1 // Boost.Geometry
2
3 // Copyright (c) 2015, 2021, Oracle and/or its affiliates.
4
5 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
6
7 // Distributed under the Boost Software License, Version 1.0.
8 // (See accompanying file LICENSE_1_0.txt or copy at
9 // http://www.boost.org/LICENSE_1_0.txt)
10
11 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_EXPAND_BY_EPSILON_HPP
12 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_EXPAND_BY_EPSILON_HPP
13
14 #include <cstddef>
15 #include <algorithm>
16
17 #include <boost/type_traits/is_floating_point.hpp>
18
19 #include <boost/geometry/core/access.hpp>
20 #include <boost/geometry/core/coordinate_dimension.hpp>
21 #include <boost/geometry/core/coordinate_type.hpp>
22
23 #include <boost/geometry/util/math.hpp>
24
25 #include <boost/geometry/views/detail/indexed_point_view.hpp>
26
27 namespace boost { namespace geometry
28 {
29
30 #ifndef DOXYGEN_NO_DETAIL
31 namespace detail { namespace expand
32 {
33
34 template
35 <
36 typename Point,
37 template <typename> class PlusOrMinus,
38 std::size_t I = 0,
39 std::size_t D = dimension<Point>::value,
40 bool Enable = boost::is_floating_point
41 <
42 typename coordinate_type<Point>::type
43 >::value
44 >
45 struct corner_by_epsilon
46 {
applyboost::geometry::detail::expand::corner_by_epsilon47 static inline void apply(Point & point)
48 {
49 typedef typename coordinate_type<Point>::type coord_type;
50 coord_type const coord = get<I>(point);
51 coord_type const eps = math::scaled_epsilon(coord);
52
53 set<I>(point, PlusOrMinus<coord_type>()(coord, eps));
54
55 corner_by_epsilon<Point, PlusOrMinus, I+1>::apply(point);
56 }
57 };
58
59 template
60 <
61 typename Point,
62 template <typename> class PlusOrMinus,
63 std::size_t I,
64 std::size_t D
65 >
66 struct corner_by_epsilon<Point, PlusOrMinus, I, D, false>
67 {
applyboost::geometry::detail::expand::corner_by_epsilon68 static inline void apply(Point const&) {}
69 };
70
71 template
72 <
73 typename Point,
74 template <typename> class PlusOrMinus,
75 std::size_t D,
76 bool Enable
77 >
78 struct corner_by_epsilon<Point, PlusOrMinus, D, D, Enable>
79 {
applyboost::geometry::detail::expand::corner_by_epsilon80 static inline void apply(Point const&) {}
81 };
82
83 template
84 <
85 typename Point,
86 template <typename> class PlusOrMinus,
87 std::size_t D
88 >
89 struct corner_by_epsilon<Point, PlusOrMinus, D, D, false>
90 {
applyboost::geometry::detail::expand::corner_by_epsilon91 static inline void apply(Point const&) {}
92 };
93
94 } // namespace expand
95
96 template <typename Box>
expand_by_epsilon(Box & box)97 inline void expand_by_epsilon(Box & box)
98 {
99 typedef detail::indexed_point_view<Box, min_corner> min_type;
100 min_type min_point(box);
101 expand::corner_by_epsilon<min_type, std::minus>::apply(min_point);
102
103 typedef detail::indexed_point_view<Box, max_corner> max_type;
104 max_type max_point(box);
105 expand::corner_by_epsilon<max_type, std::plus>::apply(max_point);
106 }
107
108 } // namespace detail
109 #endif // DOXYGEN_NO_DETAIL
110
111 }} // namespace boost::geometry
112
113 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_EXPAND_EXPAND_BY_EPSILON_HPP
114