Chris@16: // Boost.Geometry (aka GGL, Generic Geometry Library)
Chris@16: 
Chris@16: // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
Chris@16: // Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
Chris@16: // Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
Chris@16: 
Chris@16: // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
Chris@16: // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
Chris@16: 
Chris@16: // Use, modification and distribution is subject to the Boost Software License,
Chris@16: // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
Chris@16: #define BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
Chris@16: 
Chris@16: #include <cstddef>
Chris@16: 
Chris@16: #include <boost/numeric/conversion/cast.hpp>
Chris@16: 
Chris@101: #include <boost/variant/apply_visitor.hpp>
Chris@101: #include <boost/variant/static_visitor.hpp>
Chris@101: #include <boost/variant/variant_fwd.hpp>
Chris@16: 
Chris@16: #include <boost/geometry/algorithms/clear.hpp>
Chris@101: #include <boost/geometry/algorithms/envelope.hpp>
Chris@16: #include <boost/geometry/algorithms/not_implemented.hpp>
Chris@16: #include <boost/geometry/arithmetic/arithmetic.hpp>
Chris@16: #include <boost/geometry/geometries/concepts/check.hpp>
Chris@101: #include <boost/geometry/geometries/box.hpp>
Chris@16: #include <boost/geometry/util/math.hpp>
Chris@16: 
Chris@101: #include <boost/geometry/algorithms/detail/buffer/buffer_inserter.hpp>
Chris@16: 
Chris@16: namespace boost { namespace geometry
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DETAIL
Chris@16: namespace detail { namespace buffer
Chris@16: {
Chris@16: 
Chris@16: template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t D, std::size_t N>
Chris@16: struct box_loop
Chris@16: {
Chris@16:     typedef typename coordinate_type<BoxOut>::type coordinate_type;
Chris@16: 
Chris@16:     static inline void apply(BoxIn const& box_in, T const& distance, BoxOut& box_out)
Chris@16:     {
Chris@16:         coordinate_type d = distance;
Chris@16:         set<C, D>(box_out, get<C, D>(box_in) + d);
Chris@16:         box_loop<BoxIn, BoxOut, T, C, D + 1, N>::apply(box_in, distance, box_out);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t N>
Chris@16: struct box_loop<BoxIn, BoxOut, T, C, N, N>
Chris@16: {
Chris@16:     static inline void apply(BoxIn const&, T const&, BoxOut&) {}
Chris@16: };
Chris@16: 
Chris@16: // Extends a box with the same amount in all directions
Chris@16: template<typename BoxIn, typename BoxOut, typename T>
Chris@16: inline void buffer_box(BoxIn const& box_in, T const& distance, BoxOut& box_out)
Chris@16: {
Chris@16:     assert_dimension_equal<BoxIn, BoxOut>();
Chris@16: 
Chris@16:     static const std::size_t N = dimension<BoxIn>::value;
Chris@16: 
Chris@16:     box_loop<BoxIn, BoxOut, T, min_corner, 0, N>::apply(box_in, -distance, box_out);
Chris@16:     box_loop<BoxIn, BoxOut, T, max_corner, 0, N>::apply(box_in, distance, box_out);
Chris@16: }
Chris@16: 
Chris@16: 
Chris@16: 
Chris@16: }} // namespace detail::buffer
Chris@16: #endif // DOXYGEN_NO_DETAIL
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DISPATCH
Chris@16: namespace dispatch
Chris@16: {
Chris@16: 
Chris@16: template
Chris@16: <
Chris@16:     typename Input,
Chris@16:     typename Output,
Chris@16:     typename TagIn = typename tag<Input>::type,
Chris@16:     typename TagOut = typename tag<Output>::type
Chris@16: >
Chris@16: struct buffer: not_implemented<TagIn, TagOut>
Chris@16: {};
Chris@16: 
Chris@16: 
Chris@16: template <typename BoxIn, typename BoxOut>
Chris@16: struct buffer<BoxIn, BoxOut, box_tag, box_tag>
Chris@16: {
Chris@16:     template <typename Distance>
Chris@16:     static inline void apply(BoxIn const& box_in, Distance const& distance,
Chris@101:                 Distance const& , BoxOut& box_out)
Chris@16:     {
Chris@16:         detail::buffer::buffer_box(box_in, distance, box_out);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: } // namespace dispatch
Chris@16: #endif // DOXYGEN_NO_DISPATCH
Chris@16: 
Chris@16: 
Chris@101: namespace resolve_variant {
Chris@101: 
Chris@101: template <typename Geometry>
Chris@101: struct buffer
Chris@101: {
Chris@101:     template <typename Distance, typename GeometryOut>
Chris@101:     static inline void apply(Geometry const& geometry,
Chris@101:                              Distance const& distance,
Chris@101:                              Distance const& chord_length,
Chris@101:                              GeometryOut& out)
Chris@101:     {
Chris@101:         dispatch::buffer<Geometry, GeometryOut>::apply(geometry, distance, chord_length, out);
Chris@101:     }
Chris@101: };
Chris@101: 
Chris@101: template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
Chris@101: struct buffer<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
Chris@101: {
Chris@101:     template <typename Distance, typename GeometryOut>
Chris@101:     struct visitor: boost::static_visitor<void>
Chris@101:     {
Chris@101:         Distance const& m_distance;
Chris@101:         Distance const& m_chord_length;
Chris@101:         GeometryOut& m_out;
Chris@101: 
Chris@101:         visitor(Distance const& distance,
Chris@101:                 Distance const& chord_length,
Chris@101:                 GeometryOut& out)
Chris@101:         : m_distance(distance),
Chris@101:           m_chord_length(chord_length),
Chris@101:           m_out(out)
Chris@101:         {}
Chris@101: 
Chris@101:         template <typename Geometry>
Chris@101:         void operator()(Geometry const& geometry) const
Chris@101:         {
Chris@101:             buffer<Geometry>::apply(geometry, m_distance, m_chord_length, m_out);
Chris@101:         }
Chris@101:     };
Chris@101: 
Chris@101:     template <typename Distance, typename GeometryOut>
Chris@101:     static inline void apply(
Chris@101:         boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> const& geometry,
Chris@101:         Distance const& distance,
Chris@101:         Distance const& chord_length,
Chris@101:         GeometryOut& out
Chris@101:     )
Chris@101:     {
Chris@101:         boost::apply_visitor(visitor<Distance, GeometryOut>(distance, chord_length, out), geometry);
Chris@101:     }
Chris@101: };
Chris@101: 
Chris@101: } // namespace resolve_variant
Chris@101: 
Chris@101: 
Chris@16: /*!
Chris@16: \brief \brief_calc{buffer}
Chris@16: \ingroup buffer
Chris@16: \details \details_calc{buffer, \det_buffer}.
Chris@16: \tparam Input \tparam_geometry
Chris@16: \tparam Output \tparam_geometry
Chris@16: \tparam Distance \tparam_numeric
Chris@16: \param geometry_in \param_geometry
Chris@16: \param geometry_out \param_geometry
Chris@16: \param distance The distance to be used for the buffer
Chris@16: \param chord_length (optional) The length of the chord's in the generated arcs around points or bends
Chris@16: 
Chris@16: \qbk{[include reference/algorithms/buffer.qbk]}
Chris@16:  */
Chris@16: template <typename Input, typename Output, typename Distance>
Chris@16: inline void buffer(Input const& geometry_in, Output& geometry_out,
Chris@16:             Distance const& distance, Distance const& chord_length = -1)
Chris@16: {
Chris@16:     concept::check<Input const>();
Chris@16:     concept::check<Output>();
Chris@16: 
Chris@101:     resolve_variant::buffer<Input>::apply(geometry_in, distance, chord_length, geometry_out);
Chris@16: }
Chris@16: 
Chris@16: /*!
Chris@16: \brief \brief_calc{buffer}
Chris@16: \ingroup buffer
Chris@16: \details \details_calc{return_buffer, \det_buffer}. \details_return{buffer}.
Chris@16: \tparam Input \tparam_geometry
Chris@16: \tparam Output \tparam_geometry
Chris@16: \tparam Distance \tparam_numeric
Chris@16: \param geometry \param_geometry
Chris@16: \param distance The distance to be used for the buffer
Chris@16: \param chord_length (optional) The length of the chord's in the generated arcs
Chris@101:     around points or bends (RESERVED, NOT YET USED)
Chris@16: \return \return_calc{buffer}
Chris@16:  */
Chris@16: template <typename Output, typename Input, typename Distance>
Chris@16: Output return_buffer(Input const& geometry, Distance const& distance, Distance const& chord_length = -1)
Chris@16: {
Chris@16:     concept::check<Input const>();
Chris@16:     concept::check<Output>();
Chris@16: 
Chris@16:     Output geometry_out;
Chris@16: 
Chris@101:     resolve_variant::buffer<Input>::apply(geometry, distance, chord_length, geometry_out);
Chris@16: 
Chris@16:     return geometry_out;
Chris@16: }
Chris@16: 
Chris@101: /*!
Chris@101: \brief \brief_calc{buffer}
Chris@101: \ingroup buffer
Chris@101: \details \details_calc{buffer, \det_buffer}.
Chris@101: \tparam GeometryIn \tparam_geometry
Chris@101: \tparam MultiPolygon \tparam_geometry{MultiPolygon}
Chris@101: \tparam DistanceStrategy A strategy defining distance (or radius)
Chris@101: \tparam SideStrategy A strategy defining creation along sides
Chris@101: \tparam JoinStrategy A strategy defining creation around convex corners
Chris@101: \tparam EndStrategy A strategy defining creation at linestring ends
Chris@101: \tparam PointStrategy A strategy defining creation around points
Chris@101: \param geometry_in \param_geometry
Chris@101: \param geometry_out output multi polygon (or std:: collection of polygons),
Chris@101:     will contain a buffered version of the input geometry
Chris@101: \param distance_strategy The distance strategy to be used
Chris@101: \param side_strategy The side strategy to be used
Chris@101: \param join_strategy The join strategy to be used
Chris@101: \param end_strategy The end strategy to be used
Chris@101: \param point_strategy The point strategy to be used
Chris@101: 
Chris@101: \qbk{distinguish,with strategies}
Chris@101: \qbk{[include reference/algorithms/buffer_with_strategies.qbk]}
Chris@101:  */
Chris@101: template
Chris@101: <
Chris@101:     typename GeometryIn,
Chris@101:     typename MultiPolygon,
Chris@101:     typename DistanceStrategy,
Chris@101:     typename SideStrategy,
Chris@101:     typename JoinStrategy,
Chris@101:     typename EndStrategy,
Chris@101:     typename PointStrategy
Chris@101: >
Chris@101: inline void buffer(GeometryIn const& geometry_in,
Chris@101:                 MultiPolygon& geometry_out,
Chris@101:                 DistanceStrategy const& distance_strategy,
Chris@101:                 SideStrategy const& side_strategy,
Chris@101:                 JoinStrategy const& join_strategy,
Chris@101:                 EndStrategy const& end_strategy,
Chris@101:                 PointStrategy const& point_strategy)
Chris@101: {
Chris@101:     typedef typename boost::range_value<MultiPolygon>::type polygon_type;
Chris@101:     concept::check<GeometryIn const>();
Chris@101:     concept::check<polygon_type>();
Chris@101: 
Chris@101:     typedef typename point_type<GeometryIn>::type point_type;
Chris@101:     typedef typename rescale_policy_type<point_type>::type rescale_policy_type;
Chris@101: 
Chris@101:     geometry_out.clear();
Chris@101: 
Chris@101:     model::box<point_type> box;
Chris@101:     envelope(geometry_in, box);
Chris@101:     buffer(box, box, distance_strategy.max_distance(join_strategy, end_strategy));
Chris@101: 
Chris@101:     rescale_policy_type rescale_policy
Chris@101:             = boost::geometry::get_rescale_policy<rescale_policy_type>(box);
Chris@101: 
Chris@101:     detail::buffer::buffer_inserter<polygon_type>(geometry_in, std::back_inserter(geometry_out),
Chris@101:                 distance_strategy,
Chris@101:                 side_strategy,
Chris@101:                 join_strategy,
Chris@101:                 end_strategy,
Chris@101:                 point_strategy,
Chris@101:                 rescale_policy);
Chris@101: }
Chris@101: 
Chris@101: 
Chris@16: }} // namespace boost::geometry
Chris@16: 
Chris@16: #endif // BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP