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
|
// 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/Iso_rectangle_2_Line_2.h $
// $Id: include/CGAL/Intersections_2/Iso_rectangle_2_Line_2.h 08b27d3db14 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Geert-Jan Giezeman
#ifndef CGAL_INTERSECTIONS_2_ISO_RECTANGLE_2_LINE_2_H
#define CGAL_INTERSECTIONS_2_ISO_RECTANGLE_2_LINE_2_H
#include <CGAL/disable_warnings.h>
#include <CGAL/Line_2.h>
#include <CGAL/Iso_rectangle_2.h>
#include <CGAL/kernel_assertions.h>
#include <CGAL/number_utils.h>
#include <CGAL/Intersection_traits_2.h>
namespace CGAL {
namespace Intersections {
namespace internal {
template <class K>
class Line_2_Iso_rectangle_2_pair {
public:
enum Intersection_results {NO_INTERSECTION, POINT, SEGMENT, UNKNOWN};
Line_2_Iso_rectangle_2_pair(typename K::Line_2 const *line,
typename K::Iso_rectangle_2 const *iso)
: _ref_point(line->point()),
_dir(line->direction().to_vector()),
_isomin((iso->min)()),
_isomax((iso->max)()) {}
Intersection_results intersection_type() const;
typename K::Point_2 intersection_point() const;
typename K::Segment_2 intersection_segment() const;
protected:
mutable Intersection_results _result = UNKNOWN;
mutable typename K::FT _min, _max;
typename K::Point_2 _ref_point;
typename K::Vector_2 _dir;
typename K::Point_2 _isomin;
typename K::Point_2 _isomax;
};
template <class K>
inline
typename K::Boolean
do_intersect(const typename K::Line_2& l,
const typename K::Iso_rectangle_2& ir,
const K&)
{
typedef Line_2_Iso_rectangle_2_pair<K> pair_t;
pair_t pair(&l, &ir);
return pair.intersection_type() != pair_t::NO_INTERSECTION;
}
template <class K>
inline
typename K::Boolean
do_intersect(const typename K::Iso_rectangle_2& ir,
const typename K::Line_2& l,
const K& k)
{
return internal::do_intersect(l, ir, k);
}
template <class K>
typename Line_2_Iso_rectangle_2_pair<K>::Intersection_results
Line_2_Iso_rectangle_2_pair<K>::intersection_type() const
{
//typedef typename K::Line_2 line_t;
if (_result!=UNKNOWN)
return _result;
// The non const this pointer is used to cast away const.
typedef typename K::FT FT;
typedef typename K::RT RT;
bool all_values = true;
typename K::Construct_cartesian_const_iterator_2 construct_cccit;
typename K::Cartesian_const_iterator_2 ref_point_it = construct_cccit(_ref_point);
typename K::Cartesian_const_iterator_2 end = construct_cccit(_ref_point, 0);
typename K::Cartesian_const_iterator_2 isomin_it = construct_cccit(_isomin);
typename K::Cartesian_const_iterator_2 isomax_it = construct_cccit(_isomax);
for (unsigned int i=0; ref_point_it != end; ++i, ++ref_point_it, ++isomin_it, ++isomax_it) {
if (_dir.homogeneous(i) == RT(0)) {
if (*ref_point_it < *isomin_it) {
_result = NO_INTERSECTION;
return NO_INTERSECTION;
}
if (*ref_point_it > *isomax_it) {
_result = NO_INTERSECTION;
return NO_INTERSECTION;
}
} else {
FT newmin, newmax;
if (_dir.homogeneous(i) > RT(0)) {
newmin = (*isomin_it - *ref_point_it) /
_dir.cartesian(i);
newmax = (*isomax_it - *ref_point_it) /
_dir.cartesian(i);
} else {
newmin = (*isomax_it - *ref_point_it) /
_dir.cartesian(i);
newmax = (*isomin_it - *ref_point_it) /
_dir.cartesian(i);
}
if (all_values) {
_min = newmin;
_max = newmax;
} else {
if (newmin > _min)
_min = newmin;
if (newmax < _max)
_max = newmax;
if (_max < _min) {
_result = NO_INTERSECTION;
return NO_INTERSECTION;
}
}
all_values = false;
}
}
CGAL_kernel_assertion(!all_values);
if (_max == _min) {
_result = POINT;
return POINT;
}
_result = SEGMENT;
return SEGMENT;
}
template <class K>
typename K::Point_2
Line_2_Iso_rectangle_2_pair<K>::
intersection_point() const
{
typename K::Construct_translated_point_2 translated_point;
typename K::Construct_scaled_vector_2 construct_scaled_vector;
if (_result==UNKNOWN)
intersection_type();
CGAL_kernel_assertion(_result == POINT);
return translated_point(_ref_point, construct_scaled_vector(_dir, _min));
}
template <class K>
typename K::Segment_2
Line_2_Iso_rectangle_2_pair<K>::
intersection_segment() const
{
typename K::Construct_segment_2 construct_segment_2;
typename K::Construct_translated_point_2 translated_point;
typename K::Construct_scaled_vector_2 construct_scaled_vector;
if (_result==UNKNOWN)
intersection_type();
CGAL_kernel_assertion(_result == SEGMENT);
return construct_segment_2(translated_point(_ref_point, construct_scaled_vector(_dir,_min)),
translated_point(_ref_point, construct_scaled_vector(_dir,_max)));
}
template <class K>
typename CGAL::Intersection_traits
<K, typename K::Line_2, typename K::Iso_rectangle_2>::result_type
intersection(const typename K::Line_2 &line,
const typename K::Iso_rectangle_2 &iso,
const K&)
{
typedef Line_2_Iso_rectangle_2_pair<K> is_t;
is_t ispair(&line, &iso);
switch (ispair.intersection_type()) {
case is_t::NO_INTERSECTION:
default:
return intersection_return<typename K::Intersect_2, typename K::Line_2, typename K::Iso_rectangle_2>();
case is_t::POINT:
return intersection_return<typename K::Intersect_2, typename K::Line_2, typename K::Iso_rectangle_2>(ispair.intersection_point());
case is_t::SEGMENT:
return intersection_return<typename K::Intersect_2, typename K::Line_2, typename K::Iso_rectangle_2>(ispair.intersection_segment());
}
}
template <class K>
inline
typename CGAL::Intersection_traits
<K, typename K::Line_2, typename K::Iso_rectangle_2>::result_type
intersection(const typename K::Iso_rectangle_2 &iso,
const typename K::Line_2 &line,
const K& k)
{
return internal::intersection(line, iso, k);
}
} // namespace internal
} // namespace Intersections
CGAL_INTERSECTION_FUNCTION(Line_2, Iso_rectangle_2, 2)
CGAL_DO_INTERSECT_FUNCTION(Line_2, Iso_rectangle_2, 2)
} //namespace CGAL
#include <CGAL/enable_warnings.h>
#endif // CGAL_INTERSECTIONS_2_ISO_RECTANGLE_2_LINE_2_H
|
