liuxiaolong
2021-07-20 232227035c8d6a31eaaf193863cbadda949c08fd
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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
// Boost.Geometry (aka GGL, Generic Geometry Library)
 
// Copyright (c) 2014-2020, Oracle and/or its affiliates.
 
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
 
// Licensed under the Boost Software License version 1.0.
// http://www.boost.org/users/license.html
 
#ifndef BOOST_GEOMETRY_STRATEGIES_COMPARABLE_DISTANCE_RESULT_HPP
#define BOOST_GEOMETRY_STRATEGIES_COMPARABLE_DISTANCE_RESULT_HPP
 
 
#include <boost/variant/variant_fwd.hpp>
 
#include <boost/geometry/algorithms/detail/distance/default_strategies.hpp>
#include <boost/geometry/core/point_type.hpp>
#include <boost/geometry/strategies/default_strategy.hpp>
#include <boost/geometry/strategies/distance.hpp>
#include <boost/geometry/util/select_most_precise.hpp>
#include <boost/geometry/util/sequence.hpp>
#include <boost/geometry/util/type_traits.hpp>
 
 
namespace boost { namespace geometry
{
 
namespace resolve_strategy
{
    
template
<
    typename Geometry1, typename Geometry2, typename Strategy,
    bool AreGeometries = (util::is_geometry<Geometry1>::value
                       && util::is_geometry<Geometry2>::value)
>
struct comparable_distance_result
    : strategy::distance::services::return_type
        <
            typename strategy::distance::services::comparable_type
                <
                    Strategy
                >::type,
            typename point_type<Geometry1>::type,
            typename point_type<Geometry2>::type
        >
{};
 
template <typename Geometry1, typename Geometry2, bool AreGeometries>
struct comparable_distance_result<Geometry1, Geometry2, default_strategy, AreGeometries>
    : comparable_distance_result
        <
            Geometry1,
            Geometry2,
            typename detail::distance::default_strategy
                <
                    Geometry1, Geometry2
                >::type
        >
{};
 
// Workaround for VS2015
#if defined(_MSC_VER) && (_MSC_VER < 1910)
template <typename Geometry1, typename Geometry2, typename Strategy>
struct comparable_distance_result<Geometry1, Geometry2, Strategy, false>
{
    typedef int type;
};
template <typename Geometry1, typename Geometry2>
struct comparable_distance_result<Geometry1, Geometry2, default_strategy, false>
{
    typedef int type;
};
#endif
 
 
} // namespace resolve_strategy
 
 
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace distance
{
 
template <typename Strategy = geometry::default_strategy>
struct more_precise_comparable_distance_result
{
    template <typename Curr, typename Next>
    struct predicate
        : std::is_same
            <
                typename resolve_strategy::comparable_distance_result
                    <
                        typename util::sequence_element<0, Curr>::type,
                        typename util::sequence_element<1, Curr>::type,
                        Strategy
                    >::type,
                typename geometry::select_most_precise
                    <
                        typename resolve_strategy::comparable_distance_result
                            <
                                typename util::sequence_element<0, Curr>::type,
                                typename util::sequence_element<1, Curr>::type,
                                Strategy
                            >::type,
                        typename resolve_strategy::comparable_distance_result
                            <
                                typename util::sequence_element<0, Next>::type,
                                typename util::sequence_element<1, Next>::type,
                                Strategy
                            >::type
                    >::type
            >
    {};
};
 
}} // namespace detail::distance
#endif //DOXYGEN_NO_DETAIL
 
 
namespace resolve_variant
{
 
template <typename Geometry1, typename Geometry2, typename Strategy>
struct comparable_distance_result
    : resolve_strategy::comparable_distance_result
        <
            Geometry1,
            Geometry2,
            Strategy
        >
{};
 
 
template
<
    typename Geometry1,
    BOOST_VARIANT_ENUM_PARAMS(typename T),
    typename Strategy
>
struct comparable_distance_result
    <
        Geometry1, boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Strategy
    >
{
    // Select the most precise distance strategy result type
    //   for all variant type combinations.
    // TODO: We should ignore the combinations that are not valid
    //   but is_implemented is not ready for prime time.
    typedef typename util::select_combination_element
        <
            util::type_sequence<Geometry1>,
            util::type_sequence<BOOST_VARIANT_ENUM_PARAMS(T)>,
            detail::distance::more_precise_comparable_distance_result
                <
                    Strategy
                >::template predicate
        >::type elements;
 
    typedef typename resolve_strategy::comparable_distance_result
        <
            typename util::sequence_element<0, elements>::type,
            typename util::sequence_element<1, elements>::type,
            Strategy
        >::type type;
};
 
 
// Distance arguments are commutative
template
<
    BOOST_VARIANT_ENUM_PARAMS(typename T),
    typename Geometry2,
    typename Strategy
>
struct comparable_distance_result
    <
        boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Geometry2, Strategy
    >
    : public comparable_distance_result
        <
            Geometry2, boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Strategy
        >
{};
 
 
template
<
    BOOST_VARIANT_ENUM_PARAMS(typename T),
    BOOST_VARIANT_ENUM_PARAMS(typename U),
    typename Strategy
>
struct comparable_distance_result
    <
        boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>,
        boost::variant<BOOST_VARIANT_ENUM_PARAMS(U)>,
        Strategy
    >
{
    // Select the most precise distance strategy result type
    //   for all variant type combinations.
    // TODO: We should ignore the combinations that are not valid
    //   but is_implemented is not ready for prime time.
    typedef typename util::select_combination_element
        <
            util::type_sequence<BOOST_VARIANT_ENUM_PARAMS(T)>,
            util::type_sequence<BOOST_VARIANT_ENUM_PARAMS(U)>,
            detail::distance::more_precise_comparable_distance_result
                <
                    Strategy
                >::template predicate
        >::type elements;
 
    typedef typename resolve_strategy::comparable_distance_result
        <
            typename util::sequence_element<0, elements>::type,
            typename util::sequence_element<1, elements>::type,
            Strategy
        >::type type;
};
 
} // namespace resolve_variant
 
 
 
 
 
/*!
\brief Meta-function defining return type of comparable_distance function
\ingroup distance
*/
template
<
    typename Geometry1,
    typename Geometry2 = Geometry1,
    typename Strategy = void
>
struct comparable_distance_result
    : resolve_variant::comparable_distance_result
        <
            Geometry1, Geometry2, Strategy
        >
{};
 
template <typename Geometry1, typename Geometry2>
struct comparable_distance_result<Geometry1, Geometry2, void>
    : comparable_distance_result<Geometry1, Geometry2, default_strategy>
{};
 
 
}} // namespace boost::geometry
 
 
#endif // BOOST_GEOMETRY_STRATEGIES_COMPARABLE_DISTANCE_RESULT_HPP