1 // Boost.Geometry (aka GGL, Generic Geometry Library) 2 3 // Copyright (c) 2008-2012 Bruno Lalande, Paris, France. 4 // Copyright (c) 2008-2012 Barend Gehrels, Amsterdam, the Netherlands. 5 // Copyright (c) 2009-2012 Mateusz Loskot, London, UK. 6 7 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library 8 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands. 9 10 // Use, modification and distribution is subject to the Boost Software License, 11 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at 12 // http://www.boost.org/LICENSE_1_0.txt) 13 14 #ifndef BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_SEGMENT_CONCEPT_HPP 15 #define BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_SEGMENT_CONCEPT_HPP 16 17 #include <boost/concept_check.hpp> 18 #include <boost/core/ignore_unused.hpp> 19 20 #include <boost/geometry/geometries/concepts/point_concept.hpp> 21 22 #include <boost/geometry/core/access.hpp> 23 #include <boost/geometry/core/point_type.hpp> 24 25 26 namespace boost { namespace geometry { namespace concepts 27 { 28 29 30 /*! 31 \brief Segment concept. 32 \ingroup concepts 33 \details Formal definition: 34 The segment concept is defined as following: 35 - there must be a specialization of traits::tag defining segment_tag as type 36 - there must be a specialization of traits::point_type to define the 37 underlying point type (even if it does not consist of points, it should define 38 this type, to indicate the points it can work with) 39 - there must be a specialization of traits::indexed_access, per index 40 and per dimension, with two functions: 41 - get to get a coordinate value 42 - set to set a coordinate value (this one is not checked for ConstSegment) 43 44 \note The segment concept is similar to the box concept, defining another tag. 45 However, the box concept assumes the index as min_corner, max_corner, while 46 for the segment concept there is no assumption. 47 */ 48 template <typename Geometry> 49 class Segment 50 { 51 #ifndef DOXYGEN_NO_CONCEPT_MEMBERS 52 typedef typename point_type<Geometry>::type point_type; 53 54 BOOST_CONCEPT_ASSERT( (concepts::Point<point_type>) ); 55 56 57 template <size_t Index, size_t Dimension, size_t DimensionCount> 58 struct dimension_checker 59 { applyboost::geometry::concepts::Segment::dimension_checker60 static void apply() 61 { 62 Geometry* s = 0; 63 geometry::set<Index, Dimension>(*s, geometry::get<Index, Dimension>(*s)); 64 dimension_checker<Index, Dimension + 1, DimensionCount>::apply(); 65 } 66 }; 67 68 template <size_t Index, size_t DimensionCount> 69 struct dimension_checker<Index, DimensionCount, DimensionCount> 70 { applyboost::geometry::concepts::Segment::dimension_checker71 static void apply() {} 72 }; 73 74 public : 75 BOOST_CONCEPT_USAGE(Segment)76 BOOST_CONCEPT_USAGE(Segment) 77 { 78 static const size_t n = dimension<point_type>::type::value; 79 dimension_checker<0, 0, n>::apply(); 80 dimension_checker<1, 0, n>::apply(); 81 } 82 #endif 83 }; 84 85 86 /*! 87 \brief Segment concept (const version). 88 \ingroup const_concepts 89 \details The ConstSegment concept verifies the same as the Segment concept, 90 but does not verify write access. 91 */ 92 template <typename Geometry> 93 class ConstSegment 94 { 95 #ifndef DOXYGEN_NO_CONCEPT_MEMBERS 96 typedef typename point_type<Geometry>::type point_type; 97 typedef typename coordinate_type<Geometry>::type coordinate_type; 98 99 BOOST_CONCEPT_ASSERT( (concepts::ConstPoint<point_type>) ); 100 101 102 template <size_t Index, size_t Dimension, size_t DimensionCount> 103 struct dimension_checker 104 { applyboost::geometry::concepts::ConstSegment::dimension_checker105 static void apply() 106 { 107 const Geometry* s = 0; 108 coordinate_type coord(geometry::get<Index, Dimension>(*s)); 109 boost::ignore_unused(coord); 110 dimension_checker<Index, Dimension + 1, DimensionCount>::apply(); 111 } 112 }; 113 114 template <size_t Index, size_t DimensionCount> 115 struct dimension_checker<Index, DimensionCount, DimensionCount> 116 { applyboost::geometry::concepts::ConstSegment::dimension_checker117 static void apply() {} 118 }; 119 120 public : 121 BOOST_CONCEPT_USAGE(ConstSegment)122 BOOST_CONCEPT_USAGE(ConstSegment) 123 { 124 static const size_t n = dimension<point_type>::type::value; 125 dimension_checker<0, 0, n>::apply(); 126 dimension_checker<1, 0, n>::apply(); 127 } 128 #endif 129 }; 130 131 132 }}} // namespace boost::geometry::concepts 133 134 135 #endif // BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_SEGMENT_CONCEPT_HPP 136