WFMath  1.0.1
segment.h
1 // segment.h (A line segment)
2 //
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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 
32 namespace WFMath {
33 
34 template<int dim>
35 std::ostream& operator<<(std::ostream& os, const Segment<dim>& s);
36 template<int dim>
37 std::istream& operator>>(std::istream& is, Segment<dim>& s);
38 
40 
44 template<int dim = 3>
45 class Segment
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) : m_p1(s.m_p1), m_p2(s.m_p2) {}
54 
55  ~Segment() {}
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)
61  {m_p1 = s.m_p1; m_p2 = s.m_p2; return *this;}
62 
63  bool isEqualTo(const Segment& s, CoordType epsilon = numeric_constants<CoordType>::epsilon()) const;
64 
65  bool operator==(const Segment& b) const {return isEqualTo(b);}
66  bool operator!=(const Segment& b) const {return !isEqualTo(b);}
67 
68  bool isValid() const {return m_p1.isValid() && m_p2.isValid();}
69 
70  // Descriptive characteristics
71 
72  size_t numCorners() const {return 2;}
73  Point<dim> getCorner(size_t i) const {return i ? m_p2 : m_p1;}
74  Point<dim> getCenter() const {return Midpoint(m_p1, m_p2);}
75 
77  const Point<dim>& endpoint(const int i) const {return i ? m_p2 : m_p1;}
79  Point<dim>& endpoint(const int i) {return i ? m_p2 : m_p1;}
80 
81  // Movement functions
82 
83  Segment& shift(const Vector<dim>& v)
84  {m_p1 += v; m_p2 += v; return *this;}
85  Segment& moveCornerTo(const Point<dim>& p, size_t corner);
86  Segment& moveCenterTo(const Point<dim>& p)
87  {return shift(p - getCenter());}
88 
89  Segment& rotateCorner(const RotMatrix<dim>& m, size_t corner);
90  Segment& rotateCenter(const RotMatrix<dim>& m)
91  {rotatePoint(m, getCenter()); return *this;}
92  Segment<dim>& rotatePoint(const RotMatrix<dim>& m, const Point<dim>& p)
93  {m_p1.rotate(m, p); m_p2.rotate(m, p); return *this;}
94 
95  // 3D rotation functions
96  Segment& rotateCorner(const Quaternion& q, size_t corner);
97  Segment& rotateCenter(const Quaternion& q);
98  Segment& rotatePoint(const Quaternion& q, const Point<dim>& p);
99 
100  // Intersection functions
101 
102  AxisBox<dim> boundingBox() const {return AxisBox<dim>(m_p1, m_p2);}
103  Ball<dim> boundingSphere() const
104  {return Ball<dim>(getCenter(), Distance(m_p1, m_p2) / 2);}
105  Ball<dim> boundingSphereSloppy() const
106  {return Ball<dim>(getCenter(), SloppyDistance(m_p1, m_p2) / 2);}
107 
108  Segment toParentCoords(const Point<dim>& origin,
109  const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
110  {return Segment(m_p1.toParentCoords(origin, rotation),
111  m_p2.toParentCoords(origin, rotation));}
112  Segment toParentCoords(const AxisBox<dim>& coords) const
113  {return Segment(m_p1.toParentCoords(coords), m_p2.toParentCoords(coords));}
114  Segment toParentCoords(const RotBox<dim>& coords) const
115  {return Segment(m_p1.toParentCoords(coords), m_p2.toParentCoords(coords));}
116 
117  // toLocal is just like toParent, expect we reverse the order of
118  // translation and rotation and use the opposite sense of the rotation
119  // matrix
120 
121  Segment toLocalCoords(const Point<dim>& origin,
122  const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
123  {return Segment(m_p1.toLocalCoords(origin, rotation),
124  m_p2.toLocalCoords(origin, rotation));}
125  Segment toLocalCoords(const AxisBox<dim>& coords) const
126  {return Segment(m_p1.toLocalCoords(coords), m_p2.toLocalCoords(coords));}
127  Segment toLocalCoords(const RotBox<dim>& coords) const
128  {return Segment(m_p1.toLocalCoords(coords), m_p2.toLocalCoords(coords));}
129 
130  // 3D only
131  Segment toParentCoords(const Point<dim>& origin,
132  const Quaternion& rotation) const;
133  Segment toLocalCoords(const Point<dim>& origin,
134  const Quaternion& rotation) const;
135 
136  friend bool Intersect<dim>(const Segment& s, const Point<dim>& p, bool proper);
137  friend bool Contains<dim>(const Point<dim>& p, const Segment& s, bool proper);
138 
139  friend bool Intersect<dim>(const Segment& s, const AxisBox<dim>& b, bool proper);
140  friend bool Contains<dim>(const AxisBox<dim>& b, const Segment& s, bool proper);
141 
142  friend bool Intersect<dim>(const Segment& s, const Ball<dim>& b, bool proper);
143  friend bool Contains<dim>(const Ball<dim>& b, const Segment& s, bool proper);
144 
145  friend bool Intersect<dim>(const Segment& s1, const Segment& s2, bool proper);
146  friend bool Contains<dim>(const Segment& s1, const Segment& s2, bool proper);
147 
148  friend bool Intersect<dim>(const RotBox<dim>& r, const Segment& s, bool proper);
149  friend bool Contains<dim>(const RotBox<dim>& r, const Segment& s, bool proper);
150  friend bool Contains<dim>(const Segment& s, const RotBox<dim>& r, bool proper);
151 
152  friend bool Intersect<dim>(const Polygon<dim>& r, const Segment& s, bool proper);
153  friend bool Contains<dim>(const Polygon<dim>& p, const Segment& s, bool proper);
154  friend bool Contains<dim>(const Segment& s, const Polygon<dim>& p, bool proper);
155 
156  private:
157 
158  Point<dim> m_p1, m_p2;
159 };
160 
161 template<int dim>
162 inline bool Segment<dim>::isEqualTo(const Segment<dim>& s,
163  CoordType epsilon) const
164 {
165  return Equal(m_p1, s.m_p1, epsilon)
166  && Equal(m_p2, s.m_p2, epsilon);
167 }
168 
169 } // namespace WFMath
170 
171 #endif // WFMATH_SEGMENT_H