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// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2015 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2015 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2015 Mateusz Loskot, London, UK.
// Copyright (c) 2014-2015 Samuel Debionne, Grenoble, France.
// This file was modified by Oracle on 2015, 2016, 2017.
// Modifications copyright (c) 2015-2017, Oracle and/or its affiliates.
// Contributed and/or modified by Vissarion Fysikopoulos, on behalf of Oracle
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
// Distributed under 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)
#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_POINT_HPP
#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_POINT_HPP
#include <cstddef>
#include <algorithm>
#include <functional>
#include <boost/mpl/assert.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/geometry/core/access.hpp>
#include <boost/geometry/core/coordinate_dimension.hpp>
#include <boost/geometry/core/coordinate_system.hpp>
#include <boost/geometry/core/coordinate_type.hpp>
#include <boost/geometry/core/tags.hpp>
#include <boost/geometry/util/math.hpp>
#include <boost/geometry/util/select_coordinate_type.hpp>
#include <boost/geometry/algorithms/detail/normalize.hpp>
#include <boost/geometry/algorithms/detail/envelope/transform_units.hpp>
#include <boost/geometry/algorithms/dispatch/expand.hpp>
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace expand
{
template <std::size_t Dimension, std::size_t DimensionCount>
struct point_loop
{
template <typename Box, typename Point, typename Strategy>
static inline void apply(Box& box, Point const& source, Strategy const& strategy)
{
typedef typename select_coordinate_type
<
Point, Box
>::type coordinate_type;
std::less<coordinate_type> less;
std::greater<coordinate_type> greater;
coordinate_type const coord = get<Dimension>(source);
if (less(coord, get<min_corner, Dimension>(box)))
{
set<min_corner, Dimension>(box, coord);
}
if (greater(coord, get<max_corner, Dimension>(box)))
{
set<max_corner, Dimension>(box, coord);
}
point_loop<Dimension + 1, DimensionCount>::apply(box, source, strategy);
}
};
template <std::size_t DimensionCount>
struct point_loop<DimensionCount, DimensionCount>
{
template <typename Box, typename Point, typename Strategy>
static inline void apply(Box&, Point const&, Strategy const&) {}
};
// implementation for the spherical and geographic coordinate systems
template <std::size_t DimensionCount, bool IsEquatorial = true>
struct point_loop_on_spheroid
{
template <typename Box, typename Point, typename Strategy>
static inline void apply(Box& box,
Point const& point,
Strategy const& strategy)
{
typedef typename point_type<Box>::type box_point_type;
typedef typename coordinate_type<Box>::type box_coordinate_type;
typedef typename coordinate_system<Box>::type::units units_type;
typedef math::detail::constants_on_spheroid
<
box_coordinate_type,
units_type
> constants;
// normalize input point and input box
Point p_normalized = detail::return_normalized<Point>(point);
detail::normalize(box, box);
// transform input point to be of the same type as the box point
box_point_type box_point;
detail::envelope::transform_units(p_normalized, box_point);
box_coordinate_type p_lon = geometry::get<0>(box_point);
box_coordinate_type p_lat = geometry::get<1>(box_point);
typename coordinate_type<Box>::type
b_lon_min = geometry::get<min_corner, 0>(box),
b_lat_min = geometry::get<min_corner, 1>(box),
b_lon_max = geometry::get<max_corner, 0>(box),
b_lat_max = geometry::get<max_corner, 1>(box);
if (math::is_latitude_pole<units_type, IsEquatorial>(p_lat))
{
// the point of expansion is the either the north or the
// south pole; the only important coordinate here is the
// pole's latitude, as the longitude can be anything;
// we, thus, take into account the point's latitude only and return
geometry::set<min_corner, 1>(box, (std::min)(p_lat, b_lat_min));
geometry::set<max_corner, 1>(box, (std::max)(p_lat, b_lat_max));
return;
}
if (math::equals(b_lat_min, b_lat_max)
&& math::is_latitude_pole<units_type, IsEquatorial>(b_lat_min))
{
// the box degenerates to either the north or the south pole;
// the only important coordinate here is the pole's latitude,
// as the longitude can be anything;
// we thus take into account the box's latitude only and return
geometry::set<min_corner, 0>(box, p_lon);
geometry::set<min_corner, 1>(box, (std::min)(p_lat, b_lat_min));
geometry::set<max_corner, 0>(box, p_lon);
geometry::set<max_corner, 1>(box, (std::max)(p_lat, b_lat_max));
return;
}
// update latitudes
b_lat_min = (std::min)(b_lat_min, p_lat);
b_lat_max = (std::max)(b_lat_max, p_lat);
// update longitudes
if (math::smaller(p_lon, b_lon_min))
{
box_coordinate_type p_lon_shifted = p_lon + constants::period();
if (math::larger(p_lon_shifted, b_lon_max))
{
// here we could check using: ! math::larger(.., ..)
if (math::smaller(b_lon_min - p_lon, p_lon_shifted - b_lon_max))
{
b_lon_min = p_lon;
}
else
{
b_lon_max = p_lon_shifted;
}
}
}
else if (math::larger(p_lon, b_lon_max))
{
// in this case, and since p_lon is normalized in the range
// (-180, 180], we must have that b_lon_max <= 180
if (b_lon_min < 0
&& math::larger(p_lon - b_lon_max,
constants::period() - p_lon + b_lon_min))
{
b_lon_min = p_lon;
b_lon_max += constants::period();
}
else
{
b_lon_max = p_lon;
}
}
geometry::set<min_corner, 0>(box, b_lon_min);
geometry::set<min_corner, 1>(box, b_lat_min);
geometry::set<max_corner, 0>(box, b_lon_max);
geometry::set<max_corner, 1>(box, b_lat_max);
point_loop
<
2, DimensionCount
>::apply(box, point, strategy);
}
};
}} // namespace detail::expand
#endif // DOXYGEN_NO_DETAIL
#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{
// Box + point -> new box containing also point
template
<
typename BoxOut, typename Point,
typename CSTagOut, typename CSTag
>
struct expand
<
BoxOut, Point,
box_tag, point_tag,
CSTagOut, CSTag
>
{
BOOST_MPL_ASSERT_MSG((false),
NOT_IMPLEMENTED_FOR_THESE_COORDINATE_SYSTEMS,
(types<CSTagOut, CSTag>()));
};
template <typename BoxOut, typename Point>
struct expand
<
BoxOut, Point,
box_tag, point_tag,
cartesian_tag, cartesian_tag
> : detail::expand::point_loop
<
0, dimension<Point>::value
>
{};
template <typename BoxOut, typename Point>
struct expand
<
BoxOut, Point,
box_tag, point_tag,
spherical_equatorial_tag, spherical_equatorial_tag
> : detail::expand::point_loop_on_spheroid
<
dimension<Point>::value
>
{};
template <typename BoxOut, typename Point>
struct expand
<
BoxOut, Point,
box_tag, point_tag,
spherical_polar_tag, spherical_polar_tag
> : detail::expand::point_loop_on_spheroid
<
dimension<Point>::value,
false
>
{};
template
<
typename BoxOut, typename Point
>
struct expand
<
BoxOut, Point,
box_tag, point_tag,
geographic_tag, geographic_tag
> : detail::expand::point_loop_on_spheroid
<
dimension<Point>::value
>
{};
} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_POINT_HPP