1 // Boost.Geometry - gis-projections (based on PROJ4)
3 // Copyright (c) 2008-2015 Barend Gehrels, Amsterdam, the Netherlands.
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.
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)
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
18 // Last updated version of proj: 5.0.0
20 // Original copyright notice:
22 // Permission is hereby granted, free of charge, to any person obtaining a
23 // copy of this software and associated documentation files (the "Software"),
24 // to deal in the Software without restriction, including without limitation
25 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
26 // and/or sell copies of the Software, and to permit persons to whom the
27 // Software is furnished to do so, subject to the following conditions:
29 // The above copyright notice and this permission notice shall be included
30 // in all copies or substantial portions of the Software.
32 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
33 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
34 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
35 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
36 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
37 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
38 // DEALINGS IN THE SOFTWARE.
40 #ifndef BOOST_GEOMETRY_PROJECTIONS_NELL_H_HPP
41 #define BOOST_GEOMETRY_PROJECTIONS_NELL_H_HPP
43 #include <boost/geometry/util/math.hpp>
45 #include <boost/geometry/srs/projections/impl/base_static.hpp>
46 #include <boost/geometry/srs/projections/impl/base_dynamic.hpp>
47 #include <boost/geometry/srs/projections/impl/projects.hpp>
48 #include <boost/geometry/srs/projections/impl/factory_entry.hpp>
50 namespace boost { namespace geometry
55 #ifndef DOXYGEN_NO_DETAIL
56 namespace detail { namespace nell_h
59 static const int n_iter = 9;
60 static const double epsilon = 1e-7;
62 template <typename T, typename Parameters>
63 struct base_nell_h_spheroid
65 // FORWARD(s_forward) spheroid
66 // Project coordinates from geographic (lon, lat) to cartesian (x, y)
67 inline void fwd(Parameters const& , T const& lp_lon, T const& lp_lat, T& xy_x, T& xy_y) const
69 xy_x = 0.5 * lp_lon * (1. + cos(lp_lat));
70 xy_y = 2.0 * (lp_lat - tan(0.5 *lp_lat));
73 // INVERSE(s_inverse) spheroid
74 // Project coordinates from cartesian (x, y) to geographic (lon, lat)
75 inline void inv(Parameters const& , T const& xy_x, T const& xy_y, T& lp_lon, T& lp_lat) const
77 static const T half_pi = detail::half_pi<T>();
83 for (i = n_iter; i ; --i) {
84 c = cos(0.5 * lp_lat);
85 lp_lat -= V = (lp_lat - tan(lp_lat/2) - p)/(1. - 0.5/(c*c));
86 if (fabs(V) < epsilon)
90 lp_lat = p < 0. ? -half_pi : half_pi;
93 lp_lon = 2. * xy_x / (1. + cos(lp_lat));
96 static inline std::string get_name()
98 return "nell_h_spheroid";
104 template <typename Parameters>
105 inline void setup_nell_h(Parameters& par)
110 }} // namespace detail::nell_h
114 \brief Nell-Hammer projection
116 \tparam Geographic latlong point type
117 \tparam Cartesian xy point type
118 \tparam Parameters parameter type
119 \par Projection characteristics
123 \image html ex_nell_h.gif
125 template <typename T, typename Parameters>
126 struct nell_h_spheroid : public detail::nell_h::base_nell_h_spheroid<T, Parameters>
128 template <typename Params>
129 inline nell_h_spheroid(Params const& , Parameters & par)
131 detail::nell_h::setup_nell_h(par);
135 #ifndef DOXYGEN_NO_DETAIL
140 BOOST_GEOMETRY_PROJECTIONS_DETAIL_STATIC_PROJECTION_FI(srs::spar::proj_nell_h, nell_h_spheroid)
143 BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_ENTRY_FI(nell_h_entry, nell_h_spheroid)
145 BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_BEGIN(nell_h_init)
147 BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_ENTRY(nell_h, nell_h_entry)
150 } // namespace detail
153 } // namespace projections
155 }} // namespace boost::geometry
157 #endif // BOOST_GEOMETRY_PROJECTIONS_NELL_H_HPP