libcarla/include/system/boost/geometry/algorithms/num_segments.hpp
2024-10-18 13:19:59 +08:00

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// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2014-2021, Oracle and/or its affiliates.
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// Licensed under the Boost Software License version 1.0.
// http://www.boost.org/users/license.html
#ifndef BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP
#define BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP
#include <cstddef>
#include <boost/range/size.hpp>
#include <boost/range/value_type.hpp>
#include <boost/geometry/algorithms/detail/counting.hpp>
#include <boost/geometry/algorithms/detail/visit.hpp>
#include <boost/geometry/algorithms/not_implemented.hpp>
#include <boost/geometry/core/closure.hpp>
#include <boost/geometry/core/tag.hpp>
#include <boost/geometry/core/tags.hpp>
#include <boost/geometry/core/visit.hpp>
#include <boost/geometry/geometries/adapted/boost_variant.hpp> // For backward compatibility
#include <boost/geometry/geometries/concepts/check.hpp>
#include <boost/geometry/util/range.hpp>
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace num_segments
{
struct range_count
{
template <typename Range>
static inline std::size_t apply(Range const& range)
{
std::size_t n = boost::size(range);
if ( n <= 1 )
{
return 0;
}
return
geometry::closure<Range>::value == open
?
n
:
static_cast<std::size_t>(n - 1);
}
};
}} // namespace detail::num_segments
#endif // DOXYGEN_NO_DETAIL
#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{
template <typename Geometry, typename Tag = typename tag<Geometry>::type>
struct num_segments
: not_implemented<Tag>
{};
template <typename Geometry>
struct num_segments<Geometry, point_tag>
: detail::counting::other_count<0>
{};
// the number of segments (1-dimensional faces) of the hypercube is
// given by the formula: d * 2^(d-1), where d is the dimension of the
// hypercube; see also:
// http://en.wikipedia.org/wiki/Hypercube
template <typename Geometry>
struct num_segments<Geometry, box_tag>
: detail::counting::other_count
<
geometry::dimension<Geometry>::value
* (1 << (geometry::dimension<Geometry>::value - 1))
>
{};
template <typename Geometry>
struct num_segments<Geometry, segment_tag>
: detail::counting::other_count<1>
{};
template <typename Geometry>
struct num_segments<Geometry, linestring_tag>
: detail::num_segments::range_count
{};
template <typename Geometry>
struct num_segments<Geometry, ring_tag>
: detail::num_segments::range_count
{};
template <typename Geometry>
struct num_segments<Geometry, polygon_tag>
: detail::counting::polygon_count<detail::num_segments::range_count>
{};
template <typename Geometry>
struct num_segments<Geometry, multi_point_tag>
: detail::counting::other_count<0>
{};
template <typename Geometry>
struct num_segments<Geometry, multi_linestring_tag>
: detail::counting::multi_count
<
num_segments< typename boost::range_value<Geometry>::type>
>
{};
template <typename Geometry>
struct num_segments<Geometry, multi_polygon_tag>
: detail::counting::multi_count
<
num_segments< typename boost::range_value<Geometry>::type>
>
{};
} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH
namespace resolve_dynamic
{
template <typename Geometry, typename Tag = typename tag<Geometry>::type>
struct num_segments
{
static inline std::size_t apply(Geometry const& geometry)
{
concepts::check<Geometry const>();
return dispatch::num_segments<Geometry>::apply(geometry);
}
};
template <typename Geometry>
struct num_segments<Geometry, dynamic_geometry_tag>
{
static inline std::size_t apply(Geometry const& geometry)
{
std::size_t result = 0;
traits::visit<Geometry>::apply([&](auto const& g)
{
result = num_segments<util::remove_cref_t<decltype(g)>>::apply(g);
}, geometry);
return result;
}
};
template <typename Geometry>
struct num_segments<Geometry, geometry_collection_tag>
{
static inline std::size_t apply(Geometry const& geometry)
{
std::size_t result = 0;
detail::visit_breadth_first([&](auto const& g)
{
result += num_segments<util::remove_cref_t<decltype(g)>>::apply(g);
return true;
}, geometry);
return result;
}
};
} // namespace resolve_dynamic
/*!
\brief \brief_calc{number of segments}
\ingroup num_segments
\details \details_calc{num_segments, number of segments}.
\tparam Geometry \tparam_geometry
\param geometry \param_geometry
\return \return_calc{number of segments}
\qbk{[include reference/algorithms/num_segments.qbk]}
*/
template <typename Geometry>
inline std::size_t num_segments(Geometry const& geometry)
{
return resolve_dynamic::num_segments<Geometry>::apply(geometry);
}
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ALGORITHMS_NUM_SEGMENTS_HPP