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@101: // This file was modified by Oracle on 2014.
Chris@101: // Modifications copyright (c) 2014 Oracle and/or its affiliates.
Chris@101: 
Chris@101: // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
Chris@101: 
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_CORE_CLOSURE_HPP
Chris@16: #define BOOST_GEOMETRY_CORE_CLOSURE_HPP
Chris@16: 
Chris@16: #include <boost/mpl/assert.hpp>
Chris@101: #include <boost/mpl/size_t.hpp>
Chris@101: #include <boost/range/value_type.hpp>
Chris@16: #include <boost/type_traits/remove_const.hpp>
Chris@16: 
Chris@16: #include <boost/geometry/core/ring_type.hpp>
Chris@16: #include <boost/geometry/core/tag.hpp>
Chris@16: #include <boost/geometry/core/tags.hpp>
Chris@16: 
Chris@16: namespace boost { namespace geometry
Chris@16: {
Chris@16: 
Chris@16: 
Chris@16: /*!
Chris@16: \brief Enumerates options for defining if polygons are open or closed
Chris@16: \ingroup enum
Chris@16: \details The enumeration closure_selector describes options for if a polygon is
Chris@101:     open or closed. In a closed polygon the very first point (per ring) should
Chris@16:     be equal to the very last point.
Chris@101:     The specific closing property of a polygon type is defined by the closure
Chris@101:     metafunction. The closure metafunction defines a value, which is one of the
Chris@16:     values enumerated in the closure_selector
Chris@16: 
Chris@16: \qbk{
Chris@16: [heading See also]
Chris@16: [link geometry.reference.core.closure The closure metafunction]
Chris@16: }
Chris@16: */
Chris@16: enum closure_selector
Chris@16: {
Chris@101:     /// Rings are open: first point and last point are different, algorithms
Chris@16:     /// close them explicitly on the fly
Chris@16:     open = 0,
Chris@16:     /// Rings are closed: first point and last point must be the same
Chris@16:     closed = 1,
Chris@101:     /// (Not yet implemented): algorithms first figure out if ring must be
Chris@16:     /// closed on the fly
Chris@16:     closure_undertermined = -1
Chris@16: };
Chris@16: 
Chris@16: namespace traits
Chris@16: {
Chris@16: 
Chris@16: /*!
Chris@16:     \brief Traits class indicating if points within a
Chris@16:         ring or (multi)polygon are closed (last point == first point),
Chris@16:         open or not known.
Chris@16:     \ingroup traits
Chris@16:     \par Geometries:
Chris@16:         - ring
Chris@16:     \tparam G geometry
Chris@16: */
Chris@16: template <typename G>
Chris@16: struct closure
Chris@16: {
Chris@16:     static const closure_selector value = closed;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: } // namespace traits
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DETAIL
Chris@16: namespace core_detail { namespace closure
Chris@16: {
Chris@16: 
Chris@16: struct closed
Chris@16: {
Chris@16:     static const closure_selector value = geometry::closed;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: /// Metafunction to define the minimum size of a ring:
Chris@16: /// 3 for open rings, 4 for closed rings
Chris@16: template <closure_selector Closure>
Chris@16: struct minimum_ring_size {};
Chris@16: 
Chris@16: template <>
Chris@101: struct minimum_ring_size<geometry::closed> : boost::mpl::size_t<4> {};
Chris@16: 
Chris@16: template <>
Chris@101: struct minimum_ring_size<geometry::open> : boost::mpl::size_t<3> {};
Chris@16: 
Chris@16: 
Chris@16: }} // namespace detail::point_order
Chris@16: #endif // DOXYGEN_NO_DETAIL
Chris@16: 
Chris@16: 
Chris@16: 
Chris@16: #ifndef DOXYGEN_NO_DISPATCH
Chris@16: namespace core_dispatch
Chris@16: {
Chris@16: 
Chris@16: template <typename Tag, typename Geometry>
Chris@16: struct closure
Chris@16: {
Chris@16:     BOOST_MPL_ASSERT_MSG
Chris@16:         (
Chris@16:             false, NOT_IMPLEMENTED_FOR_THIS_GEOMETRY_TYPE
Chris@16:             , (types<Geometry>)
Chris@16:         );
Chris@16: };
Chris@16: 
Chris@16: template <typename Box>
Chris@16: struct closure<point_tag, Box> : public core_detail::closure::closed {};
Chris@16: 
Chris@16: template <typename Box>
Chris@16: struct closure<box_tag, Box> : public core_detail::closure::closed {};
Chris@16: 
Chris@16: template <typename Box>
Chris@16: struct closure<segment_tag, Box> : public core_detail::closure::closed {};
Chris@16: 
Chris@16: template <typename LineString>
Chris@101: struct closure<linestring_tag, LineString>
Chris@16:     : public core_detail::closure::closed {};
Chris@16: 
Chris@16: 
Chris@16: template <typename Ring>
Chris@16: struct closure<ring_tag, Ring>
Chris@16: {
Chris@101:     static const closure_selector value
Chris@16:         = geometry::traits::closure<Ring>::value;
Chris@16: };
Chris@16: 
Chris@101: // Specialization for Polygon: the closure is the closure of its rings
Chris@16: template <typename Polygon>
Chris@16: struct closure<polygon_tag, Polygon>
Chris@16: {
Chris@16:     static const closure_selector value = core_dispatch::closure
Chris@16:         <
Chris@16:             ring_tag,
Chris@16:             typename ring_type<polygon_tag, Polygon>::type
Chris@16:         >::value ;
Chris@16: };
Chris@16: 
Chris@101: template <typename MultiPoint>
Chris@101: struct closure<multi_point_tag, MultiPoint>
Chris@101:     : public core_detail::closure::closed {};
Chris@101: 
Chris@101: template <typename MultiLinestring>
Chris@101: struct closure<multi_linestring_tag, MultiLinestring>
Chris@101:     : public core_detail::closure::closed {};
Chris@101: 
Chris@101: // Specialization for MultiPolygon: the closure is the closure of Polygon's rings
Chris@101: template <typename MultiPolygon>
Chris@101: struct closure<multi_polygon_tag, MultiPolygon>
Chris@101: {
Chris@101:     static const closure_selector value = core_dispatch::closure
Chris@101:         <
Chris@101:             polygon_tag,
Chris@101:             typename boost::range_value<MultiPolygon>::type
Chris@101:         >::value ;
Chris@101: };
Chris@16: 
Chris@16: } // namespace core_dispatch
Chris@16: #endif // DOXYGEN_NO_DISPATCH
Chris@16: 
Chris@16: 
Chris@16: /*!
Chris@101: \brief \brief_meta{value, closure (clockwise\, counterclockwise),
Chris@16:     \meta_geometry_type}
Chris@16: \tparam Geometry \tparam_geometry
Chris@16: \ingroup core
Chris@16: 
Chris@16: \qbk{[include reference/core/closure.qbk]}
Chris@16: */
Chris@16: template <typename Geometry>
Chris@16: struct closure
Chris@16: {
Chris@16:     static const closure_selector value = core_dispatch::closure
Chris@16:         <
Chris@16:             typename tag<Geometry>::type,
Chris@101:             typename util::bare_type<Geometry>::type
Chris@16:         >::value;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: }} // namespace boost::geometry
Chris@16: 
Chris@16: 
Chris@16: #endif // BOOST_GEOMETRY_CORE_CLOSURE_HPP