Vendor thirdparty Bullet source for upcoming physics server backend

1 files changed, 186 insertions, 0 deletions

diff --git a/thirdparty/bullet/src/BulletDynamics/Featherstone/btMultiBodyJointMotor.cpp b/thirdparty/bullet/src/BulletDynamics/Featherstone/btMultiBodyJointMotor.cpp
new file mode 100644
index 0000000000..e0921178e9
--- /dev/null
+++ b/thirdparty/bullet/src/BulletDynamics/Featherstone/btMultiBodyJointMotor.cpp
@@ -0,0 +1,186 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2013 Erwin Coumans  http://bulletphysics.org
+
+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.
+*/
+
+///This file was written by Erwin Coumans
+
+#include "btMultiBodyJointMotor.h"
+#include "btMultiBody.h"
+#include "btMultiBodyLinkCollider.h"
+#include "BulletCollision/CollisionDispatch/btCollisionObject.h"
+
+
+btMultiBodyJointMotor::btMultiBodyJointMotor(btMultiBody* body, int link, btScalar desiredVelocity, btScalar maxMotorImpulse)
+	:btMultiBodyConstraint(body,body,link,body->getLink(link).m_parent,1,true),
+	m_desiredVelocity(desiredVelocity),
+	m_desiredPosition(0),
+	m_kd(1.),
+	m_kp(0),
+	m_erp(1),
+	m_rhsClamp(SIMD_INFINITY)
+{
+
+	m_maxAppliedImpulse = maxMotorImpulse;
+	// the data.m_jacobians never change, so may as well
+    // initialize them here
+
+
+}
+
+void btMultiBodyJointMotor::finalizeMultiDof()
+{
+	allocateJacobiansMultiDof();
+	// note: we rely on the fact that data.m_jacobians are
+	// always initialized to zero by the Constraint ctor
+	int linkDoF = 0;
+	unsigned int offset = 6 + (m_bodyA->getLink(m_linkA).m_dofOffset + linkDoF);
+
+	// row 0: the lower bound
+	// row 0: the lower bound
+	jacobianA(0)[offset] = 1;
+
+	m_numDofsFinalized = m_jacSizeBoth;
+}
+
+btMultiBodyJointMotor::btMultiBodyJointMotor(btMultiBody* body, int link, int linkDoF, btScalar desiredVelocity, btScalar maxMotorImpulse)
+	//:btMultiBodyConstraint(body,0,link,-1,1,true),
+	:btMultiBodyConstraint(body,body,link,body->getLink(link).m_parent,1,true),
+	m_desiredVelocity(desiredVelocity),
+	m_desiredPosition(0),
+	m_kd(1.),
+	m_kp(0),
+    m_erp(1),
+	m_rhsClamp(SIMD_INFINITY)
+{
+	btAssert(linkDoF < body->getLink(link).m_dofCount);
+
+	m_maxAppliedImpulse = maxMotorImpulse;
+
+}
+btMultiBodyJointMotor::~btMultiBodyJointMotor()
+{
+}
+
+int btMultiBodyJointMotor::getIslandIdA() const
+{
+	btMultiBodyLinkCollider* col = m_bodyA->getBaseCollider();
+	if (col)
+		return col->getIslandTag();
+	for (int i=0;i<m_bodyA->getNumLinks();i++)
+	{
+		if (m_bodyA->getLink(i).m_collider)
+			return m_bodyA->getLink(i).m_collider->getIslandTag();
+	}
+	return -1;
+}
+
+int btMultiBodyJointMotor::getIslandIdB() const
+{
+	btMultiBodyLinkCollider* col = m_bodyB->getBaseCollider();
+	if (col)
+		return col->getIslandTag();
+
+	for (int i=0;i<m_bodyB->getNumLinks();i++)
+	{
+		col = m_bodyB->getLink(i).m_collider;
+		if (col)
+			return col->getIslandTag();
+	}
+	return -1;
+}
+
+
+void btMultiBodyJointMotor::createConstraintRows(btMultiBodyConstraintArray& constraintRows,
+		btMultiBodyJacobianData& data,
+		const btContactSolverInfo& infoGlobal)
+{
+    // only positions need to be updated -- data.m_jacobians and force
+    // directions were set in the ctor and never change.
+	
+	if (m_numDofsFinalized != m_jacSizeBoth)
+	{
+        finalizeMultiDof();
+	}
+
+	//don't crash
+	if (m_numDofsFinalized != m_jacSizeBoth)
+		return;
+
+	if (m_maxAppliedImpulse==0.f)
+		return;
+
+	const btScalar posError = 0;
+	const btVector3 dummy(0, 0, 0);
+
+	for (int row=0;row<getNumRows();row++)
+	{
+		btMultiBodySolverConstraint& constraintRow = constraintRows.expandNonInitializing();
+
+        int dof = 0;
+        btScalar currentPosition = m_bodyA->getJointPosMultiDof(m_linkA)[dof];
+        btScalar currentVelocity = m_bodyA->getJointVelMultiDof(m_linkA)[dof];
+        btScalar positionStabiliationTerm = m_erp*(m_desiredPosition-currentPosition)/infoGlobal.m_timeStep;
+		
+        btScalar velocityError = (m_desiredVelocity - currentVelocity);
+        btScalar rhs =   m_kp * positionStabiliationTerm + currentVelocity+m_kd * velocityError;
+		if (rhs>m_rhsClamp)
+		{
+			rhs=m_rhsClamp;
+		}
+		if (rhs<-m_rhsClamp)
+		{
+			rhs=-m_rhsClamp;
+		}
+        
+        
+		fillMultiBodyConstraint(constraintRow,data,jacobianA(row),jacobianB(row),dummy,dummy,dummy,dummy,posError,infoGlobal,-m_maxAppliedImpulse,m_maxAppliedImpulse,false,1,false,rhs);
+		constraintRow.m_orgConstraint = this;
+		constraintRow.m_orgDofIndex = row;
+		{
+			//expect either prismatic or revolute joint type for now
+			btAssert((m_bodyA->getLink(m_linkA).m_jointType == btMultibodyLink::eRevolute)||(m_bodyA->getLink(m_linkA).m_jointType == btMultibodyLink::ePrismatic));
+			switch (m_bodyA->getLink(m_linkA).m_jointType)
+			{
+				case btMultibodyLink::eRevolute:
+				{
+					constraintRow.m_contactNormal1.setZero();
+					constraintRow.m_contactNormal2.setZero();
+					btVector3 revoluteAxisInWorld = quatRotate(m_bodyA->getLink(m_linkA).m_cachedWorldTransform.getRotation(),m_bodyA->getLink(m_linkA).m_axes[0].m_topVec);
+					constraintRow.m_relpos1CrossNormal=revoluteAxisInWorld;
+					constraintRow.m_relpos2CrossNormal=-revoluteAxisInWorld;
+					
+					break;
+				}
+				case btMultibodyLink::ePrismatic:
+				{
+					btVector3 prismaticAxisInWorld = quatRotate(m_bodyA->getLink(m_linkA).m_cachedWorldTransform.getRotation(),m_bodyA->getLink(m_linkA).m_axes[0].m_bottomVec);
+					constraintRow.m_contactNormal1=prismaticAxisInWorld;
+					constraintRow.m_contactNormal2=-prismaticAxisInWorld;
+					constraintRow.m_relpos1CrossNormal.setZero();
+					constraintRow.m_relpos2CrossNormal.setZero();
+					
+					break;
+				}
+				default:
+				{
+					btAssert(0);
+				}
+			};
+			
+		}
+
+	}
+
+}
+