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_BOX_MINKOWSKI_H
17 #define BT_OBB_BOX_MINKOWSKI_H
18
19 #include "btPolyhedralConvexShape.h"
20 #include "btCollisionMargin.h"
21 #include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
22 #include "LinearMath/btVector3.h"
23 #include "LinearMath/btMinMax.h"
24
25 ///The btBoxShape is a box primitive around the origin, its sides axis aligned with length specified by half extents, in local shape coordinates. When used as part of a btCollisionObject or btRigidBody it will be an oriented box in world space.
ATTRIBUTE_ALIGNED16(class)26 ATTRIBUTE_ALIGNED16(class)
27 btBoxShape : public btPolyhedralConvexShape
28 {
29 //btVector3 m_boxHalfExtents1; //use m_implicitShapeDimensions instead
30
31 public:
32 BT_DECLARE_ALIGNED_ALLOCATOR();
33
34 btVector3 getHalfExtentsWithMargin() const
35 {
36 btVector3 halfExtents = getHalfExtentsWithoutMargin();
37 btVector3 margin(getMargin(), getMargin(), getMargin());
38 halfExtents += margin;
39 return halfExtents;
40 }
41
42 const btVector3& getHalfExtentsWithoutMargin() const
43 {
44 return m_implicitShapeDimensions; //scaling is included, margin is not
45 }
46
47 virtual btVector3 localGetSupportingVertex(const btVector3& vec) const
48 {
49 btVector3 halfExtents = getHalfExtentsWithoutMargin();
50 btVector3 margin(getMargin(), getMargin(), getMargin());
51 halfExtents += margin;
52
53 return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
54 btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
55 btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
56 }
57
58 SIMD_FORCE_INLINE btVector3 localGetSupportingVertexWithoutMargin(const btVector3& vec) const
59 {
60 const btVector3& halfExtents = getHalfExtentsWithoutMargin();
61
62 return btVector3(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
63 btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
64 btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
65 }
66
67 virtual void batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors, btVector3* supportVerticesOut, int numVectors) const
68 {
69 const btVector3& halfExtents = getHalfExtentsWithoutMargin();
70
71 for (int i = 0; i < numVectors; i++)
72 {
73 const btVector3& vec = vectors[i];
74 supportVerticesOut[i].setValue(btFsels(vec.x(), halfExtents.x(), -halfExtents.x()),
75 btFsels(vec.y(), halfExtents.y(), -halfExtents.y()),
76 btFsels(vec.z(), halfExtents.z(), -halfExtents.z()));
77 }
78 }
79
80 btBoxShape(const btVector3& boxHalfExtents);
81
82 virtual void setMargin(btScalar collisionMargin)
83 {
84 //correct the m_implicitShapeDimensions for the margin
85 btVector3 oldMargin(getMargin(), getMargin(), getMargin());
86 btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions + oldMargin;
87
88 btConvexInternalShape::setMargin(collisionMargin);
89 btVector3 newMargin(getMargin(), getMargin(), getMargin());
90 m_implicitShapeDimensions = implicitShapeDimensionsWithMargin - newMargin;
91 }
92 virtual void setLocalScaling(const btVector3& scaling)
93 {
94 btVector3 oldMargin(getMargin(), getMargin(), getMargin());
95 btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions + oldMargin;
96 btVector3 unScaledImplicitShapeDimensionsWithMargin = implicitShapeDimensionsWithMargin / m_localScaling;
97
98 btConvexInternalShape::setLocalScaling(scaling);
99
100 m_implicitShapeDimensions = (unScaledImplicitShapeDimensionsWithMargin * m_localScaling) - oldMargin;
101 }
102
103 virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const;
104
105 virtual void calculateLocalInertia(btScalar mass, btVector3 & inertia) const;
106
107 virtual void getPlane(btVector3 & planeNormal, btVector3 & planeSupport, int i) const
108 {
109 //this plane might not be aligned...
110 btVector4 plane;
111 getPlaneEquation(plane, i);
112 planeNormal = btVector3(plane.getX(), plane.getY(), plane.getZ());
113 planeSupport = localGetSupportingVertex(-planeNormal);
114 }
115
116 virtual int getNumPlanes() const
117 {
118 return 6;
119 }
120
121 virtual int getNumVertices() const
122 {
123 return 8;
124 }
125
126 virtual int getNumEdges() const
127 {
128 return 12;
129 }
130
131 virtual void getVertex(int i, btVector3& vtx) const
132 {
133 btVector3 halfExtents = getHalfExtentsWithMargin();
134
135 vtx = btVector3(
136 halfExtents.x() * (1 - (i & 1)) - halfExtents.x() * (i & 1),
137 halfExtents.y() * (1 - ((i & 2) >> 1)) - halfExtents.y() * ((i & 2) >> 1),
138 halfExtents.z() * (1 - ((i & 4) >> 2)) - halfExtents.z() * ((i & 4) >> 2));
139 }
140
141 virtual void getPlaneEquation(btVector4 & plane, int i) const
142 {
143 btVector3 halfExtents = getHalfExtentsWithoutMargin();
144
145 switch (i)
146 {
147 case 0:
148 plane.setValue(btScalar(1.), btScalar(0.), btScalar(0.), -halfExtents.x());
149 break;
150 case 1:
151 plane.setValue(btScalar(-1.), btScalar(0.), btScalar(0.), -halfExtents.x());
152 break;
153 case 2:
154 plane.setValue(btScalar(0.), btScalar(1.), btScalar(0.), -halfExtents.y());
155 break;
156 case 3:
157 plane.setValue(btScalar(0.), btScalar(-1.), btScalar(0.), -halfExtents.y());
158 break;
159 case 4:
160 plane.setValue(btScalar(0.), btScalar(0.), btScalar(1.), -halfExtents.z());
161 break;
162 case 5:
163 plane.setValue(btScalar(0.), btScalar(0.), btScalar(-1.), -halfExtents.z());
164 break;
165 default:
166 btAssert(0);
167 }
168 }
169
170 virtual void getEdge(int i, btVector3& pa, btVector3& pb) const
171 //virtual void getEdge(int i,Edge& edge) const
172 {
173 int edgeVert0 = 0;
174 int edgeVert1 = 0;
175
176 switch (i)
177 {
178 case 0:
179 edgeVert0 = 0;
180 edgeVert1 = 1;
181 break;
182 case 1:
183 edgeVert0 = 0;
184 edgeVert1 = 2;
185 break;
186 case 2:
187 edgeVert0 = 1;
188 edgeVert1 = 3;
189
190 break;
191 case 3:
192 edgeVert0 = 2;
193 edgeVert1 = 3;
194 break;
195 case 4:
196 edgeVert0 = 0;
197 edgeVert1 = 4;
198 break;
199 case 5:
200 edgeVert0 = 1;
201 edgeVert1 = 5;
202
203 break;
204 case 6:
205 edgeVert0 = 2;
206 edgeVert1 = 6;
207 break;
208 case 7:
209 edgeVert0 = 3;
210 edgeVert1 = 7;
211 break;
212 case 8:
213 edgeVert0 = 4;
214 edgeVert1 = 5;
215 break;
216 case 9:
217 edgeVert0 = 4;
218 edgeVert1 = 6;
219 break;
220 case 10:
221 edgeVert0 = 5;
222 edgeVert1 = 7;
223 break;
224 case 11:
225 edgeVert0 = 6;
226 edgeVert1 = 7;
227 break;
228 default:
229 btAssert(0);
230 }
231
232 getVertex(edgeVert0, pa);
233 getVertex(edgeVert1, pb);
234 }
235
236 virtual bool isInside(const btVector3& pt, btScalar tolerance) const
237 {
238 btVector3 halfExtents = getHalfExtentsWithoutMargin();
239
240 //btScalar minDist = 2*tolerance;
241
242 bool result = (pt.x() <= (halfExtents.x() + tolerance)) &&
243 (pt.x() >= (-halfExtents.x() - tolerance)) &&
244 (pt.y() <= (halfExtents.y() + tolerance)) &&
245 (pt.y() >= (-halfExtents.y() - tolerance)) &&
246 (pt.z() <= (halfExtents.z() + tolerance)) &&
247 (pt.z() >= (-halfExtents.z() - tolerance));
248
249 return result;
250 }
251
252 //debugging
253 virtual const char* getName() const
254 {
255 return "Box";
256 }
257
258 virtual int getNumPreferredPenetrationDirections() const
259 {
260 return 6;
261 }
262
263 virtual void getPreferredPenetrationDirection(int index, btVector3& penetrationVector) const
264 {
265 switch (index)
266 {
267 case 0:
268 penetrationVector.setValue(btScalar(1.), btScalar(0.), btScalar(0.));
269 break;
270 case 1:
271 penetrationVector.setValue(btScalar(-1.), btScalar(0.), btScalar(0.));
272 break;
273 case 2:
274 penetrationVector.setValue(btScalar(0.), btScalar(1.), btScalar(0.));
275 break;
276 case 3:
277 penetrationVector.setValue(btScalar(0.), btScalar(-1.), btScalar(0.));
278 break;
279 case 4:
280 penetrationVector.setValue(btScalar(0.), btScalar(0.), btScalar(1.));
281 break;
282 case 5:
283 penetrationVector.setValue(btScalar(0.), btScalar(0.), btScalar(-1.));
284 break;
285 default:
286 btAssert(0);
287 }
288 }
289 };
290
291 #endif //BT_OBB_BOX_MINKOWSKI_H
292