wfmath 1.0.3
A math library for the Worldforge system.
segment.h
1// segment.h (A line segment)
2//
3// The WorldForge Project
4// Copyright (C) 2000, 2001 The WorldForge Project
5//
6// This program is free software; you can redistribute it and/or modify
7// it under the terms of the GNU General Public License as published by
8// the Free Software Foundation; either version 2 of the License, or
9// (at your option) any later version.
10//
11// This program is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15//
16// You should have received a copy of the GNU General Public License
17// along with this program; if not, write to the Free Software
18// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19//
20// For information about WorldForge and its authors, please contact
21// the Worldforge Web Site at http://www.worldforge.org.
22//
23
24// Author: Ron Steinke
25
26#ifndef WFMATH_SEGMENT_H
27#define WFMATH_SEGMENT_H
28
29#include <wfmath/point.h>
30#include <wfmath/intersect_decls.h>
31
32namespace WFMath {
33
34template<int dim>
35std::ostream& operator<<(std::ostream& os, const Segment<dim>& s);
36template<int dim>
37std::istream& operator>>(std::istream& is, Segment<dim>& s);
38
40
44template<int dim = 3>
46{
47 public:
49 Segment() : m_p1{}, m_p2{} {}
51 Segment(const Point<dim>& p1, const Point<dim>& p2) : m_p1(p1), m_p2(p2) {}
53 Segment(const Segment& s) = default;
54
55 ~Segment() = default;
56
57 friend std::ostream& operator<< <dim>(std::ostream& os, const Segment& s);
58 friend std::istream& operator>> <dim>(std::istream& is, Segment& s);
59
60 Segment& operator=(const Segment& s) = default;
61
62 bool isEqualTo(const Segment& s, CoordType epsilon = numeric_constants<CoordType>::epsilon()) const;
63
64 bool operator==(const Segment& b) const {return isEqualTo(b);}
65 bool operator!=(const Segment& b) const {return !isEqualTo(b);}
66
67 bool isValid() const {return m_p1.isValid() && m_p2.isValid();}
68
69 // Descriptive characteristics
70
71 size_t numCorners() const {return 2;}
72 Point<dim> getCorner(size_t i) const {return i ? m_p2 : m_p1;}
73 Point<dim> getCenter() const {return Midpoint(m_p1, m_p2);}
74
76 const Point<dim>& endpoint(const int i) const {return i ? m_p2 : m_p1;}
78 Point<dim>& endpoint(const int i) {return i ? m_p2 : m_p1;}
79
80 // Movement functions
81
82 Segment& shift(const Vector<dim>& v)
83 {m_p1 += v; m_p2 += v; return *this;}
84 Segment& moveCornerTo(const Point<dim>& p, size_t corner);
85 Segment& moveCenterTo(const Point<dim>& p)
86 {return shift(p - getCenter());}
87
88 Segment& rotateCorner(const RotMatrix<dim>& m, size_t corner);
89 Segment& rotateCenter(const RotMatrix<dim>& m)
90 {rotatePoint(m, getCenter()); return *this;}
91 Segment<dim>& rotatePoint(const RotMatrix<dim>& m, const Point<dim>& p)
92 {m_p1.rotate(m, p); m_p2.rotate(m, p); return *this;}
93
94 // 3D rotation functions
95 Segment& rotateCorner(const Quaternion& q, size_t corner);
96 Segment& rotateCenter(const Quaternion& q);
97 Segment& rotatePoint(const Quaternion& q, const Point<dim>& p);
98
99 // Intersection functions
100
101 AxisBox<dim> boundingBox() const {return AxisBox<dim>(m_p1, m_p2);}
102 Ball<dim> boundingSphere() const
103 {return Ball<dim>(getCenter(), Distance(m_p1, m_p2) / 2);}
104 Ball<dim> boundingSphereSloppy() const
105 {return Ball<dim>(getCenter(), SloppyDistance(m_p1, m_p2) / 2);}
106
107 Segment toParentCoords(const Point<dim>& origin,
108 const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
109 {return Segment(m_p1.toParentCoords(origin, rotation),
110 m_p2.toParentCoords(origin, rotation));}
111 Segment toParentCoords(const AxisBox<dim>& coords) const
112 {return Segment(m_p1.toParentCoords(coords), m_p2.toParentCoords(coords));}
113 Segment toParentCoords(const RotBox<dim>& coords) const
114 {return Segment(m_p1.toParentCoords(coords), m_p2.toParentCoords(coords));}
115
116 // toLocal is just like toParent, expect we reverse the order of
117 // translation and rotation and use the opposite sense of the rotation
118 // matrix
119
120 Segment toLocalCoords(const Point<dim>& origin,
121 const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
122 {return Segment(m_p1.toLocalCoords(origin, rotation),
123 m_p2.toLocalCoords(origin, rotation));}
124 Segment toLocalCoords(const AxisBox<dim>& coords) const
125 {return Segment(m_p1.toLocalCoords(coords), m_p2.toLocalCoords(coords));}
126 Segment toLocalCoords(const RotBox<dim>& coords) const
127 {return Segment(m_p1.toLocalCoords(coords), m_p2.toLocalCoords(coords));}
128
129 // 3D only
130 Segment toParentCoords(const Point<dim>& origin,
131 const Quaternion& rotation) const;
132 Segment toLocalCoords(const Point<dim>& origin,
133 const Quaternion& rotation) const;
134
135 friend bool Intersect<dim>(const Segment& s, const Point<dim>& p, bool proper);
136 friend bool Contains<dim>(const Point<dim>& p, const Segment& s, bool proper);
137
138 friend bool Intersect<dim>(const Segment& s, const AxisBox<dim>& b, bool proper);
139 friend bool Contains<dim>(const AxisBox<dim>& b, const Segment& s, bool proper);
140
141 friend bool Intersect<dim>(const Segment& s, const Ball<dim>& b, bool proper);
142 friend bool Contains<dim>(const Ball<dim>& b, const Segment& s, bool proper);
143
144 friend bool Intersect<dim>(const Segment& s1, const Segment& s2, bool proper);
145 friend bool Contains<dim>(const Segment& s1, const Segment& s2, bool proper);
146
147 friend bool Intersect<dim>(const RotBox<dim>& r, const Segment& s, bool proper);
148 friend bool Contains<dim>(const RotBox<dim>& r, const Segment& s, bool proper);
149 friend bool Contains<dim>(const Segment& s, const RotBox<dim>& r, bool proper);
150
151 friend bool Intersect<dim>(const Polygon<dim>& r, const Segment& s, bool proper);
152 friend bool Contains<dim>(const Polygon<dim>& p, const Segment& s, bool proper);
153 friend bool Contains<dim>(const Segment& s, const Polygon<dim>& p, bool proper);
154
155 private:
156
157 Point<dim> m_p1, m_p2;
158};
159
160template<int dim>
161inline bool Segment<dim>::isEqualTo(const Segment<dim>& s,
162 CoordType epsilon) const
163{
164 return Equal(m_p1, s.m_p1, epsilon)
165 && Equal(m_p2, s.m_p2, epsilon);
166}
167
168} // namespace WFMath
169
170#endif // WFMATH_SEGMENT_H
Point & rotate(const RotMatrix< dim > &m, const Point &p)
Rotate about point p.
Definition: point.h:146
A line segment embedded in dim dimensions.
Definition: segment.h:46
const Point< dim > & endpoint(const int i) const
get one end of the segment
Definition: segment.h:76
Segment()
construct an uninitialized segment
Definition: segment.h:49
Segment(const Point< dim > &p1, const Point< dim > &p2)
construct a segment with endpoints p1 and p2
Definition: segment.h:51
Point< dim > & endpoint(const int i)
get one end of the segment
Definition: segment.h:78
Segment(const Segment &s)=default
construct a copy of a segment
Generic library namespace.
Definition: shape.h:41
double CoordType
Basic floating point type.
Definition: const.h:140
Point< dim > Midpoint(const Point< dim > &p1, const Point< dim > &p2, CoordType dist=0.5)
Definition: point_funcs.h:219