CbmStsMC.cxx

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/* Copyright (C) 2006-2020 GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
   SPDX-License-Identifier: GPL-3.0-only
   Authors: Volker Friese, Denis Bertini [committer], Florian Uhlig */
 
#include "CbmStsMC.h"
 
#include "CbmGeometryUtils.h"
#include "CbmStack.h"
#include "CbmStsElement.h"
#include "CbmStsPoint.h"
#include "CbmStsSetup.h"
 
#include <Logger.h>
 
#include "TGeoBBox.h"
#include "TGeoManager.h"
#include "TGeoPhysicalNode.h"
#include "TKey.h"
#include "TParticle.h"
#include "TVector3.h"
#include "TVirtualMC.h"
#include <TFile.h>
 
using std::map;
using std::pair;
 
// -----   Constructor   ---------------------------------------------------
CbmStsMC::CbmStsMC(Bool_t active, const char* name)
  : FairDetector(name, active, ToIntegralType(ECbmModuleId::kSts))
  , fStatusIn()
  , fStatusOut()
  , fEloss(0.)
  , fAddressMap()
  , fStsPoints(NULL)
  , fSetup(NULL)
  , fCombiTrans(NULL)
  , fProcessNeutrals(kFALSE)
{
}
// -------------------------------------------------------------------------
 
 
// -----   Destructor   ----------------------------------------------------
CbmStsMC::~CbmStsMC()
{
  if (fStsPoints) {
    fStsPoints->Delete();
    delete fStsPoints;
  }
  if (fCombiTrans) { delete fCombiTrans; }
}
// -------------------------------------------------------------------------
 
 
// -----  ConstructGeometry  -----------------------------------------------
void CbmStsMC::ConstructGeometry()
{
 
  TString fileName = GetGeometryFileName();
 
  // --- Only ROOT geometries are supported
  if (!fileName.EndsWith(".root")) {
    LOG(fatal) << GetName() << ": Geometry format of file " << fileName.Data() << " not supported.";
  }
  ConstructRootGeometry();
}
// -------------------------------------------------------------------------
 
 
// -----   End of event action   -------------------------------------------
void CbmStsMC::EndOfEvent()
{
  Print();  // Status output
  Reset();  // Reset the track status parameters
}
// -------------------------------------------------------------------------
 
 
// -----   Initialise   ----------------------------------------------------
void CbmStsMC::Initialize()
{
 
  // --- Instantiate the output array
  fStsPoints = new TClonesArray("CbmStsPoint");
 
  // --- Get the CbmStsSetup instance and construct a map from full path
  // --- to address for each sensor. This is needed to store the unique x
  // --- address of the activated sensor in the CbmStsPoint class.
  // --- Unfortunately, the full geometry path (string) is the only way
  // --- to unambiguously identify the current active node during the
  // --- transport. It may seem that looking up a string in a map is not
  // --- efficient. I checked however, that the performance penalty is very
  // --- small.
  fAddressMap.clear();
  fSetup = CbmStsSetup::Instance();
  fSetup->Init();
  Int_t nUnits = fSetup->GetNofDaughters();
  for (Int_t iUnit = 0; iUnit < nUnits; iUnit++) {
    CbmStsElement* unit = fSetup->GetDaughter(iUnit);
    Int_t nLadd         = unit->GetNofDaughters();
    for (Int_t iLadd = 0; iLadd < nLadd; iLadd++) {
      CbmStsElement* ladd = unit->GetDaughter(iLadd);
      Int_t nHlad         = ladd->GetNofDaughters();
      for (Int_t iHlad = 0; iHlad < nHlad; iHlad++) {
        CbmStsElement* hlad = ladd->GetDaughter(iHlad);
        Int_t nModu         = hlad->GetNofDaughters();
        for (Int_t iModu = 0; iModu < nModu; iModu++) {
          CbmStsElement* modu = hlad->GetDaughter(iModu);
          Int_t nSens         = modu->GetNofDaughters();
          for (Int_t iSens = 0; iSens < nSens; iSens++) {
            CbmStsElement* sensor = modu->GetDaughter(iSens);
            TString path          = sensor->GetPnode()->GetName();
            if (!path.BeginsWith("/")) path.Prepend("/");
            pair<TString, Int_t> a(path, sensor->GetAddress());
            fAddressMap.insert(a);
            TString test = sensor->GetPnode()->GetName();
          }
        }
      }
    }
  }
  LOG(info) << fName << ": Address map initialised with " << Int_t(fAddressMap.size()) << " sensors. ";
 
  // --- Call the Initialise method of the mother class
  FairDetector::Initialize();
}
// -------------------------------------------------------------------------
 
 
// -----   ProcessHits  ----------------------------------------------------
Bool_t CbmStsMC::ProcessHits(FairVolume* /*vol*/)
{
 
  // --- If this is the first step for the track in the sensor:
  //     Reset energy loss and store track parameters
  if (gMC->IsTrackEntering()) {
    fEloss = 0.;
    fStatusIn.Reset();
    fStatusOut.Reset();
    SetStatus(fStatusIn);
  }
 
  // --- For all steps within active volume: sum up differential energy loss
  fEloss += gMC->Edep();
 
 
  // --- If track is leaving: get track parameters and create CbmstsPoint
  if (gMC->IsTrackExiting() || gMC->IsTrackStop() || gMC->IsTrackDisappeared()) {
 
    SetStatus(fStatusOut);
 
    // --- No action if no energy loss (neutral particles)
    if (fEloss == 0. && (!fProcessNeutrals)) return kFALSE;
 
    // --- Add a StsPoint to the output array. Increment stack counter.
    CreatePoint();
 
    // --- Increment number of StsPoints for this track
    CbmStack* stack = (CbmStack*) gMC->GetStack();
    stack->AddPoint(ECbmModuleId::kSts);
 
  }  //? track is exiting or stopped
 
 
  return kTRUE;
}
// -------------------------------------------------------------------------
 
 
// -----   Reset output array and track status   ---------------------------
void CbmStsMC::Reset()
{
  fStsPoints->Delete();
  fStatusIn.Reset();
  fStatusOut.Reset();
  fEloss = 0.;
}
// -------------------------------------------------------------------------
 
 
// -----   Screen log   ----------------------------------------------------
void CbmStsMC::Print(Option_t* /*opt*/) const
{
  //Int_t nHits = fStsPoints->GetEntriesFast();
  LOG(info) << fName << ": " << fStsPoints->GetEntriesFast() << " points registered in this event.";
}
// -------------------------------------------------------------------------
 
 
// =========================================================================
// Private methods
// =========================================================================
 
 
// -----   Create STS point   ----------------------------------------------
CbmStsPoint* CbmStsMC::CreatePoint()
{
 
  // --- Check detector address
  if (fStatusIn.fAddress != fStatusOut.fAddress) {
    LOG(error) << GetName() << ": inconsistent detector addresses " << fStatusIn.fAddress << " " << fStatusOut.fAddress;
    return NULL;
  }
 
  // --- Check track Id
  if (fStatusIn.fTrackId != fStatusOut.fTrackId) {
    LOG(error) << GetName() << ": inconsistent track Id " << fStatusIn.fTrackId << " " << fStatusOut.fTrackId;
    return NULL;
  }
 
  // --- Check track PID
  if (fStatusIn.fPid != fStatusOut.fPid) {
    LOG(error) << GetName() << ": inconsistent track PID " << fStatusIn.fPid << " " << fStatusOut.fPid;
    return NULL;
  }
 
  // --- Entry position and momentum
  TVector3 posIn(fStatusIn.fX, fStatusIn.fY, fStatusIn.fZ);
  TVector3 momIn(fStatusIn.fPx, fStatusIn.fPy, fStatusIn.fPz);
 
  // --- Exit position and momentum
  TVector3 posOut(fStatusOut.fX, fStatusOut.fY, fStatusOut.fZ);
  TVector3 momOut(fStatusOut.fPx, fStatusOut.fPy, fStatusOut.fPz);
 
  // --- Time and track length (average between in and out)
  Double_t time   = 0.5 * (fStatusIn.fTime + fStatusOut.fTime);
  Double_t length = 0.5 * (fStatusIn.fLength + fStatusOut.fLength);
 
  // --- Flag for entry/exit
  Int_t flag = 0;
  if (fStatusIn.fFlag) flag += 1;   // first coordinate is entry step
  if (fStatusOut.fFlag) flag += 2;  // second coordinate is exit step
 
  // --- Debug output
  LOG(debug2) << GetName() << ": Creating point from track " << fStatusIn.fTrackId << " in sensor "
              << fStatusIn.fAddress << ", position (" << posIn.X() << ", " << posIn.Y() << ", " << posIn.Z()
              << "), energy loss " << fEloss;
 
  // --- Add new point to output array
  Int_t newIndex = fStsPoints->GetEntriesFast();
  return new ((*fStsPoints)[fStsPoints->GetEntriesFast()])
    CbmStsPoint(fStatusIn.fTrackId, fStatusIn.fAddress, posIn, posOut, momIn, momOut, time, length, fEloss,
                fStatusIn.fPid, 0, newIndex, flag);
}
// -------------------------------------------------------------------------
 
 
// -----   Set the current track status   ----------------------------------
void CbmStsMC::SetStatus(CbmStsTrackStatus& status)
{
 
  // --- Check for TVirtualMC and TGeomanager
  if (!(gMC && gGeoManager)) {
    LOG(error) << fName << ": No TVirtualMC or TGeoManager instance!";
    return;
  }
 
  // --- Address of current sensor
  // --- Use the geometry path from TVirtualMC; cannot rely on
  // --- TGeoManager here.
  TString path = gMC->CurrentVolPath();
  auto it      = fAddressMap.find(path);
  if (it == fAddressMap.end()) {
    LOG(fatal) << fName << ": Path not found in address map! " << gGeoManager->GetPath();
    status.fAddress = 0;
  }
  else
    status.fAddress = it->second;
 
  // --- Index and PID of current track
  status.fTrackId = gMC->GetStack()->GetCurrentTrackNumber();
  status.fPid     = gMC->GetStack()->GetCurrentTrack()->GetPdgCode();
 
  // --- Position
  gMC->TrackPosition(status.fX, status.fY, status.fZ);
 
  // --- Momentum
  Double_t dummy;
  gMC->TrackMomentum(status.fPx, status.fPy, status.fPz, dummy);
 
  // --- Time and track length
  status.fTime   = gMC->TrackTime() * 1.e9;  // conversion into ns
  status.fLength = gMC->TrackLength();
 
  // --- Status flag (entry/exit or new/stopped/disappeared)
  if (gMC->IsTrackEntering()) {
    if (gMC->IsNewTrack()) status.fFlag = kFALSE;  // Track created in sensor
    else
      status.fFlag = kTRUE;  // Track entering
  }
  else {  // exiting or stopped or disappeared
    if (gMC->IsTrackDisappeared() || gMC->IsTrackStop())
      status.fFlag = kFALSE;  // Track stopped or disappeared in sensor
    else
      status.fFlag = kTRUE;  // Track exiting
  }
}
// -------------------------------------------------------------------------
 
 
//__________________________________________________________________________
void CbmStsMC::ConstructRootGeometry(TGeoMatrix*)
{
  if (Cbm::GeometryUtils::IsNewGeometryFile(fgeoName)) {
    LOG(info) << "Importing STS geometry from ROOT file " << fgeoName.Data();
    Cbm::GeometryUtils::ImportRootGeometry(fgeoName, this, fCombiTrans);
  }
  else {
    LOG(info) << "Constructing STS geometry from ROOT file " << fgeoName.Data();
    FairModule::ConstructRootGeometry();
  }
}
 
ClassImp(CbmStsMC)