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Diffstat (limited to 'thirdparty/bullet/BulletDynamics/Featherstone/btMultiBody.cpp')
| -rw-r--r-- | thirdparty/bullet/BulletDynamics/Featherstone/btMultiBody.cpp | 2043 |
1 files changed, 2043 insertions, 0 deletions
diff --git a/thirdparty/bullet/BulletDynamics/Featherstone/btMultiBody.cpp b/thirdparty/bullet/BulletDynamics/Featherstone/btMultiBody.cpp new file mode 100644 index 0000000000..62865e0c78 --- /dev/null +++ b/thirdparty/bullet/BulletDynamics/Featherstone/btMultiBody.cpp @@ -0,0 +1,2043 @@ +/* + * PURPOSE: + * Class representing an articulated rigid body. Stores the body's + * current state, allows forces and torques to be set, handles + * timestepping and implements Featherstone's algorithm. + * + * COPYRIGHT: + * Copyright (C) Stephen Thompson, <stephen@solarflare.org.uk>, 2011-2013 + * Portions written By Erwin Coumans: connection to LCP solver, various multibody constraints, replacing Eigen math library by Bullet LinearMath and a dedicated 6x6 matrix inverse (solveImatrix) + * Portions written By Jakub Stepien: support for multi-DOF constraints, introduction of spatial algebra and several other improvements + + 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 "btMultiBody.h" +#include "btMultiBodyLink.h" +#include "btMultiBodyLinkCollider.h" +#include "btMultiBodyJointFeedback.h" +#include "LinearMath/btTransformUtil.h" +#include "LinearMath/btSerializer.h" +//#include "Bullet3Common/b3Logging.h" +// #define INCLUDE_GYRO_TERM + +///todo: determine if we need these options. If so, make a proper API, otherwise delete those globals +bool gJointFeedbackInWorldSpace = false; +bool gJointFeedbackInJointFrame = false; + +namespace { + const btScalar SLEEP_EPSILON = btScalar(0.05); // this is a squared velocity (m^2 s^-2) + const btScalar SLEEP_TIMEOUT = btScalar(2); // in seconds +} + +namespace { + void SpatialTransform(const btMatrix3x3 &rotation_matrix, // rotates vectors in 'from' frame to vectors in 'to' frame + const btVector3 &displacement, // vector from origin of 'from' frame to origin of 'to' frame, in 'to' coordinates + const btVector3 &top_in, // top part of input vector + const btVector3 &bottom_in, // bottom part of input vector + btVector3 &top_out, // top part of output vector + btVector3 &bottom_out) // bottom part of output vector + { + top_out = rotation_matrix * top_in; + bottom_out = -displacement.cross(top_out) + rotation_matrix * bottom_in; + } + +#if 0 + void InverseSpatialTransform(const btMatrix3x3 &rotation_matrix, + const btVector3 &displacement, + const btVector3 &top_in, + const btVector3 &bottom_in, + btVector3 &top_out, + btVector3 &bottom_out) + { + top_out = rotation_matrix.transpose() * top_in; + bottom_out = rotation_matrix.transpose() * (bottom_in + displacement.cross(top_in)); + } + + btScalar SpatialDotProduct(const btVector3 &a_top, + const btVector3 &a_bottom, + const btVector3 &b_top, + const btVector3 &b_bottom) + { + return a_bottom.dot(b_top) + a_top.dot(b_bottom); + } + + void SpatialCrossProduct(const btVector3 &a_top, + const btVector3 &a_bottom, + const btVector3 &b_top, + const btVector3 &b_bottom, + btVector3 &top_out, + btVector3 &bottom_out) + { + top_out = a_top.cross(b_top); + bottom_out = a_bottom.cross(b_top) + a_top.cross(b_bottom); + } +#endif + +} + + +// +// Implementation of class btMultiBody +// + +btMultiBody::btMultiBody(int n_links, + btScalar mass, + const btVector3 &inertia, + bool fixedBase, + bool canSleep, + bool /*deprecatedUseMultiDof*/) + : + m_baseCollider(0), + m_baseName(0), + m_basePos(0,0,0), + m_baseQuat(0, 0, 0, 1), + m_baseMass(mass), + m_baseInertia(inertia), + + m_fixedBase(fixedBase), + m_awake(true), + m_canSleep(canSleep), + m_sleepTimer(0), + m_userObjectPointer(0), + m_userIndex2(-1), + m_userIndex(-1), + m_linearDamping(0.04f), + m_angularDamping(0.04f), + m_useGyroTerm(true), + m_maxAppliedImpulse(1000.f), + m_maxCoordinateVelocity(100.f), + m_hasSelfCollision(true), + __posUpdated(false), + m_dofCount(0), + m_posVarCnt(0), + m_useRK4(false), + m_useGlobalVelocities(false), + m_internalNeedsJointFeedback(false) +{ + m_cachedInertiaTopLeft.setValue(0,0,0,0,0,0,0,0,0); + m_cachedInertiaTopRight.setValue(0,0,0,0,0,0,0,0,0); + m_cachedInertiaLowerLeft.setValue(0,0,0,0,0,0,0,0,0); + m_cachedInertiaLowerRight.setValue(0,0,0,0,0,0,0,0,0); + m_cachedInertiaValid=false; + + m_links.resize(n_links); + m_matrixBuf.resize(n_links + 1); + + m_baseForce.setValue(0, 0, 0); + m_baseTorque.setValue(0, 0, 0); +} + +btMultiBody::~btMultiBody() +{ +} + +void btMultiBody::setupFixed(int i, + btScalar mass, + const btVector3 &inertia, + int parent, + const btQuaternion &rotParentToThis, + const btVector3 &parentComToThisPivotOffset, + const btVector3 &thisPivotToThisComOffset, bool /*deprecatedDisableParentCollision*/) +{ + + m_links[i].m_mass = mass; + m_links[i].m_inertiaLocal = inertia; + m_links[i].m_parent = parent; + m_links[i].setAxisTop(0, 0., 0., 0.); + m_links[i].setAxisBottom(0, btVector3(0,0,0)); + m_links[i].m_zeroRotParentToThis = rotParentToThis; + m_links[i].m_dVector = thisPivotToThisComOffset; + m_links[i].m_eVector = parentComToThisPivotOffset; + + m_links[i].m_jointType = btMultibodyLink::eFixed; + m_links[i].m_dofCount = 0; + m_links[i].m_posVarCount = 0; + + m_links[i].m_flags |=BT_MULTIBODYLINKFLAGS_DISABLE_PARENT_COLLISION; + + m_links[i].updateCacheMultiDof(); + + updateLinksDofOffsets(); + +} + + +void btMultiBody::setupPrismatic(int i, + btScalar mass, + const btVector3 &inertia, + int parent, + const btQuaternion &rotParentToThis, + const btVector3 &jointAxis, + const btVector3 &parentComToThisPivotOffset, + const btVector3 &thisPivotToThisComOffset, + bool disableParentCollision) +{ + m_dofCount += 1; + m_posVarCnt += 1; + + m_links[i].m_mass = mass; + m_links[i].m_inertiaLocal = inertia; + m_links[i].m_parent = parent; + m_links[i].m_zeroRotParentToThis = rotParentToThis; + m_links[i].setAxisTop(0, 0., 0., 0.); + m_links[i].setAxisBottom(0, jointAxis); + m_links[i].m_eVector = parentComToThisPivotOffset; + m_links[i].m_dVector = thisPivotToThisComOffset; + m_links[i].m_cachedRotParentToThis = rotParentToThis; + + m_links[i].m_jointType = btMultibodyLink::ePrismatic; + m_links[i].m_dofCount = 1; + m_links[i].m_posVarCount = 1; + m_links[i].m_jointPos[0] = 0.f; + m_links[i].m_jointTorque[0] = 0.f; + + if (disableParentCollision) + m_links[i].m_flags |=BT_MULTIBODYLINKFLAGS_DISABLE_PARENT_COLLISION; + // + + m_links[i].updateCacheMultiDof(); + + updateLinksDofOffsets(); +} + +void btMultiBody::setupRevolute(int i, + btScalar mass, + const btVector3 &inertia, + int parent, + const btQuaternion &rotParentToThis, + const btVector3 &jointAxis, + const btVector3 &parentComToThisPivotOffset, + const btVector3 &thisPivotToThisComOffset, + bool disableParentCollision) +{ + m_dofCount += 1; + m_posVarCnt += 1; + + m_links[i].m_mass = mass; + m_links[i].m_inertiaLocal = inertia; + m_links[i].m_parent = parent; + m_links[i].m_zeroRotParentToThis = rotParentToThis; + m_links[i].setAxisTop(0, jointAxis); + m_links[i].setAxisBottom(0, jointAxis.cross(thisPivotToThisComOffset)); + m_links[i].m_dVector = thisPivotToThisComOffset; + m_links[i].m_eVector = parentComToThisPivotOffset; + + m_links[i].m_jointType = btMultibodyLink::eRevolute; + m_links[i].m_dofCount = 1; + m_links[i].m_posVarCount = 1; + m_links[i].m_jointPos[0] = 0.f; + m_links[i].m_jointTorque[0] = 0.f; + + if (disableParentCollision) + m_links[i].m_flags |=BT_MULTIBODYLINKFLAGS_DISABLE_PARENT_COLLISION; + // + m_links[i].updateCacheMultiDof(); + // + updateLinksDofOffsets(); +} + + + +void btMultiBody::setupSpherical(int i, + btScalar mass, + const btVector3 &inertia, + int parent, + const btQuaternion &rotParentToThis, + const btVector3 &parentComToThisPivotOffset, + const btVector3 &thisPivotToThisComOffset, + bool disableParentCollision) +{ + + m_dofCount += 3; + m_posVarCnt += 4; + + m_links[i].m_mass = mass; + m_links[i].m_inertiaLocal = inertia; + m_links[i].m_parent = parent; + m_links[i].m_zeroRotParentToThis = rotParentToThis; + m_links[i].m_dVector = thisPivotToThisComOffset; + m_links[i].m_eVector = parentComToThisPivotOffset; + + m_links[i].m_jointType = btMultibodyLink::eSpherical; + m_links[i].m_dofCount = 3; + m_links[i].m_posVarCount = 4; + m_links[i].setAxisTop(0, 1.f, 0.f, 0.f); + m_links[i].setAxisTop(1, 0.f, 1.f, 0.f); + m_links[i].setAxisTop(2, 0.f, 0.f, 1.f); + m_links[i].setAxisBottom(0, m_links[i].getAxisTop(0).cross(thisPivotToThisComOffset)); + m_links[i].setAxisBottom(1, m_links[i].getAxisTop(1).cross(thisPivotToThisComOffset)); + m_links[i].setAxisBottom(2, m_links[i].getAxisTop(2).cross(thisPivotToThisComOffset)); + m_links[i].m_jointPos[0] = m_links[i].m_jointPos[1] = m_links[i].m_jointPos[2] = 0.f; m_links[i].m_jointPos[3] = 1.f; + m_links[i].m_jointTorque[0] = m_links[i].m_jointTorque[1] = m_links[i].m_jointTorque[2] = 0.f; + + + if (disableParentCollision) + m_links[i].m_flags |=BT_MULTIBODYLINKFLAGS_DISABLE_PARENT_COLLISION; + // + m_links[i].updateCacheMultiDof(); + // + updateLinksDofOffsets(); +} + +void btMultiBody::setupPlanar(int i, + btScalar mass, + const btVector3 &inertia, + int parent, + const btQuaternion &rotParentToThis, + const btVector3 &rotationAxis, + const btVector3 &parentComToThisComOffset, + bool disableParentCollision) +{ + + m_dofCount += 3; + m_posVarCnt += 3; + + m_links[i].m_mass = mass; + m_links[i].m_inertiaLocal = inertia; + m_links[i].m_parent = parent; + m_links[i].m_zeroRotParentToThis = rotParentToThis; + m_links[i].m_dVector.setZero(); + m_links[i].m_eVector = parentComToThisComOffset; + + // + btVector3 vecNonParallelToRotAxis(1, 0, 0); + if(rotationAxis.normalized().dot(vecNonParallelToRotAxis) > 0.999) + vecNonParallelToRotAxis.setValue(0, 1, 0); + // + + m_links[i].m_jointType = btMultibodyLink::ePlanar; + m_links[i].m_dofCount = 3; + m_links[i].m_posVarCount = 3; + btVector3 n=rotationAxis.normalized(); + m_links[i].setAxisTop(0, n[0],n[1],n[2]); + m_links[i].setAxisTop(1,0,0,0); + m_links[i].setAxisTop(2,0,0,0); + m_links[i].setAxisBottom(0,0,0,0); + btVector3 cr = m_links[i].getAxisTop(0).cross(vecNonParallelToRotAxis); + m_links[i].setAxisBottom(1,cr[0],cr[1],cr[2]); + cr = m_links[i].getAxisBottom(1).cross(m_links[i].getAxisTop(0)); + m_links[i].setAxisBottom(2,cr[0],cr[1],cr[2]); + m_links[i].m_jointPos[0] = m_links[i].m_jointPos[1] = m_links[i].m_jointPos[2] = 0.f; + m_links[i].m_jointTorque[0] = m_links[i].m_jointTorque[1] = m_links[i].m_jointTorque[2] = 0.f; + + if (disableParentCollision) + m_links[i].m_flags |=BT_MULTIBODYLINKFLAGS_DISABLE_PARENT_COLLISION; + // + m_links[i].updateCacheMultiDof(); + // + updateLinksDofOffsets(); +} + +void btMultiBody::finalizeMultiDof() +{ + m_deltaV.resize(0); + m_deltaV.resize(6 + m_dofCount); + m_realBuf.resize(6 + m_dofCount + m_dofCount*m_dofCount + 6 + m_dofCount); //m_dofCount for joint-space vels + m_dofCount^2 for "D" matrices + delta-pos vector (6 base "vels" + joint "vels") + m_vectorBuf.resize(2 * m_dofCount); //two 3-vectors (i.e. one six-vector) for each system dof ("h" matrices) + for (int i=0;i<m_vectorBuf.size();i++) + { + m_vectorBuf[i].setValue(0,0,0); + } + updateLinksDofOffsets(); +} + +int btMultiBody::getParent(int i) const +{ + return m_links[i].m_parent; +} + +btScalar btMultiBody::getLinkMass(int i) const +{ + return m_links[i].m_mass; +} + +const btVector3 & btMultiBody::getLinkInertia(int i) const +{ + return m_links[i].m_inertiaLocal; +} + +btScalar btMultiBody::getJointPos(int i) const +{ + return m_links[i].m_jointPos[0]; +} + +btScalar btMultiBody::getJointVel(int i) const +{ + return m_realBuf[6 + m_links[i].m_dofOffset]; +} + +btScalar * btMultiBody::getJointPosMultiDof(int i) +{ + return &m_links[i].m_jointPos[0]; +} + +btScalar * btMultiBody::getJointVelMultiDof(int i) +{ + return &m_realBuf[6 + m_links[i].m_dofOffset]; +} + +const btScalar * btMultiBody::getJointPosMultiDof(int i) const +{ + return &m_links[i].m_jointPos[0]; +} + +const btScalar * btMultiBody::getJointVelMultiDof(int i) const +{ + return &m_realBuf[6 + m_links[i].m_dofOffset]; +} + + +void btMultiBody::setJointPos(int i, btScalar q) +{ + m_links[i].m_jointPos[0] = q; + m_links[i].updateCacheMultiDof(); +} + +void btMultiBody::setJointPosMultiDof(int i, btScalar *q) +{ + for(int pos = 0; pos < m_links[i].m_posVarCount; ++pos) + m_links[i].m_jointPos[pos] = q[pos]; + + m_links[i].updateCacheMultiDof(); +} + +void btMultiBody::setJointVel(int i, btScalar qdot) +{ + m_realBuf[6 + m_links[i].m_dofOffset] = qdot; +} + +void btMultiBody::setJointVelMultiDof(int i, btScalar *qdot) +{ + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + m_realBuf[6 + m_links[i].m_dofOffset + dof] = qdot[dof]; +} + +const btVector3 & btMultiBody::getRVector(int i) const +{ + return m_links[i].m_cachedRVector; +} + +const btQuaternion & btMultiBody::getParentToLocalRot(int i) const +{ + return m_links[i].m_cachedRotParentToThis; +} + +btVector3 btMultiBody::localPosToWorld(int i, const btVector3 &local_pos) const +{ + btAssert(i>=-1); + btAssert(i<m_links.size()); + if ((i<-1) || (i>=m_links.size())) + { + return btVector3(SIMD_INFINITY,SIMD_INFINITY,SIMD_INFINITY); + } + + btVector3 result = local_pos; + while (i != -1) { + // 'result' is in frame i. transform it to frame parent(i) + result += getRVector(i); + result = quatRotate(getParentToLocalRot(i).inverse(),result); + i = getParent(i); + } + + // 'result' is now in the base frame. transform it to world frame + result = quatRotate(getWorldToBaseRot().inverse() ,result); + result += getBasePos(); + + return result; +} + +btVector3 btMultiBody::worldPosToLocal(int i, const btVector3 &world_pos) const +{ + btAssert(i>=-1); + btAssert(i<m_links.size()); + if ((i<-1) || (i>=m_links.size())) + { + return btVector3(SIMD_INFINITY,SIMD_INFINITY,SIMD_INFINITY); + } + + if (i == -1) { + // world to base + return quatRotate(getWorldToBaseRot(),(world_pos - getBasePos())); + } else { + // find position in parent frame, then transform to current frame + return quatRotate(getParentToLocalRot(i),worldPosToLocal(getParent(i), world_pos)) - getRVector(i); + } +} + +btVector3 btMultiBody::localDirToWorld(int i, const btVector3 &local_dir) const +{ + btAssert(i>=-1); + btAssert(i<m_links.size()); + if ((i<-1) || (i>=m_links.size())) + { + return btVector3(SIMD_INFINITY,SIMD_INFINITY,SIMD_INFINITY); + } + + + btVector3 result = local_dir; + while (i != -1) { + result = quatRotate(getParentToLocalRot(i).inverse() , result); + i = getParent(i); + } + result = quatRotate(getWorldToBaseRot().inverse() , result); + return result; +} + +btVector3 btMultiBody::worldDirToLocal(int i, const btVector3 &world_dir) const +{ + btAssert(i>=-1); + btAssert(i<m_links.size()); + if ((i<-1) || (i>=m_links.size())) + { + return btVector3(SIMD_INFINITY,SIMD_INFINITY,SIMD_INFINITY); + } + + if (i == -1) { + return quatRotate(getWorldToBaseRot(), world_dir); + } else { + return quatRotate(getParentToLocalRot(i) ,worldDirToLocal(getParent(i), world_dir)); + } +} + +btMatrix3x3 btMultiBody::localFrameToWorld(int i, const btMatrix3x3 &local_frame) const +{ + btMatrix3x3 result = local_frame; + btVector3 frameInWorld0 = localDirToWorld(i, local_frame.getColumn(0)); + btVector3 frameInWorld1 = localDirToWorld(i, local_frame.getColumn(1)); + btVector3 frameInWorld2 = localDirToWorld(i, local_frame.getColumn(2)); + result.setValue(frameInWorld0[0], frameInWorld1[0], frameInWorld2[0], frameInWorld0[1], frameInWorld1[1], frameInWorld2[1], frameInWorld0[2], frameInWorld1[2], frameInWorld2[2]); + return result; +} + +void btMultiBody::compTreeLinkVelocities(btVector3 *omega, btVector3 *vel) const +{ + int num_links = getNumLinks(); + // Calculates the velocities of each link (and the base) in its local frame + omega[0] = quatRotate(m_baseQuat ,getBaseOmega()); + vel[0] = quatRotate(m_baseQuat ,getBaseVel()); + + for (int i = 0; i < num_links; ++i) + { + const int parent = m_links[i].m_parent; + + // transform parent vel into this frame, store in omega[i+1], vel[i+1] + SpatialTransform(btMatrix3x3(m_links[i].m_cachedRotParentToThis), m_links[i].m_cachedRVector, + omega[parent+1], vel[parent+1], + omega[i+1], vel[i+1]); + + // now add qidot * shat_i + //only supported for revolute/prismatic joints, todo: spherical and planar joints + switch(m_links[i].m_jointType) + { + case btMultibodyLink::ePrismatic: + case btMultibodyLink::eRevolute: + { + btVector3 axisTop = m_links[i].getAxisTop(0); + btVector3 axisBottom = m_links[i].getAxisBottom(0); + btScalar jointVel = getJointVel(i); + omega[i+1] += jointVel * axisTop; + vel[i+1] += jointVel * axisBottom; + break; + } + default: + { + } + } + } +} + +btScalar btMultiBody::getKineticEnergy() const +{ + int num_links = getNumLinks(); + // TODO: would be better not to allocate memory here + btAlignedObjectArray<btVector3> omega;omega.resize(num_links+1); + btAlignedObjectArray<btVector3> vel;vel.resize(num_links+1); + compTreeLinkVelocities(&omega[0], &vel[0]); + + // we will do the factor of 0.5 at the end + btScalar result = m_baseMass * vel[0].dot(vel[0]); + result += omega[0].dot(m_baseInertia * omega[0]); + + for (int i = 0; i < num_links; ++i) { + result += m_links[i].m_mass * vel[i+1].dot(vel[i+1]); + result += omega[i+1].dot(m_links[i].m_inertiaLocal * omega[i+1]); + } + + return 0.5f * result; +} + +btVector3 btMultiBody::getAngularMomentum() const +{ + int num_links = getNumLinks(); + // TODO: would be better not to allocate memory here + btAlignedObjectArray<btVector3> omega;omega.resize(num_links+1); + btAlignedObjectArray<btVector3> vel;vel.resize(num_links+1); + btAlignedObjectArray<btQuaternion> rot_from_world;rot_from_world.resize(num_links+1); + compTreeLinkVelocities(&omega[0], &vel[0]); + + rot_from_world[0] = m_baseQuat; + btVector3 result = quatRotate(rot_from_world[0].inverse() , (m_baseInertia * omega[0])); + + for (int i = 0; i < num_links; ++i) { + rot_from_world[i+1] = m_links[i].m_cachedRotParentToThis * rot_from_world[m_links[i].m_parent+1]; + result += (quatRotate(rot_from_world[i+1].inverse() , (m_links[i].m_inertiaLocal * omega[i+1]))); + } + + return result; +} + +void btMultiBody::clearConstraintForces() +{ + m_baseConstraintForce.setValue(0, 0, 0); + m_baseConstraintTorque.setValue(0, 0, 0); + + + for (int i = 0; i < getNumLinks(); ++i) { + m_links[i].m_appliedConstraintForce.setValue(0, 0, 0); + m_links[i].m_appliedConstraintTorque.setValue(0, 0, 0); + } +} +void btMultiBody::clearForcesAndTorques() +{ + m_baseForce.setValue(0, 0, 0); + m_baseTorque.setValue(0, 0, 0); + + + for (int i = 0; i < getNumLinks(); ++i) { + m_links[i].m_appliedForce.setValue(0, 0, 0); + m_links[i].m_appliedTorque.setValue(0, 0, 0); + m_links[i].m_jointTorque[0] = m_links[i].m_jointTorque[1] = m_links[i].m_jointTorque[2] = m_links[i].m_jointTorque[3] = m_links[i].m_jointTorque[4] = m_links[i].m_jointTorque[5] = 0.f; + } +} + +void btMultiBody::clearVelocities() +{ + for (int i = 0; i < 6 + getNumDofs(); ++i) + { + m_realBuf[i] = 0.f; + } +} +void btMultiBody::addLinkForce(int i, const btVector3 &f) +{ + m_links[i].m_appliedForce += f; +} + +void btMultiBody::addLinkTorque(int i, const btVector3 &t) +{ + m_links[i].m_appliedTorque += t; +} + +void btMultiBody::addLinkConstraintForce(int i, const btVector3 &f) +{ + m_links[i].m_appliedConstraintForce += f; +} + +void btMultiBody::addLinkConstraintTorque(int i, const btVector3 &t) +{ + m_links[i].m_appliedConstraintTorque += t; +} + + + +void btMultiBody::addJointTorque(int i, btScalar Q) +{ + m_links[i].m_jointTorque[0] += Q; +} + +void btMultiBody::addJointTorqueMultiDof(int i, int dof, btScalar Q) +{ + m_links[i].m_jointTorque[dof] += Q; +} + +void btMultiBody::addJointTorqueMultiDof(int i, const btScalar *Q) +{ + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + m_links[i].m_jointTorque[dof] = Q[dof]; +} + +const btVector3 & btMultiBody::getLinkForce(int i) const +{ + return m_links[i].m_appliedForce; +} + +const btVector3 & btMultiBody::getLinkTorque(int i) const +{ + return m_links[i].m_appliedTorque; +} + +btScalar btMultiBody::getJointTorque(int i) const +{ + return m_links[i].m_jointTorque[0]; +} + +btScalar * btMultiBody::getJointTorqueMultiDof(int i) +{ + return &m_links[i].m_jointTorque[0]; +} + +inline btMatrix3x3 outerProduct(const btVector3& v0, const btVector3& v1) //renamed it from vecMulVecTranspose (http://en.wikipedia.org/wiki/Outer_product); maybe it should be moved to btVector3 like dot and cross? +{ + btVector3 row0 = btVector3( + v0.x() * v1.x(), + v0.x() * v1.y(), + v0.x() * v1.z()); + btVector3 row1 = btVector3( + v0.y() * v1.x(), + v0.y() * v1.y(), + v0.y() * v1.z()); + btVector3 row2 = btVector3( + v0.z() * v1.x(), + v0.z() * v1.y(), + v0.z() * v1.z()); + + btMatrix3x3 m(row0[0],row0[1],row0[2], + row1[0],row1[1],row1[2], + row2[0],row2[1],row2[2]); + return m; +} + +#define vecMulVecTranspose(v0, v1Transposed) outerProduct(v0, v1Transposed) +// + +void btMultiBody::computeAccelerationsArticulatedBodyAlgorithmMultiDof(btScalar dt, + btAlignedObjectArray<btScalar> &scratch_r, + btAlignedObjectArray<btVector3> &scratch_v, + btAlignedObjectArray<btMatrix3x3> &scratch_m, + bool isConstraintPass) +{ + // Implement Featherstone's algorithm to calculate joint accelerations (q_double_dot) + // and the base linear & angular accelerations. + + // We apply damping forces in this routine as well as any external forces specified by the + // caller (via addBaseForce etc). + + // output should point to an array of 6 + num_links reals. + // Format is: 3 angular accelerations (in world frame), 3 linear accelerations (in world frame), + // num_links joint acceleration values. + + // We added support for multi degree of freedom (multi dof) joints. + // In addition we also can compute the joint reaction forces. This is performed in a second pass, + // so that we can include the effect of the constraint solver forces (computed in the PGS LCP solver) + + m_internalNeedsJointFeedback = false; + + int num_links = getNumLinks(); + + const btScalar DAMPING_K1_LINEAR = m_linearDamping; + const btScalar DAMPING_K2_LINEAR = m_linearDamping; + + const btScalar DAMPING_K1_ANGULAR = m_angularDamping; + const btScalar DAMPING_K2_ANGULAR= m_angularDamping; + + btVector3 base_vel = getBaseVel(); + btVector3 base_omega = getBaseOmega(); + + // Temporary matrices/vectors -- use scratch space from caller + // so that we don't have to keep reallocating every frame + + scratch_r.resize(2*m_dofCount + 6); //multidof? ("Y"s use it and it is used to store qdd) => 2 x m_dofCount + scratch_v.resize(8*num_links + 6); + scratch_m.resize(4*num_links + 4); + + //btScalar * r_ptr = &scratch_r[0]; + btScalar * output = &scratch_r[m_dofCount]; // "output" holds the q_double_dot results + btVector3 * v_ptr = &scratch_v[0]; + + // vhat_i (top = angular, bottom = linear part) + btSpatialMotionVector *spatVel = (btSpatialMotionVector *)v_ptr; + v_ptr += num_links * 2 + 2; + // + // zhat_i^A + btSpatialForceVector * zeroAccSpatFrc = (btSpatialForceVector *)v_ptr; + v_ptr += num_links * 2 + 2; + // + // chat_i (note NOT defined for the base) + btSpatialMotionVector * spatCoriolisAcc = (btSpatialMotionVector *)v_ptr; + v_ptr += num_links * 2; + // + // Ihat_i^A. + btSymmetricSpatialDyad * spatInertia = (btSymmetricSpatialDyad *)&scratch_m[num_links + 1]; + + // Cached 3x3 rotation matrices from parent frame to this frame. + btMatrix3x3 * rot_from_parent = &m_matrixBuf[0]; + btMatrix3x3 * rot_from_world = &scratch_m[0]; + + // hhat_i, ahat_i + // hhat is NOT stored for the base (but ahat is) + btSpatialForceVector * h = (btSpatialForceVector *)(m_dofCount > 0 ? &m_vectorBuf[0] : 0); + btSpatialMotionVector * spatAcc = (btSpatialMotionVector *)v_ptr; + v_ptr += num_links * 2 + 2; + // + // Y_i, invD_i + btScalar * invD = m_dofCount > 0 ? &m_realBuf[6 + m_dofCount] : 0; + btScalar * Y = &scratch_r[0]; + // + //aux variables + btSpatialMotionVector spatJointVel; //spatial velocity due to the joint motion (i.e. without predecessors' influence) + btScalar D[36]; //"D" matrix; it's dofxdof for each body so asingle 6x6 D matrix will do + btScalar invD_times_Y[6]; //D^{-1} * Y [dofxdof x dofx1 = dofx1] <=> D^{-1} * u; better moved to buffers since it is recalced in calcAccelerationDeltasMultiDof; num_dof of btScalar would cover all bodies + btSpatialMotionVector result; //holds results of the SolveImatrix op; it is a spatial motion vector (accel) + btScalar Y_minus_hT_a[6]; //Y - h^{T} * a; it's dofx1 for each body so a single 6x1 temp is enough + btSpatialForceVector spatForceVecTemps[6]; //6 temporary spatial force vectors + btSpatialTransformationMatrix fromParent; //spatial transform from parent to child + btSymmetricSpatialDyad dyadTemp; //inertia matrix temp + btSpatialTransformationMatrix fromWorld; + fromWorld.m_trnVec.setZero(); + ///////////////// + + // ptr to the joint accel part of the output + btScalar * joint_accel = output + 6; + + // Start of the algorithm proper. + + // First 'upward' loop. + // Combines CompTreeLinkVelocities and InitTreeLinks from Mirtich. + + rot_from_parent[0] = btMatrix3x3(m_baseQuat); //m_baseQuat assumed to be alias!? + + //create the vector of spatial velocity of the base by transforming global-coor linear and angular velocities into base-local coordinates + spatVel[0].setVector(rot_from_parent[0] * base_omega, rot_from_parent[0] * base_vel); + + if (m_fixedBase) + { + zeroAccSpatFrc[0].setZero(); + } + else + { + btVector3 baseForce = isConstraintPass? m_baseConstraintForce : m_baseForce; + btVector3 baseTorque = isConstraintPass? m_baseConstraintTorque : m_baseTorque; + //external forces + zeroAccSpatFrc[0].setVector(-(rot_from_parent[0] * baseTorque), -(rot_from_parent[0] * baseForce)); + + //adding damping terms (only) + btScalar linDampMult = 1., angDampMult = 1.; + zeroAccSpatFrc[0].addVector(angDampMult * m_baseInertia * spatVel[0].getAngular() * (DAMPING_K1_ANGULAR + DAMPING_K2_ANGULAR * spatVel[0].getAngular().safeNorm()), + linDampMult * m_baseMass * spatVel[0].getLinear() * (DAMPING_K1_LINEAR + DAMPING_K2_LINEAR * spatVel[0].getLinear().safeNorm())); + + // + //p += vhat x Ihat vhat - done in a simpler way + if (m_useGyroTerm) + zeroAccSpatFrc[0].addAngular(spatVel[0].getAngular().cross(m_baseInertia * spatVel[0].getAngular())); + // + zeroAccSpatFrc[0].addLinear(m_baseMass * spatVel[0].getAngular().cross(spatVel[0].getLinear())); + } + + + //init the spatial AB inertia (it has the simple form thanks to choosing local body frames origins at their COMs) + spatInertia[0].setMatrix( btMatrix3x3(0,0,0,0,0,0,0,0,0), + // + btMatrix3x3(m_baseMass, 0, 0, + 0, m_baseMass, 0, + 0, 0, m_baseMass), + // + btMatrix3x3(m_baseInertia[0], 0, 0, + 0, m_baseInertia[1], 0, + 0, 0, m_baseInertia[2]) + ); + + rot_from_world[0] = rot_from_parent[0]; + + // + for (int i = 0; i < num_links; ++i) { + const int parent = m_links[i].m_parent; + rot_from_parent[i+1] = btMatrix3x3(m_links[i].m_cachedRotParentToThis); + rot_from_world[i+1] = rot_from_parent[i+1] * rot_from_world[parent+1]; + + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + fromWorld.m_rotMat = rot_from_world[i+1]; + fromParent.transform(spatVel[parent+1], spatVel[i+1]); + + // now set vhat_i to its true value by doing + // vhat_i += qidot * shat_i + if(!m_useGlobalVelocities) + { + spatJointVel.setZero(); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + spatJointVel += m_links[i].m_axes[dof] * getJointVelMultiDof(i)[dof]; + + // remember vhat_i is really vhat_p(i) (but in current frame) at this point => we need to add velocity across the inboard joint + spatVel[i+1] += spatJointVel; + + // + // vhat_i is vhat_p(i) transformed to local coors + the velocity across the i-th inboard joint + //spatVel[i+1] = fromParent * spatVel[parent+1] + spatJointVel; + + } + else + { + fromWorld.transformRotationOnly(m_links[i].m_absFrameTotVelocity, spatVel[i+1]); + fromWorld.transformRotationOnly(m_links[i].m_absFrameLocVelocity, spatJointVel); + } + + // we can now calculate chat_i + spatVel[i+1].cross(spatJointVel, spatCoriolisAcc[i]); + + // calculate zhat_i^A + // + //external forces + btVector3 linkAppliedForce = isConstraintPass? m_links[i].m_appliedConstraintForce : m_links[i].m_appliedForce; + btVector3 linkAppliedTorque =isConstraintPass ? m_links[i].m_appliedConstraintTorque : m_links[i].m_appliedTorque; + + zeroAccSpatFrc[i+1].setVector(-(rot_from_world[i+1] * linkAppliedTorque), -(rot_from_world[i+1] * linkAppliedForce )); + +#if 0 + { + + b3Printf("stepVelocitiesMultiDof zeroAccSpatFrc[%d] linear:%f,%f,%f, angular:%f,%f,%f", + i+1, + zeroAccSpatFrc[i+1].m_topVec[0], + zeroAccSpatFrc[i+1].m_topVec[1], + zeroAccSpatFrc[i+1].m_topVec[2], + + zeroAccSpatFrc[i+1].m_bottomVec[0], + zeroAccSpatFrc[i+1].m_bottomVec[1], + zeroAccSpatFrc[i+1].m_bottomVec[2]); + } +#endif + // + //adding damping terms (only) + btScalar linDampMult = 1., angDampMult = 1.; + zeroAccSpatFrc[i+1].addVector(angDampMult * m_links[i].m_inertiaLocal * spatVel[i+1].getAngular() * (DAMPING_K1_ANGULAR + DAMPING_K2_ANGULAR * spatVel[i+1].getAngular().safeNorm()), + linDampMult * m_links[i].m_mass * spatVel[i+1].getLinear() * (DAMPING_K1_LINEAR + DAMPING_K2_LINEAR * spatVel[i+1].getLinear().safeNorm())); + + // calculate Ihat_i^A + //init the spatial AB inertia (it has the simple form thanks to choosing local body frames origins at their COMs) + spatInertia[i+1].setMatrix( btMatrix3x3(0,0,0,0,0,0,0,0,0), + // + btMatrix3x3(m_links[i].m_mass, 0, 0, + 0, m_links[i].m_mass, 0, + 0, 0, m_links[i].m_mass), + // + btMatrix3x3(m_links[i].m_inertiaLocal[0], 0, 0, + 0, m_links[i].m_inertiaLocal[1], 0, + 0, 0, m_links[i].m_inertiaLocal[2]) + ); + // + //p += vhat x Ihat vhat - done in a simpler way + if(m_useGyroTerm) + zeroAccSpatFrc[i+1].addAngular(spatVel[i+1].getAngular().cross(m_links[i].m_inertiaLocal * spatVel[i+1].getAngular())); + // + zeroAccSpatFrc[i+1].addLinear(m_links[i].m_mass * spatVel[i+1].getAngular().cross(spatVel[i+1].getLinear())); + //btVector3 temp = m_links[i].m_mass * spatVel[i+1].getAngular().cross(spatVel[i+1].getLinear()); + ////clamp parent's omega + //btScalar parOmegaMod = temp.length(); + //btScalar parOmegaModMax = 1000; + //if(parOmegaMod > parOmegaModMax) + // temp *= parOmegaModMax / parOmegaMod; + //zeroAccSpatFrc[i+1].addLinear(temp); + //printf("|zeroAccSpatFrc[%d]| = %.4f\n", i+1, temp.length()); + //temp = spatCoriolisAcc[i].getLinear(); + //printf("|spatCoriolisAcc[%d]| = %.4f\n", i+1, temp.length()); + + + + //printf("w[%d] = [%.4f %.4f %.4f]\n", i, vel_top_angular[i+1].x(), vel_top_angular[i+1].y(), vel_top_angular[i+1].z()); + //printf("v[%d] = [%.4f %.4f %.4f]\n", i, vel_bottom_linear[i+1].x(), vel_bottom_linear[i+1].y(), vel_bottom_linear[i+1].z()); + //printf("c[%d] = [%.4f %.4f %.4f]\n", i, coriolis_bottom_linear[i].x(), coriolis_bottom_linear[i].y(), coriolis_bottom_linear[i].z()); + } + + // 'Downward' loop. + // (part of TreeForwardDynamics in Mirtich.) + for (int i = num_links - 1; i >= 0; --i) + { + const int parent = m_links[i].m_parent; + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + hDof = spatInertia[i+1] * m_links[i].m_axes[dof]; + // + Y[m_links[i].m_dofOffset + dof] = m_links[i].m_jointTorque[dof] + - m_links[i].m_axes[dof].dot(zeroAccSpatFrc[i+1]) + - spatCoriolisAcc[i].dot(hDof) + ; + } + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + btScalar *D_row = &D[dof * m_links[i].m_dofCount]; + for(int dof2 = 0; dof2 < m_links[i].m_dofCount; ++dof2) + { + btSpatialForceVector &hDof2 = h[m_links[i].m_dofOffset + dof2]; + D_row[dof2] = m_links[i].m_axes[dof].dot(hDof2); + } + } + + btScalar *invDi = &invD[m_links[i].m_dofOffset*m_links[i].m_dofOffset]; + switch(m_links[i].m_jointType) + { + case btMultibodyLink::ePrismatic: + case btMultibodyLink::eRevolute: + { + invDi[0] = 1.0f / D[0]; + break; + } + case btMultibodyLink::eSpherical: + case btMultibodyLink::ePlanar: + { + btMatrix3x3 D3x3; D3x3.setValue(D[0], D[1], D[2], D[3], D[4], D[5], D[6], D[7], D[8]); + btMatrix3x3 invD3x3; invD3x3 = D3x3.inverse(); + + //unroll the loop? + for(int row = 0; row < 3; ++row) + { + for(int col = 0; col < 3; ++col) + { + invDi[row * 3 + col] = invD3x3[row][col]; + } + } + + break; + } + default: + { + + } + } + + //determine h*D^{-1} + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + spatForceVecTemps[dof].setZero(); + + for(int dof2 = 0; dof2 < m_links[i].m_dofCount; ++dof2) + { + btSpatialForceVector &hDof2 = h[m_links[i].m_dofOffset + dof2]; + // + spatForceVecTemps[dof] += hDof2 * invDi[dof2 * m_links[i].m_dofCount + dof]; + } + } + + dyadTemp = spatInertia[i+1]; + + //determine (h*D^{-1}) * h^{T} + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + dyadTemp -= symmetricSpatialOuterProduct(hDof, spatForceVecTemps[dof]); + } + + fromParent.transformInverse(dyadTemp, spatInertia[parent+1], btSpatialTransformationMatrix::Add); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + invD_times_Y[dof] = 0.f; + + for(int dof2 = 0; dof2 < m_links[i].m_dofCount; ++dof2) + { + invD_times_Y[dof] += invDi[dof * m_links[i].m_dofCount + dof2] * Y[m_links[i].m_dofOffset + dof2]; + } + } + + spatForceVecTemps[0] = zeroAccSpatFrc[i+1] + spatInertia[i+1] * spatCoriolisAcc[i]; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + spatForceVecTemps[0] += hDof * invD_times_Y[dof]; + } + + fromParent.transformInverse(spatForceVecTemps[0], spatForceVecTemps[1]); + + zeroAccSpatFrc[parent+1] += spatForceVecTemps[1]; + } + + + // Second 'upward' loop + // (part of TreeForwardDynamics in Mirtich) + + if (m_fixedBase) + { + spatAcc[0].setZero(); + } + else + { + if (num_links > 0) + { + m_cachedInertiaValid = true; + m_cachedInertiaTopLeft = spatInertia[0].m_topLeftMat; + m_cachedInertiaTopRight = spatInertia[0].m_topRightMat; + m_cachedInertiaLowerLeft = spatInertia[0].m_bottomLeftMat; + m_cachedInertiaLowerRight= spatInertia[0].m_topLeftMat.transpose(); + + } + + solveImatrix(zeroAccSpatFrc[0], result); + spatAcc[0] = -result; + } + + + // now do the loop over the m_links + for (int i = 0; i < num_links; ++i) + { + // qdd = D^{-1} * (Y - h^{T}*apar) = (S^{T}*I*S)^{-1} * (tau - S^{T}*I*cor - S^{T}*zeroAccFrc - S^{T}*I*apar) + // a = apar + cor + Sqdd + //or + // qdd = D^{-1} * (Y - h^{T}*(apar+cor)) + // a = apar + Sqdd + + const int parent = m_links[i].m_parent; + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + + fromParent.transform(spatAcc[parent+1], spatAcc[i+1]); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + Y_minus_hT_a[dof] = Y[m_links[i].m_dofOffset + dof] - spatAcc[i+1].dot(hDof); + } + + btScalar *invDi = &invD[m_links[i].m_dofOffset*m_links[i].m_dofOffset]; + //D^{-1} * (Y - h^{T}*apar) + mulMatrix(invDi, Y_minus_hT_a, m_links[i].m_dofCount, m_links[i].m_dofCount, m_links[i].m_dofCount, 1, &joint_accel[m_links[i].m_dofOffset]); + + spatAcc[i+1] += spatCoriolisAcc[i]; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + spatAcc[i+1] += m_links[i].m_axes[dof] * joint_accel[m_links[i].m_dofOffset + dof]; + + if (m_links[i].m_jointFeedback) + { + m_internalNeedsJointFeedback = true; + + btVector3 angularBotVec = (spatInertia[i+1]*spatAcc[i+1]+zeroAccSpatFrc[i+1]).m_bottomVec; + btVector3 linearTopVec = (spatInertia[i+1]*spatAcc[i+1]+zeroAccSpatFrc[i+1]).m_topVec; + + if (gJointFeedbackInJointFrame) + { + //shift the reaction forces to the joint frame + //linear (force) component is the same + //shift the angular (torque, moment) component using the relative position, m_links[i].m_dVector + angularBotVec = angularBotVec - linearTopVec.cross(m_links[i].m_dVector); + } + + + if (gJointFeedbackInWorldSpace) + { + if (isConstraintPass) + { + m_links[i].m_jointFeedback->m_reactionForces.m_bottomVec += m_links[i].m_cachedWorldTransform.getBasis()*angularBotVec; + m_links[i].m_jointFeedback->m_reactionForces.m_topVec += m_links[i].m_cachedWorldTransform.getBasis()*linearTopVec; + } else + { + m_links[i].m_jointFeedback->m_reactionForces.m_bottomVec = m_links[i].m_cachedWorldTransform.getBasis()*angularBotVec; + m_links[i].m_jointFeedback->m_reactionForces.m_topVec = m_links[i].m_cachedWorldTransform.getBasis()*linearTopVec; + } + } else + { + if (isConstraintPass) + { + m_links[i].m_jointFeedback->m_reactionForces.m_bottomVec += angularBotVec; + m_links[i].m_jointFeedback->m_reactionForces.m_topVec += linearTopVec; + + } + else + { + m_links[i].m_jointFeedback->m_reactionForces.m_bottomVec = angularBotVec; + m_links[i].m_jointFeedback->m_reactionForces.m_topVec = linearTopVec; + } + } + } + + } + + // transform base accelerations back to the world frame. + btVector3 omegadot_out = rot_from_parent[0].transpose() * spatAcc[0].getAngular(); + output[0] = omegadot_out[0]; + output[1] = omegadot_out[1]; + output[2] = omegadot_out[2]; + + btVector3 vdot_out = rot_from_parent[0].transpose() * (spatAcc[0].getLinear() + spatVel[0].getAngular().cross(spatVel[0].getLinear())); + output[3] = vdot_out[0]; + output[4] = vdot_out[1]; + output[5] = vdot_out[2]; + + ///////////////// + //printf("q = ["); + //printf("%.6f, %.6f, %.6f, %.6f, %.6f, %.6f, %.6f ", m_baseQuat.x(), m_baseQuat.y(), m_baseQuat.z(), m_baseQuat.w(), m_basePos.x(), m_basePos.y(), m_basePos.z()); + //for(int link = 0; link < getNumLinks(); ++link) + // for(int dof = 0; dof < m_links[link].m_dofCount; ++dof) + // printf("%.6f ", m_links[link].m_jointPos[dof]); + //printf("]\n"); + //// + //printf("qd = ["); + //for(int dof = 0; dof < getNumDofs() + 6; ++dof) + // printf("%.6f ", m_realBuf[dof]); + //printf("]\n"); + //printf("qdd = ["); + //for(int dof = 0; dof < getNumDofs() + 6; ++dof) + // printf("%.6f ", output[dof]); + //printf("]\n"); + ///////////////// + + // Final step: add the accelerations (times dt) to the velocities. + + if (!isConstraintPass) + { + if(dt > 0.) + applyDeltaVeeMultiDof(output, dt); + + } + ///// + //btScalar angularThres = 1; + //btScalar maxAngVel = 0.; + //bool scaleDown = 1.; + //for(int link = 0; link < m_links.size(); ++link) + //{ + // if(spatVel[link+1].getAngular().length() > maxAngVel) + // { + // maxAngVel = spatVel[link+1].getAngular().length(); + // scaleDown = angularThres / spatVel[link+1].getAngular().length(); + // break; + // } + //} + + //if(scaleDown != 1.) + //{ + // for(int link = 0; link < m_links.size(); ++link) + // { + // if(m_links[link].m_jointType == btMultibodyLink::eRevolute || m_links[link].m_jointType == btMultibodyLink::eSpherical) + // { + // for(int dof = 0; dof < m_links[link].m_dofCount; ++dof) + // getJointVelMultiDof(link)[dof] *= scaleDown; + // } + // } + //} + ///// + + ///////////////////// + if(m_useGlobalVelocities) + { + for (int i = 0; i < num_links; ++i) + { + const int parent = m_links[i].m_parent; + //rot_from_parent[i+1] = btMatrix3x3(m_links[i].m_cachedRotParentToThis); /// <- done + //rot_from_world[i+1] = rot_from_parent[i+1] * rot_from_world[parent+1]; /// <- done + + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + fromWorld.m_rotMat = rot_from_world[i+1]; + + // vhat_i = i_xhat_p(i) * vhat_p(i) + fromParent.transform(spatVel[parent+1], spatVel[i+1]); + //nice alternative below (using operator *) but it generates temps + ///////////////////////////////////////////////////////////// + + // now set vhat_i to its true value by doing + // vhat_i += qidot * shat_i + spatJointVel.setZero(); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + spatJointVel += m_links[i].m_axes[dof] * getJointVelMultiDof(i)[dof]; + + // remember vhat_i is really vhat_p(i) (but in current frame) at this point => we need to add velocity across the inboard joint + spatVel[i+1] += spatJointVel; + + + fromWorld.transformInverseRotationOnly(spatVel[i+1], m_links[i].m_absFrameTotVelocity); + fromWorld.transformInverseRotationOnly(spatJointVel, m_links[i].m_absFrameLocVelocity); + } + } + +} + + + +void btMultiBody::solveImatrix(const btVector3& rhs_top, const btVector3& rhs_bot, btScalar result[6]) const +{ + int num_links = getNumLinks(); + ///solve I * x = rhs, so the result = invI * rhs + if (num_links == 0) + { + // in the case of 0 m_links (i.e. a plain rigid body, not a multibody) rhs * invI is easier + result[0] = rhs_bot[0] / m_baseInertia[0]; + result[1] = rhs_bot[1] / m_baseInertia[1]; + result[2] = rhs_bot[2] / m_baseInertia[2]; + result[3] = rhs_top[0] / m_baseMass; + result[4] = rhs_top[1] / m_baseMass; + result[5] = rhs_top[2] / m_baseMass; + } else + { + if (!m_cachedInertiaValid) + { + for (int i=0;i<6;i++) + { + result[i] = 0.f; + } + return; + } + /// Special routine for calculating the inverse of a spatial inertia matrix + ///the 6x6 matrix is stored as 4 blocks of 3x3 matrices + btMatrix3x3 Binv = m_cachedInertiaTopRight.inverse()*-1.f; + btMatrix3x3 tmp = m_cachedInertiaLowerRight * Binv; + btMatrix3x3 invIupper_right = (tmp * m_cachedInertiaTopLeft + m_cachedInertiaLowerLeft).inverse(); + tmp = invIupper_right * m_cachedInertiaLowerRight; + btMatrix3x3 invI_upper_left = (tmp * Binv); + btMatrix3x3 invI_lower_right = (invI_upper_left).transpose(); + tmp = m_cachedInertiaTopLeft * invI_upper_left; + tmp[0][0]-= 1.0; + tmp[1][1]-= 1.0; + tmp[2][2]-= 1.0; + btMatrix3x3 invI_lower_left = (Binv * tmp); + + //multiply result = invI * rhs + { + btVector3 vtop = invI_upper_left*rhs_top; + btVector3 tmp; + tmp = invIupper_right * rhs_bot; + vtop += tmp; + btVector3 vbot = invI_lower_left*rhs_top; + tmp = invI_lower_right * rhs_bot; + vbot += tmp; + result[0] = vtop[0]; + result[1] = vtop[1]; + result[2] = vtop[2]; + result[3] = vbot[0]; + result[4] = vbot[1]; + result[5] = vbot[2]; + } + + } +} +void btMultiBody::solveImatrix(const btSpatialForceVector &rhs, btSpatialMotionVector &result) const +{ + int num_links = getNumLinks(); + ///solve I * x = rhs, so the result = invI * rhs + if (num_links == 0) + { + // in the case of 0 m_links (i.e. a plain rigid body, not a multibody) rhs * invI is easier + result.setAngular(rhs.getAngular() / m_baseInertia); + result.setLinear(rhs.getLinear() / m_baseMass); + } else + { + /// Special routine for calculating the inverse of a spatial inertia matrix + ///the 6x6 matrix is stored as 4 blocks of 3x3 matrices + if (!m_cachedInertiaValid) + { + result.setLinear(btVector3(0,0,0)); + result.setAngular(btVector3(0,0,0)); + result.setVector(btVector3(0,0,0),btVector3(0,0,0)); + return; + } + btMatrix3x3 Binv = m_cachedInertiaTopRight.inverse()*-1.f; + btMatrix3x3 tmp = m_cachedInertiaLowerRight * Binv; + btMatrix3x3 invIupper_right = (tmp * m_cachedInertiaTopLeft + m_cachedInertiaLowerLeft).inverse(); + tmp = invIupper_right * m_cachedInertiaLowerRight; + btMatrix3x3 invI_upper_left = (tmp * Binv); + btMatrix3x3 invI_lower_right = (invI_upper_left).transpose(); + tmp = m_cachedInertiaTopLeft * invI_upper_left; + tmp[0][0]-= 1.0; + tmp[1][1]-= 1.0; + tmp[2][2]-= 1.0; + btMatrix3x3 invI_lower_left = (Binv * tmp); + + //multiply result = invI * rhs + { + btVector3 vtop = invI_upper_left*rhs.getLinear(); + btVector3 tmp; + tmp = invIupper_right * rhs.getAngular(); + vtop += tmp; + btVector3 vbot = invI_lower_left*rhs.getLinear(); + tmp = invI_lower_right * rhs.getAngular(); + vbot += tmp; + result.setVector(vtop, vbot); + } + + } +} + +void btMultiBody::mulMatrix(btScalar *pA, btScalar *pB, int rowsA, int colsA, int rowsB, int colsB, btScalar *pC) const +{ + for (int row = 0; row < rowsA; row++) + { + for (int col = 0; col < colsB; col++) + { + pC[row * colsB + col] = 0.f; + for (int inner = 0; inner < rowsB; inner++) + { + pC[row * colsB + col] += pA[row * colsA + inner] * pB[col + inner * colsB]; + } + } + } +} + +void btMultiBody::calcAccelerationDeltasMultiDof(const btScalar *force, btScalar *output, + btAlignedObjectArray<btScalar> &scratch_r, btAlignedObjectArray<btVector3> &scratch_v) const +{ + // Temporary matrices/vectors -- use scratch space from caller + // so that we don't have to keep reallocating every frame + + + int num_links = getNumLinks(); + scratch_r.resize(m_dofCount); + scratch_v.resize(4*num_links + 4); + + btScalar * r_ptr = m_dofCount ? &scratch_r[0] : 0; + btVector3 * v_ptr = &scratch_v[0]; + + // zhat_i^A (scratch space) + btSpatialForceVector * zeroAccSpatFrc = (btSpatialForceVector *)v_ptr; + v_ptr += num_links * 2 + 2; + + // rot_from_parent (cached from calcAccelerations) + const btMatrix3x3 * rot_from_parent = &m_matrixBuf[0]; + + // hhat (cached), accel (scratch) + // hhat is NOT stored for the base (but ahat is) + const btSpatialForceVector * h = (btSpatialForceVector *)(m_dofCount > 0 ? &m_vectorBuf[0] : 0); + btSpatialMotionVector * spatAcc = (btSpatialMotionVector *)v_ptr; + v_ptr += num_links * 2 + 2; + + // Y_i (scratch), invD_i (cached) + const btScalar * invD = m_dofCount > 0 ? &m_realBuf[6 + m_dofCount] : 0; + btScalar * Y = r_ptr; + //////////////// + //aux variables + btScalar invD_times_Y[6]; //D^{-1} * Y [dofxdof x dofx1 = dofx1] <=> D^{-1} * u; better moved to buffers since it is recalced in calcAccelerationDeltasMultiDof; num_dof of btScalar would cover all bodies + btSpatialMotionVector result; //holds results of the SolveImatrix op; it is a spatial motion vector (accel) + btScalar Y_minus_hT_a[6]; //Y - h^{T} * a; it's dofx1 for each body so a single 6x1 temp is enough + btSpatialForceVector spatForceVecTemps[6]; //6 temporary spatial force vectors + btSpatialTransformationMatrix fromParent; + ///////////////// + + // First 'upward' loop. + // Combines CompTreeLinkVelocities and InitTreeLinks from Mirtich. + + // Fill in zero_acc + // -- set to force/torque on the base, zero otherwise + if (m_fixedBase) + { + zeroAccSpatFrc[0].setZero(); + } else + { + //test forces + fromParent.m_rotMat = rot_from_parent[0]; + fromParent.transformRotationOnly(btSpatialForceVector(-force[0],-force[1],-force[2], -force[3],-force[4],-force[5]), zeroAccSpatFrc[0]); + } + for (int i = 0; i < num_links; ++i) + { + zeroAccSpatFrc[i+1].setZero(); + } + + // 'Downward' loop. + // (part of TreeForwardDynamics in Mirtich.) + for (int i = num_links - 1; i >= 0; --i) + { + const int parent = m_links[i].m_parent; + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + Y[m_links[i].m_dofOffset + dof] = force[6 + m_links[i].m_dofOffset + dof] + - m_links[i].m_axes[dof].dot(zeroAccSpatFrc[i+1]) + ; + } + + btVector3 in_top, in_bottom, out_top, out_bottom; + const btScalar *invDi = &invD[m_links[i].m_dofOffset*m_links[i].m_dofOffset]; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + invD_times_Y[dof] = 0.f; + + for(int dof2 = 0; dof2 < m_links[i].m_dofCount; ++dof2) + { + invD_times_Y[dof] += invDi[dof * m_links[i].m_dofCount + dof2] * Y[m_links[i].m_dofOffset + dof2]; + } + } + + // Zp += pXi * (Zi + hi*Yi/Di) + spatForceVecTemps[0] = zeroAccSpatFrc[i+1]; + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + const btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + spatForceVecTemps[0] += hDof * invD_times_Y[dof]; + } + + + fromParent.transformInverse(spatForceVecTemps[0], spatForceVecTemps[1]); + + zeroAccSpatFrc[parent+1] += spatForceVecTemps[1]; + } + + // ptr to the joint accel part of the output + btScalar * joint_accel = output + 6; + + + // Second 'upward' loop + // (part of TreeForwardDynamics in Mirtich) + + if (m_fixedBase) + { + spatAcc[0].setZero(); + } + else + { + solveImatrix(zeroAccSpatFrc[0], result); + spatAcc[0] = -result; + + } + + // now do the loop over the m_links + for (int i = 0; i < num_links; ++i) + { + const int parent = m_links[i].m_parent; + fromParent.m_rotMat = rot_from_parent[i+1]; fromParent.m_trnVec = m_links[i].m_cachedRVector; + + fromParent.transform(spatAcc[parent+1], spatAcc[i+1]); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + { + const btSpatialForceVector &hDof = h[m_links[i].m_dofOffset + dof]; + // + Y_minus_hT_a[dof] = Y[m_links[i].m_dofOffset + dof] - spatAcc[i+1].dot(hDof); + } + + const btScalar *invDi = &invD[m_links[i].m_dofOffset*m_links[i].m_dofOffset]; + mulMatrix(const_cast<btScalar*>(invDi), Y_minus_hT_a, m_links[i].m_dofCount, m_links[i].m_dofCount, m_links[i].m_dofCount, 1, &joint_accel[m_links[i].m_dofOffset]); + + for(int dof = 0; dof < m_links[i].m_dofCount; ++dof) + spatAcc[i+1] += m_links[i].m_axes[dof] * joint_accel[m_links[i].m_dofOffset + dof]; + } + + // transform base accelerations back to the world frame. + btVector3 omegadot_out; + omegadot_out = rot_from_parent[0].transpose() * spatAcc[0].getAngular(); + output[0] = omegadot_out[0]; + output[1] = omegadot_out[1]; + output[2] = omegadot_out[2]; + + btVector3 vdot_out; + vdot_out = rot_from_parent[0].transpose() * spatAcc[0].getLinear(); + output[3] = vdot_out[0]; + output[4] = vdot_out[1]; + output[5] = vdot_out[2]; + + ///////////////// + //printf("delta = ["); + //for(int dof = 0; dof < getNumDofs() + 6; ++dof) + // printf("%.2f ", output[dof]); + //printf("]\n"); + ///////////////// +} + + + + +void btMultiBody::stepPositionsMultiDof(btScalar dt, btScalar *pq, btScalar *pqd) +{ + int num_links = getNumLinks(); + // step position by adding dt * velocity + //btVector3 v = getBaseVel(); + //m_basePos += dt * v; + // + btScalar *pBasePos = (pq ? &pq[4] : m_basePos); + btScalar *pBaseVel = (pqd ? &pqd[3] : &m_realBuf[3]); //note: the !pqd case assumes m_realBuf holds with base velocity at 3,4,5 (should be wrapped for safety) + // + pBasePos[0] += dt * pBaseVel[0]; + pBasePos[1] += dt * pBaseVel[1]; + pBasePos[2] += dt * pBaseVel[2]; + + /////////////////////////////// + //local functor for quaternion integration (to avoid error prone redundancy) + struct + { + //"exponential map" based on btTransformUtil::integrateTransform(..) + void operator() (const btVector3 &omega, btQuaternion &quat, bool baseBody, btScalar dt) + { + //baseBody => quat is alias and omega is global coor + //!baseBody => quat is alibi and omega is local coor + + btVector3 axis; + btVector3 angvel; + + if(!baseBody) + angvel = quatRotate(quat, omega); //if quat is not m_baseQuat, it is alibi => ok + else + angvel = omega; + + btScalar fAngle = angvel.length(); + //limit the angular motion + if (fAngle * dt > ANGULAR_MOTION_THRESHOLD) + { + fAngle = btScalar(0.5)*SIMD_HALF_PI / dt; + } + + if ( fAngle < btScalar(0.001) ) + { + // use Taylor's expansions of sync function + axis = angvel*( btScalar(0.5)*dt-(dt*dt*dt)*(btScalar(0.020833333333))*fAngle*fAngle ); + } + else + { + // sync(fAngle) = sin(c*fAngle)/t + axis = angvel*( btSin(btScalar(0.5)*fAngle*dt)/fAngle ); + } + + if(!baseBody) + quat = btQuaternion(axis.x(),axis.y(),axis.z(),btCos( fAngle*dt*btScalar(0.5) )) * quat; + else + quat = quat * btQuaternion(-axis.x(),-axis.y(),-axis.z(),btCos( fAngle*dt*btScalar(0.5) )); + //equivalent to: quat = (btQuaternion(axis.x(),axis.y(),axis.z(),btCos( fAngle*dt*btScalar(0.5) )) * quat.inverse()).inverse(); + + quat.normalize(); + } + } pQuatUpdateFun; + /////////////////////////////// + + //pQuatUpdateFun(getBaseOmega(), m_baseQuat, true, dt); + // + btScalar *pBaseQuat = pq ? pq : m_baseQuat; + btScalar *pBaseOmega = pqd ? pqd : &m_realBuf[0]; //note: the !pqd case assumes m_realBuf starts with base omega (should be wrapped for safety) + // + btQuaternion baseQuat; baseQuat.setValue(pBaseQuat[0], pBaseQuat[1], pBaseQuat[2], pBaseQuat[3]); + btVector3 baseOmega; baseOmega.setValue(pBaseOmega[0], pBaseOmega[1], pBaseOmega[2]); + pQuatUpdateFun(baseOmega, baseQuat, true, dt); + pBaseQuat[0] = baseQuat.x(); + pBaseQuat[1] = baseQuat.y(); + pBaseQuat[2] = baseQuat.z(); + pBaseQuat[3] = baseQuat.w(); + + + //printf("pBaseOmega = %.4f %.4f %.4f\n", pBaseOmega->x(), pBaseOmega->y(), pBaseOmega->z()); + //printf("pBaseVel = %.4f %.4f %.4f\n", pBaseVel->x(), pBaseVel->y(), pBaseVel->z()); + //printf("baseQuat = %.4f %.4f %.4f %.4f\n", pBaseQuat->x(), pBaseQuat->y(), pBaseQuat->z(), pBaseQuat->w()); + + if(pq) + pq += 7; + if(pqd) + pqd += 6; + + // Finally we can update m_jointPos for each of the m_links + for (int i = 0; i < num_links; ++i) + { + btScalar *pJointPos = (pq ? pq : &m_links[i].m_jointPos[0]); + btScalar *pJointVel = (pqd ? pqd : getJointVelMultiDof(i)); + + switch(m_links[i].m_jointType) + { + case btMultibodyLink::ePrismatic: + case btMultibodyLink::eRevolute: + { + btScalar jointVel = pJointVel[0]; + pJointPos[0] += dt * jointVel; + break; + } + case btMultibodyLink::eSpherical: + { + btVector3 jointVel; jointVel.setValue(pJointVel[0], pJointVel[1], pJointVel[2]); + btQuaternion jointOri; jointOri.setValue(pJointPos[0], pJointPos[1], pJointPos[2], pJointPos[3]); + pQuatUpdateFun(jointVel, jointOri, false, dt); + pJointPos[0] = jointOri.x(); pJointPos[1] = jointOri.y(); pJointPos[2] = jointOri.z(); pJointPos[3] = jointOri.w(); + break; + } + case btMultibodyLink::ePlanar: + { + pJointPos[0] += dt * getJointVelMultiDof(i)[0]; + + btVector3 q0_coors_qd1qd2 = getJointVelMultiDof(i)[1] * m_links[i].getAxisBottom(1) + getJointVelMultiDof(i)[2] * m_links[i].getAxisBottom(2); + btVector3 no_q0_coors_qd1qd2 = quatRotate(btQuaternion(m_links[i].getAxisTop(0), pJointPos[0]), q0_coors_qd1qd2); + pJointPos[1] += m_links[i].getAxisBottom(1).dot(no_q0_coors_qd1qd2) * dt; + pJointPos[2] += m_links[i].getAxisBottom(2).dot(no_q0_coors_qd1qd2) * dt; + + break; + } + default: + { + } + + } + + m_links[i].updateCacheMultiDof(pq); + + if(pq) + pq += m_links[i].m_posVarCount; + if(pqd) + pqd += m_links[i].m_dofCount; + } +} + +void btMultiBody::fillConstraintJacobianMultiDof(int link, + const btVector3 &contact_point, + const btVector3 &normal_ang, + const btVector3 &normal_lin, + btScalar *jac, + btAlignedObjectArray<btScalar> &scratch_r, + btAlignedObjectArray<btVector3> &scratch_v, + btAlignedObjectArray<btMatrix3x3> &scratch_m) const +{ + // temporary space + int num_links = getNumLinks(); + int m_dofCount = getNumDofs(); + scratch_v.resize(3*num_links + 3); //(num_links + base) offsets + (num_links + base) normals_lin + (num_links + base) normals_ang + scratch_m.resize(num_links + 1); + + btVector3 * v_ptr = &scratch_v[0]; + btVector3 * p_minus_com_local = v_ptr; v_ptr += num_links + 1; + btVector3 * n_local_lin = v_ptr; v_ptr += num_links + 1; + btVector3 * n_local_ang = v_ptr; v_ptr += num_links + 1; + btAssert(v_ptr - &scratch_v[0] == scratch_v.size()); + + scratch_r.resize(m_dofCount); + btScalar * results = m_dofCount > 0 ? &scratch_r[0] : 0; + + btMatrix3x3 * rot_from_world = &scratch_m[0]; + + const btVector3 p_minus_com_world = contact_point - m_basePos; + const btVector3 &normal_lin_world = normal_lin; //convenience + const btVector3 &normal_ang_world = normal_ang; + + rot_from_world[0] = btMatrix3x3(m_baseQuat); + + // omega coeffients first. + btVector3 omega_coeffs_world; + omega_coeffs_world = p_minus_com_world.cross(normal_lin_world); + jac[0] = omega_coeffs_world[0] + normal_ang_world[0]; + jac[1] = omega_coeffs_world[1] + normal_ang_world[1]; + jac[2] = omega_coeffs_world[2] + normal_ang_world[2]; + // then v coefficients + jac[3] = normal_lin_world[0]; + jac[4] = normal_lin_world[1]; + jac[5] = normal_lin_world[2]; + + //create link-local versions of p_minus_com and normal + p_minus_com_local[0] = rot_from_world[0] * p_minus_com_world; + n_local_lin[0] = rot_from_world[0] * normal_lin_world; + n_local_ang[0] = rot_from_world[0] * normal_ang_world; + + // Set remaining jac values to zero for now. + for (int i = 6; i < 6 + m_dofCount; ++i) + { + jac[i] = 0; + } + + // Qdot coefficients, if necessary. + if (num_links > 0 && link > -1) { + + // TODO: speed this up -- don't calculate for m_links we don't need. + // (Also, we are making 3 separate calls to this function, for the normal & the 2 friction directions, + // which is resulting in repeated work being done...) + + // calculate required normals & positions in the local frames. + for (int i = 0; i < num_links; ++i) { + + // transform to local frame + const int parent = m_links[i].m_parent; + const btMatrix3x3 mtx(m_links[i].m_cachedRotParentToThis); + rot_from_world[i+1] = mtx * rot_from_world[parent+1]; + + n_local_lin[i+1] = mtx * n_local_lin[parent+1]; + n_local_ang[i+1] = mtx * n_local_ang[parent+1]; + p_minus_com_local[i+1] = mtx * p_minus_com_local[parent+1] - m_links[i].m_cachedRVector; + + // calculate the jacobian entry + switch(m_links[i].m_jointType) + { + case btMultibodyLink::eRevolute: + { + results[m_links[i].m_dofOffset] = n_local_lin[i+1].dot(m_links[i].getAxisTop(0).cross(p_minus_com_local[i+1]) + m_links[i].getAxisBottom(0)); + results[m_links[i].m_dofOffset] += n_local_ang[i+1].dot(m_links[i].getAxisTop(0)); + break; + } + case btMultibodyLink::ePrismatic: + { + results[m_links[i].m_dofOffset] = n_local_lin[i+1].dot(m_links[i].getAxisBottom(0)); + break; + } + case btMultibodyLink::eSpherical: + { + results[m_links[i].m_dofOffset + 0] = n_local_lin[i+1].dot(m_links[i].getAxisTop(0).cross(p_minus_com_local[i+1]) + m_links[i].getAxisBottom(0)); + results[m_links[i].m_dofOffset + 1] = n_local_lin[i+1].dot(m_links[i].getAxisTop(1).cross(p_minus_com_local[i+1]) + m_links[i].getAxisBottom(1)); + results[m_links[i].m_dofOffset + 2] = n_local_lin[i+1].dot(m_links[i].getAxisTop(2).cross(p_minus_com_local[i+1]) + m_links[i].getAxisBottom(2)); + + results[m_links[i].m_dofOffset + 0] += n_local_ang[i+1].dot(m_links[i].getAxisTop(0)); + results[m_links[i].m_dofOffset + 1] += n_local_ang[i+1].dot(m_links[i].getAxisTop(1)); + results[m_links[i].m_dofOffset + 2] += n_local_ang[i+1].dot(m_links[i].getAxisTop(2)); + + break; + } + case btMultibodyLink::ePlanar: + { + results[m_links[i].m_dofOffset + 0] = n_local_lin[i+1].dot(m_links[i].getAxisTop(0).cross(p_minus_com_local[i+1]));// + m_links[i].getAxisBottom(0)); + results[m_links[i].m_dofOffset + 1] = n_local_lin[i+1].dot(m_links[i].getAxisBottom(1)); + results[m_links[i].m_dofOffset + 2] = n_local_lin[i+1].dot(m_links[i].getAxisBottom(2)); + + break; + } + default: + { + } + } + + } + + // Now copy through to output. + //printf("jac[%d] = ", link); + while (link != -1) + { + for(int dof = 0; dof < m_links[link].m_dofCount; ++dof) + { + jac[6 + m_links[link].m_dofOffset + dof] = results[m_links[link].m_dofOffset + dof]; + //printf("%.2f\t", jac[6 + m_links[link].m_dofOffset + dof]); + } + + link = m_links[link].m_parent; + } + //printf("]\n"); + } +} + + +void btMultiBody::wakeUp() +{ + m_awake = true; +} + +void btMultiBody::goToSleep() +{ + m_awake = false; +} + +void btMultiBody::checkMotionAndSleepIfRequired(btScalar timestep) +{ + extern bool gDisableDeactivation; + if (!m_canSleep || gDisableDeactivation) + { + m_awake = true; + m_sleepTimer = 0; + return; + } + + // motion is computed as omega^2 + v^2 + (sum of squares of joint velocities) + btScalar motion = 0; + { + for (int i = 0; i < 6 + m_dofCount; ++i) + motion += m_realBuf[i] * m_realBuf[i]; + } + + + if (motion < SLEEP_EPSILON) { + m_sleepTimer += timestep; + if (m_sleepTimer > SLEEP_TIMEOUT) { + goToSleep(); + } + } else { + m_sleepTimer = 0; + if (!m_awake) + wakeUp(); + } +} + + +void btMultiBody::forwardKinematics(btAlignedObjectArray<btQuaternion>& world_to_local,btAlignedObjectArray<btVector3>& local_origin) +{ + + int num_links = getNumLinks(); + + // Cached 3x3 rotation matrices from parent frame to this frame. + btMatrix3x3* rot_from_parent =(btMatrix3x3 *) &m_matrixBuf[0]; + + rot_from_parent[0] = btMatrix3x3(m_baseQuat); //m_baseQuat assumed to be alias!? + + for (int i = 0; i < num_links; ++i) + { + rot_from_parent[i+1] = btMatrix3x3(m_links[i].m_cachedRotParentToThis); + } + + int nLinks = getNumLinks(); + ///base + num m_links + world_to_local.resize(nLinks+1); + local_origin.resize(nLinks+1); + + world_to_local[0] = getWorldToBaseRot(); + local_origin[0] = getBasePos(); + + for (int k=0;k<getNumLinks();k++) + { + const int parent = getParent(k); + world_to_local[k+1] = getParentToLocalRot(k) * world_to_local[parent+1]; + local_origin[k+1] = local_origin[parent+1] + (quatRotate(world_to_local[k+1].inverse() , getRVector(k))); + } + + for (int link=0;link<getNumLinks();link++) + { + int index = link+1; + + btVector3 posr = local_origin[index]; + btScalar quat[4]={-world_to_local[index].x(),-world_to_local[index].y(),-world_to_local[index].z(),world_to_local[index].w()}; + btTransform tr; + tr.setIdentity(); + tr.setOrigin(posr); + tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3])); + getLink(link).m_cachedWorldTransform = tr; + + } + +} + +void btMultiBody::updateCollisionObjectWorldTransforms(btAlignedObjectArray<btQuaternion>& world_to_local,btAlignedObjectArray<btVector3>& local_origin) +{ + world_to_local.resize(getNumLinks()+1); + local_origin.resize(getNumLinks()+1); + + world_to_local[0] = getWorldToBaseRot(); + local_origin[0] = getBasePos(); + + if (getBaseCollider()) + { + btVector3 posr = local_origin[0]; + // float pos[4]={posr.x(),posr.y(),posr.z(),1}; + btScalar quat[4]={-world_to_local[0].x(),-world_to_local[0].y(),-world_to_local[0].z(),world_to_local[0].w()}; + btTransform tr; + tr.setIdentity(); + tr.setOrigin(posr); + tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3])); + + getBaseCollider()->setWorldTransform(tr); + + } + + for (int k=0;k<getNumLinks();k++) + { + const int parent = getParent(k); + world_to_local[k+1] = getParentToLocalRot(k) * world_to_local[parent+1]; + local_origin[k+1] = local_origin[parent+1] + (quatRotate(world_to_local[k+1].inverse() , getRVector(k))); + } + + + for (int m=0;m<getNumLinks();m++) + { + btMultiBodyLinkCollider* col = getLink(m).m_collider; + if (col) + { + int link = col->m_link; + btAssert(link == m); + + int index = link+1; + + btVector3 posr = local_origin[index]; + // float pos[4]={posr.x(),posr.y(),posr.z(),1}; + btScalar quat[4]={-world_to_local[index].x(),-world_to_local[index].y(),-world_to_local[index].z(),world_to_local[index].w()}; + btTransform tr; + tr.setIdentity(); + tr.setOrigin(posr); + tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3])); + + col->setWorldTransform(tr); + } + } +} + +int btMultiBody::calculateSerializeBufferSize() const +{ + int sz = sizeof(btMultiBodyData); + return sz; +} + + ///fills the dataBuffer and returns the struct name (and 0 on failure) +const char* btMultiBody::serialize(void* dataBuffer, class btSerializer* serializer) const +{ + btMultiBodyData* mbd = (btMultiBodyData*) dataBuffer; + getBaseWorldTransform().serialize(mbd->m_baseWorldTransform); + mbd->m_baseMass = this->getBaseMass(); + getBaseInertia().serialize(mbd->m_baseInertia); + { + char* name = (char*) serializer->findNameForPointer(m_baseName); + mbd->m_baseName = (char*)serializer->getUniquePointer(name); + if (mbd->m_baseName) + { + serializer->serializeName(name); + } + } + mbd->m_numLinks = this->getNumLinks(); + if (mbd->m_numLinks) + { + int sz = sizeof(btMultiBodyLinkData); + int numElem = mbd->m_numLinks; + btChunk* chunk = serializer->allocate(sz,numElem); + btMultiBodyLinkData* memPtr = (btMultiBodyLinkData*)chunk->m_oldPtr; + for (int i=0;i<numElem;i++,memPtr++) + { + + memPtr->m_jointType = getLink(i).m_jointType; + memPtr->m_dofCount = getLink(i).m_dofCount; + memPtr->m_posVarCount = getLink(i).m_posVarCount; + + getLink(i).m_inertiaLocal.serialize(memPtr->m_linkInertia); + memPtr->m_linkMass = getLink(i).m_mass; + memPtr->m_parentIndex = getLink(i).m_parent; + memPtr->m_jointDamping = getLink(i).m_jointDamping; + memPtr->m_jointFriction = getLink(i).m_jointFriction; + memPtr->m_jointLowerLimit = getLink(i).m_jointLowerLimit; + memPtr->m_jointUpperLimit = getLink(i).m_jointUpperLimit; + memPtr->m_jointMaxForce = getLink(i).m_jointMaxForce; + memPtr->m_jointMaxVelocity = getLink(i).m_jointMaxVelocity; + + getLink(i).m_eVector.serialize(memPtr->m_parentComToThisComOffset); + getLink(i).m_dVector.serialize(memPtr->m_thisPivotToThisComOffset); + getLink(i).m_zeroRotParentToThis.serialize(memPtr->m_zeroRotParentToThis); + btAssert(memPtr->m_dofCount<=3); + for (int dof = 0;dof<getLink(i).m_dofCount;dof++) + { + getLink(i).getAxisBottom(dof).serialize(memPtr->m_jointAxisBottom[dof]); + getLink(i).getAxisTop(dof).serialize(memPtr->m_jointAxisTop[dof]); + + memPtr->m_jointTorque[dof] = getLink(i).m_jointTorque[dof]; + memPtr->m_jointVel[dof] = getJointVelMultiDof(i)[dof]; + + } + int numPosVar = getLink(i).m_posVarCount; + for (int posvar = 0; posvar < numPosVar;posvar++) + { + memPtr->m_jointPos[posvar] = getLink(i).m_jointPos[posvar]; + } + + + { + char* name = (char*) serializer->findNameForPointer(m_links[i].m_linkName); + memPtr->m_linkName = (char*)serializer->getUniquePointer(name); + if (memPtr->m_linkName) + { + serializer->serializeName(name); + } + } + { + char* name = (char*) serializer->findNameForPointer(m_links[i].m_jointName); + memPtr->m_jointName = (char*)serializer->getUniquePointer(name); + if (memPtr->m_jointName) + { + serializer->serializeName(name); + } + } + memPtr->m_linkCollider = (btCollisionObjectData*)serializer->getUniquePointer(getLink(i).m_collider); + + } + serializer->finalizeChunk(chunk,btMultiBodyLinkDataName,BT_ARRAY_CODE,(void*) &m_links[0]); + } + mbd->m_links = mbd->m_numLinks? (btMultiBodyLinkData*) serializer->getUniquePointer((void*)&m_links[0]):0; + + // Fill padding with zeros to appease msan. +#ifdef BT_USE_DOUBLE_PRECISION + memset(mbd->m_padding, 0, sizeof(mbd->m_padding)); +#endif + + return btMultiBodyDataName; +} |