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
18#include <boost/concept_check.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
26namespace boost { namespace geometry { namespace concept
27{
28
29
30/*!
31\brief Segment concept.
32\ingroup concepts
33\details Formal definition:
34The 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.
45However, the box concept assumes the index as min_corner, max_corner, while
46for the segment concept there is no assumption.
47*/
48template <typename Geometry>
49class Segment
50{
51#ifndef DOXYGEN_NO_CONCEPT_MEMBERS
52 typedef typename point_type<Geometry>::type point_type;
53
54 BOOST_CONCEPT_ASSERT( (concept::Point<point_type>) );
55
56
57 template <size_t Index, size_t Dimension, size_t DimensionCount>
58 struct dimension_checker
59 {
60 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 {
71 static void apply() {}
72 };
73
74public :
75
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,
90but does not verify write access.
91*/
92template <typename Geometry>
93class 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( (concept::ConstPoint<point_type>) );
100
101
102 template <size_t Index, size_t Dimension, size_t DimensionCount>
103 struct dimension_checker
104 {
105 static void apply()
106 {
107 const Geometry* s = 0;
108 coordinate_type coord(geometry::get<Index, Dimension>(*s));
109 boost::ignore_unused_variable_warning(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 {
117 static void apply() {}
118 };
119
120public :
121
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::concept
133
134
135#endif // BOOST_GEOMETRY_GEOMETRIES_CONCEPTS_SEGMENT_CONCEPT_HPP
136

source code of boost/boost/geometry/geometries/concepts/segment_concept.hpp