/data/refman/pasoursint/CMSSW_5_3_3/src/SimG4Core/MagneticField/src/FieldBuilder.cc

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// #include "DetectorDescription/Core/interface/DDLogicalPart.h"

#include "MagneticField/Engine/interface/MagneticField.h"
#include "MagneticField/Records/interface/IdealMagneticFieldRecord.h"

#include "FWCore/Framework/interface/ESHandle.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"

#include "SimG4Core/MagneticField/interface/FieldBuilder.h"
#include "SimG4Core/MagneticField/interface/Field.h"
#include "SimG4Core/MagneticField/interface/FieldStepper.h"
#include "SimG4Core/MagneticField/interface/G4MonopoleEquation.hh"
#include "SimG4Core/Notification/interface/SimG4Exception.h"

/*
#include "DetectorDescription/Parser/interface/DDLConfiguration.h"
#include "DetectorDescription/Base/interface/DDException.h"
#include "DetectorDescription/Algorithm/src/AlgoInit.h"
*/

#include "G4Mag_UsualEqRhs.hh"
#include "G4ClassicalRK4.hh"
#include "G4PropagatorInField.hh"
#include "G4FieldManager.hh"
#include "G4TransportationManager.hh"
#include "G4ChordFinder.hh"
#include "G4UniformMagField.hh"

#include "SimG4Core/MagneticField/interface/LocalFieldManager.h"

#include "G4LogicalVolumeStore.hh"

using namespace sim;

FieldBuilder::FieldBuilder(const MagneticField * f, 
                           const edm::ParameterSet & p) 
   : theField( new Field(f,p.getParameter<double>("delta"))), 
     theFieldEquation(new G4Mag_UsualEqRhs(theField.get())),
     theTopVolume(0), fChordFinder(0), fChordFinderMonopole(0),
     fieldValue(0.), minStep(0.), dChord(0.), dOneStep(0.),
     dIntersection(0.), dIntersectionAndOneStep(0.), 
     maxLoopCount(0), minEpsilonStep(0.), maxEpsilonStep(0.), 
     thePSet(p) {

  theField->fieldEquation(theFieldEquation);
}


void FieldBuilder::build( G4FieldManager* fM, G4PropagatorInField* fP) {
    
  edm::ParameterSet thePSetForGMFM =
    thePSet.getParameter<edm::ParameterSet>("ConfGlobalMFM");

  std::string volName = thePSetForGMFM.getParameter< std::string >("Volume");
  
  edm::ParameterSet volPSet =
    thePSetForGMFM.getParameter< edm::ParameterSet >( volName );
    
  configureForVolume( volName, volPSet, fM, fP );
    
  // configure( "MagneticFieldType", fM, fP ) ;

  if ( thePSet.getParameter<bool>("UseLocalMagFieldManager") )  {

    edm::ParameterSet defpset ;
    edm::ParameterSet thePSetForLMFM = 
      thePSet.getUntrackedParameter<edm::ParameterSet>("ConfLocalMFM", defpset);
    //
    // Patology !!! LocalFM requested but configuration not given ! 
    // In principal, need to throw an exception
    //
    if ( thePSetForLMFM == defpset )  {
      std::cout << " Patology ! Local Mag.Field Manager requested but config not given !\n";
      return ;
    }
       
    std::vector<std::string> ListOfVolumes = 
      thePSetForLMFM.getParameter< std::vector<std::string> >("ListOfVolumes");
          
    // creating Local Mag.Field Manager
    for (unsigned int i = 0; i < ListOfVolumes.size(); ++ i )   {
      volPSet = thePSetForLMFM.getParameter< edm::ParameterSet >(ListOfVolumes[i]);
      G4FieldManager* fAltM = new G4FieldManager() ;
      configureForVolume( ListOfVolumes[i], volPSet, fAltM ) ;
      //configureLocalFM( ListOfVolumes[i], fAltM ) ;
      LocalFieldManager* fLM = new LocalFieldManager( theField.get(), fM, fAltM ) ;
      fLM->SetVerbosity(thePSet.getUntrackedParameter<bool>("Verbosity",false));
      theTopVolume->SetFieldManager( fLM, true ) ;
    }
  }
  return ;
 
}

void FieldBuilder::configureForVolume( const std::string& volName,
                                       edm::ParameterSet& volPSet,
                                       G4FieldManager * fM,
                                       G4PropagatorInField * fP ) {

  G4LogicalVolumeStore* theStore = G4LogicalVolumeStore::GetInstance();
  for (unsigned int i=0; i<(*theStore).size(); ++i ) {
    std::string curVolName = ((*theStore)[i])->GetName();
    if ( curVolName == volName ) {
      theTopVolume = (*theStore)[i] ;
    }
  }

  fieldType     = volPSet.getParameter<std::string>("Type") ;
  stepper       = volPSet.getParameter<std::string>("Stepper") ;
  edm::ParameterSet stpPSet = 
    volPSet.getParameter<edm::ParameterSet>(stepper) ;
  minStep       = stpPSet.getParameter<double>("MinStep") ;
  dChord        = stpPSet.getParameter<double>("DeltaChord") ;
  dOneStep      = stpPSet.getParameter<double>("DeltaOneStep") ;
  dIntersection = stpPSet.getParameter<double>("DeltaIntersection") ;
  dIntersectionAndOneStep = stpPSet.getUntrackedParameter<double>("DeltaIntersectionAndOneStep",-1.);
  maxLoopCount = stpPSet.getUntrackedParameter<double>("MaximumLoopCounts",1000);
  minEpsilonStep = stpPSet.getUntrackedParameter<double>("MinimumEpsilonStep",0.00001);
  maxEpsilonStep = stpPSet.getUntrackedParameter<double>("MaximumEpsilonStep",0.01);
   
  if (fM!=0) configureFieldManager(fM);
  if (fP!=0) configurePropagatorInField(fP);    

  return;

}

G4LogicalVolume * FieldBuilder::fieldTopVolume() { return theTopVolume; }

void FieldBuilder::setStepperAndChordFinder(G4FieldManager * fM, int val) {

  if (fM != 0) {
    if (val == 0) {
      if (fChordFinder != 0) fM->SetChordFinder(fChordFinder);
    } else {
      fChordFinder = fM->GetChordFinder();
      if (fChordFinderMonopole != 0) fM->SetChordFinder(fChordFinderMonopole);
    }
  }
}

 
void FieldBuilder::configureFieldManager(G4FieldManager * fM) {

  if (fM!=0) {
    fM->SetDetectorField(theField.get());
    FieldStepper * theStepper = new FieldStepper(theField->fieldEquation());
    theStepper->select(stepper);
    G4ChordFinder * CF = new G4ChordFinder(theField.get(),minStep,theStepper);
    CF->SetDeltaChord(dChord);
    fM->SetChordFinder(CF);
    fM->SetDeltaOneStep(dOneStep);
    fM->SetDeltaIntersection(dIntersection);
    if (dIntersectionAndOneStep != -1.) 
      fM->SetAccuraciesWithDeltaOneStep(dIntersectionAndOneStep);
  }
  if (fChordFinderMonopole == 0) {
    G4MonopoleEquation* fMonopoleEquation = new G4MonopoleEquation(theField.get());
    G4MagIntegratorStepper* theStepper = new G4ClassicalRK4(fMonopoleEquation,8);
    fChordFinderMonopole = new G4ChordFinder(theField.get(),minStep,theStepper);
    fChordFinderMonopole->SetDeltaChord(dChord);
  }
}

void FieldBuilder::configurePropagatorInField(G4PropagatorInField * fP) {
  if (fP==0) return;
  fP->SetMaxLoopCount(int(maxLoopCount));
  fP->SetMinimumEpsilonStep(minEpsilonStep);
  fP->SetMaximumEpsilonStep(maxEpsilonStep);
  fP->SetVerboseLevel(0);
  return;
}