Bullet Collision Detection & Physics Library
btTriangleShape.h
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1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org
4 
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages arising from the use of this software.
7 Permission is granted to anyone to use this software for any purpose,
8 including commercial applications, and to alter it and redistribute it freely,
9 subject to the following restrictions:
10 
11 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15 
16 #ifndef BT_OBB_TRIANGLE_MINKOWSKI_H
17 #define BT_OBB_TRIANGLE_MINKOWSKI_H
18 
19 #include "btConvexShape.h"
20 #include "btBoxShape.h"
21 
24 {
25 public:
27 
28  btVector3 m_vertices1[3];
29 
30  virtual int getNumVertices() const
31  {
32  return 3;
33  }
34 
35  btVector3& getVertexPtr(int index)
36  {
37  return m_vertices1[index];
38  }
39 
40  const btVector3& getVertexPtr(int index) const
41  {
42  return m_vertices1[index];
43  }
44  virtual void getVertex(int index, btVector3& vert) const
45  {
46  vert = m_vertices1[index];
47  }
48 
49  virtual int getNumEdges() const
50  {
51  return 3;
52  }
53 
54  virtual void getEdge(int i, btVector3& pa, btVector3& pb) const
55  {
56  getVertex(i, pa);
57  getVertex((i + 1) % 3, pb);
58  }
59 
60  virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const
61  {
62  // btAssert(0);
63  getAabbSlow(t, aabbMin, aabbMax);
64  }
65 
67  {
68  btVector3 dots = dir.dot3(m_vertices1[0], m_vertices1[1], m_vertices1[2]);
69  return m_vertices1[dots.maxAxis()];
70  }
71 
72  virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors, btVector3* supportVerticesOut, int numVectors) const
73  {
74  for (int i = 0; i < numVectors; i++)
75  {
76  const btVector3& dir = vectors[i];
77  btVector3 dots = dir.dot3(m_vertices1[0], m_vertices1[1], m_vertices1[2]);
78  supportVerticesOut[i] = m_vertices1[dots.maxAxis()];
79  }
80  }
81 
83  {
84  m_shapeType = TRIANGLE_SHAPE_PROXYTYPE;
85  }
86 
88  {
89  m_shapeType = TRIANGLE_SHAPE_PROXYTYPE;
90  m_vertices1[0] = p0;
91  m_vertices1[1] = p1;
92  m_vertices1[2] = p2;
93  }
94 
95  virtual void getPlane(btVector3 & planeNormal, btVector3 & planeSupport, int i) const
96  {
97  getPlaneEquation(i, planeNormal, planeSupport);
98  }
99 
100  virtual int getNumPlanes() const
101  {
102  return 1;
103  }
104 
105  void calcNormal(btVector3 & normal) const
106  {
107  normal = (m_vertices1[1] - m_vertices1[0]).cross(m_vertices1[2] - m_vertices1[0]);
108  normal.normalize();
109  }
110 
111  virtual void getPlaneEquation(int i, btVector3& planeNormal, btVector3& planeSupport) const
112  {
113  (void)i;
114  calcNormal(planeNormal);
115  planeSupport = m_vertices1[0];
116  }
117 
118  virtual void calculateLocalInertia(btScalar mass, btVector3 & inertia) const
119  {
120  (void)mass;
121  btAssert(0);
122  inertia.setValue(btScalar(0.), btScalar(0.), btScalar(0.));
123  }
124 
125  virtual bool isInside(const btVector3& pt, btScalar tolerance) const
126  {
127  btVector3 normal;
128  calcNormal(normal);
129  //distance to plane
130  btScalar dist = pt.dot(normal);
131  btScalar planeconst = m_vertices1[0].dot(normal);
132  dist -= planeconst;
133  if (dist >= -tolerance && dist <= tolerance)
134  {
135  //inside check on edge-planes
136  int i;
137  for (i = 0; i < 3; i++)
138  {
139  btVector3 pa, pb;
140  getEdge(i, pa, pb);
141  btVector3 edge = pb - pa;
142  btVector3 edgeNormal = edge.cross(normal);
143  edgeNormal.normalize();
144  btScalar dist = pt.dot(edgeNormal);
145  btScalar edgeConst = pa.dot(edgeNormal);
146  dist -= edgeConst;
147  if (dist < -tolerance)
148  return false;
149  }
150 
151  return true;
152  }
153 
154  return false;
155  }
156  //debugging
157  virtual const char* getName() const
158  {
159  return "Triangle";
160  }
161 
163  {
164  return 2;
165  }
166 
167  virtual void getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
168  {
169  calcNormal(penetrationVector);
170  if (index)
171  penetrationVector *= btScalar(-1.);
172  }
173 };
174 
175 #endif //BT_OBB_TRIANGLE_MINKOWSKI_H
@ TRIANGLE_SHAPE_PROXYTYPE
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:314
#define ATTRIBUTE_ALIGNED16(a)
Definition: btScalar.h:99
#define btAssert(x)
Definition: btScalar.h:153
The btPolyhedralConvexShape is an internal interface class for polyhedral convex shapes.
The btTransform class supports rigid transforms with only translation and rotation and no scaling/she...
Definition: btTransform.h:30
virtual void getEdge(int i, btVector3 &pa, btVector3 &pb) const
virtual int getNumPlanes() const
virtual void getPreferredPenetrationDirection(int index, btVector3 &penetrationVector) const
const btVector3 & getVertexPtr(int index) const
btVector3 & getVertexPtr(int index)
virtual bool isInside(const btVector3 &pt, btScalar tolerance) const
virtual int getNumEdges() const
virtual void getVertex(int index, btVector3 &vert) const
btVector3 localGetSupportingVertexWithoutMargin(const btVector3 &dir) const
btTriangleShape(const btVector3 &p0, const btVector3 &p1, const btVector3 &p2)
virtual void getPlane(btVector3 &planeNormal, btVector3 &planeSupport, int i) const
virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3 *vectors, btVector3 *supportVerticesOut, int numVectors) const
virtual void getAabb(const btTransform &t, btVector3 &aabbMin, btVector3 &aabbMax) const
getAabb's default implementation is brute force, expected derived classes to implement a fast dedicat...
virtual int getNumVertices() const
void calcNormal(btVector3 &normal) const
BT_DECLARE_ALIGNED_ALLOCATOR()
virtual void getPlaneEquation(int i, btVector3 &planeNormal, btVector3 &planeSupport) const
virtual const char * getName() const
virtual void calculateLocalInertia(btScalar mass, btVector3 &inertia) const
virtual int getNumPreferredPenetrationDirections() const
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:82
btVector3 & normalize()
Normalize this vector x^2 + y^2 + z^2 = 1.
Definition: btVector3.h:303
btVector3 cross(const btVector3 &v) const
Return the cross product between this and another vector.
Definition: btVector3.h:380
btScalar dot(const btVector3 &v) const
Return the dot product.
Definition: btVector3.h:229
btVector3 dot3(const btVector3 &v0, const btVector3 &v1, const btVector3 &v2) const
Definition: btVector3.h:720
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
int maxAxis() const
Return the axis with the largest value Note return values are 0,1,2 for x, y, or z.
Definition: btVector3.h:477