Fatras/Digitization/PlanarSurfaceDriftTests.cpp

0001 // This file is part of the Acts project.
0002 //
0003 // Copyright (C) 2021 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 http://mozilla.org/MPL/2.0/.
0008
0009 #include <boost/test/data/test_case.hpp>
0010 #include <boost/test/unit_test.hpp>
0011
0012 #include "Acts/Definitions/Algebra.hpp"
0013 #include "Acts/Definitions/Tolerance.hpp"
0014 #include "Acts/Geometry/GeometryContext.hpp"
0015 #include "Acts/Surfaces/PlaneSurface.hpp"
0016 #include "Acts/Surfaces/Surface.hpp"
0017 #include "Acts/Tests/CommonHelpers/FloatComparisons.hpp"
0018 #include "ActsFatras/Digitization/PlanarSurfaceDrift.hpp"
0019
0020 #include <array>
0021 #include <memory>
0022
0023 namespace bdata = boost::unit_test::data;
0024
0025 namespace ActsFatras {
0026
0027 BOOST_AUTO_TEST_SUITE(Digitization)
0028
0029 BOOST_AUTO_TEST_CASE(PlanarSurfaceDrift) {
0030   Acts::GeometryContext geoCtx;
0031
0032   ActsFatras::PlanarSurfaceDrift psd;
0033
0034   Acts::Vector3 cPosition = Acts::Vector3(10., 50., 12.);
0035   Acts::Vector3 cNormal = Acts::Vector3(1., 1., 1.).normalized();
0036
0037   auto planeSurface =
0038       Acts::Surface::makeShared<Acts::PlaneSurface>(cPosition, cNormal);
0039
0040   double depletion = 0.250;
0041
0042   // Nominal intersection
0043   Acts::Vector3 noDrift(0., 0., 0.);
0044   Acts::Vector3 holeDrift = Acts::Vector3(0.5, 0., 1.).normalized();
0045   Acts::Vector3 chargeDrift = Acts::Vector3(0.5, 0., -1.).normalized();
0046
0047   // Intersect surface at normal direction and no drift
0048   //
0049   // -> resulting segment must have entry & exit at (0,0) local coordinates
0050   auto noDriftSegment = psd.toReadout(geoCtx, *planeSurface, depletion,
0051                                       cPosition, cNormal, noDrift);
0052
0053   CHECK_CLOSE_ABS(noDriftSegment[0].x(), 0., Acts::s_epsilon);
0054   CHECK_CLOSE_ABS(noDriftSegment[0].y(), 0., Acts::s_epsilon);
0055   CHECK_CLOSE_ABS(noDriftSegment[1].x(), 0., Acts::s_epsilon);
0056   CHECK_CLOSE_ABS(noDriftSegment[1].y(), 0., Acts::s_epsilon);
0057
0058   Acts::Vector3 particleDir = Acts::Vector3(2., 1., 1.).normalized();
0059
0060   // Intersect surface at particleDirection != normal and no drift
0061   //
0062   // -> local segment must be symmetric around (0,0)
0063   noDriftSegment = psd.toReadout(geoCtx, *planeSurface, depletion, cPosition,
0064                                  particleDir, noDrift);
0065
0066   CHECK_CLOSE_ABS(noDriftSegment[0].x(), -noDriftSegment[1].x(),
0067                   Acts::s_epsilon);
0068   CHECK_CLOSE_ABS(noDriftSegment[0].y(), -noDriftSegment[1].y(),
0069                   Acts::s_epsilon);
0070
0071   // Intersect surface at particleDirection != normal and a drift somewhat along
0072   // the normal and x
0073   //
0074   // -> local segment must not be symmetric around (0,0)
0075   // -> segment exit at pos local z remains unchanged
0076   // -> segment entry at neg local z changes in x, remains unchanged in y
0077   auto driftedSegment = psd.toReadout(geoCtx, *planeSurface, depletion,
0078                                       cPosition, particleDir, holeDrift);
0079
0080   BOOST_CHECK(std::abs(driftedSegment[0].x() - driftedSegment[1].x()) >
0081               Acts::s_epsilon);
0082   BOOST_CHECK(std::abs(driftedSegment[0].y() - driftedSegment[1].y()) >
0083               Acts::s_epsilon);
0084   CHECK_CLOSE_ABS(noDriftSegment[1].x(), driftedSegment[1].x(),
0085                   Acts::s_epsilon);
0086   CHECK_CLOSE_ABS(noDriftSegment[1].y(), driftedSegment[1].y(),
0087                   Acts::s_epsilon);
0088   BOOST_CHECK(std::abs(driftedSegment[0].x() - noDriftSegment[0].x()) >
0089               Acts::s_epsilon);
0090   CHECK_CLOSE_ABS(driftedSegment[0].y(), noDriftSegment[0].y(),
0091                   Acts::s_epsilon);
0092
0093   // Intersect surface at particleDirection != normal and a drift somewhat
0094   // opposite the normal and y
0095   //
0096   // -> local segment must not be symmetric around (0,0)
0097   // -> segment entry at neg local z remains unchanged
0098   // -> segment exit at pos local z changes in x, remains unchanged in y
0099   driftedSegment = psd.toReadout(geoCtx, *planeSurface, depletion, cPosition,
0100                                  particleDir, chargeDrift);
0101
0102   BOOST_CHECK(std::abs(driftedSegment[0].x() - driftedSegment[1].x()) >
0103               Acts::s_epsilon);
0104   BOOST_CHECK(std::abs(driftedSegment[0].y() - driftedSegment[1].y()) >
0105               Acts::s_epsilon);
0106   CHECK_CLOSE_ABS(noDriftSegment[0].x(), driftedSegment[0].x(),
0107                   Acts::s_epsilon);
0108   CHECK_CLOSE_ABS(noDriftSegment[0].y(), driftedSegment[0].y(),
0109                   Acts::s_epsilon);
0110   BOOST_CHECK(std::abs(driftedSegment[1].x() - noDriftSegment[1].x()) >
0111               Acts::s_epsilon);
0112   CHECK_CLOSE_ABS(driftedSegment[1].y(), noDriftSegment[1].y(),
0113                   Acts::s_epsilon);
0114 }
0115
0116 BOOST_AUTO_TEST_SUITE_END()
0117
0118 }  // namespace ActsFatras