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
ATTRIBUTE_ALIGNED16(class)22 ATTRIBUTE_ALIGNED16(class) btTriangleShape : public btPolyhedralConvexShape
23 {
24
25
26 public:
27
28 BT_DECLARE_ALIGNED_ALLOCATOR();
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
69 btVector3 localGetSupportingVertexWithoutMargin(const btVector3& dir)const
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
168 virtual int getNumPreferredPenetrationDirections() const
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
185