ext/detail/TrackProcessor.hh

0001 //------------------------------- -*- C++ -*- -------------------------------//
0002 // Copyright Celeritas contributors: see top-level COPYRIGHT file for details
0003 // SPDX-License-Identifier: (Apache-2.0 OR MIT)
0004 //---------------------------------------------------------------------------//
0005 //! \file celeritas/ext/detail/TrackProcessor.hh
0006 //---------------------------------------------------------------------------//
0007 #pragma once
0008
0009 #include <memory>
0010 #include <vector>
0011
0012 #include "corecel/Macros.hh"
0013 #include "celeritas/Types.hh"
0014
0015 class G4ParticleDefinition;
0016 class G4Step;
0017 class G4Track;
0018 class G4VProcess;
0019 class G4VUserTrackInformation;
0020
0021 namespace celeritas
0022 {
0023 namespace detail
0024 {
0025 //---------------------------------------------------------------------------//
0026 /*!
0027  * Manage track information for reconstruction.
0028  *
0029  * This class handles the bookkeeping of Geant4 track information needed
0030  * to reconstruct tracks during hit processing. It maintains mappings between
0031  * Celeritas PrimaryID and Geant4 track data.
0032  *
0033  */
0034 class TrackProcessor
0035 {
0036   public:
0037     //!@{
0038     //! \name Type aliases
0039     using VecParticle = std::vector<G4ParticleDefinition const*>;
0040     //!@}
0041
0042   public:
0043     // Construct with particle definitions for track reconstruction
0044     explicit TrackProcessor(VecParticle const&);
0045
0046     ~TrackProcessor();
0047     CELER_DEFAULT_MOVE_DELETE_COPY(TrackProcessor);
0048
0049     // Clear G4Track reconstruction data
0050     void end_event();
0051
0052     // Register mapping from Celeritas PrimaryID to Geant4 TrackID
0053     [[nodiscard]] PrimaryId register_primary(G4Track&);
0054
0055     // Restore track information for given primary and particle IDs
0056     G4Track& restore_track(ParticleId, PrimaryId) const;
0057
0058     // Get the owned step
0059     G4Step& step() { return *step_; }
0060
0061   private:
0062     //! Data needed to reconstruct a G4Track from Celeritas transport
0063     class GeantTrackReconstructionData
0064     {
0065       public:
0066         //! Save the G4Track reconstruction data
0067         explicit GeantTrackReconstructionData(G4Track&);
0068         //! Whether the data is valid
0069         explicit operator bool() const { return track_id_ >= 0; }
0070         //! Restore the G4Track from the reconstruction data
0071         void restore_track(G4Track&) const;
0072
0073       private:
0074         //! Original Geant4 track ID
0075         int track_id_{-1};
0076         //! Original Geant4 parent ID
0077         int parent_id_{0};
0078         //! User track information
0079         std::unique_ptr<G4VUserTrackInformation> user_info_;
0080         //! Process that created the track
0081         G4VProcess const* creator_process_{nullptr};
0082     };
0083
0084     //! G4Track reconstruction data indexed by Celeritas PrimaryID
0085     std::vector<GeantTrackReconstructionData> g4_track_data_;
0086     //! Tracks for each particle type
0087     std::vector<std::unique_ptr<G4Track>> tracks_;
0088     //! Owned step object
0089     std::unique_ptr<G4Step> step_;
0090 };
0091
0092 //---------------------------------------------------------------------------//
0093 }  // namespace detail
0094 }  // namespace celeritas