// Boost.Geometry - gis-projections (based on PROJ4)
// Copyright (c) 2008-2015 Barend Gehrels, Amsterdam, the Netherlands.
// This file was modified by Oracle on 2017, 2018, 2019.
// Modifications copyright (c) 2017-2019, Oracle and/or its affiliates.
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle.
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// This file is converted from PROJ4, http://trac.osgeo.org/proj
// PROJ4 is originally written by Gerald Evenden (then of the USGS)
// PROJ4 is maintained by Frank Warmerdam
// PROJ4 is converted to Boost.Geometry by Barend Gehrels
// Last updated version of proj: 5.0.0
// Original copyright notice:
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
#ifndef BOOST_GEOMETRY_PROJECTIONS_GNOM_HPP
#define BOOST_GEOMETRY_PROJECTIONS_GNOM_HPP
#include <boost/config.hpp>
#include <boost/geometry/util/math.hpp>
#include <boost/math/special_functions/hypot.hpp>
#include <boost/geometry/srs/projections/impl/base_static.hpp>
#include <boost/geometry/srs/projections/impl/base_dynamic.hpp>
#include <boost/geometry/srs/projections/impl/projects.hpp>
#include <boost/geometry/srs/projections/impl/factory_entry.hpp>
namespace boost { namespace geometry
{
namespace projections
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace gnom
{
static const double epsilon10 = 1.e-10;
enum mode_type {
n_pole = 0,
s_pole = 1,
equit = 2,
obliq = 3
};
template <typename T>
struct par_gnom
{
T sinph0;
T cosph0;
mode_type mode;
};
template <typename T, typename Parameters>
struct base_gnom_spheroid
{
par_gnom<T> m_proj_parm;
// FORWARD(s_forward) spheroid
// Project coordinates from geographic (lon, lat) to cartesian (x, y)
inline void fwd(Parameters const& , T const& lp_lon, T const& lp_lat, T& xy_x, T& xy_y) const
{
T coslam, cosphi, sinphi;
sinphi = sin(lp_lat);
cosphi = cos(lp_lat);
coslam = cos(lp_lon);
switch (this->m_proj_parm.mode) {
case equit:
xy_y = cosphi * coslam;
break;
case obliq:
xy_y = this->m_proj_parm.sinph0 * sinphi + this->m_proj_parm.cosph0 * cosphi * coslam;
break;
case s_pole:
xy_y = - sinphi;
break;
case n_pole:
xy_y = sinphi;
break;
}
if (xy_y <= epsilon10) {
BOOST_THROW_EXCEPTION( projection_exception(error_tolerance_condition) );
}
xy_x = (xy_y = 1. / xy_y) * cosphi * sin(lp_lon);
switch (this->m_proj_parm.mode) {
case equit:
xy_y *= sinphi;
break;
case obliq:
xy_y *= this->m_proj_parm.cosph0 * sinphi - this->m_proj_parm.sinph0 * cosphi * coslam;
break;
case n_pole:
coslam = - coslam;
BOOST_FALLTHROUGH;
case s_pole:
xy_y *= cosphi * coslam;
break;
}
}
// INVERSE(s_inverse) spheroid
// Project coordinates from cartesian (x, y) to geographic (lon, lat)
inline void inv(Parameters const& par, T xy_x, T xy_y, T& lp_lon, T& lp_lat) const
{
static const T half_pi = detail::half_pi<T>();
T rh, cosz, sinz;
rh = boost::math::hypot(xy_x, xy_y);
sinz = sin(lp_lat = atan(rh));
cosz = sqrt(1. - sinz * sinz);
if (fabs(rh) <= epsilon10) {
lp_lat = par.phi0;
lp_lon = 0.;
} else {
switch (this->m_proj_parm.mode) {
case obliq:
lp_lat = cosz * this->m_proj_parm.sinph0 + xy_y * sinz * this->m_proj_parm.cosph0 / rh;
if (fabs(lp_lat) >= 1.)
lp_lat = lp_lat > 0. ? half_pi : -half_pi;
else
lp_lat = asin(lp_lat);
xy_y = (cosz - this->m_proj_parm.sinph0 * sin(lp_lat)) * rh;
xy_x *= sinz * this->m_proj_parm.cosph0;
break;
case equit:
lp_lat = xy_y * sinz / rh;
if (fabs(lp_lat) >= 1.)
lp_lat = lp_lat > 0. ? half_pi : -half_pi;
else
lp_lat = asin(lp_lat);
xy_y = cosz * rh;
xy_x *= sinz;
break;
case s_pole:
lp_lat -= half_pi;
break;
case n_pole:
lp_lat = half_pi - lp_lat;
xy_y = -xy_y;
break;
}
lp_lon = atan2(xy_x, xy_y);
}
}
static inline std::string get_name()
{
return "gnom_spheroid";
}
};
// Gnomonic
template <typename Parameters, typename T>
inline void setup_gnom(Parameters& par, par_gnom<T>& proj_parm)
{
static const T half_pi = detail::half_pi<T>();
if (fabs(fabs(par.phi0) - half_pi) < epsilon10) {
proj_parm.mode = par.phi0 < 0. ? s_pole : n_pole;
} else if (fabs(par.phi0) < epsilon10) {
proj_parm.mode = equit;
} else {
proj_parm.mode = obliq;
proj_parm.sinph0 = sin(par.phi0);
proj_parm.cosph0 = cos(par.phi0);
}
par.es = 0.;
}
}} // namespace detail::gnom
#endif // doxygen
/*!
\brief Gnomonic projection
\ingroup projections
\tparam Geographic latlong point type
\tparam Cartesian xy point type
\tparam Parameters parameter type
\par Projection characteristics
- Azimuthal
- Spheroid
\par Example
\image html ex_gnom.gif
*/
template <typename T, typename Parameters>
struct gnom_spheroid : public detail::gnom::base_gnom_spheroid<T, Parameters>
{
template <typename Params>
inline gnom_spheroid(Params const& , Parameters & par)
{
detail::gnom::setup_gnom(par, this->m_proj_parm);
}
};
#ifndef DOXYGEN_NO_DETAIL
namespace detail
{
// Static projection
BOOST_GEOMETRY_PROJECTIONS_DETAIL_STATIC_PROJECTION_FI(srs::spar::proj_gnom, gnom_spheroid)
// Factory entry(s)
BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_ENTRY_FI(gnom_entry, gnom_spheroid)
BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_BEGIN(gnom_init)
{
BOOST_GEOMETRY_PROJECTIONS_DETAIL_FACTORY_INIT_ENTRY(gnom, gnom_entry);
}
} // namespace detail
#endif // doxygen
} // namespace projections
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_PROJECTIONS_GNOM_HPP