alongstep/detail/AlongStepNeutralImpl.hh

0001 //----------------------------------*-C++-*----------------------------------//
0002 // Copyright 2022-2024 UT-Battelle, LLC, and other Celeritas developers.
0003 // See the top-level COPYRIGHT file for details.
0004 // SPDX-License-Identifier: (Apache-2.0 OR MIT)
0005 //---------------------------------------------------------------------------//
0006 //! \file celeritas/global/alongstep/detail/AlongStepNeutralImpl.hh
0007 //---------------------------------------------------------------------------//
0008 #pragma once
0009
0010 #include "corecel/Assert.hh"
0011 #include "corecel/Macros.hh"
0012 #include "corecel/Types.hh"
0013 #include "corecel/math/Quantity.hh"
0014
0015 #include "../AlongStep.hh"
0016
0017 namespace celeritas
0018 {
0019 //---------------------------------------------------------------------------//
0020 class CoreTrackView;
0021
0022 namespace detail
0023 {
0024 //---------------------------------------------------------------------------//
0025 /*!
0026  * Helper class for along-step kernel when no MSC is in use.
0027  */
0028 struct NoMsc
0029 {
0030     //! MSC never applies to the current track
0031     CELER_FUNCTION bool
0032     is_applicable(CoreTrackView const&, real_type step) const
0033     {
0034         CELER_ASSERT(step > 0);
0035         return false;
0036     }
0037
0038     //! No updates needed to the physical and geometric step lengths
0039     CELER_FUNCTION void limit_step(CoreTrackView const&) const {}
0040
0041     //! MSC is never applied
0042     CELER_FUNCTION void apply_step(CoreTrackView const&) const {}
0043 };
0044
0045 //---------------------------------------------------------------------------//
0046 /*!
0047  * Class that returns zero energy loss.
0048  */
0049 struct NoELoss
0050 {
0051     //! This calculator never returns energy loss
0052     CELER_CONSTEXPR_FUNCTION bool is_applicable(CoreTrackView const&)
0053     {
0054         return false;
0055     }
0056
0057     //! No energy loss
0058     CELER_FUNCTION auto
0059     calc_eloss(CoreTrackView const&, real_type, bool) const -> decltype(auto)
0060     {
0061         return zero_quantity();
0062     }
0063
0064     //! No slowing down
0065     static CELER_CONSTEXPR_FUNCTION bool imprecise_range() { return false; }
0066 };
0067
0068 //---------------------------------------------------------------------------//
0069 }  // namespace detail
0070 }  // namespace celeritas