| // Boost.Geometry (aka GGL, Generic Geometry Library) |
| |
| // Copyright (c) 2007-2011 Barend Gehrels, Amsterdam, the Netherlands. |
| // Copyright (c) 2008-2011 Bruno Lalande, Paris, France. |
| // Copyright (c) 2009-2011 Mateusz Loskot, London, UK. |
| |
| // 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_CORE_RING_TYPE_HPP |
| #define BOOST_GEOMETRY_CORE_RING_TYPE_HPP |
| |
| |
| #include <boost/mpl/assert.hpp> |
| #include <boost/mpl/if.hpp> |
| #include <boost/type_traits/remove_const.hpp> |
| |
| |
| #include <boost/geometry/core/tag.hpp> |
| #include <boost/geometry/core/tags.hpp> |
| |
| |
| namespace boost { namespace geometry |
| { |
| |
| namespace traits |
| { |
| |
| |
| /*! |
| \brief Traits class to indicate ring-type of a polygon's exterior ring/interior rings |
| \ingroup traits |
| \par Geometries: |
| - polygon |
| \par Specializations should provide: |
| - typedef XXX type ( e.g. ring<P> ) |
| \tparam Geometry geometry |
| */ |
| template <typename Geometry> |
| struct ring_const_type |
| { |
| BOOST_MPL_ASSERT_MSG |
| ( |
| false, NOT_IMPLEMENTED_FOR_THIS_GEOMETRY_TYPE |
| , (types<Geometry>) |
| ); |
| }; |
| |
| template <typename Geometry> |
| struct ring_mutable_type |
| { |
| BOOST_MPL_ASSERT_MSG |
| ( |
| false, NOT_IMPLEMENTED_FOR_THIS_GEOMETRY_TYPE |
| , (types<Geometry>) |
| ); |
| }; |
| |
| |
| } // namespace traits |
| |
| |
| #ifndef DOXYGEN_NO_DISPATCH |
| namespace core_dispatch |
| { |
| |
| template <typename GeometryTag, typename Geometry> |
| struct ring_return_type |
| {}; |
| |
| |
| template <typename LineString> |
| struct ring_return_type<linestring_tag, LineString> |
| { |
| typedef LineString& type; |
| }; |
| |
| |
| template <typename Ring> |
| struct ring_return_type<ring_tag, Ring> |
| { |
| typedef Ring& type; |
| }; |
| |
| |
| template <typename Polygon> |
| struct ring_return_type<polygon_tag, Polygon> |
| { |
| typedef typename boost::remove_const<Polygon>::type nc_polygon_type; |
| |
| typedef typename mpl::if_ |
| < |
| boost::is_const<Polygon>, |
| typename traits::ring_const_type<nc_polygon_type>::type, |
| typename traits::ring_mutable_type<nc_polygon_type>::type |
| >::type type; |
| }; |
| |
| |
| template <typename GeometryTag, typename Geometry> |
| struct ring_type |
| {}; |
| |
| |
| template <typename Ring> |
| struct ring_type<ring_tag, Ring> |
| { |
| typedef Ring type; |
| }; |
| |
| |
| template <typename Polygon> |
| struct ring_type<polygon_tag, Polygon> |
| { |
| typedef typename boost::remove_reference |
| < |
| typename ring_return_type<polygon_tag, Polygon>::type |
| >::type type; |
| }; |
| |
| |
| |
| |
| |
| } // namespace core_dispatch |
| #endif |
| |
| |
| /*! |
| \brief \brief_meta{type, ring_type, \meta_geometry_type} |
| \details A polygon contains one exterior ring |
| and zero or more interior rings (holes). |
| This metafunction retrieves the type of the rings. |
| Exterior ring and each of the interior rings all have the same ring_type. |
| \tparam Geometry A type fullfilling the Ring, Polygon or MultiPolygon concept. |
| \ingroup core |
| |
| \qbk{[include reference/core/ring_type.qbk]} |
| */ |
| template <typename Geometry> |
| struct ring_type |
| { |
| typedef typename core_dispatch::ring_type |
| < |
| typename tag<Geometry>::type, |
| Geometry |
| >::type type; |
| }; |
| |
| |
| template <typename Geometry> |
| struct ring_return_type |
| { |
| typedef typename core_dispatch::ring_return_type |
| < |
| typename tag<Geometry>::type, |
| Geometry |
| >::type type; |
| }; |
| |
| |
| }} // namespace boost::geometry |
| |
| |
| #endif // BOOST_GEOMETRY_CORE_RING_TYPE_HPP |