Bullet Collision Detection & Physics Library
btSequentialImpulseConstraintSolver.h
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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_SEQUENTIAL_IMPULSE_CONSTRAINT_SOLVER_H
17 #define BT_SEQUENTIAL_IMPULSE_CONSTRAINT_SOLVER_H
18 
19 class btIDebugDraw;
21 class btDispatcher;
22 class btCollisionObject;
29 
31 
35 {
36 protected:
42 
49  // When running solvers on multiple threads, a race condition exists for Kinematic objects that
50  // participate in more than one solver.
51  // The getOrInitSolverBody() function writes the companionId of each body (storing the index of the solver body
52  // for the current solver). For normal dynamic bodies it isn't an issue because they can only be in one island
53  // (and therefore one thread) at a time. But kinematic bodies can be in multiple islands at once.
54  // To avoid this race condition, this solver does not write the companionId, instead it stores the solver body
55  // index in this solver-local table, indexed by the uniqueId of the body.
57 
61  int m_cachedSolverMode; // used to check if SOLVER_SIMD flag has been changed
62  void setupSolverFunctions(bool useSimd);
63 
65 
66  void setupFrictionConstraint(btSolverConstraint & solverConstraint, const btVector3& normalAxis, int solverBodyIdA, int solverBodyIdB,
67  btManifoldPoint& cp, const btVector3& rel_pos1, const btVector3& rel_pos2,
68  btCollisionObject* colObj0, btCollisionObject* colObj1, btScalar relaxation,
69  const btContactSolverInfo& infoGlobal,
70  btScalar desiredVelocity = 0., btScalar cfmSlip = 0.);
71 
72  void setupTorsionalFrictionConstraint(btSolverConstraint & solverConstraint, const btVector3& normalAxis, int solverBodyIdA, int solverBodyIdB,
73  btManifoldPoint& cp, btScalar combinedTorsionalFriction, const btVector3& rel_pos1, const btVector3& rel_pos2,
74  btCollisionObject* colObj0, btCollisionObject* colObj1, btScalar relaxation,
75  btScalar desiredVelocity = 0., btScalar cfmSlip = 0.);
76 
77  btSolverConstraint& addFrictionConstraint(const btVector3& normalAxis, int solverBodyIdA, int solverBodyIdB, int frictionIndex, btManifoldPoint& cp, const btVector3& rel_pos1, const btVector3& rel_pos2, btCollisionObject* colObj0, btCollisionObject* colObj1, btScalar relaxation, const btContactSolverInfo& infoGlobal, btScalar desiredVelocity = 0., btScalar cfmSlip = 0.);
78  btSolverConstraint& addTorsionalFrictionConstraint(const btVector3& normalAxis, int solverBodyIdA, int solverBodyIdB, int frictionIndex, btManifoldPoint& cp, btScalar torsionalFriction, const btVector3& rel_pos1, const btVector3& rel_pos2, btCollisionObject* colObj0, btCollisionObject* colObj1, btScalar relaxation, btScalar desiredVelocity = 0, btScalar cfmSlip = 0.f);
79 
80  void setupContactConstraint(btSolverConstraint & solverConstraint, int solverBodyIdA, int solverBodyIdB, btManifoldPoint& cp,
81  const btContactSolverInfo& infoGlobal, btScalar& relaxation, const btVector3& rel_pos1, const btVector3& rel_pos2);
82 
83  static void applyAnisotropicFriction(btCollisionObject * colObj, btVector3 & frictionDirection, int frictionMode);
84 
85  void setFrictionConstraintImpulse(btSolverConstraint & solverConstraint, int solverBodyIdA, int solverBodyIdB,
86  btManifoldPoint& cp, const btContactSolverInfo& infoGlobal);
87 
89  unsigned long m_btSeed2;
90 
91  btScalar restitutionCurve(btScalar rel_vel, btScalar restitution, btScalar velocityThreshold);
92 
93  virtual void convertContacts(btPersistentManifold * *manifoldPtr, int numManifolds, const btContactSolverInfo& infoGlobal);
94 
95  void convertContact(btPersistentManifold * manifold, const btContactSolverInfo& infoGlobal);
96 
97  virtual void convertJoints(btTypedConstraint * *constraints, int numConstraints, const btContactSolverInfo& infoGlobal);
98  void convertJoint(btSolverConstraint * currentConstraintRow, btTypedConstraint * constraint, const btTypedConstraint::btConstraintInfo1& info1, int solverBodyIdA, int solverBodyIdB, const btContactSolverInfo& infoGlobal);
99 
100  virtual void convertBodies(btCollisionObject * *bodies, int numBodies, const btContactSolverInfo& infoGlobal);
101 
103  {
104  return m_resolveSplitPenetrationImpulse(bodyA, bodyB, contactConstraint);
105  }
106 
108  {
109  return m_resolveSplitPenetrationImpulse(bodyA, bodyB, contactConstraint);
110  }
111 
112  //internal method
113  int getOrInitSolverBody(btCollisionObject & body, btScalar timeStep);
114  void initSolverBody(btSolverBody * solverBody, btCollisionObject * collisionObject, btScalar timeStep);
115 
116  btScalar resolveSingleConstraintRowGeneric(btSolverBody & bodyA, btSolverBody & bodyB, const btSolverConstraint& contactConstraint);
117  btScalar resolveSingleConstraintRowGenericSIMD(btSolverBody & bodyA, btSolverBody & bodyB, const btSolverConstraint& contactConstraint);
118  btScalar resolveSingleConstraintRowLowerLimit(btSolverBody & bodyA, btSolverBody & bodyB, const btSolverConstraint& contactConstraint);
119  btScalar resolveSingleConstraintRowLowerLimitSIMD(btSolverBody & bodyA, btSolverBody & bodyB, const btSolverConstraint& contactConstraint);
121  {
122  return m_resolveSplitPenetrationImpulse(bodyA, bodyB, contactConstraint);
123  }
124 
125 protected:
126  void writeBackContacts(int iBegin, int iEnd, const btContactSolverInfo& infoGlobal);
127  void writeBackJoints(int iBegin, int iEnd, const btContactSolverInfo& infoGlobal);
128  void writeBackBodies(int iBegin, int iEnd, const btContactSolverInfo& infoGlobal);
129  virtual void solveGroupCacheFriendlySplitImpulseIterations(btCollisionObject * *bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer);
130  virtual btScalar solveGroupCacheFriendlyFinish(btCollisionObject * *bodies, int numBodies, const btContactSolverInfo& infoGlobal);
131  virtual btScalar solveSingleIteration(int iteration, btCollisionObject** bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer);
132 
133  virtual btScalar solveGroupCacheFriendlySetup(btCollisionObject * *bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer);
134  virtual btScalar solveGroupCacheFriendlyIterations(btCollisionObject * *bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer);
135 
136 public:
138 
141 
142  virtual btScalar solveGroup(btCollisionObject * *bodies, int numBodies, btPersistentManifold** manifold, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& info, btIDebugDraw* debugDrawer, btDispatcher* dispatcher);
143 
145  virtual void reset();
146 
147  unsigned long btRand2();
148 
149  int btRandInt2(int n);
150 
151  void setRandSeed(unsigned long seed)
152  {
153  m_btSeed2 = seed;
154  }
155  unsigned long getRandSeed() const
156  {
157  return m_btSeed2;
158  }
159 
161  {
163  }
164 
166  {
167  return m_resolveSingleConstraintRowGeneric;
168  }
170  {
171  m_resolveSingleConstraintRowGeneric = rowSolver;
172  }
174  {
175  return m_resolveSingleConstraintRowLowerLimit;
176  }
178  {
179  m_resolveSingleConstraintRowLowerLimit = rowSolver;
180  }
181 
183  btSingleConstraintRowSolver getScalarConstraintRowSolverGeneric();
184  btSingleConstraintRowSolver getSSE2ConstraintRowSolverGeneric();
185  btSingleConstraintRowSolver getSSE4_1ConstraintRowSolverGeneric();
186 
188  btSingleConstraintRowSolver getScalarConstraintRowSolverLowerLimit();
189  btSingleConstraintRowSolver getSSE2ConstraintRowSolverLowerLimit();
190  btSingleConstraintRowSolver getSSE4_1ConstraintRowSolverLowerLimit();
191 };
192 
193 #endif //BT_SEQUENTIAL_IMPULSE_CONSTRAINT_SOLVER_H
btPersistentManifold is a contact point cache, it stays persistent as long as objects are overlapping...
btConstraintSolverType
btConstraintSolver provides solver interface
void setConstraintRowSolverGeneric(btSingleConstraintRowSolver rowSolver)
1D constraint along a normal axis between bodyA and bodyB. It can be combined to solve contact and fr...
btSingleConstraintRowSolver m_resolveSingleConstraintRowGeneric
ManifoldContactPoint collects and maintains persistent contactpoints.
btSingleConstraintRowSolver getActiveConstraintRowSolverLowerLimit()
virtual btConstraintSolverType getSolverType() const
btAlignedObjectArray< btSolverBody > m_tmpSolverBodyPool
btScalar(* btSingleConstraintRowSolver)(btSolverBody &, btSolverBody &, const btSolverConstraint &)
btScalar resolveSplitPenetrationSIMD(btSolverBody &bodyA, btSolverBody &bodyB, const btSolverConstraint &contactConstraint)
btCollisionObject can be used to manage collision detection objects.
The btIDebugDraw interface class allows hooking up a debug renderer to visually debug simulations...
Definition: btIDebugDraw.h:26
The btSequentialImpulseConstraintSolver is a fast SIMD implementation of the Projected Gauss Seidel (...
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:80
#define ATTRIBUTE_ALIGNED16(a)
Definition: btScalar.h:84
btScalar resolveSplitPenetrationImpulse(btSolverBody &bodyA, btSolverBody &bodyB, const btSolverConstraint &contactConstraint)
The btSolverBody is an internal datastructure for the constraint solver. Only necessary data is packe...
Definition: btSolverBody.h:103
btAlignedObjectArray< btTypedConstraint::btConstraintInfo1 > m_tmpConstraintSizesPool
TypedConstraint is the baseclass for Bullet constraints and vehicles.
#define BT_DECLARE_ALIGNED_ALLOCATOR()
Definition: btScalar.h:405
unsigned long m_btSeed2
m_btSeed2 is used for re-arranging the constraint rows. improves convergence/quality of friction ...
btScalar resolveSplitPenetrationImpulseCacheFriendly(btSolverBody &bodyA, btSolverBody &bodyB, const btSolverConstraint &contactConstraint)
The btDispatcher interface class can be used in combination with broadphase to dispatch calculations ...
Definition: btDispatcher.h:76
btSingleConstraintRowSolver getActiveConstraintRowSolverGeneric()
btSingleConstraintRowSolver m_resolveSingleConstraintRowLowerLimit
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:294
void setConstraintRowSolverLowerLimit(btSingleConstraintRowSolver rowSolver)
btAlignedObjectArray< int > m_kinematicBodyUniqueIdToSolverBodyTable