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
|
// Copyright (c) 2000
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1.1/Intersections_2/include/CGAL/Intersections_2/Point_2_Triangle_2.h $
// $Id: include/CGAL/Intersections_2/Point_2_Triangle_2.h 08b27d3db14 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Geert-Jan Giezeman
#ifndef CGAL_INTERSECTIONS_2_POINT_2_TRIANGLE_2_H
#define CGAL_INTERSECTIONS_2_POINT_2_TRIANGLE_2_H
#include <CGAL/Point_2.h>
#include <CGAL/Triangle_2.h>
#include <CGAL/kernel_assertions.h>
#include <CGAL/number_utils.h>
#include <CGAL/Intersections_2/internal/Straight_2.h>
namespace CGAL {
namespace Intersections {
namespace internal {
template <class K>
class Point_2_Triangle_2_pair {
public:
enum Intersection_results {NO_INTERSECTION, POINT, UNKNOWN};
Point_2_Triangle_2_pair(typename K::Point_2 const *pt,
typename K::Triangle_2 const *trian)
: _pt(pt), _trian(trian) {}
Intersection_results intersection_type() const;
typename K::Point_2 intersection_point() const;
protected:
typename K::Point_2 const * _pt;
typename K::Triangle_2 const * _trian;
mutable Intersection_results _result = UNKNOWN;
mutable typename K::Point_2 _intersection_point;
mutable typename K::Point_2 _other_point;
};
template <class K>
inline
typename K::Boolean
do_intersect(const typename K::Point_2& p1,
const typename K::Triangle_2& p2,
const K&)
{
typedef Point_2_Triangle_2_pair<K> pair_t;
pair_t pair(&p1, &p2);
return pair.intersection_type() != pair_t::NO_INTERSECTION;
}
template <class K>
inline
typename K::Boolean
do_intersect(const typename K::Triangle_2& p2,
const typename K::Point_2& p1,
const K& k)
{
return internal::do_intersect(p1, p2, k);
}
template <class K>
typename Point_2_Triangle_2_pair<K>::Intersection_results
Point_2_Triangle_2_pair<K>::intersection_type() const
{
if (_result!=UNKNOWN)
return _result;
// The non const this pointer is used to cast away const.
if (_trian->has_on_unbounded_side(*_pt)) {
_result = NO_INTERSECTION;
} else {
_result = POINT;
}
return _result;
}
template <class K>
typename K::Point_2
Point_2_Triangle_2_pair<K>::
intersection_point() const
{
if (_result==UNKNOWN)
intersection_type();
CGAL_kernel_assertion(_result == POINT);
return *_pt;
}
template <class K>
typename Intersection_traits<K, typename K::Point_2, typename K::Triangle_2>
::result_type
intersection(const typename K::Point_2 &pt,
const typename K::Triangle_2 &tr,
const K&)
{
typedef Point_2_Triangle_2_pair<K> is_t;
is_t ispair(&pt, &tr);
switch (ispair.intersection_type()) {
case is_t::NO_INTERSECTION:
default:
return intersection_return<typename K::Intersect_2, typename K::Point_2, typename K::Triangle_2>();
case is_t::POINT:
return intersection_return<typename K::Intersect_2, typename K::Point_2, typename K::Triangle_2>(pt);
}
}
template <class K>
inline
typename Intersection_traits<K, typename K::Point_2, typename K::Triangle_2>
::result_type
intersection(const typename K::Triangle_2 &tr,
const typename K::Point_2 &pt,
const K&k)
{
return internal::intersection(pt, tr, k);
}
} // namespace internal
} // namespace Intersections
CGAL_INTERSECTION_FUNCTION(Point_2, Triangle_2, 2)
CGAL_DO_INTERSECT_FUNCTION(Point_2, Triangle_2, 2)
} // namespace CGAL
#endif // CGAL_INTERSECTIONS_2_POINT_2_TRIANGLE_2_H
|
