1 // Boost.Geometry (aka GGL, Generic Geometry Library)
2 // This file is manually converted from PROJ4
4 // Copyright (c) 2008-2012 Barend Gehrels, Amsterdam, the Netherlands.
6 // This file was modified by Oracle on 2018.
7 // Modifications copyright (c) 2018, Oracle and/or its affiliates.
8 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
10 // Use, modification and distribution is subject to the Boost Software License,
11 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
12 // http://www.boost.org/LICENSE_1_0.txt)
14 // This file is converted from PROJ4, http://trac.osgeo.org/proj
15 // PROJ4 is originally written by Gerald Evenden (then of the USGS)
16 // PROJ4 is maintained by Frank Warmerdam
17 // PROJ4 is converted to Geometry Library by Barend Gehrels (Geodan, Amsterdam)
19 // Original copyright notice:
21 // Permission is hereby granted, free of charge, to any person obtaining a
22 // copy of this software and associated documentation files (the "Software"),
23 // to deal in the Software without restriction, including without limitation
24 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
25 // and/or sell copies of the Software, and to permit persons to whom the
26 // Software is furnished to do so, subject to the following conditions:
28 // The above copyright notice and this permission notice shall be included
29 // in all copies or substantial portions of the Software.
31 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
32 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
33 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
34 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
35 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
36 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
37 // DEALINGS IN THE SOFTWARE.
39 #ifndef BOOST_GEOMETRY_PROJECTIONS_PROJ_MDIST_HPP
40 #define BOOST_GEOMETRY_PROJECTIONS_PROJ_MDIST_HPP
43 #include <boost/geometry/srs/projections/exception.hpp>
44 #include <boost/geometry/srs/projections/impl/pj_strerrno.hpp>
45 #include <boost/geometry/util/math.hpp>
48 namespace boost { namespace geometry { namespace projections
55 static const int static_size = 20;
64 inline bool proj_mdist_ini(T const& es, mdist<T>& b)
66 T numf, numfi, twon1, denf, denfi, ens, t, twon;
68 T E[mdist<T>::static_size];
71 /* generate E(e^2) and its terms E[] */
73 numf = twon1 = denfi = 1.;
77 for (i = 1; i < mdist<T>::static_size ; ++i)
79 numf *= (twon1 * twon1);
80 den = twon * denf * denf * twon1;
88 if (Es == El) /* jump out if no change */
95 /* generate b_n coefficients--note: collapse with prefix ratios */
96 b.b[0] = Es = 1. - Es;
100 for (j = 1; j < i; ++j)
105 b.b[j] = Es * numf / denf;
112 template <typename T>
113 inline T proj_mdist(T const& phi, T const& sphi, T const& cphi, mdist<T> const& b)
120 D = phi * b.E - b.es * sc / sqrt(1. - b.es * sphi2);
122 while (i) sum = b.b[--i] + sphi2 * sum;
123 return(D + sc * sum);
126 template <typename T>
127 inline T proj_inv_mdist(T const& dist, mdist<T> const& b)
129 static const T TOL = 1e-14;
134 i = mdist<T>::static_size;
138 t = 1. - b.es * s * s;
139 phi -= t = (proj_mdist(phi, s, cos(phi), b) - dist) *
141 if (geometry::math::abs(t) < TOL) /* that is no change */
144 /* convergence failed */
145 BOOST_THROW_EXCEPTION( projection_exception(error_non_conv_inv_meri_dist) );
147 } // namespace detail
149 }}} // namespace boost::geometry::projections