Bullet Collision Detection & Physics Library
btTriangleShape.h
Go to the documentation of this file.
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 
23 {
24 
25 
26 public:
27 
29 
30  btVector3 m_vertices1[3];
31 
32  virtual int getNumVertices() const
33  {
34  return 3;
35  }
36 
37  btVector3& getVertexPtr(int index)
38  {
39  return m_vertices1[index];
40  }
41 
42  const btVector3& getVertexPtr(int index) const
43  {
44  return m_vertices1[index];
45  }
46  virtual void getVertex(int index,btVector3& vert) const
47  {
48  vert = m_vertices1[index];
49  }
50 
51  virtual int getNumEdges() const
52  {
53  return 3;
54  }
55 
56  virtual void getEdge(int i,btVector3& pa,btVector3& pb) const
57  {
58  getVertex(i,pa);
59  getVertex((i+1)%3,pb);
60  }
61 
62 
63  virtual void getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax)const
64  {
65 // btAssert(0);
66  getAabbSlow(t,aabbMin,aabbMax);
67  }
68 
70  {
71  btVector3 dots = dir.dot3(m_vertices1[0], m_vertices1[1], m_vertices1[2]);
72  return m_vertices1[dots.maxAxis()];
73 
74  }
75 
76  virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const
77  {
78  for (int i=0;i<numVectors;i++)
79  {
80  const btVector3& dir = vectors[i];
81  btVector3 dots = dir.dot3(m_vertices1[0], m_vertices1[1], m_vertices1[2]);
82  supportVerticesOut[i] = m_vertices1[dots.maxAxis()];
83  }
84 
85  }
86 
87  btTriangleShape() : btPolyhedralConvexShape ()
88  {
89  m_shapeType = TRIANGLE_SHAPE_PROXYTYPE;
90  }
91 
92  btTriangleShape(const btVector3& p0,const btVector3& p1,const btVector3& p2) : btPolyhedralConvexShape ()
93  {
94  m_shapeType = TRIANGLE_SHAPE_PROXYTYPE;
95  m_vertices1[0] = p0;
96  m_vertices1[1] = p1;
97  m_vertices1[2] = p2;
98  }
99 
100 
101  virtual void getPlane(btVector3& planeNormal,btVector3& planeSupport,int i) const
102  {
103  getPlaneEquation(i,planeNormal,planeSupport);
104  }
105 
106  virtual int getNumPlanes() const
107  {
108  return 1;
109  }
110 
111  void calcNormal(btVector3& normal) const
112  {
113  normal = (m_vertices1[1]-m_vertices1[0]).cross(m_vertices1[2]-m_vertices1[0]);
114  normal.normalize();
115  }
116 
117  virtual void getPlaneEquation(int i, btVector3& planeNormal,btVector3& planeSupport) const
118  {
119  (void)i;
120  calcNormal(planeNormal);
121  planeSupport = m_vertices1[0];
122  }
123 
124  virtual void calculateLocalInertia(btScalar mass,btVector3& inertia) const
125  {
126  (void)mass;
127  btAssert(0);
128  inertia.setValue(btScalar(0.),btScalar(0.),btScalar(0.));
129  }
130 
131  virtual bool isInside(const btVector3& pt,btScalar tolerance) const
132  {
133  btVector3 normal;
134  calcNormal(normal);
135  //distance to plane
136  btScalar dist = pt.dot(normal);
137  btScalar planeconst = m_vertices1[0].dot(normal);
138  dist -= planeconst;
139  if (dist >= -tolerance && dist <= tolerance)
140  {
141  //inside check on edge-planes
142  int i;
143  for (i=0;i<3;i++)
144  {
145  btVector3 pa,pb;
146  getEdge(i,pa,pb);
147  btVector3 edge = pb-pa;
148  btVector3 edgeNormal = edge.cross(normal);
149  edgeNormal.normalize();
150  btScalar dist = pt.dot( edgeNormal);
151  btScalar edgeConst = pa.dot(edgeNormal);
152  dist -= edgeConst;
153  if (dist < -tolerance)
154  return false;
155  }
156 
157  return true;
158  }
159 
160  return false;
161  }
162  //debugging
163  virtual const char* getName()const
164  {
165  return "Triangle";
166  }
167 
169  {
170  return 2;
171  }
172 
173  virtual void getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
174  {
175  calcNormal(penetrationVector);
176  if (index)
177  penetrationVector *= btScalar(-1.);
178  }
179 
180 
181 };
182 
183 #endif //BT_OBB_TRIANGLE_MINKOWSKI_H
184 
virtual void getPlaneEquation(int i, btVector3 &planeNormal, btVector3 &planeSupport) const
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
float dist(const Point3 &pnt0, const Point3 &pnt1)
btTriangleShape(const btVector3 &p0, const btVector3 &p1, const btVector3 &p2)
#define btAssert(x)
Definition: btScalar.h:101
virtual int getNumPreferredPenetrationDirections() const
btScalar dot(const btVector3 &v) const
Return the dot product.
Definition: btVector3.h:235
btVector3 & normalize()
Normalize this vector x^2 + y^2 + z^2 = 1.
Definition: btVector3.h:297
void calcNormal(btVector3 &normal) const
virtual void getPlane(btVector3 &planeNormal, btVector3 &planeSupport, int i) const
virtual void getVertex(int index, btVector3 &vert) const
const btVector3 & getVertexPtr(int index) const
btVector3 & getVertexPtr(int index)
btVector3 cross(const btVector3 &v) const
Return the cross product between this and another vector.
Definition: btVector3.h:377
The btPolyhedralConvexShape is an internal interface class for polyhedral convex shapes.
virtual void calculateLocalInertia(btScalar mass, btVector3 &inertia) const
virtual int getNumEdges() const
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:83
#define ATTRIBUTE_ALIGNED16(a)
Definition: btScalar.h:59
The btTransform class supports rigid transforms with only translation and rotation and no scaling/she...
Definition: btTransform.h:34
virtual int getNumVertices() const
virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3 *vectors, btVector3 *supportVerticesOut, int numVectors) const
static float4 cross(const float4 &a, const float4 &b)
#define BT_DECLARE_ALIGNED_ALLOCATOR()
Definition: btScalar.h:357
btVector3 dot3(const btVector3 &v0, const btVector3 &v1, const btVector3 &v2) const
Definition: btVector3.h:718
virtual void getEdge(int i, btVector3 &pa, btVector3 &pb) 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 bool isInside(const btVector3 &pt, btScalar tolerance) const
virtual int getNumPlanes() const
btVector3 localGetSupportingVertexWithoutMargin(const btVector3 &dir) const
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:266
virtual const char * getName() const
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:475
virtual void getPreferredPenetrationDirection(int index, btVector3 &penetrationVector) const