
0193
0194     /*!
0195         \brief Orthographic projection
0196         \ingroup projections
0197         \tparam Geographic latlong point type
0198         \tparam Cartesian xy point type
0199         \tparam Parameters parameter type
0200         \par Projection characteristics
0201          - Azimuthal
0202          - Spheroid
0203         \par Example
0204         \image html ex_ortho.gif
0205     */
0206     template <typename T, typename Parameters>
0207     struct ortho_spheroid : public detail::ortho::base_ortho_spheroid<T, Parameters>
0208     {
0209         template <typename Params>
0210         inline ortho_spheroid(Params const& , Parameters & par)
0211         {
0212             detail::ortho::setup_ortho(par, this->m_proj_parm);
0213         }
0214     };
0215
0216     #ifndef DOXYGEN_NO_DETAIL
0217     namespace detail
0218     {
0219
0220         // Static projection
0221         BOOST_GEOMETRY_PROJECTIONS_DETAIL_STATIC_PROJECTION_FI(srs::spar::proj_ortho, ortho_spheroid)
0222
0223         // Factory entry(s)
0224         BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_ENTRY_FI(ortho_entry, ortho_spheroid)
0225
0226         BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_BEGIN(ortho_init)
0227         {
0228             BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_ENTRY(ortho, ortho_entry)
0229         }
0230
0231     } // namespace detail
0232     #endif // doxygen
0233
0234 } // namespace projections
0235
0236 }} // namespace boost::geometry
0237
0238 #endif // BOOST_GEOMETRY_PROJECTIONS_ORTHO_HPP
0239