vpForceTwistMatrix.cpp

/*
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2025 by Inria. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See https://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 * Twist transformation matrix that allows to transform forces from one
 * frame to an other.
 */

 
#include <assert.h>
#include <sstream>
 
#include <visp3/core/vpException.h>
#include <visp3/core/vpForceTwistMatrix.h>
 
BEGIN_VISP_NAMESPACE
 
const unsigned int vpForceTwistMatrix::constr_value_6 = 6;

vpForceTwistMatrix &vpForceTwistMatrix::operator=(const vpForceTwistMatrix &M)
{
  const int val_6 = 6;
  for (int i = 0; i < val_6; ++i) {
    for (int j = 0; j < val_6; ++j) {
      rowPtrs[i][j] = M.rowPtrs[i][j];
    }
  }
 
  return *this;
}

void vpForceTwistMatrix::eye()
{
  const unsigned int nparam = 6;
  for (unsigned int i = 0; i < nparam; ++i) {
    for (unsigned int j = 0; j < nparam; ++j) {
      if (i == j) {
        (*this)[i][j] = 1.0;
      }
      else {
        (*this)[i][j] = 0.0;
      }
    }
  }
}

vpForceTwistMatrix::vpForceTwistMatrix() : vpArray2D<double>(constr_value_6, constr_value_6) { eye(); }

vpForceTwistMatrix::vpForceTwistMatrix(const vpForceTwistMatrix &F) : vpArray2D<double>(constr_value_6, constr_value_6) { *this = F; }

vpForceTwistMatrix::vpForceTwistMatrix(const vpHomogeneousMatrix &M, bool full) : vpArray2D<double>(constr_value_6, constr_value_6)
{
  if (full) {
    buildFrom(M);
  }
  else {
    buildFrom(M.getRotationMatrix());
  }
}

vpForceTwistMatrix::vpForceTwistMatrix(const vpTranslationVector &t, const vpThetaUVector &thetau)
  : vpArray2D<double>(constr_value_6, constr_value_6)
{
  buildFrom(t, thetau);
}

vpForceTwistMatrix::vpForceTwistMatrix(const vpThetaUVector &thetau) : vpArray2D<double>(constr_value_6, constr_value_6) { buildFrom(thetau); }

vpForceTwistMatrix::vpForceTwistMatrix(const vpTranslationVector &t, const vpRotationMatrix &R)
  : vpArray2D<double>(constr_value_6, constr_value_6)
{
  buildFrom(t, R);
}

vpForceTwistMatrix::vpForceTwistMatrix(const vpRotationMatrix &R) : vpArray2D<double>(constr_value_6, constr_value_6) { buildFrom(R); }

vpForceTwistMatrix::vpForceTwistMatrix(double tx, double ty, double tz, double tux, double tuy, double tuz)
  : vpArray2D<double>(constr_value_6, constr_value_6)
{
  vpTranslationVector T(tx, ty, tz);
  vpThetaUVector tu(tux, tuy, tuz);
  buildFrom(T, tu);
}

vpForceTwistMatrix vpForceTwistMatrix::operator*(const vpForceTwistMatrix &F) const
{
  vpForceTwistMatrix Fout;
  const unsigned int nparam = 6;
  for (unsigned int i = 0; i < nparam; ++i) {
    for (unsigned int j = 0; j < nparam; ++j) {
      double s = 0;
      for (unsigned int k = 0; k < nparam; ++k) {
        s += rowPtrs[i][k] * F.rowPtrs[k][j];
      }
      Fout[i][j] = s;
    }
  }
  return Fout;
}

vpMatrix vpForceTwistMatrix::operator*(const vpMatrix &M) const
{
  const unsigned int nparam = 6;
  if (nparam != M.getRows()) {
    throw(vpException(vpException::dimensionError,
                      "Cannot multiply (6x6) force/torque twist matrix by a (%dx%d) matrix", M.getRows(), M.getCols()));
  }
 
  unsigned int m_col = M.getCols();
  vpMatrix p(nparam, M.getCols());
  for (unsigned int i = 0; i < nparam; ++i) {
    for (unsigned int j = 0; j < m_col; ++j) {
      double s = 0;
      for (unsigned int k = 0; k < nparam; ++k) {
        s += rowPtrs[i][k] * M[k][j];
      }
      p[i][j] = s;
    }
  }
  return p;
}

vpColVector vpForceTwistMatrix::operator*(const vpColVector &H) const
{
  const unsigned int val_6 = 6;
  const unsigned int nparam = 6;
  vpColVector Hout(nparam);
 
  if (val_6 != H.getRows()) {
    throw(vpException(vpException::dimensionError,
                      "Cannot multiply a (6x6) force/torque twist matrix by "
                      "a %d dimension column vector",
                      H.getRows()));
  }
 
  Hout = 0.0;
 
  for (unsigned int i = 0; i < nparam; ++i) {
    for (unsigned int j = 0; j < nparam; ++j) {
      Hout[i] += rowPtrs[i][j] * H[j];
    }
  }
 
  return Hout;
}

vpForceTwistMatrix &vpForceTwistMatrix::buildFrom(const vpTranslationVector &t, const vpRotationMatrix &R)
{
  vpMatrix skewaR = t.skew(t) * R;
 
  const unsigned int val_3 = 3;
  const unsigned int index_3 = 3;
  for (unsigned int i = 0; i < val_3; ++i) {
    for (unsigned int j = 0; j < val_3; ++j) {
      (*this)[i][j] = R[i][j];
      (*this)[i + index_3][j + index_3] = R[i][j];
      (*this)[i + index_3][j] = skewaR[i][j];
    }
  }
  return *this;
}

vpForceTwistMatrix &vpForceTwistMatrix::buildFrom(const vpRotationMatrix &R)
{
  const unsigned int index_3 = 3;
  const unsigned int val_3 = 3;
  for (unsigned int i = 0; i < val_3; ++i) {
    for (unsigned int j = 0; j < val_3; ++j) {
      (*this)[i][j] = R[i][j];
      (*this)[i + index_3][j + index_3] = R[i][j];
      (*this)[i + index_3][j] = 0;
    }
  }
  return *this;
}

vpForceTwistMatrix &vpForceTwistMatrix::buildFrom(const vpTranslationVector &tv, const vpThetaUVector &thetau)
{
  buildFrom(tv, vpRotationMatrix(thetau));
  return *this;
}

vpForceTwistMatrix &vpForceTwistMatrix::buildFrom(const vpThetaUVector &thetau)
{
  buildFrom(vpRotationMatrix(thetau));
  return *this;
}

vpForceTwistMatrix &vpForceTwistMatrix::buildFrom(const vpHomogeneousMatrix &M, bool full)
{
  if (full) {
    buildFrom(M.getTranslationVector(), M.getRotationMatrix());
  }
  else {
    buildFrom(M.getRotationMatrix());
  }
 
  return *this;
}

int vpForceTwistMatrix::print(std::ostream &s, unsigned int length, char const *intro) const
{
  typedef std::string::size_type size_type;
 
  unsigned int m = getRows();
  unsigned int n = getCols();
 
  std::vector<std::string> values(m * n);
  std::ostringstream oss;
  std::ostringstream ossFixed;
  std::ios_base::fmtflags original_flags = oss.flags();
 
  // --comment: ossFixed less less std fixed
  ossFixed.setf(std::ios::fixed, std::ios::floatfield);
 
  size_type maxBefore = 0; // the length of the integral part
  size_type maxAfter = 0;  // number of decimals plus
  // one place for the decimal point
  for (unsigned int i = 0; i < m; ++i) {
    for (unsigned int j = 0; j < n; ++j) {
      oss.str("");
      oss << (*this)[i][j];
      if (oss.str().find("e") != std::string::npos) {
        ossFixed.str("");
        ossFixed << (*this)[i][j];
        oss.str(ossFixed.str());
      }
 
      values[(i * n) + j] = oss.str();
      size_type thislen = values[(i * n) + j].size();
      size_type p = values[(i * n) + j].find('.');
 
      if (p == std::string::npos) {
        maxBefore = vpMath::maximum(maxBefore, thislen);
        // maxAfter remains the same
      }
      else {
        maxBefore = vpMath::maximum(maxBefore, p);
        maxAfter = vpMath::maximum(maxAfter, thislen - p - 1);
      }
    }
  }
 
  size_type totalLength = length;
  // increase totalLength according to maxBefore
  totalLength = vpMath::maximum(totalLength, maxBefore);
  // decrease maxAfter according to totalLength
  maxAfter = std::min<size_type>(maxAfter, totalLength - maxBefore);
  if (maxAfter == 1) {
    maxAfter = 0;
  }
 
  // the following line is useful for debugging
  // std::cerr <<totalLength <<" " <<maxBefore <<" " <<maxAfter <<"\n";
 
  if (intro) {
    s << intro;
  }
  s << "[" << m << "," << n << "]=\n";
 
  for (unsigned int i = 0; i < m; ++i) {
    s << "  ";
    for (unsigned int j = 0; j < n; ++j) {
      size_type p = values[(i * n) + j].find('.');
      s.setf(std::ios::right, std::ios::adjustfield);
      s.width(static_cast<std::streamsize>(maxBefore));
      s << values[(i * n) + j].substr(0, p).c_str();
 
      if (maxAfter > 0) {
        s.setf(std::ios::left, std::ios::adjustfield);
        if (p != std::string::npos) {
          s.width(static_cast<std::streamsize>(maxAfter));
          s << values[(i * n) + j].substr(p, maxAfter).c_str();
        }
        else {
          assert(maxAfter > 1);
          s.width(static_cast<std::streamsize>(maxAfter));
          s << ".0";
        }
      }
 
      s << ' ';
    }
    s << std::endl;
  }
 
  s.flags(original_flags); // restore s to standard state
 
  return static_cast<int>(maxBefore + maxAfter);
}
 
#if defined(VISP_BUILD_DEPRECATED_FUNCTIONS)

void vpForceTwistMatrix::setIdentity() { eye(); }
 
#endif //#if defined(VISP_BUILD_DEPRECATED_FUNCTIONS)
#ifdef ENABLE_VISP_NAMESPACE
  }
#endif