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Diffstat (limited to 'extern/bullet2/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp')
| -rw-r--r-- | extern/bullet2/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/extern/bullet2/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp b/extern/bullet2/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp new file mode 100644 index 00000000000..4128f504bf1 --- /dev/null +++ b/extern/bullet2/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp @@ -0,0 +1,415 @@ +/* +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. +*/ + +/* +Added by Roman Ponomarev (rponom@gmail.com) +April 04, 2008 +*/ + +//----------------------------------------------------------------------------- + +#include "btSliderConstraint.h" +#include "BulletDynamics/Dynamics/btRigidBody.h" +#include "LinearMath/btTransformUtil.h" +#include <new> + +//----------------------------------------------------------------------------- + +void btSliderConstraint::initParams() +{ + m_lowerLinLimit = btScalar(1.0); + m_upperLinLimit = btScalar(-1.0); + m_lowerAngLimit = btScalar(0.); + m_upperAngLimit = btScalar(0.); + m_softnessDirLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionDirLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingDirLin = btScalar(0.); + m_softnessDirAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionDirAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingDirAng = btScalar(0.); + m_softnessOrthoLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionOrthoLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingOrthoLin = SLIDER_CONSTRAINT_DEF_DAMPING; + m_softnessOrthoAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionOrthoAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingOrthoAng = SLIDER_CONSTRAINT_DEF_DAMPING; + m_softnessLimLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionLimLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingLimLin = SLIDER_CONSTRAINT_DEF_DAMPING; + m_softnessLimAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; + m_restitutionLimAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; + m_dampingLimAng = SLIDER_CONSTRAINT_DEF_DAMPING; + + m_poweredLinMotor = false; + m_targetLinMotorVelocity = btScalar(0.); + m_maxLinMotorForce = btScalar(0.); + m_accumulatedLinMotorImpulse = btScalar(0.0); + + m_poweredAngMotor = false; + m_targetAngMotorVelocity = btScalar(0.); + m_maxAngMotorForce = btScalar(0.); + m_accumulatedAngMotorImpulse = btScalar(0.0); + +} // btSliderConstraint::initParams() + +//----------------------------------------------------------------------------- + +btSliderConstraint::btSliderConstraint() + :btTypedConstraint(SLIDER_CONSTRAINT_TYPE), + m_useLinearReferenceFrameA(true) +{ + initParams(); +} // btSliderConstraint::btSliderConstraint() + +//----------------------------------------------------------------------------- + +btSliderConstraint::btSliderConstraint(btRigidBody& rbA, btRigidBody& rbB, const btTransform& frameInA, const btTransform& frameInB, bool useLinearReferenceFrameA) + : btTypedConstraint(SLIDER_CONSTRAINT_TYPE, rbA, rbB) + , m_frameInA(frameInA) + , m_frameInB(frameInB), + m_useLinearReferenceFrameA(useLinearReferenceFrameA) +{ + initParams(); +} // btSliderConstraint::btSliderConstraint() + +//----------------------------------------------------------------------------- + +void btSliderConstraint::buildJacobian() +{ + if(m_useLinearReferenceFrameA) + { + buildJacobianInt(m_rbA, m_rbB, m_frameInA, m_frameInB); + } + else + { + buildJacobianInt(m_rbB, m_rbA, m_frameInB, m_frameInA); + } +} // btSliderConstraint::buildJacobian() + +//----------------------------------------------------------------------------- + +void btSliderConstraint::buildJacobianInt(btRigidBody& rbA, btRigidBody& rbB, const btTransform& frameInA, const btTransform& frameInB) +{ + //calculate transforms + m_calculatedTransformA = rbA.getCenterOfMassTransform() * frameInA; + m_calculatedTransformB = rbB.getCenterOfMassTransform() * frameInB; + m_realPivotAInW = m_calculatedTransformA.getOrigin(); + m_realPivotBInW = m_calculatedTransformB.getOrigin(); + m_sliderAxis = m_calculatedTransformA.getBasis().getColumn(0); // along X + m_delta = m_realPivotBInW - m_realPivotAInW; + m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis; + m_relPosA = m_projPivotInW - rbA.getCenterOfMassPosition(); + m_relPosB = m_realPivotBInW - rbB.getCenterOfMassPosition(); + btVector3 normalWorld; + int i; + //linear part + for(i = 0; i < 3; i++) + { + normalWorld = m_calculatedTransformA.getBasis().getColumn(i); + new (&m_jacLin[i]) btJacobianEntry( + rbA.getCenterOfMassTransform().getBasis().transpose(), + rbB.getCenterOfMassTransform().getBasis().transpose(), + m_relPosA, + m_relPosB, + normalWorld, + rbA.getInvInertiaDiagLocal(), + rbA.getInvMass(), + rbB.getInvInertiaDiagLocal(), + rbB.getInvMass() + ); + m_jacLinDiagABInv[i] = btScalar(1.) / m_jacLin[i].getDiagonal(); + m_depth[i] = m_delta.dot(normalWorld); + } + testLinLimits(); + // angular part + for(i = 0; i < 3; i++) + { + normalWorld = m_calculatedTransformA.getBasis().getColumn(i); + new (&m_jacAng[i]) btJacobianEntry( + normalWorld, + rbA.getCenterOfMassTransform().getBasis().transpose(), + rbB.getCenterOfMassTransform().getBasis().transpose(), + rbA.getInvInertiaDiagLocal(), + rbB.getInvInertiaDiagLocal() + ); + } + testAngLimits(); + btVector3 axisA = m_calculatedTransformA.getBasis().getColumn(0); + m_kAngle = btScalar(1.0 )/ (rbA.computeAngularImpulseDenominator(axisA) + rbB.computeAngularImpulseDenominator(axisA)); + // clear accumulator for motors + m_accumulatedLinMotorImpulse = btScalar(0.0); + m_accumulatedAngMotorImpulse = btScalar(0.0); +} // btSliderConstraint::buildJacobianInt() + +//----------------------------------------------------------------------------- + +void btSliderConstraint::solveConstraint(btScalar timeStep) +{ + m_timeStep = timeStep; + if(m_useLinearReferenceFrameA) + { + solveConstraintInt(m_rbA, m_rbB); + } + else + { + solveConstraintInt(m_rbB, m_rbA); + } +} // btSliderConstraint::solveConstraint() + +//----------------------------------------------------------------------------- + +void btSliderConstraint::solveConstraintInt(btRigidBody& rbA, btRigidBody& rbB) +{ + int i; + // linear + btVector3 velA = rbA.getVelocityInLocalPoint(m_relPosA); + btVector3 velB = rbB.getVelocityInLocalPoint(m_relPosB); + btVector3 vel = velA - velB; + for(i = 0; i < 3; i++) + { + const btVector3& normal = m_jacLin[i].m_linearJointAxis; + btScalar rel_vel = normal.dot(vel); + // calculate positional error + btScalar depth = m_depth[i]; + // get parameters + btScalar softness = (i) ? m_softnessOrthoLin : (m_solveLinLim ? m_softnessLimLin : m_softnessDirLin); + btScalar restitution = (i) ? m_restitutionOrthoLin : (m_solveLinLim ? m_restitutionLimLin : m_restitutionDirLin); + btScalar damping = (i) ? m_dampingOrthoLin : (m_solveLinLim ? m_dampingLimLin : m_dampingDirLin); + // calcutate and apply impulse + btScalar normalImpulse = softness * (restitution * depth / m_timeStep - damping * rel_vel) * m_jacLinDiagABInv[i]; + btVector3 impulse_vector = normal * normalImpulse; + rbA.applyImpulse( impulse_vector, m_relPosA); + rbB.applyImpulse(-impulse_vector, m_relPosB); + if(m_poweredLinMotor && (!i)) + { // apply linear motor + if(m_accumulatedLinMotorImpulse < m_maxLinMotorForce) + { + btScalar desiredMotorVel = m_targetLinMotorVelocity; + btScalar motor_relvel = desiredMotorVel + rel_vel; + normalImpulse = -motor_relvel * m_jacLinDiagABInv[i]; + // clamp accumulated impulse + btScalar new_acc = m_accumulatedLinMotorImpulse + btFabs(normalImpulse); + if(new_acc > m_maxLinMotorForce) + { + new_acc = m_maxLinMotorForce; + } + btScalar del = new_acc - m_accumulatedLinMotorImpulse; + if(normalImpulse < btScalar(0.0)) + { + normalImpulse = -del; + } + else + { + normalImpulse = del; + } + m_accumulatedLinMotorImpulse = new_acc; + // apply clamped impulse + impulse_vector = normal * normalImpulse; + rbA.applyImpulse( impulse_vector, m_relPosA); + rbB.applyImpulse(-impulse_vector, m_relPosB); + } + } + } + // angular + // get axes in world space + btVector3 axisA = m_calculatedTransformA.getBasis().getColumn(0); + btVector3 axisB = m_calculatedTransformB.getBasis().getColumn(0); + + const btVector3& angVelA = rbA.getAngularVelocity(); + const btVector3& angVelB = rbB.getAngularVelocity(); + + btVector3 angVelAroundAxisA = axisA * axisA.dot(angVelA); + btVector3 angVelAroundAxisB = axisB * axisB.dot(angVelB); + + btVector3 angAorthog = angVelA - angVelAroundAxisA; + btVector3 angBorthog = angVelB - angVelAroundAxisB; + btVector3 velrelOrthog = angAorthog-angBorthog; + //solve orthogonal angular velocity correction + btScalar len = velrelOrthog.length(); + if (len > btScalar(0.00001)) + { + btVector3 normal = velrelOrthog.normalized(); + btScalar denom = rbA.computeAngularImpulseDenominator(normal) + rbB.computeAngularImpulseDenominator(normal); + velrelOrthog *= (btScalar(1.)/denom) * m_dampingOrthoAng * m_softnessOrthoAng; + } + //solve angular positional correction + btVector3 angularError = axisA.cross(axisB) *(btScalar(1.)/m_timeStep); + btScalar len2 = angularError.length(); + if (len2>btScalar(0.00001)) + { + btVector3 normal2 = angularError.normalized(); + btScalar denom2 = rbA.computeAngularImpulseDenominator(normal2) + rbB.computeAngularImpulseDenominator(normal2); + angularError *= (btScalar(1.)/denom2) * m_restitutionOrthoAng * m_softnessOrthoAng; + } + // apply impulse + rbA.applyTorqueImpulse(-velrelOrthog+angularError); + rbB.applyTorqueImpulse(velrelOrthog-angularError); + btScalar impulseMag; + //solve angular limits + if(m_solveAngLim) + { + impulseMag = (angVelB - angVelA).dot(axisA) * m_dampingLimAng + m_angDepth * m_restitutionLimAng / m_timeStep; + impulseMag *= m_kAngle * m_softnessLimAng; + } + else + { + impulseMag = (angVelB - angVelA).dot(axisA) * m_dampingDirAng + m_angDepth * m_restitutionDirAng / m_timeStep; + impulseMag *= m_kAngle * m_softnessDirAng; + } + btVector3 impulse = axisA * impulseMag; + rbA.applyTorqueImpulse(impulse); + rbB.applyTorqueImpulse(-impulse); + //apply angular motor + if(m_poweredAngMotor) + { + if(m_accumulatedAngMotorImpulse < m_maxAngMotorForce) + { + btVector3 velrel = angVelAroundAxisA - angVelAroundAxisB; + btScalar projRelVel = velrel.dot(axisA); + + btScalar desiredMotorVel = m_targetAngMotorVelocity; + btScalar motor_relvel = desiredMotorVel - projRelVel; + + btScalar angImpulse = m_kAngle * motor_relvel; + // clamp accumulated impulse + btScalar new_acc = m_accumulatedAngMotorImpulse + btFabs(angImpulse); + if(new_acc > m_maxAngMotorForce) + { + new_acc = m_maxAngMotorForce; + } + btScalar del = new_acc - m_accumulatedAngMotorImpulse; + if(angImpulse < btScalar(0.0)) + { + angImpulse = -del; + } + else + { + angImpulse = del; + } + m_accumulatedAngMotorImpulse = new_acc; + // apply clamped impulse + btVector3 motorImp = angImpulse * axisA; + m_rbA.applyTorqueImpulse(motorImp); + m_rbB.applyTorqueImpulse(-motorImp); + } + } +} // btSliderConstraint::solveConstraint() + +//----------------------------------------------------------------------------- + +//----------------------------------------------------------------------------- + +void btSliderConstraint::calculateTransforms(void){ + if(m_useLinearReferenceFrameA) + { + m_calculatedTransformA = m_rbA.getCenterOfMassTransform() * m_frameInA; + m_calculatedTransformB = m_rbB.getCenterOfMassTransform() * m_frameInB; + } + else + { + m_calculatedTransformA = m_rbB.getCenterOfMassTransform() * m_frameInB; + m_calculatedTransformB = m_rbA.getCenterOfMassTransform() * m_frameInA; + } + m_realPivotAInW = m_calculatedTransformA.getOrigin(); + m_realPivotBInW = m_calculatedTransformB.getOrigin(); + m_sliderAxis = m_calculatedTransformA.getBasis().getColumn(0); // along X + m_delta = m_realPivotBInW - m_realPivotAInW; + m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis; + btVector3 normalWorld; + int i; + //linear part + for(i = 0; i < 3; i++) + { + normalWorld = m_calculatedTransformA.getBasis().getColumn(i); + m_depth[i] = m_delta.dot(normalWorld); + } +} // btSliderConstraint::calculateTransforms() + +//----------------------------------------------------------------------------- + +void btSliderConstraint::testLinLimits(void) +{ + m_solveLinLim = false; + m_linPos = m_depth[0]; + if(m_lowerLinLimit <= m_upperLinLimit) + { + if(m_depth[0] > m_upperLinLimit) + { + m_depth[0] -= m_upperLinLimit; + m_solveLinLim = true; + } + else if(m_depth[0] < m_lowerLinLimit) + { + m_depth[0] -= m_lowerLinLimit; + m_solveLinLim = true; + } + else + { + m_depth[0] = btScalar(0.); + } + } + else + { + m_depth[0] = btScalar(0.); + } +} // btSliderConstraint::testLinLimits() + +//----------------------------------------------------------------------------- + + +void btSliderConstraint::testAngLimits(void) +{ + m_angDepth = btScalar(0.); + m_solveAngLim = false; + if(m_lowerAngLimit <= m_upperAngLimit) + { + const btVector3 axisA0 = m_calculatedTransformA.getBasis().getColumn(1); + const btVector3 axisA1 = m_calculatedTransformA.getBasis().getColumn(2); + const btVector3 axisB0 = m_calculatedTransformB.getBasis().getColumn(1); + btScalar rot = btAtan2Fast(axisB0.dot(axisA1), axisB0.dot(axisA0)); + if(rot < m_lowerAngLimit) + { + m_angDepth = rot - m_lowerAngLimit; + m_solveAngLim = true; + } + else if(rot > m_upperAngLimit) + { + m_angDepth = rot - m_upperAngLimit; + m_solveAngLim = true; + } + } +} // btSliderConstraint::testAngLimits() + + +//----------------------------------------------------------------------------- + + + +btVector3 btSliderConstraint::getAncorInA(void) +{ + btVector3 ancorInA; + ancorInA = m_realPivotAInW + (m_lowerLinLimit + m_upperLinLimit) * btScalar(0.5) * m_sliderAxis; + ancorInA = m_rbA.getCenterOfMassTransform().inverse() * ancorInA; + return ancorInA; +} // btSliderConstraint::getAncorInA() + +//----------------------------------------------------------------------------- + +btVector3 btSliderConstraint::getAncorInB(void) +{ + btVector3 ancorInB; + ancorInB = m_frameInB.getOrigin(); + return ancorInB; +} // btSliderConstraint::getAncorInB(); |