1 // Boost.Geometry (aka GGL, Generic Geometry Library)
2
3 // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
4
5 // This file was modified by Oracle on 2013, 2014.
6 // Modifications copyright (c) 2013-2014, Oracle and/or its affiliates.
7
8 // Use, modification and distribution is subject to the Boost Software License,
9 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
10 // http://www.boost.org/LICENSE_1_0.txt)
11
12 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
13
14 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_SUB_RANGE_HPP
15 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_SUB_RANGE_HPP
16
17 #include <boost/mpl/if.hpp>
18
19 #include <boost/geometry/core/assert.hpp>
20 #include <boost/geometry/util/range.hpp>
21
22 namespace boost { namespace geometry {
23
24 #ifndef DOXYGEN_NO_DETAIL
25
26 #ifndef DOXYGEN_NO_DISPATCH
27 namespace detail_dispatch {
28
29 template <typename Geometry,
30 typename Tag = typename geometry::tag<Geometry>::type,
31 bool IsMulti = boost::is_base_of<multi_tag, Tag>::value>
32 struct sub_range : not_implemented<Tag>
33 {};
34
35 template <typename Geometry, typename Tag>
36 struct sub_range<Geometry, Tag, false>
37 {
38 typedef Geometry & return_type;
39
40 template <typename Id> static inline
applyboost::geometry::detail_dispatch::sub_range41 return_type apply(Geometry & geometry, Id const&)
42 {
43 return geometry;
44 }
45 };
46
47 template <typename Geometry>
48 struct sub_range<Geometry, polygon_tag, false>
49 {
50 typedef typename geometry::ring_return_type<Geometry>::type return_type;
51
52 template <typename Id> static inline
applyboost::geometry::detail_dispatch::sub_range53 return_type apply(Geometry & geometry, Id const& id)
54 {
55 if ( id.ring_index < 0 )
56 {
57 return geometry::exterior_ring(geometry);
58 }
59 else
60 {
61 typedef typename boost::range_size
62 <
63 typename geometry::interior_type<Geometry>::type
64 >::type size_type;
65 size_type const ri = static_cast<size_type>(id.ring_index);
66 return range::at(geometry::interior_rings(geometry), ri);
67 }
68 }
69 };
70
71 template <typename Geometry, typename Tag>
72 struct sub_range<Geometry, Tag, true>
73 {
74 typedef typename boost::range_value<Geometry>::type value_type;
75 typedef typename boost::mpl::if_c
76 <
77 boost::is_const<Geometry>::value,
78 typename boost::add_const<value_type>::type,
79 value_type
80 >::type sub_type;
81
82 typedef detail_dispatch::sub_range<sub_type> sub_sub_range;
83
84 // TODO: shouldn't it be return_type?
85 typedef typename sub_sub_range::return_type return_type;
86
87 template <typename Id> static inline
applyboost::geometry::detail_dispatch::sub_range88 return_type apply(Geometry & geometry, Id const& id)
89 {
90 BOOST_GEOMETRY_ASSERT(0 <= id.multi_index);
91 typedef typename boost::range_size<Geometry>::type size_type;
92 size_type const mi = static_cast<size_type>(id.multi_index);
93 return sub_sub_range::apply(range::at(geometry, mi), id);
94 }
95 };
96
97 } // namespace detail_dispatch
98 #endif // DOXYGEN_NO_DISPATCH
99
100 namespace detail {
101
102 template <typename Geometry>
103 struct sub_range_return_type
104 {
105 typedef typename detail_dispatch::sub_range<Geometry>::return_type type;
106 };
107
108 // This function also works for geometry::segment_identifier
109
110 template <typename Geometry, typename Id> inline
111 typename sub_range_return_type<Geometry>::type
sub_range(Geometry & geometry,Id const & id)112 sub_range(Geometry & geometry, Id const& id)
113 {
114 return detail_dispatch::sub_range<Geometry>::apply(geometry, id);
115 }
116
117 template <typename Geometry, typename Id> inline
118 typename sub_range_return_type<Geometry const>::type
sub_range(Geometry const & geometry,Id const & id)119 sub_range(Geometry const& geometry, Id const& id)
120 {
121 return detail_dispatch::sub_range<Geometry const>::apply(geometry, id);
122 }
123
124 } // namespace detail
125 #endif // DOXYGEN_NO_DETAIL
126
127 }} // namespace boost::geometry
128
129 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_SUB_RANGE_HPP
130