Armature.cpp

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/*
 * Armature.cpp
 *
 *  Created on: Feb 3, 2009
 *      Author: benoitbolsee
 */

#include "Armature.hpp"
#include <algorithm>
#include <string.h>
#include <stdlib.h>

namespace iTaSC {

// a joint constraint is characterized by 5 values: tolerance, K, alpha, yd, yddot
static const unsigned int constraintCacheSize = 5;
std::string Armature::m_root = "root";

Armature::Armature():
    ControlledObject(),
    m_tree(),
    m_njoint(0),
    m_nconstraint(0),
    m_noutput(0),
    m_neffector(0),
    m_finalized(false),
    m_cache(NULL),
    m_buf(NULL),
    m_qCCh(-1),
    m_qCTs(0),
    m_yCCh(-1),
    m_yCTs(0),
    m_qKdl(),
    m_oldqKdl(),
    m_newqKdl(),
    m_qdotKdl(),
    m_jac(NULL),
    m_armlength(0.0),
    m_jacsolver(NULL),
    m_fksolver(NULL)
{
}

Armature::~Armature()
{
    if (m_jac)
        delete m_jac;
    if (m_jacsolver)
        delete m_jacsolver;
    if (m_fksolver)
        delete m_fksolver;
    for (JointConstraintList::iterator it=m_constraints.begin(); it != m_constraints.end(); it++) {
        if (*it != NULL)
            delete (*it);
    }
    if (m_buf)
        delete [] m_buf;
    m_constraints.clear();
}

Armature::JointConstraint_struct::JointConstraint_struct(SegmentMap::const_iterator _segment, unsigned int _y_nr, ConstraintCallback _function, void* _param, bool _freeParam, bool _substep):
    segment(_segment), value(), values(), function(_function), y_nr(_y_nr), param(_param), freeParam(_freeParam), substep(_substep)
{
    memset(values, 0, sizeof(values));
    memset(value, 0, sizeof(value));
    values[0].feedback = 20.0;
    values[1].feedback = 20.0;
    values[2].feedback = 20.0;
    values[0].tolerance = 1.0;
    values[1].tolerance = 1.0;
    values[2].tolerance = 1.0;
    values[0].values = &value[0];
    values[1].values = &value[1];
    values[2].values = &value[2];
    values[0].number = 1;
    values[1].number = 1;
    values[2].number = 1;
    switch (segment->second.segment.getJoint().getType()) {
    case Joint::RotX:
        value[0].id = ID_JOINT_RX;      
        values[0].id = ID_JOINT_RX;     
        v_nr = 1;
        break;
    case Joint::RotY:
        value[0].id = ID_JOINT_RY;      
        values[0].id = ID_JOINT_RY;     
        v_nr = 1;
        break;
    case Joint::RotZ:
        value[0].id = ID_JOINT_RZ;      
        values[0].id = ID_JOINT_RZ;     
        v_nr = 1;
        break;
    case Joint::TransX:
        value[0].id = ID_JOINT_TX;      
        values[0].id = ID_JOINT_TX;     
        v_nr = 1;
        break;
    case Joint::TransY:
        value[0].id = ID_JOINT_TY;      
        values[0].id = ID_JOINT_TY;     
        v_nr = 1;
        break;
    case Joint::TransZ:
        value[0].id = ID_JOINT_TZ;      
        values[0].id = ID_JOINT_TZ;     
        v_nr = 1;
        break;
    case Joint::Sphere:
        values[0].id = value[0].id = ID_JOINT_RX;       
        values[1].id = value[1].id = ID_JOINT_RY;
        values[2].id = value[2].id = ID_JOINT_RZ;       
        v_nr = 3;
        break;
    case Joint::Swing:
        values[0].id = value[0].id = ID_JOINT_RX;       
        values[1].id = value[1].id = ID_JOINT_RZ;       
        v_nr = 2;
        break;
    case Joint::None:
        break;
    }
}

Armature::JointConstraint_struct::~JointConstraint_struct()
{
    if (freeParam && param)
        free(param);
}

void Armature::initCache(Cache *_cache)
{
    m_cache = _cache;
    m_qCCh = -1;
    m_yCCh = -1;
    m_buf = NULL;
    if (m_cache) {
        // add a special channel for the joint
        m_qCCh = m_cache->addChannel(this, "q", m_qKdl.rows()*sizeof(double));
#if 0
        // for the constraints, instead of creating many different channels, we will
        // create a single channel for all the constraints
        if (m_nconstraint) {
            m_yCCh = m_cache->addChannel(this, "y", m_nconstraint*constraintCacheSize*sizeof(double));
            m_buf = new double[m_nconstraint*constraintCacheSize];
        }
        // store the initial cache position at timestamp 0
        pushConstraints(0);
#endif
        pushQ(0);
    }
}

void Armature::pushQ(CacheTS timestamp)
{
    if (m_qCCh >= 0) {
        // try to keep the cache if the joints are the same
        m_cache->addCacheVectorIfDifferent(this, m_qCCh, timestamp, &m_qKdl(0), m_qKdl.rows(), KDL::epsilon);
        m_qCTs = timestamp;
    }
}

/* return true if a m_cache position was loaded */
bool Armature::popQ(CacheTS timestamp)
{
    if (m_qCCh >= 0) {
        double* item;
        item = (double*)m_cache->getPreviousCacheItem(this, m_qCCh, &timestamp);
        if (item && m_qCTs != timestamp) {
            double& q = m_qKdl(0);
            memcpy(&q, item, m_qKdl.rows()*sizeof(q));
            m_qCTs = timestamp;
            // changing the joint => recompute the jacobian
            updateJacobian();
        }
        return (item) ? true : false;
    }
    return true;
}
#if 0
void Armature::pushConstraints(CacheTS timestamp)
{
    if (m_yCCh >= 0) {
        double *buf = NULL;
        if (m_nconstraint) {
            double *item = m_buf;
            for (unsigned int i=0; i<m_nconstraint; i++) {
                JointConstraint_struct* pConstraint = m_constraints[i];
                *item++ = pConstraint->values.feedback;
                *item++ = pConstraint->values.tolerance;
                *item++ = pConstraint->value.yd;
                *item++ = pConstraint->value.yddot;
                *item++ = pConstraint->values.alpha;
            }
        }
        m_cache->addCacheVectorIfDifferent(this, m_yCCh, timestamp, m_buf, m_nconstraint*constraintCacheSize, KDL::epsilon);
        m_yCTs = timestamp;
    }
}

/* return true if a cache position was loaded */
bool Armature::popConstraints(CacheTS timestamp)
{
    if (m_yCCh >= 0) {
        double *item = (double*)m_cache->getPreviousCacheItem(this, m_yCCh, &timestamp);
        if (item && m_yCTs != timestamp) {
            for (unsigned int i=0; i<m_nconstraint; i++) {
                JointConstraint_struct* pConstraint = m_constraints[i];
                if (pConstraint->function != Joint1DOFLimitCallback) {
                    pConstraint->values.feedback = *item++;
                    pConstraint->values.tolerance = *item++;
                    pConstraint->value.yd = *item++;
                    pConstraint->value.yddot = *item++;
                    pConstraint->values.alpha = *item++;
                } else {
                    item += constraintCacheSize;
                }
            }
            m_yCTs = timestamp;
        }
        return (item) ? true : false;
    }
    return true;
}
#endif

bool Armature::addSegment(const std::string& segment_name, const std::string& hook_name, const Joint& joint, const double& q_rest, const Frame& f_tip, const Inertia& M)
{
    if (m_finalized)
        return false;

    Segment segment(joint, f_tip, M);
    if (!m_tree.addSegment(segment, segment_name, hook_name))
        return false;
    int ndof = joint.getNDof();
    for (int dof=0; dof<ndof; dof++) {
        Joint_struct js(joint.getType(), ndof, (&q_rest)[dof]);
        m_joints.push_back(js);
    }
    m_njoint+=ndof;
    return true;
}

bool Armature::getSegment(const std::string& name, const unsigned int q_size, const Joint* &p_joint, double &q_rest, double &q, const Frame* &p_tip)
{
    SegmentMap::const_iterator sit = m_tree.getSegment(name);
    if (sit == m_tree.getSegments().end())
        return false;
    p_joint = &sit->second.segment.getJoint();
    if (q_size < p_joint->getNDof())
        return false;
    p_tip = &sit->second.segment.getFrameToTip();
    for (unsigned int dof=0; dof<p_joint->getNDof(); dof++) {
        (&q_rest)[dof] = m_joints[sit->second.q_nr+dof].rest;
        (&q)[dof] = m_qKdl(sit->second.q_nr+dof);
    }
    return true;
}

double Armature::getMaxJointChange()
{
    if (!m_finalized)
        return 0.0;
    double maxJoint = 0.0;
    for (unsigned int i=0; i<m_njoint; i++) {
        // this is a very rough calculation, it doesn't work well for spherical joint
        double joint = fabs(m_oldqKdl(i)-m_qKdl(i));
        if (maxJoint < joint)
            maxJoint = joint;
    }
    return maxJoint;
}

double Armature::getMaxEndEffectorChange()
{
    if (!m_finalized)
        return 0.0;
    double maxDelta = 0.0;
    double delta;
    Twist twist;
    for (unsigned int i = 0; i<m_neffector; i++) {
        twist = diff(m_effectors[i].pose, m_effectors[i].oldpose);
        delta = twist.rot.Norm();
        if (delta > maxDelta)
            maxDelta = delta;
        delta = twist.vel.Norm();
        if (delta > maxDelta)
            maxDelta = delta;
    }
    return maxDelta;
}

int Armature::addConstraint(const std::string& segment_name, ConstraintCallback _function, void* _param, bool _freeParam, bool _substep)
{
    SegmentMap::const_iterator segment_it = m_tree.getSegment(segment_name);
    // not suitable for NDof joints
    if (segment_it == m_tree.getSegments().end()) {
        if (_freeParam && _param)
            free(_param);
        return -1;
    }
    JointConstraintList::iterator constraint_it;
    JointConstraint_struct* pConstraint;
    int iConstraint;
    for (iConstraint=0, constraint_it=m_constraints.begin(); constraint_it != m_constraints.end(); constraint_it++, iConstraint++) {
        pConstraint = *constraint_it;
        if (pConstraint->segment == segment_it) {
            // redefining a constraint
            if (pConstraint->freeParam && pConstraint->param) {
                free(pConstraint->param);
            }
            pConstraint->function = _function;
            pConstraint->param = _param;
            pConstraint->freeParam = _freeParam;
            pConstraint->substep = _substep;
            return iConstraint;
        }
    }
    if (m_finalized)  {
        if (_freeParam && _param)
            free(_param);
        return -1;
    }
    // new constraint, append
    pConstraint = new JointConstraint_struct(segment_it, m_noutput, _function, _param, _freeParam, _substep);
    m_constraints.push_back(pConstraint);
    m_noutput += pConstraint->v_nr;
    return m_nconstraint++;
}

int Armature::addLimitConstraint(const std::string& segment_name, unsigned int dof, double _min, double _max)
{
    SegmentMap::const_iterator segment_it = m_tree.getSegment(segment_name);
    if (segment_it == m_tree.getSegments().end())
        return -1;
    const Joint& joint = segment_it->second.segment.getJoint();
    if (joint.getNDof() != 1 && joint.getType() != Joint::Swing) {
        // not suitable for Sphere joints
        return -1;
    }
    if ((joint.getNDof() == 1 && dof > 0) || (joint.getNDof() == 2 && dof > 1))
        return -1;
    Joint_struct& p_joint = m_joints[segment_it->second.q_nr+dof];
    p_joint.min = _min;
    p_joint.max = _max;
    p_joint.useLimit = true;
    return 0;
}

int Armature::addEndEffector(const std::string& name)
{
    const SegmentMap& segments = m_tree.getSegments();
    if (segments.find(name) == segments.end())
        return -1;

    EffectorList::const_iterator it;
    int ee;
    for (it=m_effectors.begin(), ee=0; it!=m_effectors.end(); it++, ee++) {
        if (it->name == name)
            return ee;
    }
    if (m_finalized)
        return -1;
    Effector_struct effector(name);
    m_effectors.push_back(effector);
    return m_neffector++;
}

void Armature::finalize()
{
    unsigned int i, j, c;
    if (m_finalized)
        return;
    initialize(m_njoint, m_noutput, m_neffector);
    for (i=c=0; i<m_nconstraint; i++) {
        JointConstraint_struct* pConstraint = m_constraints[i];
        for (j=0; j<pConstraint->v_nr; j++, c++) {
            m_Cq(c,pConstraint->segment->second.q_nr+j) = 1.0;
            m_Wy(c) = pConstraint->values[j].alpha/*/(pConstraint->values.tolerance*pConstraint->values.feedback)*/;
        }
    }
    m_jacsolver= new KDL::TreeJntToJacSolver(m_tree);
    m_fksolver = new KDL::TreeFkSolverPos_recursive(m_tree);
    m_jac = new Jacobian(m_njoint);
    m_qKdl.resize(m_njoint);
    m_oldqKdl.resize(m_njoint);
    m_newqKdl.resize(m_njoint);
    m_qdotKdl.resize(m_njoint);
    for (i=0; i<m_njoint; i++) {
        m_newqKdl(i) = m_oldqKdl(i) = m_qKdl(i) = m_joints[i].rest;
    }
    updateJacobian();
    // estimate the maximum size of the robot arms
    double length;
    m_armlength = 0.0;
    for (i=0; i<m_neffector; i++) {
        length = 0.0;
        KDL::SegmentMap::const_iterator sit = m_tree.getSegment(m_effectors[i].name);
        while (sit->first != "root") {
            Frame tip = sit->second.segment.pose(m_qKdl(sit->second.q_nr));
            length += tip.p.Norm();
            sit = sit->second.parent;
        }
        if (length > m_armlength)
            m_armlength = length;
    }
    if (m_armlength < KDL::epsilon)
        m_armlength = KDL::epsilon;
    m_finalized = true;
}

void Armature::pushCache(const Timestamp& timestamp)
{
    if (!timestamp.substep && timestamp.cache) {
        pushQ(timestamp.cacheTimestamp);
        //pushConstraints(timestamp.cacheTimestamp);
    }
}

bool Armature::setJointArray(const KDL::JntArray& joints)
{
    if (!m_finalized)
        return false;
    if (joints.rows() != m_qKdl.rows())
        return false;
    m_qKdl = joints;
    updateJacobian();
    return true;
}

const KDL::JntArray& Armature::getJointArray()
{
    return m_qKdl;
}

bool Armature::updateJoint(const Timestamp& timestamp, JointLockCallback& callback)
{
    if (!m_finalized)
        return false;
    
    // integration and joint limit
    // for spherical joint we must use a more sophisticated method
    unsigned int q_nr;
    double* qdot=&m_qdotKdl(0);
    double* q=&m_qKdl(0);
    double* newq=&m_newqKdl(0);
    double norm, qx, qz, CX, CZ, sx, sz;
    bool locked = false;
    int unlocked = 0;

    for (q_nr=0; q_nr<m_nq; ++q_nr)
        m_qdotKdl(q_nr)=m_qdot(q_nr);

    for (q_nr=0; q_nr<m_nq; ) {
        Joint_struct* joint = &m_joints[q_nr];
        if (!joint->locked) {
            switch (joint->type) {
            case KDL::Joint::Swing:
            {
                KDL::Rotation base = KDL::Rot(KDL::Vector(q[0],0.0,q[1]));
                (base*KDL::Rot(KDL::Vector(qdot[0],0.0,qdot[1])*timestamp.realTimestep)).GetXZRot().GetValue(newq);
                if (joint[0].useLimit) {
                    if (joint[1].useLimit) {
                        // elliptical limit
                        sx = sz = 1.0;
                        qx = newq[0];
                        qz = newq[1];
                        // determine in which quadrant we are
                        if (qx > 0.0 && qz > 0.0) {
                            CX = joint[0].max;
                            CZ = joint[1].max;
                        } else if (qx <= 0.0 && qz > 0.0) {
                            CX = -joint[0].min;
                            CZ = joint[1].max;
                            qx = -qx;
                            sx = -1.0;
                        } else if (qx <= 0.0 && qz <= 0.0) {
                            CX = -joint[0].min;
                            CZ = -joint[1].min;
                            qx = -qx;
                            qz = -qz;
                            sx = sz = -1.0;
                        } else {
                            CX = joint[0].max;
                            CZ = -joint[0].min;
                            qz = -qz;
                            sz = -1.0;
                        }
                        if (CX < KDL::epsilon || CZ < KDL::epsilon) {
                            // quadrant is degenerated
                            if (qx > CX) {
                                newq[0] = CX*sx;
                                joint[0].locked = true;
                            }
                            if (qz > CZ) {
                                newq[1] = CZ*sz;
                                joint[0].locked = true;
                            }
                        } else {
                            // general case
                            qx /= CX;
                            qz /= CZ;
                            norm = KDL::sqrt(KDL::sqr(qx)+KDL::sqr(qz));
                            if (norm > 1.0) {
                                norm = 1.0/norm;
                                newq[0] = qx*norm*CX*sx;
                                newq[1] = qz*norm*CZ*sz;
                                joint[0].locked = true;
                            }
                        }
                    } else {
                        // limit on X only
                        qx = newq[0];
                        if (qx > joint[0].max) {
                            newq[0] = joint[0].max;
                            joint[0].locked = true;
                        } else if (qx < joint[0].min) {
                            newq[0] = joint[0].min;
                            joint[0].locked = true;
                        }
                    }
                } else if (joint[1].useLimit) {
                    // limit on Z only
                    qz = newq[1];
                    if (qz > joint[1].max) {
                        newq[1] = joint[1].max;
                        joint[0].locked = true;
                    } else if (qz < joint[1].min) {
                        newq[1] = joint[1].min;
                        joint[0].locked = true;
                    }
                }
                if (joint[0].locked) {
                    // check the difference from previous position
                    locked = true;
                    norm = KDL::sqr(newq[0]-q[0])+KDL::sqr(newq[1]-q[1]);
                    if (norm < KDL::epsilon2) {
                        // joint didn't move, no need to update the jacobian
                        callback.lockJoint(q_nr, 2);
                    } else {
                        // joint moved, compute the corresponding velocity
                        double deltaq[2];
                        (base.Inverse()*KDL::Rot(KDL::Vector(newq[0],0.0,newq[1]))).GetXZRot().GetValue(deltaq);
                        deltaq[0] /= timestamp.realTimestep;
                        deltaq[1] /= timestamp.realTimestep;
                        callback.lockJoint(q_nr, 2, deltaq);
                        // no need to update the other joints, it will be done after next rerun
                        goto end_loop;
                    }
                } else
                    unlocked++;
                break;
            }
            case KDL::Joint::Sphere:
            {
                (KDL::Rot(KDL::Vector(q))*KDL::Rot(KDL::Vector(qdot)*timestamp.realTimestep)).GetRot().GetValue(newq);
                // no limit on this joint
                unlocked++;
                break;
            }
            default:
                for (unsigned int i=0; i<joint->ndof; i++) {
                    newq[i] = q[i]+qdot[i]*timestamp.realTimestep;
                    if (joint[i].useLimit) {
                        if (newq[i] > joint[i].max) {
                            newq[i] = joint[i].max;
                            joint[0].locked = true;
                        } else if (newq[i] < joint[i].min) {
                            newq[i] = joint[i].min;
                            joint[0].locked = true;
                        }
                    }
                }
                if (joint[0].locked) {
                    locked = true;
                    norm = 0.0;
                    // compute delta to locked position
                    for (unsigned int i=0; i<joint->ndof; i++) {
                        qdot[i] = newq[i] - q[i];
                        norm += qdot[i]*qdot[i];
                    }
                    if (norm < KDL::epsilon2) {
                        // joint didn't move, no need to update the jacobian
                        callback.lockJoint(q_nr, joint->ndof);
                    } else {
                        // solver needs velocity, compute equivalent velocity
                        for (unsigned int i=0; i<joint->ndof; i++) {
                            qdot[i] /= timestamp.realTimestep;
                        }
                        callback.lockJoint(q_nr, joint->ndof, qdot);
                        goto end_loop;
                    }
                } else 
                    unlocked++;
            }
        }
        qdot += joint->ndof;
        q    += joint->ndof;
        newq += joint->ndof;
        q_nr += joint->ndof;
    }
end_loop:
    // check if there any other unlocked joint
    for ( ; q_nr<m_nq; ) {
        Joint_struct* joint = &m_joints[q_nr];
        if (!joint->locked)
            unlocked++;
        q_nr += joint->ndof;
    }
    // if all joints have been locked no need to run the solver again
    return (unlocked) ? locked : false;
}

void Armature::updateKinematics(const Timestamp& timestamp){

    //Integrate m_qdot
    if (!m_finalized)
        return;

    // the new joint value have been computed already, just copy
    memcpy(&m_qKdl(0), &m_newqKdl(0), sizeof(double)*m_qKdl.rows());
    pushCache(timestamp);
    updateJacobian();
    // here update the desired output.
    // We assume constant desired output for the joint limit constraint, no need to update it.
}

void Armature::updateJacobian()
{
    //calculate pose and jacobian
    for (unsigned int ee=0; ee<m_nee; ee++) {
        m_fksolver->JntToCart(m_qKdl,m_effectors[ee].pose,m_effectors[ee].name,m_root);
        m_jacsolver->JntToJac(m_qKdl,*m_jac,m_effectors[ee].name);
        // get the jacobian for the base point, to prepare transformation to world reference
        changeRefPoint(*m_jac,-m_effectors[ee].pose.p,*m_jac);
        //copy to Jq:
        e_matrix& Jq = m_JqArray[ee];
        for(unsigned int i=0;i<6;i++) {
            for(unsigned int j=0;j<m_nq;j++)
                Jq(i,j)=(*m_jac)(i,j);
        }
    }
    // remember that this object has moved 
    m_updated = true;
}

const Frame& Armature::getPose(const unsigned int ee)
{
    if (!m_finalized)
        return F_identity;
    return (ee >= m_nee) ? F_identity : m_effectors[ee].pose;
}

bool Armature::getRelativeFrame(Frame& result, const std::string& segment_name, const std::string& base_name)
{
    if (!m_finalized)
        return false;
    return (m_fksolver->JntToCart(m_qKdl,result,segment_name,base_name) < 0) ? false : true;
}

void Armature::updateControlOutput(const Timestamp& timestamp)
{
    if (!m_finalized)
        return;


    if (!timestamp.substep && !timestamp.reiterate && timestamp.interpolate) {
        popQ(timestamp.cacheTimestamp);
        //popConstraints(timestamp.cacheTimestamp);
    }

    if (!timestamp.substep) {
        // save previous joint state for getMaxJointChange()
        memcpy(&m_oldqKdl(0), &m_qKdl(0), sizeof(double)*m_qKdl.rows());
        for (unsigned int i=0; i<m_neffector; i++) {
            m_effectors[i].oldpose = m_effectors[i].pose;
        }
    }

    // remove all joint lock
    for (JointList::iterator jit=m_joints.begin(); jit!=m_joints.end(); ++jit) {
        (*jit).locked = false;
    }

    JointConstraintList::iterator it;
    unsigned int iConstraint;

    // scan through the constraints and call the callback functions
    for (iConstraint=0, it=m_constraints.begin(); it!=m_constraints.end(); it++, iConstraint++) {
        JointConstraint_struct* pConstraint = *it;
        unsigned int nr, i;
        for (i=0, nr = pConstraint->segment->second.q_nr; i<pConstraint->v_nr; i++, nr++) {
            *(double*)&pConstraint->value[i].y = m_qKdl(nr);
            *(double*)&pConstraint->value[i].ydot = m_qdotKdl(nr);
        }
        if (pConstraint->function && (pConstraint->substep || (!timestamp.reiterate && !timestamp.substep))) {
            (*pConstraint->function)(timestamp, pConstraint->values, pConstraint->v_nr, pConstraint->param);
        }
        // recompute the weight in any case, that's the most likely modification
        for (i=0, nr=pConstraint->y_nr; i<pConstraint->v_nr; i++, nr++) {
            m_Wy(nr) = pConstraint->values[i].alpha/*/(pConstraint->values.tolerance*pConstraint->values.feedback)*/;
            m_ydot(nr)=pConstraint->value[i].yddot+pConstraint->values[i].feedback*(pConstraint->value[i].yd-pConstraint->value[i].y);
        }
    }
}

bool Armature::setControlParameter(unsigned int constraintId, unsigned int valueId, ConstraintAction action, double value, double timestep)
{
    unsigned int lastid, i;
    if (constraintId == CONSTRAINT_ID_ALL) {
        constraintId = 0;
        lastid = m_nconstraint;
    } else if (constraintId < m_nconstraint) {
        lastid = constraintId+1;
    } else {
        return false;
    }
    for ( ; constraintId<lastid; ++constraintId) {
        JointConstraint_struct* pConstraint = m_constraints[constraintId];
        if (valueId == ID_JOINT) {
            for (i=0; i<pConstraint->v_nr; i++) {
                switch (action) {
                case ACT_TOLERANCE:
                    pConstraint->values[i].tolerance = value;
                    break;
                case ACT_FEEDBACK:
                    pConstraint->values[i].feedback = value;
                    break;
                case ACT_ALPHA:
                    pConstraint->values[i].alpha = value;
                    break;
                default:
                    break;
                }
            }
        } else {
            for (i=0; i<pConstraint->v_nr; i++) {
                if (valueId == pConstraint->value[i].id) {
                    switch (action) {
                    case ACT_VALUE:
                        pConstraint->value[i].yd = value;
                        break;
                    case ACT_VELOCITY:
                        pConstraint->value[i].yddot = value;
                        break;
                    case ACT_TOLERANCE:
                        pConstraint->values[i].tolerance = value;
                        break;
                    case ACT_FEEDBACK:
                        pConstraint->values[i].feedback = value;
                        break;
                    case ACT_ALPHA:
                        pConstraint->values[i].alpha = value;
                        break;
                    case ACT_NONE:
                        break;
                    }
                }
            }
        }
        if (m_finalized) {
            for (i=0; i<pConstraint->v_nr; i++) 
                m_Wy(pConstraint->y_nr+i) = pConstraint->values[i].alpha/*/(pConstraint->values.tolerance*pConstraint->values.feedback)*/;
        }
    }
    return true;
}

}