vpFeatureMomentAlpha.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.
 *
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 * 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
 *
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 *
 * 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:
 * Implementation for alpha moment features.
 */
 
#include <visp3/core/vpMomentCentered.h>
#include <visp3/core/vpMomentGravityCenter.h>
#include <visp3/core/vpMomentObject.h>
#include <visp3/visual_features/vpFeatureMomentAlpha.h>
#include <visp3/visual_features/vpFeatureMomentCentered.h>
#include <visp3/visual_features/vpFeatureMomentDatabase.h>
 
#include <vector>
 
BEGIN_VISP_NAMESPACE
#ifdef VISP_MOMENTS_COMBINE_MATRICES

  void vpFeatureMomentAlpha::compute_interaction()
{
  bool found_moment_centered;
  bool found_FeatureMoment_centered;
 
  const vpMomentCentered &momentCentered =
    (static_cast<const vpMomentCentered &>(moments.get("vpMomentCentered", found_moment_centered)));
  vpFeatureMomentCentered &featureMomentCentered = (static_cast<vpFeatureMomentCentered &>(
    featureMomentsDataBase->get("vpFeatureMomentCentered", found_FeatureMoment_centered)));
 
  if (!found_moment_centered)
    throw vpException(vpException::notInitialized, "vpMomentCentered not found");
  if (!found_FeatureMoment_centered)
    throw vpException(vpException::notInitialized, "vpFeatureMomentCentered not found");
 
  double u11 = momentCentered.get(1, 1);
  double u20_u02 = momentCentered.get(2, 0) - momentCentered.get(0, 2);
  double dinv = 1 / (4 * u11 * u11 + u20_u02 * u20_u02);
  interaction_matrices[0].resize(1, 6);
  interaction_matrices[0] =
    (u20_u02 * dinv) * featureMomentCentered.interaction(1, 1) +
    (u11 * dinv) * (featureMomentCentered.interaction(0, 2) - featureMomentCentered.interaction(2, 0));
}
 
#else // #ifdef VISP_MOMENTS_COMBINE_MATRICES

  void vpFeatureMomentAlpha::compute_interaction()
{
  bool found_moment_centered;
  bool found_moment_gravity;
 
  const vpMomentCentered &momentCentered =
    static_cast<const vpMomentCentered &>(moments.get("vpMomentCentered", found_moment_centered));
  const vpMomentGravityCenter &momentGravity =
    static_cast<const vpMomentGravityCenter &>(moments.get("vpMomentGravityCenter", found_moment_gravity));
  const vpMomentObject &momentObject = moment->getObject();
 
  if (!found_moment_centered)
    throw vpException(vpException::notInitialized, "vpMomentCentered not found");
  if (!found_moment_gravity)
    throw vpException(vpException::notInitialized, "vpMomentGravityCenter not found");
 
  double mu11 = momentCentered.get(1, 1);
  double mu20 = momentCentered.get(2, 0);
  double mu02 = momentCentered.get(0, 2);
  double mu12 = momentCentered.get(1, 2);
  double mu21 = momentCentered.get(2, 1);
  double mu03 = momentCentered.get(0, 3);
  double mu30 = momentCentered.get(3, 0);
 
  double Xg = momentGravity.getXg();
  double Yg = momentGravity.getYg();
 
  double Avx, Avy, Avz, Awx, Awy;
  double beta = (momentObject.getType() == vpMomentObject::DISCRETE) ? 2 : 5;
 
  double d = (mu20 - mu02) * (mu20 - mu02) + 4 * mu11 * mu11;
  double DA = mu20 + mu02;
  double DA_2 = DA * DA;
  double mu11_2 = mu11 * mu11;
 
  Avx = mu11 * DA * A / d + (DA * mu02 + (0.5) * d - (0.5) * DA_2) * B / d;
  Avy = (DA * mu02 - (0.5) * d - (.5) * DA_2) * A / d - B * mu11 * DA / d;
 
  Awx = (beta * (mu12 * (mu20 - mu02) + mu11 * (mu03 - mu21)) + Xg * (mu02 * (mu20 - mu02) - 2 * mu11_2) +
         Yg * mu11 * (mu20 + mu02)) /
    d;
  Awy = (beta * (mu21 * (mu02 - mu20) + mu11 * (mu30 - mu12)) + Xg * mu11 * (mu20 + mu02) +
         Yg * (mu20 * (mu02 - mu20) - 2 * mu11_2)) /
    d;
 
  Avz = B * Awx - A * Awy;
  interaction_matrices.resize(1);
  interaction_matrices[0].resize(1, 6);
 
  int VX = 0;
  int VY = 1;
  int VZ = 2;
  int WX = 3;
  int WY = 4;
  int WZ = 5;
 
  interaction_matrices[0][0][VX] = Avx;
  interaction_matrices[0][0][VY] = Avy;
  interaction_matrices[0][0][VZ] = Avz;
 
  interaction_matrices[0][0][WX] = Awx;
  interaction_matrices[0][0][WY] = Awy;
  interaction_matrices[0][0][WZ] = -1.;
}
 
#endif // #ifdef VISP_MOMENTS_COMBINE_MATRICES
 
vpColVector vpFeatureMomentAlpha::error(const vpBasicFeature &s_star, const unsigned int /* select */)
{
  vpColVector e(0);
  double err = s[0] - s_star[0];
 
  if (err < -M_PI)
    err += 2 * M_PI;
  if (err > M_PI)
    err -= 2 * M_PI;
 
  vpColVector ecv(1);
  ecv[0] = err;
  e = vpColVector::stack(e, ecv);
 
  return e;
}
END_VISP_NAMESPACE