2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
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:
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.
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18 #ifndef BT_VORONOI_SIMPLEX_SOLVER_H
19 #define BT_VORONOI_SIMPLEX_SOLVER_H
21 #include "btSimplexSolverInterface.h"
25 #define VORONOI_SIMPLEX_MAX_VERTS 5
27 ///disable next define, or use defaultCollisionConfiguration->getSimplexSolver()->setEqualVertexThreshold(0.f) to disable/configure
28 #define BT_USE_EQUAL_VERTEX_THRESHOLD
29 #define VORONOI_DEFAULT_EQUAL_VERTEX_THRESHOLD 0.0001f
32 struct btUsageBitfield{
45 unsigned short usedVertexA : 1;
46 unsigned short usedVertexB : 1;
47 unsigned short usedVertexC : 1;
48 unsigned short usedVertexD : 1;
49 unsigned short unused1 : 1;
50 unsigned short unused2 : 1;
51 unsigned short unused3 : 1;
52 unsigned short unused4 : 1;
56 struct btSubSimplexClosestResult
58 btVector3 m_closestPointOnSimplex;
59 //MASK for m_usedVertices
60 //stores the simplex vertex-usage, using the MASK,
61 // if m_usedVertices & MASK then the related vertex is used
62 btUsageBitfield m_usedVertices;
63 btScalar m_barycentricCoords[4];
69 setBarycentricCoordinates();
70 m_usedVertices.reset();
74 bool valid = (m_barycentricCoords[0] >= btScalar(0.)) &&
75 (m_barycentricCoords[1] >= btScalar(0.)) &&
76 (m_barycentricCoords[2] >= btScalar(0.)) &&
77 (m_barycentricCoords[3] >= btScalar(0.));
82 void setBarycentricCoordinates(btScalar a=btScalar(0.),btScalar b=btScalar(0.),btScalar c=btScalar(0.),btScalar d=btScalar(0.))
84 m_barycentricCoords[0] = a;
85 m_barycentricCoords[1] = b;
86 m_barycentricCoords[2] = c;
87 m_barycentricCoords[3] = d;
92 /// btVoronoiSimplexSolver is an implementation of the closest point distance algorithm from a 1-4 points simplex to the origin.
93 /// Can be used with GJK, as an alternative to Johnson distance algorithm.
94 #ifdef NO_VIRTUAL_INTERFACE
95 ATTRIBUTE_ALIGNED16(class) btVoronoiSimplexSolver
97 ATTRIBUTE_ALIGNED16(class) btVoronoiSimplexSolver : public btSimplexSolverInterface
102 BT_DECLARE_ALIGNED_ALLOCATOR();
106 btVector3 m_simplexVectorW[VORONOI_SIMPLEX_MAX_VERTS];
107 btVector3 m_simplexPointsP[VORONOI_SIMPLEX_MAX_VERTS];
108 btVector3 m_simplexPointsQ[VORONOI_SIMPLEX_MAX_VERTS];
112 btVector3 m_cachedP1;
113 btVector3 m_cachedP2;
117 btScalar m_equalVertexThreshold;
118 bool m_cachedValidClosest;
121 btSubSimplexClosestResult m_cachedBC;
125 void removeVertex(int index);
126 void reduceVertices (const btUsageBitfield& usedVerts);
127 bool updateClosestVectorAndPoints();
129 bool closestPtPointTetrahedron(const btVector3& p, const btVector3& a, const btVector3& b, const btVector3& c, const btVector3& d, btSubSimplexClosestResult& finalResult);
130 int pointOutsideOfPlane(const btVector3& p, const btVector3& a, const btVector3& b, const btVector3& c, const btVector3& d);
131 bool closestPtPointTriangle(const btVector3& p, const btVector3& a, const btVector3& b, const btVector3& c,btSubSimplexClosestResult& result);
135 btVoronoiSimplexSolver()
136 : m_equalVertexThreshold(VORONOI_DEFAULT_EQUAL_VERTEX_THRESHOLD)
141 void addVertex(const btVector3& w, const btVector3& p, const btVector3& q);
143 void setEqualVertexThreshold(btScalar threshold)
145 m_equalVertexThreshold = threshold;
148 btScalar getEqualVertexThreshold() const
150 return m_equalVertexThreshold;
153 bool closest(btVector3& v);
155 btScalar maxVertex();
157 bool fullSimplex() const
159 return (m_numVertices == 4);
162 int getSimplex(btVector3 *pBuf, btVector3 *qBuf, btVector3 *yBuf) const;
164 bool inSimplex(const btVector3& w);
166 void backup_closest(btVector3& v) ;
168 bool emptySimplex() const ;
170 void compute_points(btVector3& p1, btVector3& p2) ;
172 int numVertices() const
174 return m_numVertices;
180 #endif //BT_VORONOI_SIMPLEX_SOLVER_H