Bullet Collision Detection & Physics Library
btBox2dShape.h
Go to the documentation of this file.
1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
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_BOX_2D_SHAPE_H
17 #define BT_OBB_BOX_2D_SHAPE_H
18 
22 #include "LinearMath/btVector3.h"
23 #include "LinearMath/btMinMax.h"
24 
28 {
29  //btVector3 m_boxHalfExtents1; //use m_implicitShapeDimensions instead
30 
32  btVector3 m_vertices[4];
33  btVector3 m_normals[4];
34 
35 public:
37 
39  {
40  btVector3 halfExtents = getHalfExtentsWithoutMargin();
41  btVector3 margin(getMargin(), getMargin(), getMargin());
42  halfExtents += margin;
43  return halfExtents;
44  }
45 
47  {
48  return m_implicitShapeDimensions; //changed in Bullet 2.63: assume the scaling and margin are included
49  }
50 
51  virtual btVector3 localGetSupportingVertex(const btVector3& vec) const
52  {
53  btVector3 halfExtents = getHalfExtentsWithoutMargin();
54  btVector3 margin(getMargin(), getMargin(), getMargin());
55  halfExtents += margin;
56 
57  return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
58  btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
59  btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
60  }
61 
63  {
64  const btVector3& halfExtents = getHalfExtentsWithoutMargin();
65 
66  return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
67  btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
68  btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
69  }
70 
71  virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors, btVector3* supportVerticesOut, int numVectors) const
72  {
73  const btVector3& halfExtents = getHalfExtentsWithoutMargin();
74 
75  for (int i = 0; i < numVectors; i++)
76  {
77  const btVector3& vec = vectors[i];
78  supportVerticesOut[i].setValue(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
79  btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
80  btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
81  }
82  }
83 
85  btBox2dShape(const btVector3& boxHalfExtents)
87  m_centroid(0, 0, 0)
88  {
89  m_vertices[0].setValue(-boxHalfExtents.getX(), -boxHalfExtents.getY(), 0);
90  m_vertices[1].setValue(boxHalfExtents.getX(), -boxHalfExtents.getY(), 0);
91  m_vertices[2].setValue(boxHalfExtents.getX(), boxHalfExtents.getY(), 0);
92  m_vertices[3].setValue(-boxHalfExtents.getX(), boxHalfExtents.getY(), 0);
93 
94  m_normals[0].setValue(0, -1, 0);
95  m_normals[1].setValue(1, 0, 0);
96  m_normals[2].setValue(0, 1, 0);
97  m_normals[3].setValue(-1, 0, 0);
98 
99  btScalar minDimension = boxHalfExtents.getX();
100  if (minDimension > boxHalfExtents.getY())
101  minDimension = boxHalfExtents.getY();
102 
103  m_shapeType = BOX_2D_SHAPE_PROXYTYPE;
104  btVector3 margin(getMargin(), getMargin(), getMargin());
105  m_implicitShapeDimensions = (boxHalfExtents * m_localScaling) - margin;
106 
107  setSafeMargin(minDimension);
108  };
109 
110  virtual void setMargin(btScalar collisionMargin)
111  {
112  //correct the m_implicitShapeDimensions for the margin
113  btVector3 oldMargin(getMargin(), getMargin(), getMargin());
114  btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions + oldMargin;
115 
116  btConvexInternalShape::setMargin(collisionMargin);
117  btVector3 newMargin(getMargin(), getMargin(), getMargin());
118  m_implicitShapeDimensions = implicitShapeDimensionsWithMargin - newMargin;
119  }
120  virtual void setLocalScaling(const btVector3& scaling)
121  {
122  btVector3 oldMargin(getMargin(), getMargin(), getMargin());
123  btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions + oldMargin;
124  btVector3 unScaledImplicitShapeDimensionsWithMargin = implicitShapeDimensionsWithMargin / m_localScaling;
125 
127 
128  m_implicitShapeDimensions = (unScaledImplicitShapeDimensionsWithMargin * m_localScaling) - oldMargin;
129  }
130 
131  virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const;
132 
133  virtual void calculateLocalInertia(btScalar mass, btVector3 & inertia) const;
134 
135  int getVertexCount() const
136  {
137  return 4;
138  }
139 
140  virtual int getNumVertices() const
141  {
142  return 4;
143  }
144 
145  const btVector3* getVertices() const
146  {
147  return &m_vertices[0];
148  }
149 
150  const btVector3* getNormals() const
151  {
152  return &m_normals[0];
153  }
154 
155  virtual void getPlane(btVector3 & planeNormal, btVector3 & planeSupport, int i) const
156  {
157  //this plane might not be aligned...
158  btVector4 plane;
159  getPlaneEquation(plane, i);
160  planeNormal = btVector3(plane.getX(), plane.getY(), plane.getZ());
161  planeSupport = localGetSupportingVertex(-planeNormal);
162  }
163 
164  const btVector3& getCentroid() const
165  {
166  return m_centroid;
167  }
168 
169  virtual int getNumPlanes() const
170  {
171  return 6;
172  }
173 
174  virtual int getNumEdges() const
175  {
176  return 12;
177  }
178 
179  virtual void getVertex(int i, btVector3& vtx) const
180  {
181  btVector3 halfExtents = getHalfExtentsWithoutMargin();
182 
183  vtx = btVector3(
184  halfExtents.x() * (1 - (i & 1)) - halfExtents.x() * (i & 1),
185  halfExtents.y() * (1 - ((i & 2) >> 1)) - halfExtents.y() * ((i & 2) >> 1),
186  halfExtents.z() * (1 - ((i & 4) >> 2)) - halfExtents.z() * ((i & 4) >> 2));
187  }
188 
189  virtual void getPlaneEquation(btVector4 & plane, int i) const
190  {
191  btVector3 halfExtents = getHalfExtentsWithoutMargin();
192 
193  switch (i)
194  {
195  case 0:
196  plane.setValue(btScalar(1.), btScalar(0.), btScalar(0.), -halfExtents.x());
197  break;
198  case 1:
199  plane.setValue(btScalar(-1.), btScalar(0.), btScalar(0.), -halfExtents.x());
200  break;
201  case 2:
202  plane.setValue(btScalar(0.), btScalar(1.), btScalar(0.), -halfExtents.y());
203  break;
204  case 3:
205  plane.setValue(btScalar(0.), btScalar(-1.), btScalar(0.), -halfExtents.y());
206  break;
207  case 4:
208  plane.setValue(btScalar(0.), btScalar(0.), btScalar(1.), -halfExtents.z());
209  break;
210  case 5:
211  plane.setValue(btScalar(0.), btScalar(0.), btScalar(-1.), -halfExtents.z());
212  break;
213  default:
214  btAssert(0);
215  }
216  }
217 
218  virtual void getEdge(int i, btVector3& pa, btVector3& pb) const
219  //virtual void getEdge(int i,Edge& edge) const
220  {
221  int edgeVert0 = 0;
222  int edgeVert1 = 0;
223 
224  switch (i)
225  {
226  case 0:
227  edgeVert0 = 0;
228  edgeVert1 = 1;
229  break;
230  case 1:
231  edgeVert0 = 0;
232  edgeVert1 = 2;
233  break;
234  case 2:
235  edgeVert0 = 1;
236  edgeVert1 = 3;
237 
238  break;
239  case 3:
240  edgeVert0 = 2;
241  edgeVert1 = 3;
242  break;
243  case 4:
244  edgeVert0 = 0;
245  edgeVert1 = 4;
246  break;
247  case 5:
248  edgeVert0 = 1;
249  edgeVert1 = 5;
250 
251  break;
252  case 6:
253  edgeVert0 = 2;
254  edgeVert1 = 6;
255  break;
256  case 7:
257  edgeVert0 = 3;
258  edgeVert1 = 7;
259  break;
260  case 8:
261  edgeVert0 = 4;
262  edgeVert1 = 5;
263  break;
264  case 9:
265  edgeVert0 = 4;
266  edgeVert1 = 6;
267  break;
268  case 10:
269  edgeVert0 = 5;
270  edgeVert1 = 7;
271  break;
272  case 11:
273  edgeVert0 = 6;
274  edgeVert1 = 7;
275  break;
276  default:
277  btAssert(0);
278  }
279 
280  getVertex(edgeVert0, pa);
281  getVertex(edgeVert1, pb);
282  }
283 
284  virtual bool isInside(const btVector3& pt, btScalar tolerance) const
285  {
286  btVector3 halfExtents = getHalfExtentsWithoutMargin();
287 
288  //btScalar minDist = 2*tolerance;
289 
290  bool result = (pt.x() <= (halfExtents.x() + tolerance)) &&
291  (pt.x() >= (-halfExtents.x() - tolerance)) &&
292  (pt.y() <= (halfExtents.y() + tolerance)) &&
293  (pt.y() >= (-halfExtents.y() - tolerance)) &&
294  (pt.z() <= (halfExtents.z() + tolerance)) &&
295  (pt.z() >= (-halfExtents.z() - tolerance));
296 
297  return result;
298  }
299 
300  //debugging
301  virtual const char* getName() const
302  {
303  return "Box2d";
304  }
305 
307  {
308  return 6;
309  }
310 
311  virtual void getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
312  {
313  switch (index)
314  {
315  case 0:
316  penetrationVector.setValue(btScalar(1.), btScalar(0.), btScalar(0.));
317  break;
318  case 1:
319  penetrationVector.setValue(btScalar(-1.), btScalar(0.), btScalar(0.));
320  break;
321  case 2:
322  penetrationVector.setValue(btScalar(0.), btScalar(1.), btScalar(0.));
323  break;
324  case 3:
325  penetrationVector.setValue(btScalar(0.), btScalar(-1.), btScalar(0.));
326  break;
327  case 4:
328  penetrationVector.setValue(btScalar(0.), btScalar(0.), btScalar(1.));
329  break;
330  case 5:
331  penetrationVector.setValue(btScalar(0.), btScalar(0.), btScalar(-1.));
332  break;
333  default:
334  btAssert(0);
335  }
336  }
337 };
338 
339 #endif //BT_OBB_BOX_2D_SHAPE_H
@ BOX_2D_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 SIMD_FORCE_INLINE
Definition: btScalar.h:98
#define btFsels(a, b, c)
Definition: btScalar.h:603
#define btAssert(x)
Definition: btScalar.h:153
The btBox2dShape is a box primitive around the origin, its sides axis aligned with length specified b...
Definition: btBox2dShape.h:28
const btVector3 * getVertices() const
Definition: btBox2dShape.h:145
virtual int getNumVertices() const
Definition: btBox2dShape.h:140
const btVector3 * getNormals() const
Definition: btBox2dShape.h:150
btVector3 m_centroid
Definition: btBox2dShape.h:31
virtual void getPlane(btVector3 &planeNormal, btVector3 &planeSupport, int i) const
Definition: btBox2dShape.h:155
virtual int getNumEdges() const
Definition: btBox2dShape.h:174
btBox2dShape(const btVector3 &boxHalfExtents)
a btBox2dShape is a flat 2D box in the X-Y plane (Z extents are zero)
Definition: btBox2dShape.h:85
virtual void setLocalScaling(const btVector3 &scaling)
Definition: btBox2dShape.h:120
virtual void setMargin(btScalar collisionMargin)
Definition: btBox2dShape.h:110
virtual int getNumPreferredPenetrationDirections() const
Definition: btBox2dShape.h:306
int getVertexCount() const
Definition: btBox2dShape.h:135
virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3 *vectors, btVector3 *supportVerticesOut, int numVectors) const
Definition: btBox2dShape.h:71
const btVector3 & getCentroid() const
Definition: btBox2dShape.h:164
virtual bool isInside(const btVector3 &pt, btScalar tolerance) const
Definition: btBox2dShape.h:284
btVector3 localGetSupportingVertexWithoutMargin(const btVector3 &vec) const
Definition: btBox2dShape.h:62
const btVector3 & getHalfExtentsWithoutMargin() const
Definition: btBox2dShape.h:46
virtual void getEdge(int i, btVector3 &pa, btVector3 &pb) const
Definition: btBox2dShape.h:218
virtual const char * getName() const
Definition: btBox2dShape.h:301
BT_DECLARE_ALIGNED_ALLOCATOR()
virtual void getPlaneEquation(btVector4 &plane, int i) const
Definition: btBox2dShape.h:189
btVector3 getHalfExtentsWithMargin() const
Definition: btBox2dShape.h:38
virtual int getNumPlanes() const
Definition: btBox2dShape.h:169
virtual void getVertex(int i, btVector3 &vtx) const
Definition: btBox2dShape.h:179
virtual btVector3 localGetSupportingVertex(const btVector3 &vec) const
Definition: btBox2dShape.h:51
virtual void getPreferredPenetrationDirection(int index, btVector3 &penetrationVector) const
Definition: btBox2dShape.h:311
virtual void setMargin(btScalar margin)
virtual void setLocalScaling(const btVector3 &scaling)
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
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:82
const btScalar & y() const
Return the y value.
Definition: btVector3.h:577
const btScalar & z() const
Return the z value.
Definition: btVector3.h:579
const btScalar & getX() const
Return the x value.
Definition: btVector3.h:561
const btScalar & getZ() const
Return the z value.
Definition: btVector3.h:565
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z)
Definition: btVector3.h:640
const btScalar & x() const
Return the x value.
Definition: btVector3.h:575
const btScalar & getY() const
Return the y value.
Definition: btVector3.h:563
void setValue(const btScalar &_x, const btScalar &_y, const btScalar &_z, const btScalar &_w)
Set x,y,z and zero w.
Definition: btVector3.h:1198