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Diffstat (limited to 'extern/bullet2/BulletDynamics/ConstraintSolver/btGeneric6DofConstraint.cpp')
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diff --git a/extern/bullet2/BulletDynamics/ConstraintSolver/btGeneric6DofConstraint.cpp b/extern/bullet2/BulletDynamics/ConstraintSolver/btGeneric6DofConstraint.cpp new file mode 100644 index 00000000000..a970d706284 --- /dev/null +++ b/extern/bullet2/BulletDynamics/ConstraintSolver/btGeneric6DofConstraint.cpp @@ -0,0 +1,1012 @@ +/* +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. +*/ +/* +2007-09-09 +Refactored by Francisco Le?n +email: projectileman@yahoo.com +http://gimpact.sf.net +*/ + +#include "btGeneric6DofConstraint.h" +#include "BulletDynamics/Dynamics/btRigidBody.h" +#include "LinearMath/btTransformUtil.h" +#include "LinearMath/btTransformUtil.h" +#include <new> + + + +#define D6_USE_OBSOLETE_METHOD false +#define D6_USE_FRAME_OFFSET true + + + + + + +btGeneric6DofConstraint::btGeneric6DofConstraint(btRigidBody& rbA, btRigidBody& rbB, const btTransform& frameInA, const btTransform& frameInB, bool useLinearReferenceFrameA) +: btTypedConstraint(D6_CONSTRAINT_TYPE, rbA, rbB) +, m_frameInA(frameInA) +, m_frameInB(frameInB), +m_useLinearReferenceFrameA(useLinearReferenceFrameA), +m_useOffsetForConstraintFrame(D6_USE_FRAME_OFFSET), +m_flags(0), +m_useSolveConstraintObsolete(D6_USE_OBSOLETE_METHOD) +{ + calculateTransforms(); +} + + + +btGeneric6DofConstraint::btGeneric6DofConstraint(btRigidBody& rbB, const btTransform& frameInB, bool useLinearReferenceFrameB) + : btTypedConstraint(D6_CONSTRAINT_TYPE, getFixedBody(), rbB), + m_frameInB(frameInB), + m_useLinearReferenceFrameA(useLinearReferenceFrameB), + m_useOffsetForConstraintFrame(D6_USE_FRAME_OFFSET), + m_flags(0), + m_useSolveConstraintObsolete(false) +{ + ///not providing rigidbody A means implicitly using worldspace for body A + m_frameInA = rbB.getCenterOfMassTransform() * m_frameInB; + calculateTransforms(); +} + + + + +#define GENERIC_D6_DISABLE_WARMSTARTING 1 + + + +btScalar btGetMatrixElem(const btMatrix3x3& mat, int index); +btScalar btGetMatrixElem(const btMatrix3x3& mat, int index) +{ + int i = index%3; + int j = index/3; + return mat[i][j]; +} + + + +///MatrixToEulerXYZ from http://www.geometrictools.com/LibFoundation/Mathematics/Wm4Matrix3.inl.html +bool matrixToEulerXYZ(const btMatrix3x3& mat,btVector3& xyz); +bool matrixToEulerXYZ(const btMatrix3x3& mat,btVector3& xyz) +{ + // // rot = cy*cz -cy*sz sy + // // cz*sx*sy+cx*sz cx*cz-sx*sy*sz -cy*sx + // // -cx*cz*sy+sx*sz cz*sx+cx*sy*sz cx*cy + // + + btScalar fi = btGetMatrixElem(mat,2); + if (fi < btScalar(1.0f)) + { + if (fi > btScalar(-1.0f)) + { + xyz[0] = btAtan2(-btGetMatrixElem(mat,5),btGetMatrixElem(mat,8)); + xyz[1] = btAsin(btGetMatrixElem(mat,2)); + xyz[2] = btAtan2(-btGetMatrixElem(mat,1),btGetMatrixElem(mat,0)); + return true; + } + else + { + // WARNING. Not unique. XA - ZA = -atan2(r10,r11) + xyz[0] = -btAtan2(btGetMatrixElem(mat,3),btGetMatrixElem(mat,4)); + xyz[1] = -SIMD_HALF_PI; + xyz[2] = btScalar(0.0); + return false; + } + } + else + { + // WARNING. Not unique. XAngle + ZAngle = atan2(r10,r11) + xyz[0] = btAtan2(btGetMatrixElem(mat,3),btGetMatrixElem(mat,4)); + xyz[1] = SIMD_HALF_PI; + xyz[2] = 0.0; + } + return false; +} + +//////////////////////////// btRotationalLimitMotor //////////////////////////////////// + +int btRotationalLimitMotor::testLimitValue(btScalar test_value) +{ + if(m_loLimit>m_hiLimit) + { + m_currentLimit = 0;//Free from violation + return 0; + } + if (test_value < m_loLimit) + { + m_currentLimit = 1;//low limit violation + m_currentLimitError = test_value - m_loLimit; + return 1; + } + else if (test_value> m_hiLimit) + { + m_currentLimit = 2;//High limit violation + m_currentLimitError = test_value - m_hiLimit; + return 2; + }; + + m_currentLimit = 0;//Free from violation + return 0; + +} + + + +btScalar btRotationalLimitMotor::solveAngularLimits( + btScalar timeStep,btVector3& axis,btScalar jacDiagABInv, + btRigidBody * body0, btRigidBody * body1 ) +{ + if (needApplyTorques()==false) return 0.0f; + + btScalar target_velocity = m_targetVelocity; + btScalar maxMotorForce = m_maxMotorForce; + + //current error correction + if (m_currentLimit!=0) + { + target_velocity = -m_stopERP*m_currentLimitError/(timeStep); + maxMotorForce = m_maxLimitForce; + } + + maxMotorForce *= timeStep; + + // current velocity difference + + btVector3 angVelA; + body0->internalGetAngularVelocity(angVelA); + btVector3 angVelB; + body1->internalGetAngularVelocity(angVelB); + + btVector3 vel_diff; + vel_diff = angVelA-angVelB; + + + + btScalar rel_vel = axis.dot(vel_diff); + + // correction velocity + btScalar motor_relvel = m_limitSoftness*(target_velocity - m_damping*rel_vel); + + + if ( motor_relvel < SIMD_EPSILON && motor_relvel > -SIMD_EPSILON ) + { + return 0.0f;//no need for applying force + } + + + // correction impulse + btScalar unclippedMotorImpulse = (1+m_bounce)*motor_relvel*jacDiagABInv; + + // clip correction impulse + btScalar clippedMotorImpulse; + + ///@todo: should clip against accumulated impulse + if (unclippedMotorImpulse>0.0f) + { + clippedMotorImpulse = unclippedMotorImpulse > maxMotorForce? maxMotorForce: unclippedMotorImpulse; + } + else + { + clippedMotorImpulse = unclippedMotorImpulse < -maxMotorForce ? -maxMotorForce: unclippedMotorImpulse; + } + + + // sort with accumulated impulses + btScalar lo = btScalar(-BT_LARGE_FLOAT); + btScalar hi = btScalar(BT_LARGE_FLOAT); + + btScalar oldaccumImpulse = m_accumulatedImpulse; + btScalar sum = oldaccumImpulse + clippedMotorImpulse; + m_accumulatedImpulse = sum > hi ? btScalar(0.) : sum < lo ? btScalar(0.) : sum; + + clippedMotorImpulse = m_accumulatedImpulse - oldaccumImpulse; + + btVector3 motorImp = clippedMotorImpulse * axis; + + //body0->applyTorqueImpulse(motorImp); + //body1->applyTorqueImpulse(-motorImp); + + body0->internalApplyImpulse(btVector3(0,0,0), body0->getInvInertiaTensorWorld()*axis,clippedMotorImpulse); + body1->internalApplyImpulse(btVector3(0,0,0), body1->getInvInertiaTensorWorld()*axis,-clippedMotorImpulse); + + + return clippedMotorImpulse; + + +} + +//////////////////////////// End btRotationalLimitMotor //////////////////////////////////// + + + + +//////////////////////////// btTranslationalLimitMotor //////////////////////////////////// + + +int btTranslationalLimitMotor::testLimitValue(int limitIndex, btScalar test_value) +{ + btScalar loLimit = m_lowerLimit[limitIndex]; + btScalar hiLimit = m_upperLimit[limitIndex]; + if(loLimit > hiLimit) + { + m_currentLimit[limitIndex] = 0;//Free from violation + m_currentLimitError[limitIndex] = btScalar(0.f); + return 0; + } + + if (test_value < loLimit) + { + m_currentLimit[limitIndex] = 2;//low limit violation + m_currentLimitError[limitIndex] = test_value - loLimit; + return 2; + } + else if (test_value> hiLimit) + { + m_currentLimit[limitIndex] = 1;//High limit violation + m_currentLimitError[limitIndex] = test_value - hiLimit; + return 1; + }; + + m_currentLimit[limitIndex] = 0;//Free from violation + m_currentLimitError[limitIndex] = btScalar(0.f); + return 0; +} + + + +btScalar btTranslationalLimitMotor::solveLinearAxis( + btScalar timeStep, + btScalar jacDiagABInv, + btRigidBody& body1,const btVector3 &pointInA, + btRigidBody& body2,const btVector3 &pointInB, + int limit_index, + const btVector3 & axis_normal_on_a, + const btVector3 & anchorPos) +{ + + ///find relative velocity + // btVector3 rel_pos1 = pointInA - body1.getCenterOfMassPosition(); + // btVector3 rel_pos2 = pointInB - body2.getCenterOfMassPosition(); + btVector3 rel_pos1 = anchorPos - body1.getCenterOfMassPosition(); + btVector3 rel_pos2 = anchorPos - body2.getCenterOfMassPosition(); + + btVector3 vel1; + body1.internalGetVelocityInLocalPointObsolete(rel_pos1,vel1); + btVector3 vel2; + body2.internalGetVelocityInLocalPointObsolete(rel_pos2,vel2); + btVector3 vel = vel1 - vel2; + + btScalar rel_vel = axis_normal_on_a.dot(vel); + + + + /// apply displacement correction + + //positional error (zeroth order error) + btScalar depth = -(pointInA - pointInB).dot(axis_normal_on_a); + btScalar lo = btScalar(-BT_LARGE_FLOAT); + btScalar hi = btScalar(BT_LARGE_FLOAT); + + btScalar minLimit = m_lowerLimit[limit_index]; + btScalar maxLimit = m_upperLimit[limit_index]; + + //handle the limits + if (minLimit < maxLimit) + { + { + if (depth > maxLimit) + { + depth -= maxLimit; + lo = btScalar(0.); + + } + else + { + if (depth < minLimit) + { + depth -= minLimit; + hi = btScalar(0.); + } + else + { + return 0.0f; + } + } + } + } + + btScalar normalImpulse= m_limitSoftness*(m_restitution*depth/timeStep - m_damping*rel_vel) * jacDiagABInv; + + + + + btScalar oldNormalImpulse = m_accumulatedImpulse[limit_index]; + btScalar sum = oldNormalImpulse + normalImpulse; + m_accumulatedImpulse[limit_index] = sum > hi ? btScalar(0.) : sum < lo ? btScalar(0.) : sum; + normalImpulse = m_accumulatedImpulse[limit_index] - oldNormalImpulse; + + btVector3 impulse_vector = axis_normal_on_a * normalImpulse; + //body1.applyImpulse( impulse_vector, rel_pos1); + //body2.applyImpulse(-impulse_vector, rel_pos2); + + btVector3 ftorqueAxis1 = rel_pos1.cross(axis_normal_on_a); + btVector3 ftorqueAxis2 = rel_pos2.cross(axis_normal_on_a); + body1.internalApplyImpulse(axis_normal_on_a*body1.getInvMass(), body1.getInvInertiaTensorWorld()*ftorqueAxis1,normalImpulse); + body2.internalApplyImpulse(axis_normal_on_a*body2.getInvMass(), body2.getInvInertiaTensorWorld()*ftorqueAxis2,-normalImpulse); + + + + + return normalImpulse; +} + +//////////////////////////// btTranslationalLimitMotor //////////////////////////////////// + +void btGeneric6DofConstraint::calculateAngleInfo() +{ + btMatrix3x3 relative_frame = m_calculatedTransformA.getBasis().inverse()*m_calculatedTransformB.getBasis(); + matrixToEulerXYZ(relative_frame,m_calculatedAxisAngleDiff); + // in euler angle mode we do not actually constrain the angular velocity + // along the axes axis[0] and axis[2] (although we do use axis[1]) : + // + // to get constrain w2-w1 along ...not + // ------ --------------------- ------ + // d(angle[0])/dt = 0 ax[1] x ax[2] ax[0] + // d(angle[1])/dt = 0 ax[1] + // d(angle[2])/dt = 0 ax[0] x ax[1] ax[2] + // + // constraining w2-w1 along an axis 'a' means that a'*(w2-w1)=0. + // to prove the result for angle[0], write the expression for angle[0] from + // GetInfo1 then take the derivative. to prove this for angle[2] it is + // easier to take the euler rate expression for d(angle[2])/dt with respect + // to the components of w and set that to 0. + btVector3 axis0 = m_calculatedTransformB.getBasis().getColumn(0); + btVector3 axis2 = m_calculatedTransformA.getBasis().getColumn(2); + + m_calculatedAxis[1] = axis2.cross(axis0); + m_calculatedAxis[0] = m_calculatedAxis[1].cross(axis2); + m_calculatedAxis[2] = axis0.cross(m_calculatedAxis[1]); + + m_calculatedAxis[0].normalize(); + m_calculatedAxis[1].normalize(); + m_calculatedAxis[2].normalize(); + +} + +void btGeneric6DofConstraint::calculateTransforms() +{ + calculateTransforms(m_rbA.getCenterOfMassTransform(),m_rbB.getCenterOfMassTransform()); +} + +void btGeneric6DofConstraint::calculateTransforms(const btTransform& transA,const btTransform& transB) +{ + m_calculatedTransformA = transA * m_frameInA; + m_calculatedTransformB = transB * m_frameInB; + calculateLinearInfo(); + calculateAngleInfo(); + if(m_useOffsetForConstraintFrame) + { // get weight factors depending on masses + btScalar miA = getRigidBodyA().getInvMass(); + btScalar miB = getRigidBodyB().getInvMass(); + m_hasStaticBody = (miA < SIMD_EPSILON) || (miB < SIMD_EPSILON); + btScalar miS = miA + miB; + if(miS > btScalar(0.f)) + { + m_factA = miB / miS; + } + else + { + m_factA = btScalar(0.5f); + } + m_factB = btScalar(1.0f) - m_factA; + } +} + + + +void btGeneric6DofConstraint::buildLinearJacobian( + btJacobianEntry & jacLinear,const btVector3 & normalWorld, + const btVector3 & pivotAInW,const btVector3 & pivotBInW) +{ + new (&jacLinear) btJacobianEntry( + m_rbA.getCenterOfMassTransform().getBasis().transpose(), + m_rbB.getCenterOfMassTransform().getBasis().transpose(), + pivotAInW - m_rbA.getCenterOfMassPosition(), + pivotBInW - m_rbB.getCenterOfMassPosition(), + normalWorld, + m_rbA.getInvInertiaDiagLocal(), + m_rbA.getInvMass(), + m_rbB.getInvInertiaDiagLocal(), + m_rbB.getInvMass()); +} + + + +void btGeneric6DofConstraint::buildAngularJacobian( + btJacobianEntry & jacAngular,const btVector3 & jointAxisW) +{ + new (&jacAngular) btJacobianEntry(jointAxisW, + m_rbA.getCenterOfMassTransform().getBasis().transpose(), + m_rbB.getCenterOfMassTransform().getBasis().transpose(), + m_rbA.getInvInertiaDiagLocal(), + m_rbB.getInvInertiaDiagLocal()); + +} + + + +bool btGeneric6DofConstraint::testAngularLimitMotor(int axis_index) +{ + btScalar angle = m_calculatedAxisAngleDiff[axis_index]; + angle = btAdjustAngleToLimits(angle, m_angularLimits[axis_index].m_loLimit, m_angularLimits[axis_index].m_hiLimit); + m_angularLimits[axis_index].m_currentPosition = angle; + //test limits + m_angularLimits[axis_index].testLimitValue(angle); + return m_angularLimits[axis_index].needApplyTorques(); +} + + + +void btGeneric6DofConstraint::buildJacobian() +{ +#ifndef __SPU__ + if (m_useSolveConstraintObsolete) + { + + // Clear accumulated impulses for the next simulation step + m_linearLimits.m_accumulatedImpulse.setValue(btScalar(0.), btScalar(0.), btScalar(0.)); + int i; + for(i = 0; i < 3; i++) + { + m_angularLimits[i].m_accumulatedImpulse = btScalar(0.); + } + //calculates transform + calculateTransforms(m_rbA.getCenterOfMassTransform(),m_rbB.getCenterOfMassTransform()); + + // const btVector3& pivotAInW = m_calculatedTransformA.getOrigin(); + // const btVector3& pivotBInW = m_calculatedTransformB.getOrigin(); + calcAnchorPos(); + btVector3 pivotAInW = m_AnchorPos; + btVector3 pivotBInW = m_AnchorPos; + + // not used here + // btVector3 rel_pos1 = pivotAInW - m_rbA.getCenterOfMassPosition(); + // btVector3 rel_pos2 = pivotBInW - m_rbB.getCenterOfMassPosition(); + + btVector3 normalWorld; + //linear part + for (i=0;i<3;i++) + { + if (m_linearLimits.isLimited(i)) + { + if (m_useLinearReferenceFrameA) + normalWorld = m_calculatedTransformA.getBasis().getColumn(i); + else + normalWorld = m_calculatedTransformB.getBasis().getColumn(i); + + buildLinearJacobian( + m_jacLinear[i],normalWorld , + pivotAInW,pivotBInW); + + } + } + + // angular part + for (i=0;i<3;i++) + { + //calculates error angle + if (testAngularLimitMotor(i)) + { + normalWorld = this->getAxis(i); + // Create angular atom + buildAngularJacobian(m_jacAng[i],normalWorld); + } + } + + } +#endif //__SPU__ + +} + + +void btGeneric6DofConstraint::getInfo1 (btConstraintInfo1* info) +{ + if (m_useSolveConstraintObsolete) + { + info->m_numConstraintRows = 0; + info->nub = 0; + } else + { + //prepare constraint + calculateTransforms(m_rbA.getCenterOfMassTransform(),m_rbB.getCenterOfMassTransform()); + info->m_numConstraintRows = 0; + info->nub = 6; + int i; + //test linear limits + for(i = 0; i < 3; i++) + { + if(m_linearLimits.needApplyForce(i)) + { + info->m_numConstraintRows++; + info->nub--; + } + } + //test angular limits + for (i=0;i<3 ;i++ ) + { + if(testAngularLimitMotor(i)) + { + info->m_numConstraintRows++; + info->nub--; + } + } + } +} + +void btGeneric6DofConstraint::getInfo1NonVirtual (btConstraintInfo1* info) +{ + if (m_useSolveConstraintObsolete) + { + info->m_numConstraintRows = 0; + info->nub = 0; + } else + { + //pre-allocate all 6 + info->m_numConstraintRows = 6; + info->nub = 0; + } +} + + +void btGeneric6DofConstraint::getInfo2 (btConstraintInfo2* info) +{ + getInfo2NonVirtual(info,m_rbA.getCenterOfMassTransform(),m_rbB.getCenterOfMassTransform(), m_rbA.getLinearVelocity(),m_rbB.getLinearVelocity(),m_rbA.getAngularVelocity(), m_rbB.getAngularVelocity()); +} + +void btGeneric6DofConstraint::getInfo2NonVirtual (btConstraintInfo2* info, const btTransform& transA,const btTransform& transB,const btVector3& linVelA,const btVector3& linVelB,const btVector3& angVelA,const btVector3& angVelB) +{ + btAssert(!m_useSolveConstraintObsolete); + //prepare constraint + calculateTransforms(transA,transB); + if(m_useOffsetForConstraintFrame) + { // for stability better to solve angular limits first + int row = setAngularLimits(info, 0,transA,transB,linVelA,linVelB,angVelA,angVelB); + setLinearLimits(info, row, transA,transB,linVelA,linVelB,angVelA,angVelB); + } + else + { // leave old version for compatibility + int row = setLinearLimits(info, 0, transA,transB,linVelA,linVelB,angVelA,angVelB); + setAngularLimits(info, row,transA,transB,linVelA,linVelB,angVelA,angVelB); + } +} + + + +int btGeneric6DofConstraint::setLinearLimits(btConstraintInfo2* info, int row, const btTransform& transA,const btTransform& transB,const btVector3& linVelA,const btVector3& linVelB,const btVector3& angVelA,const btVector3& angVelB) +{ +// int row = 0; + //solve linear limits + btRotationalLimitMotor limot; + for (int i=0;i<3 ;i++ ) + { + if(m_linearLimits.needApplyForce(i)) + { // re-use rotational motor code + limot.m_bounce = btScalar(0.f); + limot.m_currentLimit = m_linearLimits.m_currentLimit[i]; + limot.m_currentPosition = m_linearLimits.m_currentLinearDiff[i]; + limot.m_currentLimitError = m_linearLimits.m_currentLimitError[i]; + limot.m_damping = m_linearLimits.m_damping; + limot.m_enableMotor = m_linearLimits.m_enableMotor[i]; + limot.m_hiLimit = m_linearLimits.m_upperLimit[i]; + limot.m_limitSoftness = m_linearLimits.m_limitSoftness; + limot.m_loLimit = m_linearLimits.m_lowerLimit[i]; + limot.m_maxLimitForce = btScalar(0.f); + limot.m_maxMotorForce = m_linearLimits.m_maxMotorForce[i]; + limot.m_targetVelocity = m_linearLimits.m_targetVelocity[i]; + btVector3 axis = m_calculatedTransformA.getBasis().getColumn(i); + int flags = m_flags >> (i * BT_6DOF_FLAGS_AXIS_SHIFT); + limot.m_normalCFM = (flags & BT_6DOF_FLAGS_CFM_NORM) ? m_linearLimits.m_normalCFM[i] : info->cfm[0]; + limot.m_stopCFM = (flags & BT_6DOF_FLAGS_CFM_STOP) ? m_linearLimits.m_stopCFM[i] : info->cfm[0]; + limot.m_stopERP = (flags & BT_6DOF_FLAGS_ERP_STOP) ? m_linearLimits.m_stopERP[i] : info->erp; + if(m_useOffsetForConstraintFrame) + { + int indx1 = (i + 1) % 3; + int indx2 = (i + 2) % 3; + int rotAllowed = 1; // rotations around orthos to current axis + if(m_angularLimits[indx1].m_currentLimit && m_angularLimits[indx2].m_currentLimit) + { + rotAllowed = 0; + } + row += get_limit_motor_info2(&limot, transA,transB,linVelA,linVelB,angVelA,angVelB, info, row, axis, 0, rotAllowed); + } + else + { + row += get_limit_motor_info2(&limot, transA,transB,linVelA,linVelB,angVelA,angVelB, info, row, axis, 0); + } + } + } + return row; +} + + + +int btGeneric6DofConstraint::setAngularLimits(btConstraintInfo2 *info, int row_offset, const btTransform& transA,const btTransform& transB,const btVector3& linVelA,const btVector3& linVelB,const btVector3& angVelA,const btVector3& angVelB) +{ + btGeneric6DofConstraint * d6constraint = this; + int row = row_offset; + //solve angular limits + for (int i=0;i<3 ;i++ ) + { + if(d6constraint->getRotationalLimitMotor(i)->needApplyTorques()) + { + btVector3 axis = d6constraint->getAxis(i); + int flags = m_flags >> ((i + 3) * BT_6DOF_FLAGS_AXIS_SHIFT); + if(!(flags & BT_6DOF_FLAGS_CFM_NORM)) + { + m_angularLimits[i].m_normalCFM = info->cfm[0]; + } + if(!(flags & BT_6DOF_FLAGS_CFM_STOP)) + { + m_angularLimits[i].m_stopCFM = info->cfm[0]; + } + if(!(flags & BT_6DOF_FLAGS_ERP_STOP)) + { + m_angularLimits[i].m_stopERP = info->erp; + } + row += get_limit_motor_info2(d6constraint->getRotationalLimitMotor(i), + transA,transB,linVelA,linVelB,angVelA,angVelB, info,row,axis,1); + } + } + + return row; +} + + + + +void btGeneric6DofConstraint::updateRHS(btScalar timeStep) +{ + (void)timeStep; + +} + + + +btVector3 btGeneric6DofConstraint::getAxis(int axis_index) const +{ + return m_calculatedAxis[axis_index]; +} + + +btScalar btGeneric6DofConstraint::getRelativePivotPosition(int axisIndex) const +{ + return m_calculatedLinearDiff[axisIndex]; +} + + +btScalar btGeneric6DofConstraint::getAngle(int axisIndex) const +{ + return m_calculatedAxisAngleDiff[axisIndex]; +} + + + +void btGeneric6DofConstraint::calcAnchorPos(void) +{ + btScalar imA = m_rbA.getInvMass(); + btScalar imB = m_rbB.getInvMass(); + btScalar weight; + if(imB == btScalar(0.0)) + { + weight = btScalar(1.0); + } + else + { + weight = imA / (imA + imB); + } + const btVector3& pA = m_calculatedTransformA.getOrigin(); + const btVector3& pB = m_calculatedTransformB.getOrigin(); + m_AnchorPos = pA * weight + pB * (btScalar(1.0) - weight); + return; +} + + + +void btGeneric6DofConstraint::calculateLinearInfo() +{ + m_calculatedLinearDiff = m_calculatedTransformB.getOrigin() - m_calculatedTransformA.getOrigin(); + m_calculatedLinearDiff = m_calculatedTransformA.getBasis().inverse() * m_calculatedLinearDiff; + for(int i = 0; i < 3; i++) + { + m_linearLimits.m_currentLinearDiff[i] = m_calculatedLinearDiff[i]; + m_linearLimits.testLimitValue(i, m_calculatedLinearDiff[i]); + } +} + + + +int btGeneric6DofConstraint::get_limit_motor_info2( + btRotationalLimitMotor * limot, + const btTransform& transA,const btTransform& transB,const btVector3& linVelA,const btVector3& linVelB,const btVector3& angVelA,const btVector3& angVelB, + btConstraintInfo2 *info, int row, btVector3& ax1, int rotational,int rotAllowed) +{ + int srow = row * info->rowskip; + int powered = limot->m_enableMotor; + int limit = limot->m_currentLimit; + if (powered || limit) + { // if the joint is powered, or has joint limits, add in the extra row + btScalar *J1 = rotational ? info->m_J1angularAxis : info->m_J1linearAxis; + btScalar *J2 = rotational ? info->m_J2angularAxis : 0; + J1[srow+0] = ax1[0]; + J1[srow+1] = ax1[1]; + J1[srow+2] = ax1[2]; + if(rotational) + { + J2[srow+0] = -ax1[0]; + J2[srow+1] = -ax1[1]; + J2[srow+2] = -ax1[2]; + } + if((!rotational)) + { + if (m_useOffsetForConstraintFrame) + { + btVector3 tmpA, tmpB, relA, relB; + // get vector from bodyB to frameB in WCS + relB = m_calculatedTransformB.getOrigin() - transB.getOrigin(); + // get its projection to constraint axis + btVector3 projB = ax1 * relB.dot(ax1); + // get vector directed from bodyB to constraint axis (and orthogonal to it) + btVector3 orthoB = relB - projB; + // same for bodyA + relA = m_calculatedTransformA.getOrigin() - transA.getOrigin(); + btVector3 projA = ax1 * relA.dot(ax1); + btVector3 orthoA = relA - projA; + // get desired offset between frames A and B along constraint axis + btScalar desiredOffs = limot->m_currentPosition - limot->m_currentLimitError; + // desired vector from projection of center of bodyA to projection of center of bodyB to constraint axis + btVector3 totalDist = projA + ax1 * desiredOffs - projB; + // get offset vectors relA and relB + relA = orthoA + totalDist * m_factA; + relB = orthoB - totalDist * m_factB; + tmpA = relA.cross(ax1); + tmpB = relB.cross(ax1); + if(m_hasStaticBody && (!rotAllowed)) + { + tmpA *= m_factA; + tmpB *= m_factB; + } + int i; + for (i=0; i<3; i++) info->m_J1angularAxis[srow+i] = tmpA[i]; + for (i=0; i<3; i++) info->m_J2angularAxis[srow+i] = -tmpB[i]; + } else + { + btVector3 ltd; // Linear Torque Decoupling vector + btVector3 c = m_calculatedTransformB.getOrigin() - transA.getOrigin(); + ltd = c.cross(ax1); + info->m_J1angularAxis[srow+0] = ltd[0]; + info->m_J1angularAxis[srow+1] = ltd[1]; + info->m_J1angularAxis[srow+2] = ltd[2]; + + c = m_calculatedTransformB.getOrigin() - transB.getOrigin(); + ltd = -c.cross(ax1); + info->m_J2angularAxis[srow+0] = ltd[0]; + info->m_J2angularAxis[srow+1] = ltd[1]; + info->m_J2angularAxis[srow+2] = ltd[2]; + } + } + // if we're limited low and high simultaneously, the joint motor is + // ineffective + if (limit && (limot->m_loLimit == limot->m_hiLimit)) powered = 0; + info->m_constraintError[srow] = btScalar(0.f); + if (powered) + { + info->cfm[srow] = limot->m_normalCFM; + if(!limit) + { + btScalar tag_vel = rotational ? limot->m_targetVelocity : -limot->m_targetVelocity; + + btScalar mot_fact = getMotorFactor( limot->m_currentPosition, + limot->m_loLimit, + limot->m_hiLimit, + tag_vel, + info->fps * limot->m_stopERP); + info->m_constraintError[srow] += mot_fact * limot->m_targetVelocity; + info->m_lowerLimit[srow] = -limot->m_maxMotorForce; + info->m_upperLimit[srow] = limot->m_maxMotorForce; + } + } + if(limit) + { + btScalar k = info->fps * limot->m_stopERP; + if(!rotational) + { + info->m_constraintError[srow] += k * limot->m_currentLimitError; + } + else + { + info->m_constraintError[srow] += -k * limot->m_currentLimitError; + } + info->cfm[srow] = limot->m_stopCFM; + if (limot->m_loLimit == limot->m_hiLimit) + { // limited low and high simultaneously + info->m_lowerLimit[srow] = -SIMD_INFINITY; + info->m_upperLimit[srow] = SIMD_INFINITY; + } + else + { + if (limit == 1) + { + info->m_lowerLimit[srow] = 0; + info->m_upperLimit[srow] = SIMD_INFINITY; + } + else + { + info->m_lowerLimit[srow] = -SIMD_INFINITY; + info->m_upperLimit[srow] = 0; + } + // deal with bounce + if (limot->m_bounce > 0) + { + // calculate joint velocity + btScalar vel; + if (rotational) + { + vel = angVelA.dot(ax1); +//make sure that if no body -> angVelB == zero vec +// if (body1) + vel -= angVelB.dot(ax1); + } + else + { + vel = linVelA.dot(ax1); +//make sure that if no body -> angVelB == zero vec +// if (body1) + vel -= linVelB.dot(ax1); + } + // only apply bounce if the velocity is incoming, and if the + // resulting c[] exceeds what we already have. + if (limit == 1) + { + if (vel < 0) + { + btScalar newc = -limot->m_bounce* vel; + if (newc > info->m_constraintError[srow]) + info->m_constraintError[srow] = newc; + } + } + else + { + if (vel > 0) + { + btScalar newc = -limot->m_bounce * vel; + if (newc < info->m_constraintError[srow]) + info->m_constraintError[srow] = newc; + } + } + } + } + } + return 1; + } + else return 0; +} + + + + + + + ///override the default global value of a parameter (such as ERP or CFM), optionally provide the axis (0..5). + ///If no axis is provided, it uses the default axis for this constraint. +void btGeneric6DofConstraint::setParam(int num, btScalar value, int axis) +{ + if((axis >= 0) && (axis < 3)) + { + switch(num) + { + case BT_CONSTRAINT_STOP_ERP : + m_linearLimits.m_stopERP[axis] = value; + m_flags |= BT_6DOF_FLAGS_ERP_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + case BT_CONSTRAINT_STOP_CFM : + m_linearLimits.m_stopCFM[axis] = value; + m_flags |= BT_6DOF_FLAGS_CFM_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + case BT_CONSTRAINT_CFM : + m_linearLimits.m_normalCFM[axis] = value; + m_flags |= BT_6DOF_FLAGS_CFM_NORM << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + default : + btAssertConstrParams(0); + } + } + else if((axis >=3) && (axis < 6)) + { + switch(num) + { + case BT_CONSTRAINT_STOP_ERP : + m_angularLimits[axis - 3].m_stopERP = value; + m_flags |= BT_6DOF_FLAGS_ERP_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + case BT_CONSTRAINT_STOP_CFM : + m_angularLimits[axis - 3].m_stopCFM = value; + m_flags |= BT_6DOF_FLAGS_CFM_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + case BT_CONSTRAINT_CFM : + m_angularLimits[axis - 3].m_normalCFM = value; + m_flags |= BT_6DOF_FLAGS_CFM_NORM << (axis * BT_6DOF_FLAGS_AXIS_SHIFT); + break; + default : + btAssertConstrParams(0); + } + } + else + { + btAssertConstrParams(0); + } +} + + ///return the local value of parameter +btScalar btGeneric6DofConstraint::getParam(int num, int axis) const +{ + btScalar retVal = 0; + if((axis >= 0) && (axis < 3)) + { + switch(num) + { + case BT_CONSTRAINT_STOP_ERP : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_ERP_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_linearLimits.m_stopERP[axis]; + break; + case BT_CONSTRAINT_STOP_CFM : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_CFM_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_linearLimits.m_stopCFM[axis]; + break; + case BT_CONSTRAINT_CFM : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_CFM_NORM << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_linearLimits.m_normalCFM[axis]; + break; + default : + btAssertConstrParams(0); + } + } + else if((axis >=3) && (axis < 6)) + { + switch(num) + { + case BT_CONSTRAINT_STOP_ERP : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_ERP_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_angularLimits[axis - 3].m_stopERP; + break; + case BT_CONSTRAINT_STOP_CFM : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_CFM_STOP << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_angularLimits[axis - 3].m_stopCFM; + break; + case BT_CONSTRAINT_CFM : + btAssertConstrParams(m_flags & (BT_6DOF_FLAGS_CFM_NORM << (axis * BT_6DOF_FLAGS_AXIS_SHIFT))); + retVal = m_angularLimits[axis - 3].m_normalCFM; + break; + default : + btAssertConstrParams(0); + } + } + else + { + btAssertConstrParams(0); + } + return retVal; +} |