1 files changed, 177 insertions, 0 deletions
diff --git a/thirdparty/bullet/src/BulletDynamics/ConstraintSolver/btContactConstraint.cpp b/thirdparty/bullet/src/BulletDynamics/ConstraintSolver/btContactConstraint.cpp
new file mode 100644
index 0000000000..1098d0c96b
--- /dev/null
+++ b/thirdparty/bullet/src/BulletDynamics/ConstraintSolver/btContactConstraint.cpp
@@ -0,0 +1,177 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+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.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+
+#include "btContactConstraint.h"
+#include "BulletDynamics/Dynamics/btRigidBody.h"
+#include "LinearMath/btVector3.h"
+#include "btJacobianEntry.h"
+#include "btContactSolverInfo.h"
+#include "LinearMath/btMinMax.h"
+#include "BulletCollision/NarrowPhaseCollision/btManifoldPoint.h"
+
+
+
+btContactConstraint::btContactConstraint(btPersistentManifold* contactManifold,btRigidBody& rbA,btRigidBody& rbB)
+:btTypedConstraint(CONTACT_CONSTRAINT_TYPE,rbA,rbB),
+	m_contactManifold(*contactManifold)
+{
+
+}
+
+btContactConstraint::~btContactConstraint()
+{
+
+}
+
+void	btContactConstraint::setContactManifold(btPersistentManifold* contactManifold)
+{
+	m_contactManifold = *contactManifold;
+}
+
+void btContactConstraint::getInfo1 (btConstraintInfo1* info)
+{
+
+}
+
+void btContactConstraint::getInfo2 (btConstraintInfo2* info)
+{
+
+}
+
+void	btContactConstraint::buildJacobian()
+{
+
+}
+
+
+
+
+
+#include "btContactConstraint.h"
+#include "BulletDynamics/Dynamics/btRigidBody.h"
+#include "LinearMath/btVector3.h"
+#include "btJacobianEntry.h"
+#include "btContactSolverInfo.h"
+#include "LinearMath/btMinMax.h"
+#include "BulletCollision/NarrowPhaseCollision/btManifoldPoint.h"
+
+
+
+//response  between two dynamic objects without friction and no restitution, assuming 0 penetration depth
+btScalar resolveSingleCollision(
+        btRigidBody* body1,
+        btCollisionObject* colObj2,
+		const btVector3& contactPositionWorld,
+		const btVector3& contactNormalOnB,
+        const btContactSolverInfo& solverInfo,
+		btScalar distance)
+{
+	btRigidBody* body2 = btRigidBody::upcast(colObj2);
+    
+	
+    const btVector3& normal = contactNormalOnB;
+
+    btVector3 rel_pos1 = contactPositionWorld - body1->getWorldTransform().getOrigin(); 
+    btVector3 rel_pos2 = contactPositionWorld - colObj2->getWorldTransform().getOrigin();
+    
+    btVector3 vel1 = body1->getVelocityInLocalPoint(rel_pos1);
+	btVector3 vel2 = body2? body2->getVelocityInLocalPoint(rel_pos2) : btVector3(0,0,0);
+    btVector3 vel = vel1 - vel2;
+    btScalar rel_vel;
+    rel_vel = normal.dot(vel);
+    
+    btScalar combinedRestitution = 0.f;
+    btScalar restitution = combinedRestitution* -rel_vel;
+
+    btScalar positionalError = solverInfo.m_erp *-distance /solverInfo.m_timeStep ;
+    btScalar velocityError = -(1.0f + restitution) * rel_vel;// * damping;
+	btScalar denom0 = body1->computeImpulseDenominator(contactPositionWorld,normal);
+	btScalar denom1 = body2? body2->computeImpulseDenominator(contactPositionWorld,normal) : 0.f;
+	btScalar relaxation = 1.f;
+	btScalar jacDiagABInv = relaxation/(denom0+denom1);
+
+    btScalar penetrationImpulse = positionalError * jacDiagABInv;
+    btScalar velocityImpulse = velocityError * jacDiagABInv;
+
+    btScalar normalImpulse = penetrationImpulse+velocityImpulse;
+    normalImpulse = 0.f > normalImpulse ? 0.f: normalImpulse;
+
+	body1->applyImpulse(normal*(normalImpulse), rel_pos1);
+    if (body2)
+		body2->applyImpulse(-normal*(normalImpulse), rel_pos2);
+    
+    return normalImpulse;
+}
+
+
+//bilateral constraint between two dynamic objects
+void resolveSingleBilateral(btRigidBody& body1, const btVector3& pos1,
+                      btRigidBody& body2, const btVector3& pos2,
+                      btScalar distance, const btVector3& normal,btScalar& impulse ,btScalar timeStep)
+{
+	(void)timeStep;
+	(void)distance;
+
+
+	btScalar normalLenSqr = normal.length2();
+	btAssert(btFabs(normalLenSqr) < btScalar(1.1));
+	if (normalLenSqr > btScalar(1.1))
+	{
+		impulse = btScalar(0.);
+		return;
+	}
+	btVector3 rel_pos1 = pos1 - body1.getCenterOfMassPosition(); 
+	btVector3 rel_pos2 = pos2 - body2.getCenterOfMassPosition();
+	//this jacobian entry could be re-used for all iterations
+	
+	btVector3 vel1 = body1.getVelocityInLocalPoint(rel_pos1);
+	btVector3 vel2 = body2.getVelocityInLocalPoint(rel_pos2);
+	btVector3 vel = vel1 - vel2;
+	
+
+	   btJacobianEntry jac(body1.getCenterOfMassTransform().getBasis().transpose(),
+		body2.getCenterOfMassTransform().getBasis().transpose(),
+		rel_pos1,rel_pos2,normal,body1.getInvInertiaDiagLocal(),body1.getInvMass(),
+		body2.getInvInertiaDiagLocal(),body2.getInvMass());
+
+	btScalar jacDiagAB = jac.getDiagonal();
+	btScalar jacDiagABInv = btScalar(1.) / jacDiagAB;
+	
+	  btScalar rel_vel = jac.getRelativeVelocity(
+		body1.getLinearVelocity(),
+		body1.getCenterOfMassTransform().getBasis().transpose() * body1.getAngularVelocity(),
+		body2.getLinearVelocity(),
+		body2.getCenterOfMassTransform().getBasis().transpose() * body2.getAngularVelocity()); 
+
+
+
+	rel_vel = normal.dot(vel);
+	
+	//todo: move this into proper structure
+	btScalar contactDamping = btScalar(0.2);
+
+#ifdef ONLY_USE_LINEAR_MASS
+	btScalar massTerm = btScalar(1.) / (body1.getInvMass() + body2.getInvMass());
+	impulse = - contactDamping * rel_vel * massTerm;
+#else	
+	btScalar velocityImpulse = -contactDamping * rel_vel * jacDiagABInv;
+	impulse = velocityImpulse;
+#endif
+}
+
+
+
+