WFMath  1.0.2
ball.h
1 // ball.h (A n-dimensional ball)
2 //
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23 
24 // Author: Ron Steinke
25 
26 #ifndef WFMATH_BALL_H
27 #define WFMATH_BALL_H
28 
29 #include <wfmath/point.h>
30 #include <wfmath/intersect_decls.h>
31 
32 namespace WFMath {
33 
34 template<int dim> class Ball;
35 
37 template<int dim, template<class, class> class container>
38 Ball<dim> BoundingSphere(const container<Point<dim>, std::allocator<Point<dim> > >& c);
40 template<int dim, template<class, class> class container>
41 Ball<dim> BoundingSphereSloppy(const container<Point<dim>, std::allocator<Point<dim> > >& c);
42 
43 template<int dim>
44 std::ostream& operator<<(std::ostream& os, const Ball<dim>& m);
45 template<int dim>
46 std::istream& operator>>(std::istream& is, Ball<dim>& m);
47 
49 
59 template<int dim = 3>
60 class Ball
61 {
62  public:
64  Ball() : m_center(), m_radius(0.f) {}
67  : m_center(center), m_radius(radius) { if (radius < 0) m_center.setValid(false); }
69  Ball(const Ball& b) : m_center(b.m_center), m_radius(b.m_radius) {}
71  explicit Ball(const AtlasInType& a);
72 
73  ~Ball() {}
74 
75  friend std::ostream& operator<< <dim>(std::ostream& os, const Ball& b);
76  friend std::istream& operator>> <dim>(std::istream& is, Ball& b);
77 
79  AtlasOutType toAtlas() const;
81  void fromAtlas(const AtlasInType& a);
82 
83  Ball& operator=(const Ball& b)
84  {m_radius = b.m_radius; m_center = b.m_center; return *this;}
85 
86  bool isEqualTo(const Ball& b, CoordType epsilon = numeric_constants<CoordType>::epsilon()) const;
87 
88  bool operator==(const Ball& b) const {return isEqualTo(b);}
89  bool operator!=(const Ball& b) const {return !isEqualTo(b);}
90 
91  bool isValid() const {return m_center.isValid();}
92 
93  // Descriptive characteristics
94 
95  size_t numCorners() const {return 0;}
96  // This next function exists so that Ball can be used by code
97  // that finds the number of corners with numCorners(), and does something
98  // with each corner with getCorner(). No idea how useful that is, but
99  // it's not a particularly complicated function to write.
100  Point<dim> getCorner(size_t) const {return m_center;}
101  Point<dim> getCenter() const {return m_center;}
102 
104  const Point<dim>& center() const {return m_center;}
106  Point<dim>& center() {return m_center;}
108  CoordType radius() const {return m_radius;}
110  CoordType& radius() {return m_radius;}
111 
112  // Movement functions
113 
114  Ball& shift(const Vector<dim>& v) {m_center += v; return *this;}
115  Ball& moveCornerTo(const Point<dim>&, size_t) {return *this;}
116  Ball& moveCenterTo(const Point<dim>& p) {m_center = p; return *this;}
117 
118  Ball& rotateCorner(const RotMatrix<dim>&, size_t) {return *this;}
119  Ball& rotateCenter(const RotMatrix<dim>&) {return *this;}
120  Ball& rotatePoint(const RotMatrix<dim>& m, const Point<dim>& p)
121  {m_center.rotate(m, p); return *this;}
122 
123  // 3D rotation function
124  Ball& rotateCorner(const Quaternion&, size_t corner);
125  Ball& rotateCenter(const Quaternion&);
126  Ball& rotatePoint(const Quaternion& q, const Point<dim>& p);
127 
128  // Intersection functions
129 
130  AxisBox<dim> boundingBox() const;
131  Ball boundingSphere() const {return *this;}
132  Ball boundingSphereSloppy() const {return *this;}
133 
134  Ball toParentCoords(const Point<dim>& origin,
135  const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
136  {return Ball(m_center.toParentCoords(origin, rotation), m_radius);}
137  Ball toParentCoords(const AxisBox<dim>& coords) const
138  {return Ball(m_center.toParentCoords(coords), m_radius);}
139  Ball toParentCoords(const RotBox<dim>& coords) const
140  {return Ball(m_center.toParentCoords(coords), m_radius);}
141 
142  // toLocal is just like toParent, expect we reverse the order of
143  // translation and rotation and use the opposite sense of the rotation
144  // matrix
145 
146  Ball toLocalCoords(const Point<dim>& origin,
147  const RotMatrix<dim>& rotation = RotMatrix<dim>().identity()) const
148  {return Ball(m_center.toLocalCoords(origin, rotation), m_radius);}
149  Ball toLocalCoords(const AxisBox<dim>& coords) const
150  {return Ball(m_center.toLocalCoords(coords), m_radius);}
151  Ball toLocalCoords(const RotBox<dim>& coords) const
152  {return Ball(m_center.toLocalCoords(coords), m_radius);}
153 
154  // 3D only
155  Ball toParentCoords(const Point<dim>& origin, const Quaternion& rotation) const;
156  Ball toLocalCoords(const Point<dim>& origin, const Quaternion& rotation) const;
157 
158  friend bool Intersect<dim>(const Ball& b, const Point<dim>& p, bool proper);
159  friend bool Contains<dim>(const Point<dim>& p, const Ball& b, bool proper);
160 
161  friend bool Intersect<dim>(const Ball& b, const AxisBox<dim>& a, bool proper);
162  friend bool Contains<dim>(const Ball& b, const AxisBox<dim>& a, bool proper);
163  friend bool Contains<dim>(const AxisBox<dim>& a, const Ball& b, bool proper);
164 
165  friend bool Intersect<dim>(const Ball& b1, const Ball& b2, bool proper);
166  friend bool Contains<dim>(const Ball& outer, const Ball& inner, bool proper);
167 
168  friend bool Intersect<dim>(const Segment<dim>& s, const Ball& b, bool proper);
169  friend bool Contains<dim>(const Segment<dim>& s, const Ball& b, bool proper);
170 
171  friend bool Intersect<dim>(const RotBox<dim>& r, const Ball& b, bool proper);
172  friend bool Contains<dim>(const RotBox<dim>& r, const Ball& b, bool proper);
173  friend bool Contains<dim>(const Ball& b, const RotBox<dim>& r, bool proper);
174 
175  friend bool Intersect<dim>(const Polygon<dim>& p, const Ball& b, bool proper);
176  friend bool Contains<dim>(const Polygon<dim>& p, const Ball& b, bool proper);
177  friend bool Contains<dim>(const Ball& b, const Polygon<dim>& p, bool proper);
178 
179  private:
180 
181  Point<dim> m_center;
182  CoordType m_radius;
183 };
184 
185 template<int dim>
186 inline bool Ball<dim>::isEqualTo(const Ball<dim>& b, CoordType epsilon) const
187 {
188  return Equal(m_center, b.m_center, epsilon)
189  && Equal(m_radius, b.m_radius, epsilon);
190 }
191 
192 } // namespace WFMath
193 
194 #endif // WFMATH_BALL_H
bool Equal(const C &c1, const C &c2, CoordType epsilon=numeric_constants< CoordType >::epsilon())
Test for equality up to precision epsilon.
Definition: const.h:158
Generic library namespace.
Definition: atlasconv.h:45
Ball(const Ball &b)
construct a copy of a ball
Definition: ball.h:69
void fromAtlas(const AtlasInType &a)
Set the box&#39;s value to that given by an Atlas object.
Definition: atlasconv.h:248
Point< dim > & center()
get the center of the ball
Definition: ball.h:106
Ball< dim > BoundingSphereSloppy(const container< Point< dim >, std::allocator< Point< dim > > > &c)
get a bounding sphere for a set of points
Definition: ball_funcs.h:92
CoordType & radius()
get the radius of the ball
Definition: ball.h:110
AtlasOutType toAtlas() const
Create an Atlas object from the box.
Definition: atlasconv.h:272
A dim dimensional vector.
Definition: const.h:55
CoordType radius() const
get the radius of the ball
Definition: ball.h:108
Ball()
construct an uninitialized ball
Definition: ball.h:64
float CoordType
Basic floating point type.
Definition: const.h:140
const Point< dim > & center() const
get the center of the ball
Definition: ball.h:104
Ball< dim > BoundingSphere(const container< Point< dim >, std::allocator< Point< dim > > > &c)
get the minimal bounding sphere for a set of points
Definition: ball_funcs.h:57
A dim dimensional point.
Definition: const.h:50
Ball(const Point< dim > &center, CoordType radius)
construct a ball with the given center and radius
Definition: ball.h:66
A dim dimensional ball.
Definition: ball.h:34