Surfaces/detail/MergeHelper.cpp

0001 // This file is part of the ACTS project.
0002 //
0003 // Copyright (C) 2016 CERN for the benefit of the ACTS project
0004 //
0005 // This Source Code Form is subject to the terms of the Mozilla Public
0006 // License, v. 2.0. If a copy of the MPL was not distributed with this
0007 // file, You can obtain one at https://mozilla.org/MPL/2.0/.
0008
0009 #include "Acts/Surfaces/detail/MergeHelper.hpp"
0010
0011 #include "Acts/Definitions/Units.hpp"
0012 #include "Acts/Utilities/detail/periodic.hpp"
0013
0014 #include <numbers>
0015
0016 namespace Acts::detail {
0017
0018 std::tuple<double, double, bool> mergedPhiSector(double hlPhi1, double avgPhi1,
0019                                                  double hlPhi2, double avgPhi2,
0020                                                  const Logger& logger,
0021                                                  double tolerance) {
0022   using namespace UnitLiterals;
0023
0024   if (std::abs(hlPhi1 - std::numbers::pi / 2.) < tolerance &&
0025       std::abs(hlPhi2 - std::numbers::pi / 2.) < tolerance) {
0026     ACTS_VERBOSE("Both phi sectors cover a half circle");
0027
0028     ACTS_VERBOSE("-> distance between sectors: " << detail::difference_periodic(
0029                                                         avgPhi1, avgPhi2,
0030                                                         2 * std::numbers::pi) /
0031                                                         1_degree);
0032
0033     if (std::abs(std::abs(detail::difference_periodic(avgPhi1, avgPhi2,
0034                                                       2 * std::numbers::pi)) -
0035                  std::numbers::pi) > tolerance) {
0036       throw std::invalid_argument(
0037           "Phi sectors cover half a circle but are not opposite");
0038     }
0039
0040     double newAvgPhi = detail::radian_sym(avgPhi1 + std::numbers::pi / 2.);
0041     double newHlPhi = std::numbers::pi;
0042     ACTS_VERBOSE("merged: ["
0043                  << detail::radian_sym(newAvgPhi - newHlPhi) / 1_degree << ", "
0044                  << detail::radian_sym(newAvgPhi + newHlPhi) / 1_degree
0045                  << "] ~> " << newAvgPhi / 1_degree << " +- "
0046                  << newHlPhi / 1_degree);
0047     return {newHlPhi, newAvgPhi, false};
0048   }
0049
0050   double minPhi1 = detail::radian_sym(-hlPhi1 + avgPhi1);
0051   double maxPhi1 = detail::radian_sym(hlPhi1 + avgPhi1);
0052
0053   ACTS_VERBOSE("one: [" << minPhi1 / 1_degree << ", " << maxPhi1 / 1_degree
0054                         << "] ~> " << avgPhi1 / 1_degree << " +- "
0055                         << hlPhi1 / 1_degree);
0056
0057   double maxPhi2 = detail::radian_sym(hlPhi2 + avgPhi2);
0058   double minPhi2 = detail::radian_sym(-hlPhi2 + avgPhi2);
0059
0060   ACTS_VERBOSE("two: [" << minPhi2 / 1_degree << ", " << maxPhi2 / 1_degree
0061                         << "] ~> " << avgPhi2 / 1_degree << " +- "
0062                         << hlPhi2 / 1_degree);
0063
0064   ACTS_VERBOSE("Checking for CCW or CW ordering");
0065   auto same = [tolerance](double a, double b) {
0066     return std::abs(a - b) < tolerance;
0067   };
0068
0069   double newMaxPhi{}, newMinPhi{};
0070   double newHlPhi = hlPhi1 + hlPhi2;
0071
0072   bool reversed = false;
0073   if (same(minPhi1, maxPhi2)) {
0074     ACTS_VERBOSE("-> CCW ordering: one is 'right' of two");
0075
0076     newMinPhi = minPhi2;
0077     newMaxPhi = maxPhi1;
0078   } else if (same(maxPhi1, minPhi2)) {
0079     ACTS_VERBOSE("-> CW ordering: one is 'left' of two");
0080     newMinPhi = minPhi1;
0081     newMaxPhi = maxPhi2;
0082     reversed = true;
0083   } else {
0084     ACTS_ERROR("Phi ranges are incompatible");
0085     throw std::invalid_argument("Phi ranges are incompatible");
0086   }
0087
0088   double newAvgPhi = detail::radian_sym(newMinPhi + newHlPhi);
0089
0090   ACTS_VERBOSE("merged: [" << newMinPhi / 1_degree << ", "
0091                            << newMaxPhi / 1_degree << "] ~> "
0092                            << newAvgPhi / 1_degree << " +- "
0093                            << newHlPhi / 1_degree);
0094
0095   return {newHlPhi, newAvgPhi, reversed};
0096 }
0097
0098 }  // namespace Acts::detail