ecency-mobile/ios/Pods/boost-for-react-native/boost/geometry/algorithms/perimeter.hpp

230 lines
7.2 KiB
C++

// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2014 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2014 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2014 Mateusz Loskot, London, UK.
// This file was modified by Oracle on 2014.
// Modifications copyright (c) 2014, Oracle and/or its affiliates.
// Contributed and/or modified by Menelaos Karavelas, 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.
// 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)
#ifndef BOOST_GEOMETRY_ALGORITHMS_PERIMETER_HPP
#define BOOST_GEOMETRY_ALGORITHMS_PERIMETER_HPP
#include <boost/range/metafunctions.hpp>
#include <boost/variant/apply_visitor.hpp>
#include <boost/variant/static_visitor.hpp>
#include <boost/variant/variant_fwd.hpp>
#include <boost/geometry/algorithms/length.hpp>
#include <boost/geometry/algorithms/detail/calculate_null.hpp>
#include <boost/geometry/algorithms/detail/calculate_sum.hpp>
#include <boost/geometry/algorithms/detail/multi_sum.hpp>
// #include <boost/geometry/algorithms/detail/throw_on_empty_input.hpp>
#include <boost/geometry/core/cs.hpp>
#include <boost/geometry/core/closure.hpp>
#include <boost/geometry/core/tags.hpp>
#include <boost/geometry/geometries/concepts/check.hpp>
#include <boost/geometry/strategies/default_length_result.hpp>
#include <boost/geometry/strategies/default_strategy.hpp>
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{
// Default perimeter is 0.0, specializations implement calculated values
template <typename Geometry, typename Tag = typename tag<Geometry>::type>
struct perimeter : detail::calculate_null
{
typedef typename default_length_result<Geometry>::type return_type;
template <typename Strategy>
static inline return_type apply(Geometry const& geometry, Strategy const& strategy)
{
return calculate_null::apply<return_type>(geometry, strategy);
}
};
template <typename Geometry>
struct perimeter<Geometry, ring_tag>
: detail::length::range_length
<
Geometry,
closure<Geometry>::value
>
{};
template <typename Polygon>
struct perimeter<Polygon, polygon_tag> : detail::calculate_polygon_sum
{
typedef typename default_length_result<Polygon>::type return_type;
typedef detail::length::range_length
<
typename ring_type<Polygon>::type,
closure<Polygon>::value
> policy;
template <typename Strategy>
static inline return_type apply(Polygon const& polygon, Strategy const& strategy)
{
return calculate_polygon_sum::apply<return_type, policy>(polygon, strategy);
}
};
template <typename MultiPolygon>
struct perimeter<MultiPolygon, multi_polygon_tag> : detail::multi_sum
{
typedef typename default_length_result<MultiPolygon>::type return_type;
template <typename Strategy>
static inline return_type apply(MultiPolygon const& multi, Strategy const& strategy)
{
return multi_sum::apply
<
return_type,
perimeter<typename boost::range_value<MultiPolygon>::type>
>(multi, strategy);
}
};
// box,n-sphere: to be implemented
} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH
namespace resolve_strategy {
struct perimeter
{
template <typename Geometry, typename Strategy>
static inline typename default_length_result<Geometry>::type
apply(Geometry const& geometry, Strategy const& strategy)
{
return dispatch::perimeter<Geometry>::apply(geometry, strategy);
}
template <typename Geometry>
static inline typename default_length_result<Geometry>::type
apply(Geometry const& geometry, default_strategy)
{
typedef typename strategy::distance::services::default_strategy
<
point_tag, point_tag, typename point_type<Geometry>::type
>::type strategy_type;
return dispatch::perimeter<Geometry>::apply(geometry, strategy_type());
}
};
} // namespace resolve_strategy
namespace resolve_variant {
template <typename Geometry>
struct perimeter
{
template <typename Strategy>
static inline typename default_length_result<Geometry>::type
apply(Geometry const& geometry, Strategy const& strategy)
{
concepts::check<Geometry const>();
return resolve_strategy::perimeter::apply(geometry, strategy);
}
};
template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
struct perimeter<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
{
typedef typename default_length_result
<
boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>
>::type result_type;
template <typename Strategy>
struct visitor: boost::static_visitor<result_type>
{
Strategy const& m_strategy;
visitor(Strategy const& strategy): m_strategy(strategy) {}
template <typename Geometry>
typename default_length_result<Geometry>::type
operator()(Geometry const& geometry) const
{
return perimeter<Geometry>::apply(geometry, m_strategy);
}
};
template <typename Strategy>
static inline result_type
apply(boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry,
Strategy const& strategy)
{
return boost::apply_visitor(visitor<Strategy>(strategy), geometry);
}
};
} // namespace resolve_variant
/*!
\brief \brief_calc{perimeter}
\ingroup perimeter
\details The function perimeter returns the perimeter of a geometry,
using the default distance-calculation-strategy
\tparam Geometry \tparam_geometry
\param geometry \param_geometry
\return \return_calc{perimeter}
\qbk{[include reference/algorithms/perimeter.qbk]}
*/
template<typename Geometry>
inline typename default_length_result<Geometry>::type perimeter(
Geometry const& geometry)
{
// detail::throw_on_empty_input(geometry);
return resolve_variant::perimeter<Geometry>::apply(geometry, default_strategy());
}
/*!
\brief \brief_calc{perimeter} \brief_strategy
\ingroup perimeter
\details The function perimeter returns the perimeter of a geometry,
using specified strategy
\tparam Geometry \tparam_geometry
\tparam Strategy \tparam_strategy{distance}
\param geometry \param_geometry
\param strategy strategy to be used for distance calculations.
\return \return_calc{perimeter}
\qbk{distinguish,with strategy}
\qbk{[include reference/algorithms/perimeter.qbk]}
*/
template<typename Geometry, typename Strategy>
inline typename default_length_result<Geometry>::type perimeter(
Geometry const& geometry, Strategy const& strategy)
{
// detail::throw_on_empty_input(geometry);
return resolve_variant::perimeter<Geometry>::apply(geometry, strategy);
}
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ALGORITHMS_PERIMETER_HPP