1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
#define BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
#include <cstddef>
#include <boost/numeric/conversion/cast.hpp>
#include <boost/geometry/algorithms/clear.hpp>
#include <boost/geometry/algorithms/detail/disjoint.hpp>
#include <boost/geometry/arithmetic/arithmetic.hpp>
#include <boost/geometry/geometries/concepts/check.hpp>
#include <boost/geometry/geometries/segment.hpp>
#include <boost/geometry/util/math.hpp>
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace buffer
{
template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t D, std::size_t N>
struct box_loop
{
typedef typename coordinate_type<BoxOut>::type coordinate_type;
static inline void apply(BoxIn const& box_in, T const& distance, BoxOut& box_out)
{
coordinate_type d = distance;
set<C, D>(box_out, get<C, D>(box_in) + d);
box_loop<BoxIn, BoxOut, T, C, D + 1, N>::apply(box_in, distance, box_out);
}
};
template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t N>
struct box_loop<BoxIn, BoxOut, T, C, N, N>
{
static inline void apply(BoxIn const&, T const&, BoxOut&) {}
};
// Extends a box with the same amount in all directions
template<typename BoxIn, typename BoxOut, typename T>
inline void buffer_box(BoxIn const& box_in, T const& distance, BoxOut& box_out)
{
assert_dimension_equal<BoxIn, BoxOut>();
static const std::size_t N = dimension<BoxIn>::value;
box_loop<BoxIn, BoxOut, T, min_corner, 0, N>::apply(box_in, -distance, box_out);
box_loop<BoxIn, BoxOut, T, max_corner, 0, N>::apply(box_in, distance, box_out);
}
}} // namespace detail::buffer
#endif // DOXYGEN_NO_DETAIL
#ifndef DOXYGEN_NO_DISPATCH
namespace dispatch
{
template <typename TagIn, typename TagOut, typename Input, typename T, typename Output>
struct buffer {};
template <typename BoxIn, typename T, typename BoxOut>
struct buffer<box_tag, box_tag, BoxIn, T, BoxOut>
{
static inline void apply(BoxIn const& box_in, T const& distance,
T const& , BoxIn& box_out)
{
detail::buffer::buffer_box(box_in, distance, box_out);
}
};
// Many things to do. Point is easy, other geometries require self intersections
// For point, note that it should output as a polygon (like the rest). Buffers
// of a set of geometries are often lateron combined using a "dissolve" operation.
// Two points close to each other get a combined kidney shaped buffer then.
} // namespace dispatch
#endif // DOXYGEN_NO_DISPATCH
/*!
\brief \brief_calc{buffer}
\ingroup buffer
\details \details_calc{buffer, \det_buffer}.
\tparam Input \tparam_geometry
\tparam Output \tparam_geometry
\tparam Distance \tparam_numeric
\param geometry_in \param_geometry
\param geometry_out \param_geometry
\param distance The distance to be used for the buffer
\param chord_length (optional) The length of the chord's in the generated arcs around points or bends
\note Currently only implemented for box, the trivial case, but still useful
\qbk{[include reference/algorithms/buffer.qbk]}
*/
template <typename Input, typename Output, typename Distance>
inline void buffer(Input const& geometry_in, Output& geometry_out,
Distance const& distance, Distance const& chord_length = -1)
{
concept::check<Input const>();
concept::check<Output>();
dispatch::buffer
<
typename tag<Input>::type,
typename tag<Output>::type,
Input,
Distance,
Output
>::apply(geometry_in, distance, chord_length, geometry_out);
}
/*!
\brief \brief_calc{buffer}
\ingroup buffer
\details \details_calc{return_buffer, \det_buffer}. \details_return{buffer}.
\tparam Input \tparam_geometry
\tparam Output \tparam_geometry
\tparam Distance \tparam_numeric
\param geometry \param_geometry
\param distance The distance to be used for the buffer
\param chord_length (optional) The length of the chord's in the generated arcs around points or bends
\return \return_calc{buffer}
*/
template <typename Output, typename Input, typename T>
Output return_buffer(Input const& geometry, T const& distance, T const& chord_length = -1)
{
concept::check<Input const>();
concept::check<Output>();
Output geometry_out;
dispatch::buffer
<
typename tag<Input>::type,
typename tag<Output>::type,
Input,
T,
Output
>::apply(geometry, distance, chord_length, geometry_out);
return geometry_out;
}
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
|
