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@@ -0,0 +1,955 @@
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+#include "ndt_omp.h"
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+/*
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+ * Software License Agreement (BSD License)
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+ *
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+ * Point Cloud Library (PCL) - www.pointclouds.org
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+ * Copyright (c) 2010-2011, Willow Garage, Inc.
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+ * Copyright (c) 2012-, Open Perception, Inc.
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+ *
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+ * All rights reserved.
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+ *
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+ * Redistribution and use in source and binary forms, with or without
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+ * modification, are permitted provided that the following conditions
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+ * are met:
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+ *
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+ * * Redistributions of source code must retain the above copyright
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+ * notice, this list of conditions and the following disclaimer.
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+ * * Redistributions in binary form must reproduce the above
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+ * copyright notice, this list of conditions and the following
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+ * disclaimer in the documentation and/or other materials provided
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+ * with the distribution.
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+ * * Neither the name of the copyright holder(s) nor the names of its
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+ * contributors may be used to endorse or promote products derived
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+ * from this software without specific prior written permission.
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+ *
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+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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+ * POSSIBILITY OF SUCH DAMAGE.
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+ *
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+ * $Id$
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+ *
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+ */
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+
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+#ifndef PCL_REGISTRATION_NDT_OMP_IMPL_H_
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+#define PCL_REGISTRATION_NDT_OMP_IMPL_H_
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+
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+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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+template<typename PointSource, typename PointTarget>
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+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::NormalDistributionsTransform ()
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+ : target_cells_ ()
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+ , resolution_ (1.0f)
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+ , step_size_ (0.1)
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+ , outlier_ratio_ (0.55)
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+ , gauss_d1_ ()
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+ , gauss_d2_ ()
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+ , gauss_d3_ ()
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+ , trans_probability_ ()
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+ , j_ang_a_ (), j_ang_b_ (), j_ang_c_ (), j_ang_d_ (), j_ang_e_ (), j_ang_f_ (), j_ang_g_ (), j_ang_h_ ()
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+ , h_ang_a2_ (), h_ang_a3_ (), h_ang_b2_ (), h_ang_b3_ (), h_ang_c2_ (), h_ang_c3_ (), h_ang_d1_ (), h_ang_d2_ ()
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+ , h_ang_d3_ (), h_ang_e1_ (), h_ang_e2_ (), h_ang_e3_ (), h_ang_f1_ (), h_ang_f2_ (), h_ang_f3_ ()
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+{
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+ reg_name_ = "NormalDistributionsTransform";
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+
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+ double gauss_c1, gauss_c2;
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+
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+ // Initializes the guassian fitting parameters (eq. 6.8) [Magnusson 2009]
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+ gauss_c1 = 10.0 * (1 - outlier_ratio_);
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+ gauss_c2 = outlier_ratio_ / pow (resolution_, 3);
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+ gauss_d3_ = -log (gauss_c2);
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+ gauss_d1_ = -log ( gauss_c1 + gauss_c2 ) - gauss_d3_;
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+ gauss_d2_ = -2 * log ((-log ( gauss_c1 * exp ( -0.5 ) + gauss_c2 ) - gauss_d3_) / gauss_d1_);
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+
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+ transformation_epsilon_ = 0.1;
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+ max_iterations_ = 35;
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+
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+ search_method = DIRECT7;
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+ num_threads_ = omp_get_max_threads();
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+}
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+
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+
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+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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+template<typename PointSource, typename PointTarget> void
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+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computeTransformation (PointCloudSource &output, const Eigen::Matrix4f &guess)
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+{
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+ nr_iterations_ = 0;
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+ converged_ = false;
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+
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+ double gauss_c1, gauss_c2;
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+
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+ // Initializes the guassian fitting parameters (eq. 6.8) [Magnusson 2009]
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+ gauss_c1 = 10 * (1 - outlier_ratio_);
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+ gauss_c2 = outlier_ratio_ / pow (resolution_, 3);
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+ gauss_d3_ = -log (gauss_c2);
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+ gauss_d1_ = -log ( gauss_c1 + gauss_c2 ) - gauss_d3_;
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+ gauss_d2_ = -2 * log ((-log ( gauss_c1 * exp ( -0.5 ) + gauss_c2 ) - gauss_d3_) / gauss_d1_);
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+
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+ if (guess != Eigen::Matrix4f::Identity ())
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+ {
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+ // Initialise final transformation to the guessed one
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+ final_transformation_ = guess;
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+ // Apply guessed transformation prior to search for neighbours
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+ transformPointCloud (output, output, guess);
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+ }
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+
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+ Eigen::Transform<float, 3, Eigen::Affine, Eigen::ColMajor> eig_transformation;
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+ eig_transformation.matrix () = final_transformation_;
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+
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+ // Convert initial guess matrix to 6 element transformation vector
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+ Eigen::Matrix<double, 6, 1> p, delta_p, score_gradient;
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+ Eigen::Vector3f init_translation = eig_transformation.translation ();
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+ Eigen::Vector3f init_rotation = eig_transformation.rotation ().eulerAngles (0, 1, 2);
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+ p << init_translation (0), init_translation (1), init_translation (2),
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+ init_rotation (0), init_rotation (1), init_rotation (2);
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+
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+ Eigen::Matrix<double, 6, 6> hessian;
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+
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+ double score = 0;
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+ double delta_p_norm;
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+
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+ // Calculate derivates of initial transform vector, subsequent derivative calculations are done in the step length determination.
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+ score = computeDerivatives (score_gradient, hessian, output, p);
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+
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+ while (!converged_)
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+ {
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+ // Store previous transformation
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+ previous_transformation_ = transformation_;
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+
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+ // Solve for decent direction using newton method, line 23 in Algorithm 2 [Magnusson 2009]
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+ Eigen::JacobiSVD<Eigen::Matrix<double, 6, 6> > sv (hessian, Eigen::ComputeFullU | Eigen::ComputeFullV);
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+ // Negative for maximization as opposed to minimization
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+ delta_p = sv.solve (-score_gradient);
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+
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+ //Calculate step length with guarnteed sufficient decrease [More, Thuente 1994]
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+ delta_p_norm = delta_p.norm ();
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+
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+ if (delta_p_norm == 0 || delta_p_norm != delta_p_norm)
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+ {
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+ trans_probability_ = score / static_cast<double> (input_->points.size ());
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+ converged_ = delta_p_norm == delta_p_norm;
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+ return;
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+ }
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+
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+ delta_p.normalize ();
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+ delta_p_norm = computeStepLengthMT (p, delta_p, delta_p_norm, step_size_, transformation_epsilon_ / 2, score, score_gradient, hessian, output);
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+ delta_p *= delta_p_norm;
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+
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+
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+ transformation_ = (Eigen::Translation<float, 3> (static_cast<float> (delta_p (0)), static_cast<float> (delta_p (1)), static_cast<float> (delta_p (2))) *
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+ Eigen::AngleAxis<float> (static_cast<float> (delta_p (3)), Eigen::Vector3f::UnitX ()) *
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+ Eigen::AngleAxis<float> (static_cast<float> (delta_p (4)), Eigen::Vector3f::UnitY ()) *
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+ Eigen::AngleAxis<float> (static_cast<float> (delta_p (5)), Eigen::Vector3f::UnitZ ())).matrix ();
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+
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+
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+ p = p + delta_p;
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+
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+ // Update Visualizer (untested)
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+ if (update_visualizer_ != 0)
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+ update_visualizer_ (output, std::vector<int>(), *target_, std::vector<int>() );
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+
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+ if (nr_iterations_ > max_iterations_ ||
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+ (nr_iterations_ && (std::fabs (delta_p_norm) < transformation_epsilon_)))
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+ {
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+ converged_ = true;
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+ }
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+
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+ nr_iterations_++;
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+
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+ }
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+
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+ // Store transformation probability. The realtive differences within each scan registration are accurate
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+ // but the normalization constants need to be modified for it to be globally accurate
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+ trans_probability_ = score / static_cast<double> (input_->points.size ());
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+}
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+
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+#ifndef _OPENMP
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+int omp_get_max_threads() { return 1; }
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+int omp_get_thread_num() { return 0; }
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+#endif
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+
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+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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+template<typename PointSource, typename PointTarget> double
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+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computeDerivatives(Eigen::Matrix<double, 6, 1> &score_gradient,
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+ Eigen::Matrix<double, 6, 6> &hessian,
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+ PointCloudSource &trans_cloud,
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+ Eigen::Matrix<double, 6, 1> &p,
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+ bool compute_hessian)
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+{
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+ score_gradient.setZero();
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+ hessian.setZero();
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+ double score = 0;
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+
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+ std::vector<double> scores(num_threads_);
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+ std::vector<Eigen::Matrix<double, 6, 1>, Eigen::aligned_allocator<Eigen::Matrix<double, 6, 1>>> score_gradients(num_threads_);
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+ std::vector<Eigen::Matrix<double, 6, 6>, Eigen::aligned_allocator<Eigen::Matrix<double, 6, 6>>> hessians(num_threads_);
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+ for (int i = 0; i < num_threads_; i++) {
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+ scores[i] = 0;
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+ score_gradients[i].setZero();
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+ hessians[i].setZero();
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+ }
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+
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+ // Precompute Angular Derivatives (eq. 6.19 and 6.21)[Magnusson 2009]
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+ computeAngleDerivatives(p);
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+
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+ std::vector<std::vector<TargetGridLeafConstPtr>> neighborhoods(num_threads_);
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+ std::vector<std::vector<float>> distancess(num_threads_);
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+
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+ // Update gradient and hessian for each point, line 17 in Algorithm 2 [Magnusson 2009]
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+#pragma omp parallel for num_threads(num_threads_) schedule(guided, 8)
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+ for (int idx = 0; idx < input_->points.size(); idx++)
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+ {
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+ int thread_n = omp_get_thread_num();
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+
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+ // Original Point and Transformed Point
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+ PointSource x_pt, x_trans_pt;
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+ // Original Point and Transformed Point (for math)
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+ Eigen::Vector3d x, x_trans;
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+ // Occupied Voxel
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+ TargetGridLeafConstPtr cell;
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+ // Inverse Covariance of Occupied Voxel
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+ Eigen::Matrix3d c_inv;
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+
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+ // Initialize Point Gradient and Hessian
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+ Eigen::Matrix<float, 4, 6> point_gradient_;
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+ Eigen::Matrix<float, 24, 6> point_hessian_;
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+ point_gradient_.setZero();
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+ point_gradient_.block<3, 3>(0, 0).setIdentity();
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+ point_hessian_.setZero();
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+
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+ x_trans_pt = trans_cloud.points[idx];
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+
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+ auto& neighborhood = neighborhoods[thread_n];
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+ auto& distances = distancess[thread_n];
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+
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+ // Find nieghbors (Radius search has been experimentally faster than direct neighbor checking.
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+ switch (search_method) {
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+ case KDTREE:
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+ target_cells_.radiusSearch(x_trans_pt, resolution_, neighborhood, distances);
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+ break;
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+ case DIRECT26:
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+ target_cells_.getNeighborhoodAtPoint(x_trans_pt, neighborhood);
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+ break;
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+ default:
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+ case DIRECT7:
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+ target_cells_.getNeighborhoodAtPoint7(x_trans_pt, neighborhood);
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+ break;
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+ case DIRECT1:
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+ target_cells_.getNeighborhoodAtPoint1(x_trans_pt, neighborhood);
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+ break;
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+ }
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+
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+ double score_pt = 0;
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+ Eigen::Matrix<double, 6, 1> score_gradient_pt = Eigen::Matrix<double, 6, 1>::Zero();
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+ Eigen::Matrix<double, 6, 6> hessian_pt = Eigen::Matrix<double, 6, 6>::Zero();
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+
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+ for (typename std::vector<TargetGridLeafConstPtr>::iterator neighborhood_it = neighborhood.begin(); neighborhood_it != neighborhood.end(); neighborhood_it++)
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+ {
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+ cell = *neighborhood_it;
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+ x_pt = input_->points[idx];
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+ x = Eigen::Vector3d(x_pt.x, x_pt.y, x_pt.z);
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+
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+ x_trans = Eigen::Vector3d(x_trans_pt.x, x_trans_pt.y, x_trans_pt.z);
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+
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+ // Denorm point, x_k' in Equations 6.12 and 6.13 [Magnusson 2009]
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+ x_trans -= cell->getMean();
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+ // Uses precomputed covariance for speed.
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+ c_inv = cell->getInverseCov();
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+
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+ // Compute derivative of transform function w.r.t. transform vector, J_E and H_E in Equations 6.18 and 6.20 [Magnusson 2009]
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+ computePointDerivatives(x, point_gradient_, point_hessian_);
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+ // Update score, gradient and hessian, lines 19-21 in Algorithm 2, according to Equations 6.10, 6.12 and 6.13, respectively [Magnusson 2009]
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+ score_pt += updateDerivatives(score_gradient_pt, hessian_pt, point_gradient_, point_hessian_, x_trans, c_inv, compute_hessian);
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+ }
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+
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+ scores[thread_n] += score_pt;
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+ score_gradients[thread_n].noalias() += score_gradient_pt;
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+ hessians[thread_n].noalias() += hessian_pt;
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+ }
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+
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+ for (int i = 0; i < num_threads_; i++) {
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+ score += scores[i];
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+ score_gradient += score_gradients[i];
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+ hessian += hessians[i];
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+ }
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+
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+ return (score);
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+}
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+
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+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
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+template<typename PointSource, typename PointTarget> void
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+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computeAngleDerivatives(Eigen::Matrix<double, 6, 1> &p, bool compute_hessian)
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+{
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+ // Simplified math for near 0 angles
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+ double cx, cy, cz, sx, sy, sz;
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+ if (fabs(p(3)) < 10e-5)
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+ {
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+ //p(3) = 0;
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+ cx = 1.0;
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+ sx = 0.0;
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+ }
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+ else
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+ {
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+ cx = cos(p(3));
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+ sx = sin(p(3));
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+ }
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+ if (fabs(p(4)) < 10e-5)
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+ {
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+ //p(4) = 0;
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+ cy = 1.0;
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+ sy = 0.0;
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+ }
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+ else
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+ {
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+ cy = cos(p(4));
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+ sy = sin(p(4));
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+ }
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+
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+ if (fabs(p(5)) < 10e-5)
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+ {
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+ //p(5) = 0;
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+ cz = 1.0;
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+ sz = 0.0;
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+ }
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+ else
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+ {
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+ cz = cos(p(5));
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+ sz = sin(p(5));
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+ }
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+
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+ // Precomputed angular gradiant components. Letters correspond to Equation 6.19 [Magnusson 2009]
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+ j_ang_a_ << (-sx * sz + cx * sy * cz), (-sx * cz - cx * sy * sz), (-cx * cy);
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+ j_ang_b_ << (cx * sz + sx * sy * cz), (cx * cz - sx * sy * sz), (-sx * cy);
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+ j_ang_c_ << (-sy * cz), sy * sz, cy;
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+ j_ang_d_ << sx * cy * cz, (-sx * cy * sz), sx * sy;
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+ j_ang_e_ << (-cx * cy * cz), cx * cy * sz, (-cx * sy);
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+ j_ang_f_ << (-cy * sz), (-cy * cz), 0;
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+ j_ang_g_ << (cx * cz - sx * sy * sz), (-cx * sz - sx * sy * cz), 0;
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+ j_ang_h_ << (sx * cz + cx * sy * sz), (cx * sy * cz - sx * sz), 0;
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+
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+ j_ang.setZero();
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+ j_ang.row(0).noalias() = Eigen::Vector4f((-sx * sz + cx * sy * cz), (-sx * cz - cx * sy * sz), (-cx * cy), 0.0f);
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+ j_ang.row(1).noalias() = Eigen::Vector4f((cx * sz + sx * sy * cz), (cx * cz - sx * sy * sz), (-sx * cy), 0.0f);
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+ j_ang.row(2).noalias() = Eigen::Vector4f((-sy * cz), sy * sz, cy, 0.0f);
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+ j_ang.row(3).noalias() = Eigen::Vector4f(sx * cy * cz, (-sx * cy * sz), sx * sy, 0.0f);
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+ j_ang.row(4).noalias() = Eigen::Vector4f((-cx * cy * cz), cx * cy * sz, (-cx * sy), 0.0f);
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+ j_ang.row(5).noalias() = Eigen::Vector4f((-cy * sz), (-cy * cz), 0, 0.0f);
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+ j_ang.row(6).noalias() = Eigen::Vector4f((cx * cz - sx * sy * sz), (-cx * sz - sx * sy * cz), 0, 0.0f);
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+ j_ang.row(7).noalias() = Eigen::Vector4f((sx * cz + cx * sy * sz), (cx * sy * cz - sx * sz), 0, 0.0f);
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|
+
|
|
|
+ if (compute_hessian)
|
|
|
+ {
|
|
|
+ // Precomputed angular hessian components. Letters correspond to Equation 6.21 and numbers correspond to row index [Magnusson 2009]
|
|
|
+ h_ang_a2_ << (-cx * sz - sx * sy * cz), (-cx * cz + sx * sy * sz), sx * cy;
|
|
|
+ h_ang_a3_ << (-sx * sz + cx * sy * cz), (-cx * sy * sz - sx * cz), (-cx * cy);
|
|
|
+
|
|
|
+ h_ang_b2_ << (cx * cy * cz), (-cx * cy * sz), (cx * sy);
|
|
|
+ h_ang_b3_ << (sx * cy * cz), (-sx * cy * sz), (sx * sy);
|
|
|
+
|
|
|
+ h_ang_c2_ << (-sx * cz - cx * sy * sz), (sx * sz - cx * sy * cz), 0;
|
|
|
+ h_ang_c3_ << (cx * cz - sx * sy * sz), (-sx * sy * cz - cx * sz), 0;
|
|
|
+
|
|
|
+ h_ang_d1_ << (-cy * cz), (cy * sz), (sy);
|
|
|
+ h_ang_d2_ << (-sx * sy * cz), (sx * sy * sz), (sx * cy);
|
|
|
+ h_ang_d3_ << (cx * sy * cz), (-cx * sy * sz), (-cx * cy);
|
|
|
+
|
|
|
+ h_ang_e1_ << (sy * sz), (sy * cz), 0;
|
|
|
+ h_ang_e2_ << (-sx * cy * sz), (-sx * cy * cz), 0;
|
|
|
+ h_ang_e3_ << (cx * cy * sz), (cx * cy * cz), 0;
|
|
|
+
|
|
|
+ h_ang_f1_ << (-cy * cz), (cy * sz), 0;
|
|
|
+ h_ang_f2_ << (-cx * sz - sx * sy * cz), (-cx * cz + sx * sy * sz), 0;
|
|
|
+ h_ang_f3_ << (-sx * sz + cx * sy * cz), (-cx * sy * sz - sx * cz), 0;
|
|
|
+
|
|
|
+ h_ang.setZero();
|
|
|
+ h_ang.row(0).noalias() = Eigen::Vector4f((-cx * sz - sx * sy * cz), (-cx * cz + sx * sy * sz), sx * cy, 0.0f); // a2
|
|
|
+ h_ang.row(1).noalias() = Eigen::Vector4f((-sx * sz + cx * sy * cz), (-cx * sy * sz - sx * cz), (-cx * cy), 0.0f); // a3
|
|
|
+
|
|
|
+ h_ang.row(2).noalias() = Eigen::Vector4f((cx * cy * cz), (-cx * cy * sz), (cx * sy), 0.0f); // b2
|
|
|
+ h_ang.row(3).noalias() = Eigen::Vector4f((sx * cy * cz), (-sx * cy * sz), (sx * sy), 0.0f); // b3
|
|
|
+
|
|
|
+ h_ang.row(4).noalias() = Eigen::Vector4f((-sx * cz - cx * sy * sz), (sx * sz - cx * sy * cz), 0, 0.0f); // c2
|
|
|
+ h_ang.row(5).noalias() = Eigen::Vector4f((cx * cz - sx * sy * sz), (-sx * sy * cz - cx * sz), 0, 0.0f); // c3
|
|
|
+
|
|
|
+ h_ang.row(6).noalias() = Eigen::Vector4f((-cy * cz), (cy * sz), (sy), 0.0f); // d1
|
|
|
+ h_ang.row(7).noalias() = Eigen::Vector4f((-sx * sy * cz), (sx * sy * sz), (sx * cy), 0.0f); // d2
|
|
|
+ h_ang.row(8).noalias() = Eigen::Vector4f((cx * sy * cz), (-cx * sy * sz), (-cx * cy), 0.0f); // d3
|
|
|
+
|
|
|
+ h_ang.row(9).noalias() = Eigen::Vector4f((sy * sz), (sy * cz), 0, 0.0f); // e1
|
|
|
+ h_ang.row(10).noalias() = Eigen::Vector4f ((-sx * cy * sz), (-sx * cy * cz), 0, 0.0f); // e2
|
|
|
+ h_ang.row(11).noalias() = Eigen::Vector4f ((cx * cy * sz), (cx * cy * cz), 0, 0.0f); // e3
|
|
|
+
|
|
|
+ h_ang.row(12).noalias() = Eigen::Vector4f ((-cy * cz), (cy * sz), 0, 0.0f); // f1
|
|
|
+ h_ang.row(13).noalias() = Eigen::Vector4f ((-cx * sz - sx * sy * cz), (-cx * cz + sx * sy * sz), 0, 0.0f); // f2
|
|
|
+ h_ang.row(14).noalias() = Eigen::Vector4f ((-sx * sz + cx * sy * cz), (-cx * sy * sz - sx * cz), 0, 0.0f); // f3
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> void
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computePointDerivatives(Eigen::Vector3d &x, Eigen::Matrix<float, 4, 6>& point_gradient_, Eigen::Matrix<float, 24, 6>& point_hessian_, bool compute_hessian) const
|
|
|
+{
|
|
|
+ Eigen::Vector4f x4(x[0], x[1], x[2], 0.0f);
|
|
|
+
|
|
|
+ // Calculate first derivative of Transformation Equation 6.17 w.r.t. transform vector p.
|
|
|
+ // Derivative w.r.t. ith element of transform vector corresponds to column i, Equation 6.18 and 6.19 [Magnusson 2009]
|
|
|
+ Eigen::Matrix<float, 8, 1> x_j_ang = j_ang * x4;
|
|
|
+
|
|
|
+ point_gradient_(1, 3) = x_j_ang[0];
|
|
|
+ point_gradient_(2, 3) = x_j_ang[1];
|
|
|
+ point_gradient_(0, 4) = x_j_ang[2];
|
|
|
+ point_gradient_(1, 4) = x_j_ang[3];
|
|
|
+ point_gradient_(2, 4) = x_j_ang[4];
|
|
|
+ point_gradient_(0, 5) = x_j_ang[5];
|
|
|
+ point_gradient_(1, 5) = x_j_ang[6];
|
|
|
+ point_gradient_(2, 5) = x_j_ang[7];
|
|
|
+
|
|
|
+ if (compute_hessian)
|
|
|
+ {
|
|
|
+ Eigen::Matrix<float, 16, 1> x_h_ang = h_ang * x4;
|
|
|
+
|
|
|
+ // Vectors from Equation 6.21 [Magnusson 2009]
|
|
|
+ Eigen::Vector4f a (0, x_h_ang[0], x_h_ang[1], 0.0f);
|
|
|
+ Eigen::Vector4f b (0, x_h_ang[2], x_h_ang[3], 0.0f);
|
|
|
+ Eigen::Vector4f c (0, x_h_ang[4], x_h_ang[5], 0.0f);
|
|
|
+ Eigen::Vector4f d (x_h_ang[6], x_h_ang[7], x_h_ang[8], 0.0f);
|
|
|
+ Eigen::Vector4f e (x_h_ang[9], x_h_ang[10], x_h_ang[11], 0.0f);
|
|
|
+ Eigen::Vector4f f (x_h_ang[12], x_h_ang[13], x_h_ang[14], 0.0f);
|
|
|
+
|
|
|
+ // Calculate second derivative of Transformation Equation 6.17 w.r.t. transform vector p.
|
|
|
+ // Derivative w.r.t. ith and jth elements of transform vector corresponds to the 3x1 block matrix starting at (3i,j), Equation 6.20 and 6.21 [Magnusson 2009]
|
|
|
+ point_hessian_.block<4, 1>((9/3)*4, 3) = a;
|
|
|
+ point_hessian_.block<4, 1>((12/3)*4, 3) = b;
|
|
|
+ point_hessian_.block<4, 1>((15/3)*4, 3) = c;
|
|
|
+ point_hessian_.block<4, 1>((9/3)*4, 4) = b;
|
|
|
+ point_hessian_.block<4, 1>((12/3)*4, 4) = d;
|
|
|
+ point_hessian_.block<4, 1>((15/3)*4, 4) = e;
|
|
|
+ point_hessian_.block<4, 1>((9/3)*4, 5) = c;
|
|
|
+ point_hessian_.block<4, 1>((12/3)*4, 5) = e;
|
|
|
+ point_hessian_.block<4, 1>((15/3)*4, 5) = f;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> void
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computePointDerivatives(Eigen::Vector3d &x, Eigen::Matrix<double, 3, 6>& point_gradient_, Eigen::Matrix<double, 18, 6>& point_hessian_, bool compute_hessian) const
|
|
|
+{
|
|
|
+ // Calculate first derivative of Transformation Equation 6.17 w.r.t. transform vector p.
|
|
|
+ // Derivative w.r.t. ith element of transform vector corresponds to column i, Equation 6.18 and 6.19 [Magnusson 2009]
|
|
|
+ point_gradient_(1, 3) = x.dot(j_ang_a_);
|
|
|
+ point_gradient_(2, 3) = x.dot(j_ang_b_);
|
|
|
+ point_gradient_(0, 4) = x.dot(j_ang_c_);
|
|
|
+ point_gradient_(1, 4) = x.dot(j_ang_d_);
|
|
|
+ point_gradient_(2, 4) = x.dot(j_ang_e_);
|
|
|
+ point_gradient_(0, 5) = x.dot(j_ang_f_);
|
|
|
+ point_gradient_(1, 5) = x.dot(j_ang_g_);
|
|
|
+ point_gradient_(2, 5) = x.dot(j_ang_h_);
|
|
|
+
|
|
|
+ if (compute_hessian)
|
|
|
+ {
|
|
|
+ // Vectors from Equation 6.21 [Magnusson 2009]
|
|
|
+ Eigen::Vector3d a, b, c, d, e, f;
|
|
|
+
|
|
|
+ a << 0, x.dot(h_ang_a2_), x.dot(h_ang_a3_);
|
|
|
+ b << 0, x.dot(h_ang_b2_), x.dot(h_ang_b3_);
|
|
|
+ c << 0, x.dot(h_ang_c2_), x.dot(h_ang_c3_);
|
|
|
+ d << x.dot(h_ang_d1_), x.dot(h_ang_d2_), x.dot(h_ang_d3_);
|
|
|
+ e << x.dot(h_ang_e1_), x.dot(h_ang_e2_), x.dot(h_ang_e3_);
|
|
|
+ f << x.dot(h_ang_f1_), x.dot(h_ang_f2_), x.dot(h_ang_f3_);
|
|
|
+
|
|
|
+ // Calculate second derivative of Transformation Equation 6.17 w.r.t. transform vector p.
|
|
|
+ // Derivative w.r.t. ith and jth elements of transform vector corresponds to the 3x1 block matrix starting at (3i,j), Equation 6.20 and 6.21 [Magnusson 2009]
|
|
|
+ point_hessian_.block<3, 1>(9, 3) = a;
|
|
|
+ point_hessian_.block<3, 1>(12, 3) = b;
|
|
|
+ point_hessian_.block<3, 1>(15, 3) = c;
|
|
|
+ point_hessian_.block<3, 1>(9, 4) = b;
|
|
|
+ point_hessian_.block<3, 1>(12, 4) = d;
|
|
|
+ point_hessian_.block<3, 1>(15, 4) = e;
|
|
|
+ point_hessian_.block<3, 1>(9, 5) = c;
|
|
|
+ point_hessian_.block<3, 1>(12, 5) = e;
|
|
|
+ point_hessian_.block<3, 1>(15, 5) = f;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> double
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::updateDerivatives(Eigen::Matrix<double, 6, 1> &score_gradient,
|
|
|
+ Eigen::Matrix<double, 6, 6> &hessian,
|
|
|
+ const Eigen::Matrix<float, 4, 6> &point_gradient4,
|
|
|
+ const Eigen::Matrix<float, 24, 6> &point_hessian_,
|
|
|
+ const Eigen::Vector3d &x_trans, const Eigen::Matrix3d &c_inv,
|
|
|
+ bool compute_hessian) const
|
|
|
+{
|
|
|
+ Eigen::Matrix<float, 1, 4> x_trans4( x_trans[0], x_trans[1], x_trans[2], 0.0f );
|
|
|
+ Eigen::Matrix4f c_inv4 = Eigen::Matrix4f::Zero();
|
|
|
+ c_inv4.topLeftCorner(3, 3) = c_inv.cast<float>();
|
|
|
+
|
|
|
+ float gauss_d2 = gauss_d2_;
|
|
|
+
|
|
|
+ // e^(-d_2/2 * (x_k - mu_k)^T Sigma_k^-1 (x_k - mu_k)) Equation 6.9 [Magnusson 2009]
|
|
|
+ float e_x_cov_x = exp(-gauss_d2 * x_trans4.dot(x_trans4 * c_inv4) * 0.5f);
|
|
|
+ // Calculate probability of transtormed points existance, Equation 6.9 [Magnusson 2009]
|
|
|
+ float score_inc = -gauss_d1_ * e_x_cov_x;
|
|
|
+
|
|
|
+ e_x_cov_x = gauss_d2 * e_x_cov_x;
|
|
|
+
|
|
|
+ // Error checking for invalid values.
|
|
|
+ if (e_x_cov_x > 1 || e_x_cov_x < 0 || e_x_cov_x != e_x_cov_x)
|
|
|
+ return (0);
|
|
|
+
|
|
|
+ // Reusable portion of Equation 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ e_x_cov_x *= gauss_d1_;
|
|
|
+
|
|
|
+ Eigen::Matrix<float, 4, 6> c_inv4_x_point_gradient4 = c_inv4 * point_gradient4;
|
|
|
+ Eigen::Matrix<float, 6, 1> x_trans4_dot_c_inv4_x_point_gradient4 = x_trans4 * c_inv4_x_point_gradient4;
|
|
|
+
|
|
|
+ score_gradient.noalias() += (e_x_cov_x * x_trans4_dot_c_inv4_x_point_gradient4).cast<double>();
|
|
|
+
|
|
|
+ if (compute_hessian) {
|
|
|
+ Eigen::Matrix<float, 1, 4> x_trans4_x_c_inv4 = x_trans4 * c_inv4;
|
|
|
+ Eigen::Matrix<float, 6, 6> point_gradient4_colj_dot_c_inv4_x_point_gradient4_col_i = point_gradient4.transpose() * c_inv4_x_point_gradient4;
|
|
|
+ Eigen::Matrix<float, 6, 1> x_trans4_dot_c_inv4_x_ext_point_hessian_4ij;
|
|
|
+
|
|
|
+ for (int i = 0; i < 6; i++) {
|
|
|
+ // Sigma_k^-1 d(T(x,p))/dpi, Reusable portion of Equation 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ // Update gradient, Equation 6.12 [Magnusson 2009]
|
|
|
+ x_trans4_dot_c_inv4_x_ext_point_hessian_4ij.noalias() = x_trans4_x_c_inv4 * point_hessian_.block<4, 6>(i * 4, 0);
|
|
|
+
|
|
|
+ for (int j = 0; j < hessian.cols(); j++) {
|
|
|
+ // Update hessian, Equation 6.13 [Magnusson 2009]
|
|
|
+ hessian(i, j) += e_x_cov_x * (-gauss_d2 * x_trans4_dot_c_inv4_x_point_gradient4(i) * x_trans4_dot_c_inv4_x_point_gradient4(j) +
|
|
|
+ x_trans4_dot_c_inv4_x_ext_point_hessian_4ij(j) +
|
|
|
+ point_gradient4_colj_dot_c_inv4_x_point_gradient4_col_i(j, i));
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ return (score_inc);
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> void
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computeHessian (Eigen::Matrix<double, 6, 6> &hessian,
|
|
|
+ PointCloudSource &trans_cloud, Eigen::Matrix<double, 6, 1> &)
|
|
|
+{
|
|
|
+ // Original Point and Transformed Point
|
|
|
+ PointSource x_pt, x_trans_pt;
|
|
|
+ // Original Point and Transformed Point (for math)
|
|
|
+ Eigen::Vector3d x, x_trans;
|
|
|
+ // Occupied Voxel
|
|
|
+ TargetGridLeafConstPtr cell;
|
|
|
+ // Inverse Covariance of Occupied Voxel
|
|
|
+ Eigen::Matrix3d c_inv;
|
|
|
+
|
|
|
+ // Initialize Point Gradient and Hessian
|
|
|
+ Eigen::Matrix<double, 3, 6> point_gradient_;
|
|
|
+ Eigen::Matrix<double, 18, 6> point_hessian_;
|
|
|
+ point_gradient_.setZero();
|
|
|
+ point_gradient_.block<3, 3>(0, 0).setIdentity();
|
|
|
+ point_hessian_.setZero();
|
|
|
+
|
|
|
+ hessian.setZero ();
|
|
|
+
|
|
|
+ // Precompute Angular Derivatives unessisary because only used after regular derivative calculation
|
|
|
+
|
|
|
+ // Update hessian for each point, line 17 in Algorithm 2 [Magnusson 2009]
|
|
|
+ for (size_t idx = 0; idx < input_->points.size (); idx++)
|
|
|
+ {
|
|
|
+ x_trans_pt = trans_cloud.points[idx];
|
|
|
+
|
|
|
+ // Find nieghbors (Radius search has been experimentally faster than direct neighbor checking.
|
|
|
+ std::vector<TargetGridLeafConstPtr> neighborhood;
|
|
|
+ std::vector<float> distances;
|
|
|
+ target_cells_.radiusSearch (x_trans_pt, resolution_, neighborhood, distances);
|
|
|
+
|
|
|
+ for (typename std::vector<TargetGridLeafConstPtr>::iterator neighborhood_it = neighborhood.begin (); neighborhood_it != neighborhood.end (); neighborhood_it++)
|
|
|
+ {
|
|
|
+ cell = *neighborhood_it;
|
|
|
+
|
|
|
+ {
|
|
|
+ x_pt = input_->points[idx];
|
|
|
+ x = Eigen::Vector3d (x_pt.x, x_pt.y, x_pt.z);
|
|
|
+
|
|
|
+ x_trans = Eigen::Vector3d (x_trans_pt.x, x_trans_pt.y, x_trans_pt.z);
|
|
|
+
|
|
|
+ // Denorm point, x_k' in Equations 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ x_trans -= cell->getMean ();
|
|
|
+ // Uses precomputed covariance for speed.
|
|
|
+ c_inv = cell->getInverseCov ();
|
|
|
+
|
|
|
+ // Compute derivative of transform function w.r.t. transform vector, J_E and H_E in Equations 6.18 and 6.20 [Magnusson 2009]
|
|
|
+ computePointDerivatives (x, point_gradient_, point_hessian_);
|
|
|
+ // Update hessian, lines 21 in Algorithm 2, according to Equations 6.10, 6.12 and 6.13, respectively [Magnusson 2009]
|
|
|
+ updateHessian (hessian, point_gradient_, point_hessian_, x_trans, c_inv);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> void
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::updateHessian (Eigen::Matrix<double, 6, 6> &hessian,
|
|
|
+ const Eigen::Matrix<double, 3, 6> &point_gradient_,
|
|
|
+ const Eigen::Matrix<double, 18, 6> &point_hessian_,
|
|
|
+ const Eigen::Vector3d &x_trans,
|
|
|
+ const Eigen::Matrix3d &c_inv) const
|
|
|
+{
|
|
|
+ Eigen::Vector3d cov_dxd_pi;
|
|
|
+ // e^(-d_2/2 * (x_k - mu_k)^T Sigma_k^-1 (x_k - mu_k)) Equation 6.9 [Magnusson 2009]
|
|
|
+ double e_x_cov_x = gauss_d2_ * exp (-gauss_d2_ * x_trans.dot (c_inv * x_trans) / 2);
|
|
|
+
|
|
|
+ // Error checking for invalid values.
|
|
|
+ if (e_x_cov_x > 1 || e_x_cov_x < 0 || e_x_cov_x != e_x_cov_x)
|
|
|
+ return;
|
|
|
+
|
|
|
+ // Reusable portion of Equation 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ e_x_cov_x *= gauss_d1_;
|
|
|
+
|
|
|
+ for (int i = 0; i < 6; i++)
|
|
|
+ {
|
|
|
+ // Sigma_k^-1 d(T(x,p))/dpi, Reusable portion of Equation 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ cov_dxd_pi = c_inv * point_gradient_.col (i);
|
|
|
+
|
|
|
+ for (int j = 0; j < hessian.cols (); j++)
|
|
|
+ {
|
|
|
+ // Update hessian, Equation 6.13 [Magnusson 2009]
|
|
|
+ hessian (i, j) += e_x_cov_x * (-gauss_d2_ * x_trans.dot (cov_dxd_pi) * x_trans.dot (c_inv * point_gradient_.col (j)) +
|
|
|
+ x_trans.dot (c_inv * point_hessian_.block<3, 1>(3 * i, j)) +
|
|
|
+ point_gradient_.col (j).dot (cov_dxd_pi) );
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> bool
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::updateIntervalMT (double &a_l, double &f_l, double &g_l,
|
|
|
+ double &a_u, double &f_u, double &g_u,
|
|
|
+ double a_t, double f_t, double g_t)
|
|
|
+{
|
|
|
+ // Case U1 in Update Algorithm and Case a in Modified Update Algorithm [More, Thuente 1994]
|
|
|
+ if (f_t > f_l)
|
|
|
+ {
|
|
|
+ a_u = a_t;
|
|
|
+ f_u = f_t;
|
|
|
+ g_u = g_t;
|
|
|
+ return (false);
|
|
|
+ }
|
|
|
+ // Case U2 in Update Algorithm and Case b in Modified Update Algorithm [More, Thuente 1994]
|
|
|
+ else
|
|
|
+ if (g_t * (a_l - a_t) > 0)
|
|
|
+ {
|
|
|
+ a_l = a_t;
|
|
|
+ f_l = f_t;
|
|
|
+ g_l = g_t;
|
|
|
+ return (false);
|
|
|
+ }
|
|
|
+ // Case U3 in Update Algorithm and Case c in Modified Update Algorithm [More, Thuente 1994]
|
|
|
+ else
|
|
|
+ if (g_t * (a_l - a_t) < 0)
|
|
|
+ {
|
|
|
+ a_u = a_l;
|
|
|
+ f_u = f_l;
|
|
|
+ g_u = g_l;
|
|
|
+
|
|
|
+ a_l = a_t;
|
|
|
+ f_l = f_t;
|
|
|
+ g_l = g_t;
|
|
|
+ return (false);
|
|
|
+ }
|
|
|
+ // Interval Converged
|
|
|
+ else
|
|
|
+ return (true);
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> double
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::trialValueSelectionMT (double a_l, double f_l, double g_l,
|
|
|
+ double a_u, double f_u, double g_u,
|
|
|
+ double a_t, double f_t, double g_t)
|
|
|
+{
|
|
|
+ // Case 1 in Trial Value Selection [More, Thuente 1994]
|
|
|
+ if (f_t > f_l)
|
|
|
+ {
|
|
|
+ // Calculate the minimizer of the cubic that interpolates f_l, f_t, g_l and g_t
|
|
|
+ // Equation 2.4.52 [Sun, Yuan 2006]
|
|
|
+ double z = 3 * (f_t - f_l) / (a_t - a_l) - g_t - g_l;
|
|
|
+ double w = std::sqrt (z * z - g_t * g_l);
|
|
|
+ // Equation 2.4.56 [Sun, Yuan 2006]
|
|
|
+ double a_c = a_l + (a_t - a_l) * (w - g_l - z) / (g_t - g_l + 2 * w);
|
|
|
+
|
|
|
+ // Calculate the minimizer of the quadratic that interpolates f_l, f_t and g_l
|
|
|
+ // Equation 2.4.2 [Sun, Yuan 2006]
|
|
|
+ double a_q = a_l - 0.5 * (a_l - a_t) * g_l / (g_l - (f_l - f_t) / (a_l - a_t));
|
|
|
+
|
|
|
+ if (std::fabs (a_c - a_l) < std::fabs (a_q - a_l))
|
|
|
+ return (a_c);
|
|
|
+ else
|
|
|
+ return (0.5 * (a_q + a_c));
|
|
|
+ }
|
|
|
+ // Case 2 in Trial Value Selection [More, Thuente 1994]
|
|
|
+ else
|
|
|
+ if (g_t * g_l < 0)
|
|
|
+ {
|
|
|
+ // Calculate the minimizer of the cubic that interpolates f_l, f_t, g_l and g_t
|
|
|
+ // Equation 2.4.52 [Sun, Yuan 2006]
|
|
|
+ double z = 3 * (f_t - f_l) / (a_t - a_l) - g_t - g_l;
|
|
|
+ double w = std::sqrt (z * z - g_t * g_l);
|
|
|
+ // Equation 2.4.56 [Sun, Yuan 2006]
|
|
|
+ double a_c = a_l + (a_t - a_l) * (w - g_l - z) / (g_t - g_l + 2 * w);
|
|
|
+
|
|
|
+ // Calculate the minimizer of the quadratic that interpolates f_l, g_l and g_t
|
|
|
+ // Equation 2.4.5 [Sun, Yuan 2006]
|
|
|
+ double a_s = a_l - (a_l - a_t) / (g_l - g_t) * g_l;
|
|
|
+
|
|
|
+ if (std::fabs (a_c - a_t) >= std::fabs (a_s - a_t))
|
|
|
+ return (a_c);
|
|
|
+ else
|
|
|
+ return (a_s);
|
|
|
+ }
|
|
|
+ // Case 3 in Trial Value Selection [More, Thuente 1994]
|
|
|
+ else
|
|
|
+ if (std::fabs (g_t) <= std::fabs (g_l))
|
|
|
+ {
|
|
|
+ // Calculate the minimizer of the cubic that interpolates f_l, f_t, g_l and g_t
|
|
|
+ // Equation 2.4.52 [Sun, Yuan 2006]
|
|
|
+ double z = 3 * (f_t - f_l) / (a_t - a_l) - g_t - g_l;
|
|
|
+ double w = std::sqrt (z * z - g_t * g_l);
|
|
|
+ double a_c = a_l + (a_t - a_l) * (w - g_l - z) / (g_t - g_l + 2 * w);
|
|
|
+
|
|
|
+ // Calculate the minimizer of the quadratic that interpolates g_l and g_t
|
|
|
+ // Equation 2.4.5 [Sun, Yuan 2006]
|
|
|
+ double a_s = a_l - (a_l - a_t) / (g_l - g_t) * g_l;
|
|
|
+
|
|
|
+ double a_t_next;
|
|
|
+
|
|
|
+ if (std::fabs (a_c - a_t) < std::fabs (a_s - a_t))
|
|
|
+ a_t_next = a_c;
|
|
|
+ else
|
|
|
+ a_t_next = a_s;
|
|
|
+
|
|
|
+ if (a_t > a_l)
|
|
|
+ return (std::min (a_t + 0.66 * (a_u - a_t), a_t_next));
|
|
|
+ else
|
|
|
+ return (std::max (a_t + 0.66 * (a_u - a_t), a_t_next));
|
|
|
+ }
|
|
|
+ // Case 4 in Trial Value Selection [More, Thuente 1994]
|
|
|
+ else
|
|
|
+ {
|
|
|
+ // Calculate the minimizer of the cubic that interpolates f_u, f_t, g_u and g_t
|
|
|
+ // Equation 2.4.52 [Sun, Yuan 2006]
|
|
|
+ double z = 3 * (f_t - f_u) / (a_t - a_u) - g_t - g_u;
|
|
|
+ double w = std::sqrt (z * z - g_t * g_u);
|
|
|
+ // Equation 2.4.56 [Sun, Yuan 2006]
|
|
|
+ return (a_u + (a_t - a_u) * (w - g_u - z) / (g_t - g_u + 2 * w));
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
|
+template<typename PointSource, typename PointTarget> double
|
|
|
+pclomp::NormalDistributionsTransform<PointSource, PointTarget>::computeStepLengthMT (const Eigen::Matrix<double, 6, 1> &x, Eigen::Matrix<double, 6, 1> &step_dir, double step_init, double step_max,
|
|
|
+ double step_min, double &score, Eigen::Matrix<double, 6, 1> &score_gradient, Eigen::Matrix<double, 6, 6> &hessian,
|
|
|
+ PointCloudSource &trans_cloud)
|
|
|
+{
|
|
|
+ // Set the value of phi(0), Equation 1.3 [More, Thuente 1994]
|
|
|
+ double phi_0 = -score;
|
|
|
+ // Set the value of phi'(0), Equation 1.3 [More, Thuente 1994]
|
|
|
+ double d_phi_0 = -(score_gradient.dot (step_dir));
|
|
|
+
|
|
|
+ Eigen::Matrix<double, 6, 1> x_t;
|
|
|
+
|
|
|
+ if (d_phi_0 >= 0)
|
|
|
+ {
|
|
|
+ // Not a decent direction
|
|
|
+ if (d_phi_0 == 0)
|
|
|
+ return 0;
|
|
|
+ else
|
|
|
+ {
|
|
|
+ // Reverse step direction and calculate optimal step.
|
|
|
+ d_phi_0 *= -1;
|
|
|
+ step_dir *= -1;
|
|
|
+
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ // The Search Algorithm for T(mu) [More, Thuente 1994]
|
|
|
+
|
|
|
+ int max_step_iterations = 10;
|
|
|
+ int step_iterations = 0;
|
|
|
+
|
|
|
+ // Sufficient decreace constant, Equation 1.1 [More, Thuete 1994]
|
|
|
+ double mu = 1.e-4;
|
|
|
+ // Curvature condition constant, Equation 1.2 [More, Thuete 1994]
|
|
|
+ double nu = 0.9;
|
|
|
+
|
|
|
+ // Initial endpoints of Interval I,
|
|
|
+ double a_l = 0, a_u = 0;
|
|
|
+
|
|
|
+ // Auxiliary function psi is used until I is determined ot be a closed interval, Equation 2.1 [More, Thuente 1994]
|
|
|
+ double f_l = auxilaryFunction_PsiMT (a_l, phi_0, phi_0, d_phi_0, mu);
|
|
|
+ double g_l = auxilaryFunction_dPsiMT (d_phi_0, d_phi_0, mu);
|
|
|
+
|
|
|
+ double f_u = auxilaryFunction_PsiMT (a_u, phi_0, phi_0, d_phi_0, mu);
|
|
|
+ double g_u = auxilaryFunction_dPsiMT (d_phi_0, d_phi_0, mu);
|
|
|
+
|
|
|
+ // Check used to allow More-Thuente step length calculation to be skipped by making step_min == step_max
|
|
|
+ bool interval_converged = (step_max - step_min) > 0, open_interval = true;
|
|
|
+
|
|
|
+ double a_t = step_init;
|
|
|
+ a_t = std::min (a_t, step_max);
|
|
|
+ a_t = std::max (a_t, step_min);
|
|
|
+
|
|
|
+ x_t = x + step_dir * a_t;
|
|
|
+
|
|
|
+ final_transformation_ = (Eigen::Translation<float, 3>(static_cast<float> (x_t (0)), static_cast<float> (x_t (1)), static_cast<float> (x_t (2))) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (3)), Eigen::Vector3f::UnitX ()) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (4)), Eigen::Vector3f::UnitY ()) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (5)), Eigen::Vector3f::UnitZ ())).matrix ();
|
|
|
+
|
|
|
+ // New transformed point cloud
|
|
|
+ transformPointCloud (*input_, trans_cloud, final_transformation_);
|
|
|
+
|
|
|
+ // Updates score, gradient and hessian. Hessian calculation is unessisary but testing showed that most step calculations use the
|
|
|
+ // initial step suggestion and recalculation the reusable portions of the hessian would intail more computation time.
|
|
|
+ score = computeDerivatives (score_gradient, hessian, trans_cloud, x_t, true);
|
|
|
+
|
|
|
+ // Calculate phi(alpha_t)
|
|
|
+ double phi_t = -score;
|
|
|
+ // Calculate phi'(alpha_t)
|
|
|
+ double d_phi_t = -(score_gradient.dot (step_dir));
|
|
|
+
|
|
|
+ // Calculate psi(alpha_t)
|
|
|
+ double psi_t = auxilaryFunction_PsiMT (a_t, phi_t, phi_0, d_phi_0, mu);
|
|
|
+ // Calculate psi'(alpha_t)
|
|
|
+ double d_psi_t = auxilaryFunction_dPsiMT (d_phi_t, d_phi_0, mu);
|
|
|
+
|
|
|
+ // Iterate until max number of iterations, interval convergance or a value satisfies the sufficient decrease, Equation 1.1, and curvature condition, Equation 1.2 [More, Thuente 1994]
|
|
|
+ while (!interval_converged && step_iterations < max_step_iterations && !(psi_t <= 0 /*Sufficient Decrease*/ && d_phi_t <= -nu * d_phi_0 /*Curvature Condition*/))
|
|
|
+ {
|
|
|
+ // Use auxilary function if interval I is not closed
|
|
|
+ if (open_interval)
|
|
|
+ {
|
|
|
+ a_t = trialValueSelectionMT (a_l, f_l, g_l,
|
|
|
+ a_u, f_u, g_u,
|
|
|
+ a_t, psi_t, d_psi_t);
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ a_t = trialValueSelectionMT (a_l, f_l, g_l,
|
|
|
+ a_u, f_u, g_u,
|
|
|
+ a_t, phi_t, d_phi_t);
|
|
|
+ }
|
|
|
+
|
|
|
+ a_t = std::min (a_t, step_max);
|
|
|
+ a_t = std::max (a_t, step_min);
|
|
|
+
|
|
|
+ x_t = x + step_dir * a_t;
|
|
|
+
|
|
|
+ final_transformation_ = (Eigen::Translation<float, 3> (static_cast<float> (x_t (0)), static_cast<float> (x_t (1)), static_cast<float> (x_t (2))) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (3)), Eigen::Vector3f::UnitX ()) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (4)), Eigen::Vector3f::UnitY ()) *
|
|
|
+ Eigen::AngleAxis<float> (static_cast<float> (x_t (5)), Eigen::Vector3f::UnitZ ())).matrix ();
|
|
|
+
|
|
|
+ // New transformed point cloud
|
|
|
+ // Done on final cloud to prevent wasted computation
|
|
|
+ transformPointCloud (*input_, trans_cloud, final_transformation_);
|
|
|
+
|
|
|
+ // Updates score, gradient. Values stored to prevent wasted computation.
|
|
|
+ score = computeDerivatives (score_gradient, hessian, trans_cloud, x_t, false);
|
|
|
+
|
|
|
+ // Calculate phi(alpha_t+)
|
|
|
+ phi_t = -score;
|
|
|
+ // Calculate phi'(alpha_t+)
|
|
|
+ d_phi_t = -(score_gradient.dot (step_dir));
|
|
|
+
|
|
|
+ // Calculate psi(alpha_t+)
|
|
|
+ psi_t = auxilaryFunction_PsiMT (a_t, phi_t, phi_0, d_phi_0, mu);
|
|
|
+ // Calculate psi'(alpha_t+)
|
|
|
+ d_psi_t = auxilaryFunction_dPsiMT (d_phi_t, d_phi_0, mu);
|
|
|
+
|
|
|
+ // Check if I is now a closed interval
|
|
|
+ if (open_interval && (psi_t <= 0 && d_psi_t >= 0))
|
|
|
+ {
|
|
|
+ open_interval = false;
|
|
|
+
|
|
|
+ // Converts f_l and g_l from psi to phi
|
|
|
+ f_l = f_l + phi_0 - mu * d_phi_0 * a_l;
|
|
|
+ g_l = g_l + mu * d_phi_0;
|
|
|
+
|
|
|
+ // Converts f_u and g_u from psi to phi
|
|
|
+ f_u = f_u + phi_0 - mu * d_phi_0 * a_u;
|
|
|
+ g_u = g_u + mu * d_phi_0;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (open_interval)
|
|
|
+ {
|
|
|
+ // Update interval end points using Updating Algorithm [More, Thuente 1994]
|
|
|
+ interval_converged = updateIntervalMT (a_l, f_l, g_l,
|
|
|
+ a_u, f_u, g_u,
|
|
|
+ a_t, psi_t, d_psi_t);
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ // Update interval end points using Modified Updating Algorithm [More, Thuente 1994]
|
|
|
+ interval_converged = updateIntervalMT (a_l, f_l, g_l,
|
|
|
+ a_u, f_u, g_u,
|
|
|
+ a_t, phi_t, d_phi_t);
|
|
|
+ }
|
|
|
+
|
|
|
+ step_iterations++;
|
|
|
+ }
|
|
|
+
|
|
|
+ // If inner loop was run then hessian needs to be calculated.
|
|
|
+ // Hessian is unnessisary for step length determination but gradients are required
|
|
|
+ // so derivative and transform data is stored for the next iteration.
|
|
|
+ if (step_iterations)
|
|
|
+ computeHessian (hessian, trans_cloud, x_t);
|
|
|
+
|
|
|
+ return (a_t);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+template<typename PointSource, typename PointTarget>
|
|
|
+double pclomp::NormalDistributionsTransform<PointSource, PointTarget>::calculateScore(const PointCloudSource & trans_cloud) const
|
|
|
+{
|
|
|
+ double score = 0;
|
|
|
+
|
|
|
+ for (int idx = 0; idx < trans_cloud.points.size(); idx++)
|
|
|
+ {
|
|
|
+ PointSource x_trans_pt = trans_cloud.points[idx];
|
|
|
+
|
|
|
+ // Find nieghbors (Radius search has been experimentally faster than direct neighbor checking.
|
|
|
+ std::vector<TargetGridLeafConstPtr> neighborhood;
|
|
|
+ std::vector<float> distances;
|
|
|
+ target_cells_.radiusSearch(x_trans_pt, resolution_, neighborhood, distances);
|
|
|
+
|
|
|
+ for (typename std::vector<TargetGridLeafConstPtr>::iterator neighborhood_it = neighborhood.begin(); neighborhood_it != neighborhood.end(); neighborhood_it++)
|
|
|
+ {
|
|
|
+ TargetGridLeafConstPtr cell = *neighborhood_it;
|
|
|
+
|
|
|
+ Eigen::Vector3d x_trans = Eigen::Vector3d(x_trans_pt.x, x_trans_pt.y, x_trans_pt.z);
|
|
|
+
|
|
|
+ // Denorm point, x_k' in Equations 6.12 and 6.13 [Magnusson 2009]
|
|
|
+ x_trans -= cell->getMean();
|
|
|
+ // Uses precomputed covariance for speed.
|
|
|
+ Eigen::Matrix3d c_inv = cell->getInverseCov();
|
|
|
+
|
|
|
+ // e^(-d_2/2 * (x_k - mu_k)^T Sigma_k^-1 (x_k - mu_k)) Equation 6.9 [Magnusson 2009]
|
|
|
+ double e_x_cov_x = exp(-gauss_d2_ * x_trans.dot(c_inv * x_trans) / 2);
|
|
|
+ // Calculate probability of transtormed points existance, Equation 6.9 [Magnusson 2009]
|
|
|
+ double score_inc = -gauss_d1_ * e_x_cov_x - gauss_d3_;
|
|
|
+
|
|
|
+ score += score_inc / neighborhood.size();
|
|
|
+ }
|
|
|
+ }
|
|
|
+ return (score) / static_cast<double> (trans_cloud.size());
|
|
|
+}
|
|
|
+
|
|
|
+#endif // PCL_REGISTRATION_NDT_IMPL_H_
|