G4PathFinder Class Reference

#include <G4PathFinder.hh>

Public Member Functions
G4double	ComputeStep (const G4FieldTrack &pFieldTrack, G4double pCurrentProposedStepLength, G4int navigatorId, G4int stepNo, G4double &pNewSafety, ELimited &limitedStep, G4FieldTrack &EndState, G4VPhysicalVolume *currentVolume)
void	Locate (const G4ThreeVector &position, const G4ThreeVector &direction, G4bool relativeSearch=true)
void	ReLocate (const G4ThreeVector &position)
void	PrepareNewTrack (const G4ThreeVector &position, const G4ThreeVector &direction, G4VPhysicalVolume *massStartVol=0)
G4TouchableHandle	CreateTouchableHandle (G4int navId) const
G4VPhysicalVolume *	GetLocatedVolume (G4int navId) const
void	SetChargeMomentumMass (G4double charge, G4double momentum, G4double pMass)
G4bool	IsParticleLooping () const
G4double	GetCurrentSafety () const
G4double	GetMinimumStep () const
unsigned int	GetNumberGeometriesLimitingStep () const
G4double	ComputeSafety (const G4ThreeVector &globalPoint)
G4double	ObtainSafety (G4int navId, G4ThreeVector &globalCenterPoint)
void	EnableParallelNavigation (G4bool enableChoice=true)
G4int	SetVerboseLevel (G4int lev=-1)
G4int	GetMaxLoopCount () const
void	SetMaxLoopCount (G4int new_max)
void	MovePoint ()
G4double	LastPreSafety (G4int navId, G4ThreeVector &globalCenterPoint, G4double &minSafety)
void	PushPostSafetyToPreSafety ()
G4String &	LimitedString (ELimited lim)
Static Public Member Functions
static G4PathFinder *	GetInstance ()
Protected Member Functions
G4double	DoNextLinearStep (const G4FieldTrack &FieldTrack, G4double proposedStepLength)
G4double	DoNextCurvedStep (const G4FieldTrack &FieldTrack, G4double proposedStepLength, G4VPhysicalVolume *pCurrentPhysVolume)
void	WhichLimited ()
void	PrintLimited ()
G4bool	UseSafetyForOptimization (G4bool)
void	ReportMove (const G4ThreeVector &OldV, const G4ThreeVector &NewV, const G4String &Quantity) const
	G4PathFinder ()
	~G4PathFinder ()
G4Navigator *	GetNavigator (G4int n) const

---

Detailed Description

Definition at line 61 of file G4PathFinder.hh.

---

Constructor & Destructor Documentation

G4PathFinder::G4PathFinder

(

)

[protected]

Definition at line 70 of file G4PathFinder.cc.

References G4GeometryTolerance::GetInstance(), G4TransportationManager::GetPropagatorInField(), G4GeometryTolerance::GetSurfaceTolerance(), G4TransportationManager::GetTransportationManager(), and kUndefLimited.

  : fEndState( G4ThreeVector(), G4ThreeVector(), 0., 0., 0., 0., 0.),
    fFieldExertedForce(false),
    fRelocatedPoint(true),
    fLastStepNo(-1), fCurrentStepNo(-1),
    fVerboseLevel(0)
{
   fpMultiNavigator= new G4MultiNavigator(); 

   fpTransportManager= G4TransportationManager::GetTransportationManager();
   fpFieldPropagator = fpTransportManager->GetPropagatorInField();

   kCarTolerance = G4GeometryTolerance::GetInstance()->GetSurfaceTolerance();

   fNoActiveNavigators= 0; 
   G4ThreeVector  Big3Vector( kInfinity, kInfinity, kInfinity );
   fLastLocatedPosition= Big3Vector;
   fSafetyLocation= Big3Vector; 
   fPreSafetyLocation= Big3Vector;
   fPreStepLocation= Big3Vector;

   fPreSafetyMinValue=  -1.0; 
   fMinSafety_PreStepPt= -1.0; 
   fMinSafety_atSafLocation= -1.0; 
   fMinStep=   -1.0;
   fTrueMinStep= -1.0;
   fPreStepCenterRenewed= false;
   fNewTrack= false; 
   fNoGeometriesLimiting= 0; 

   for( register int num=0; num< fMaxNav; ++num )
   {
      fpNavigator[num] =  0;   
      fLimitTruth[num] = false;
      fLimitedStep[num] = kUndefLimited;
      fCurrentStepSize[num] = -1.0; 
      fLocatedVolume[num] = 0;
      fPreSafetyValues[num]= -1.0; 
      fCurrentPreStepSafety[num] = -1.0;
      fNewSafetyComputed[num]= -1.0; 
   }
}

G4PathFinder::~G4PathFinder

(

)

[protected]

Definition at line 116 of file G4PathFinder.cc.

{
   delete fpMultiNavigator; 
}

---

Member Function Documentation

G4double G4PathFinder::ComputeSafety

(

const G4ThreeVector &

globalPoint

)

Definition at line 732 of file G4PathFinder.cc.

References G4cout, G4endl, and G4TransportationManager::GetActiveNavigatorsIterator().

Referenced by G4CoupledTransportation::AlongStepGetPhysicalInteractionLength(), G4SafetyHelper::ComputeSafety(), DoNextCurvedStep(), and ReLocate().

{
    // Recompute safety for the relevant point

   G4double minSafety= kInfinity; 
  
   std::vector<G4Navigator*>::iterator pNavigatorIter;
   pNavigatorIter= fpTransportManager->GetActiveNavigatorsIterator();

   for( register G4int num=0; num<fNoActiveNavigators; ++pNavigatorIter,++num )
   {
      G4double safety = (*pNavigatorIter)->ComputeSafety( position,true );
      if( safety < minSafety ) { minSafety = safety; } 
      fNewSafetyComputed[num]= safety;
   } 

   fSafetyLocation= position;
   fMinSafety_atSafLocation = minSafety;

#ifdef G4DEBUG_PATHFINDER
   if( fVerboseLevel > 1 )
   { 
     G4cout << " G4PathFinder::ComputeSafety - returns " 
            << minSafety << " at location " << position << G4endl;
   }
#endif
   return minSafety; 
}

G4double G4PathFinder::ComputeStep	(	const G4FieldTrack &	pFieldTrack,
		G4double	pCurrentProposedStepLength,
		G4int	navigatorId,
		G4int	stepNo,
		G4double &	pNewSafety,
		ELimited &	limitedStep,
		G4FieldTrack &	EndState,
		G4VPhysicalVolume *	currentVolume
	)

Definition at line 151 of file G4PathFinder.cc.

References DoNextCurvedStep(), DoNextLinearStep(), FatalException, G4PropagatorInField::FindAndSetFieldManager(), G4cout, G4endl, G4Exception(), G4FieldTrack::GetCharge(), G4FieldManager::GetDetectorField(), G4FieldTrack::GetMomentumDirection(), G4FieldTrack::GetPosition(), Locate(), and MovePoint().

Referenced by G4WeightWindowProcess::AlongStepGetPhysicalInteractionLength(), G4WeightCutOffProcess::AlongStepGetPhysicalInteractionLength(), G4ParallelWorldScoringProcess::AlongStepGetPhysicalInteractionLength(), G4ParallelWorldProcess::AlongStepGetPhysicalInteractionLength(), G4ImportanceProcess::AlongStepGetPhysicalInteractionLength(), G4FastSimulationManagerProcess::AlongStepGetPhysicalInteractionLength(), and G4CoupledTransportation::AlongStepGetPhysicalInteractionLength().

{
  G4double  possibleStep= -1.0; 

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  { 
    G4cout << " -------------------------" <<  G4endl;
    G4cout << " G4PathFinder::ComputeStep - entered " << G4endl;
    G4cout << "   - stepNo = "  << std::setw(4) << stepNo  << " "
           << " navigatorId = " << std::setw(2) << navigatorNo  << " "
           << " proposed step len = " << proposedStepLength << " " << G4endl;
    G4cout << " PF::ComputeStep requested step " 
           << " from " << InitialFieldTrack.GetPosition()
           << " dir  " << InitialFieldTrack.GetMomentumDirection() << G4endl;
  }
#endif
#ifdef G4VERBOSE
  if( navigatorNo >= fNoActiveNavigators )
  {
    std::ostringstream message;
    message << "Bad Navigator ID !" << G4endl
            << "        Requested Navigator ID = " << navigatorNo << G4endl
            << "        Number of active navigators = " << fNoActiveNavigators;
    G4Exception("G4PathFinder::ComputeStep()", "GeomNav0002",
                FatalException, message); 
  }
#endif

  if( fNewTrack || (stepNo != fLastStepNo)  )
  {
    // This is a new track or a new step, so we must make the step
    // ( else we can simply retrieve its results for this Navigator Id )    

    G4FieldTrack currentState= InitialFieldTrack;

    fCurrentStepNo = stepNo; 

    // Check whether a process shifted the position 
    // since the last step -- by physics processes
    //
    G4ThreeVector newPosition = InitialFieldTrack.GetPosition();   
    G4ThreeVector moveVector= newPosition - fLastLocatedPosition; 
    G4double moveLenSq= moveVector.mag2(); 
    if( moveLenSq > kCarTolerance * kCarTolerance )
    { 
       G4ThreeVector newDirection = InitialFieldTrack.GetMomentumDirection();   
#ifdef G4DEBUG_PATHFINDER
       if( fVerboseLevel > 2 )
       { 
          G4double moveLen= std::sqrt( moveLenSq ); 
          G4cout << " G4PathFinder::ComputeStep : Point moved since last step " 
                 << " -- at step # = " << stepNo << G4endl
                 << " by " << moveLen  << " to " << newPosition << G4endl;      
       } 
#endif
       MovePoint();  // Unintentional changed -- ????

       // Relocate to cope with this move -- else could abort !?
       //
       Locate( newPosition, newDirection ); 
    }

    // Check whether the particle have an (EM) field force exerting upon it
    //
    G4double particleCharge=  currentState.GetCharge(); 

    G4FieldManager* fieldMgr=0;
    G4bool          fieldExertsForce = false ;
    if( (particleCharge != 0.0) )
    {
        fieldMgr= fpFieldPropagator->FindAndSetFieldManager( currentVolume );

        // Protect for case where field manager has no field (= field is zero)
        //
        fieldExertsForce = (fieldMgr != 0) 
                        && (fieldMgr->GetDetectorField() != 0);
    }
    fFieldExertedForce = fieldExertsForce;  // Store for use in later calls
                                            // referring to this 'step'.

    fNoGeometriesLimiting= -1;  // At start of track, no process limited step
    if( fieldExertsForce )
    {
       DoNextCurvedStep( currentState, proposedStepLength, currentVolume ); 
       //--------------
    }else{
       DoNextLinearStep( currentState, proposedStepLength ); 
       //--------------
    }
    fLastStepNo= stepNo; 

#ifdef  G4DEBUG_PATHFINDER
    if ( (fNoGeometriesLimiting < 0)
      || (fNoGeometriesLimiting > fNoActiveNavigators) )
    {
      std::ostringstream message;
      message << "Number of geometries limiting the step not set." << G4endl
              << "        Number of geometries limiting step = "
              << fNoGeometriesLimiting;
      G4Exception("G4PathFinder::ComputeStep()", 
                  "GeomNav0002", FatalException, message); 
    }
#endif
  }
#ifdef G4DEBUG_PATHFINDER      
  else
  {
     if( proposedStepLength < fTrueMinStep )  // For 2nd+ geometry 
     { 
       std::ostringstream message;
       message << "Problem in step size request." << G4endl
               << "        Error can be caused by incorrect process ordering."
               << "        Being requested to make a step which is shorter"
               << " than the minimum Step " << G4endl
               << "        already computed for any Navigator/geometry during"
               << " this tracking-step: " << G4endl
               << "        This can happen due to an error in process ordering."
               << G4endl
               << "        Check that all physics processes are registered"
               << G4endl
               << "        before all processes with a navigator/geometry."
               << G4endl
               << "        If using pre-packaged physics list and/or"
               << G4endl
               << "        functionality, please report this error."
               << G4endl << G4endl
               << "        Additional information for problem: "  << G4endl
               << "        Steps request/proposed = " << proposedStepLength
               << G4endl
               << "        MinimumStep (true) = " << fTrueMinStep
               << G4endl
               << "        MinimumStep (navraw)  = " << fMinStep
               << G4endl
               << "        Navigator raw return value" << G4endl
               << "        Requested step now = " << proposedStepLength
               << G4endl
               << "        Difference min-req = "
               << fTrueMinStep-proposedStepLength << G4endl
               << "     -- Step info> stepNo= " << stepNo
               << " last= " << fLastStepNo 
               << " newTr= " << fNewTrack << G4endl;
        G4Exception("G4PathFinder::ComputeStep()", 
                    "GeomNav0003", FatalException, message);
     }
     else
     { 
        // This is neither a new track nor a new step -- just another 
        // client accessing information for the current track, step 
        // We will simply retrieve the results of the synchronous
        // stepping for this Navigator Id below.
        //
        if( fVerboseLevel > 1 )
        { 
           G4cout << " G4P::CS -> Not calling DoNextLinearStep: " 
                  << " stepNo= " << stepNo << " last= " << fLastStepNo 
                  << " new= " << fNewTrack << " Step already done" << G4endl; 
        }
     } 
  }
#endif

  fNewTrack= false; 

  // Prepare the information to return

  pNewSafety  = fCurrentPreStepSafety[ navigatorNo ]; 
  limitedStep = fLimitedStep[ navigatorNo ];
  fRelocatedPoint= false;

  possibleStep= std::min(proposedStepLength, fCurrentStepSize[ navigatorNo ]);
  EndState = fEndState;  //  now corrected for smaller step, if needed

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 0 )
  { 
    G4cout << " G4PathFinder::ComputeStep returns "
           << fCurrentStepSize[ navigatorNo ]
           << " for Navigator " << navigatorNo 
           << " Limited step = " << limitedStep 
           << " Safety(mm) = " << pNewSafety / mm 
           << G4endl; 
  }
#endif

  return possibleStep;
}

G4TouchableHandle G4PathFinder::CreateTouchableHandle

(

G4int

navId

)

const

Definition at line 765 of file G4PathFinder.cc.

References G4cout, G4endl, G4TouchableHistory::GetHistory(), G4VPhysicalVolume::GetName(), GetNavigator(), and G4TouchableHistory::UpdateYourself().

Referenced by G4WeightWindowProcess::PostStepDoIt(), G4WeightCutOffProcess::PostStepDoIt(), G4ParallelWorldScoringProcess::PostStepDoIt(), G4ParallelWorldProcess::PostStepDoIt(), G4ImportanceProcess::PostStepDoIt(), G4CoupledTransportation::PostStepDoIt(), G4WeightWindowProcess::StartTracking(), G4WeightCutOffProcess::StartTracking(), G4ParallelWorldScoringProcess::StartTracking(), G4ParallelWorldProcess::StartTracking(), and G4ImportanceProcess::StartTracking().

{
#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << "G4PathFinder::CreateTouchableHandle : navId = "
           << navId << " -- " << GetNavigator(navId) << G4endl;
  }
#endif

  G4TouchableHistory* touchHist;
  touchHist= GetNavigator(navId) -> CreateTouchableHistory(); 

  G4VPhysicalVolume* locatedVolume= fLocatedVolume[navId]; 
  if( locatedVolume == 0 )
  {
     // Workaround to ensure that the touchable is fixed !! // TODO: fix

     touchHist->UpdateYourself( locatedVolume, touchHist->GetHistory() );
  }
 
#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {   
    G4String VolumeName("None"); 
    if( locatedVolume ) { VolumeName= locatedVolume->GetName(); }
    G4cout << " Touchable History created at address " << touchHist
           << "  volume = " << locatedVolume << " name= " << VolumeName
           << G4endl;
  }
#endif

  return G4TouchableHandle(touchHist); 
}

G4double G4PathFinder::DoNextCurvedStep	(	const G4FieldTrack &	FieldTrack,
		G4double	proposedStepLength,
		G4VPhysicalVolume *	pCurrentPhysVolume
	)			[protected]

Definition at line 1137 of file G4PathFinder.cc.

References ComputeSafety(), G4PropagatorInField::ComputeStep(), FatalException, G4cout, G4endl, G4Exception(), G4FieldTrack::GetPosition(), kDoNot, LimitedString(), G4MultiNavigator::ObtainFinalStep(), and PrintLimited().

Referenced by ComputeStep().

{
  const G4double toleratedRelativeError= 1.0e-10; 
  G4double minStep= kInfinity, newSafety=0.0;
  G4int numNav; 
  G4FieldTrack  fieldTrack= initialState;
  G4ThreeVector startPoint= initialState.GetPosition(); 

#ifdef G4DEBUG_PATHFINDER
  G4int prc= G4cout.precision(9);
  if( fVerboseLevel > 2 )
  {
    G4cout << " G4PathFinder::DoNextCurvedStep ****** " << G4endl;
    G4cout << " Initial value of field track is " << fieldTrack 
           << " and proposed step= " << proposedStepLength  << G4endl;
  }
#endif

  fPreStepCenterRenewed= true; // Always update PreSafety with PreStep point

  if( fNoActiveNavigators > 1 )
  { 
     // Calculate the safety values before making the step

     G4double minSafety= kInfinity, safety; 
     for( numNav=0; numNav < fNoActiveNavigators; ++numNav )
     {
        safety= fpNavigator[numNav]->ComputeSafety( startPoint, false );
        fPreSafetyValues[numNav]= safety; 
        fCurrentPreStepSafety[numNav]= safety; 
        minSafety = std::min( safety, minSafety ); 
     }

     // Save safety value, related position

     fPreSafetyLocation=  startPoint;   
     fPreSafetyMinValue=  minSafety;
     fPreStepLocation=    startPoint;
     fMinSafety_PreStepPt= minSafety;
  }

  // Allow Propagator In Field to do the hard work, calling G4MultiNavigator
  //
  minStep=  fpFieldPropagator->ComputeStep( fieldTrack,
                                            proposedStepLength,
                                            newSafety, 
                                            pCurrentPhysicalVolume );

  // fieldTrack now contains the endpoint information
  //
  fEndState= fieldTrack; 
  fMinStep=   minStep; 
  fTrueMinStep = std::min( minStep, proposedStepLength );

  if( fNoActiveNavigators== 1 )
  { 
     // Update the 'PreSafety' sphere - as any ComputeStep was called 
     // (must be done anyway in field)

     fPreSafetyValues[0]=   newSafety;
     fPreSafetyLocation= startPoint;   
     fPreSafetyMinValue= newSafety;

     // Update the current 'PreStep' point's values - mandatory
     //
     fCurrentPreStepSafety[0]= newSafety; 
     fPreStepLocation=  startPoint;
     fMinSafety_PreStepPt= newSafety;
  }

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << "G4PathFinder::DoNextCurvedStep : " << G4endl
           << " initialState = " << initialState << G4endl
           << " and endState = " << fEndState << G4endl;
    G4cout << "G4PathFinder::DoNextCurvedStep : " 
           << " minStep = " << minStep 
           << " proposedStepLength " << proposedStepLength 
           << " safety = " << newSafety << G4endl;
  }
#endif
  G4double currentStepSize;   // = 0.0; 
  if( minStep < proposedStepLength ) // if == , then a boundary found at end ??
  {   
    // Recover the remaining information from MultiNavigator
    // especially regarding which Navigator limited the step

    G4int noLimited= 0;  //   No geometries limiting step
    for( numNav=0; numNav < fNoActiveNavigators; ++numNav )
    {
      G4double finalStep, lastPreSafety=0.0, minStepLast;
      ELimited didLimit; 
      G4bool limited; 

      finalStep=  fpMultiNavigator->ObtainFinalStep( numNav, lastPreSafety, 
                                                     minStepLast, didLimit );

      // Calculate the step for this geometry, using the 
      // final step (the only one which can differ.)

      currentStepSize = fTrueMinStep;  
      G4double diffStep= 0.0; 
      if( (minStepLast != kInfinity) )
      { 
        diffStep = (finalStep-minStepLast);
        if ( std::abs(diffStep) <= toleratedRelativeError * finalStep ) 
        {
          diffStep = 0.0;
        }
        currentStepSize += diffStep; 
      }
      fCurrentStepSize[numNav] = currentStepSize;  
      
      // TODO: could refine the way to obtain safeties for > 1 geometries
      //     - for pre step safety
      //        notify MultiNavigator about new set of sub-steps
      //        allow it to return this value in ObtainFinalStep 
      //        instead of lastPreSafety (or as well?)
      //     - for final step start (available)
      //        get final Step start from MultiNavigator
      //        and corresponding safety values
      // and/or ALSO calculate ComputeSafety at endpoint
      //     endSafety= fpNavigator[numNav]->ComputeSafety( endPoint ); 

      fLimitedStep[numNav] = didLimit; 
      fLimitTruth[numNav] = limited = (didLimit != kDoNot ); 
      if( limited ) { noLimited++; }

#ifdef G4DEBUG_PATHFINDER
      G4bool StepError= (currentStepSize < 0) 
                   || ( (minStepLast != kInfinity) && (diffStep < 0) ) ; 
      if( StepError || (fVerboseLevel > 2) )
      {
        G4String  limitedString=  LimitedString( fLimitedStep[numNav] ); 
        
        G4cout << " G4PathFinder::ComputeStep. Geometry " << numNav
               << "  step= " << fCurrentStepSize[numNav] 
               << " from final-step= " << finalStep 
               << " fTrueMinStep= " << fTrueMinStep 
               << " minStepLast= "  << minStepLast 
               << "  limited = " << (fLimitTruth[numNav] ? "YES" : " NO")
               << " ";
        G4cout << "  status = " << limitedString << " #= " << didLimit
               << G4endl;
        
        if( StepError )
        { 
          std::ostringstream message;
          message << "Incorrect calculation of step size for one navigator"
                  << G4endl
                  << "        currentStepSize = " << currentStepSize 
                  << ", diffStep= " << diffStep << G4endl
                  << "ERROR in computing step size for this navigator.";
          G4Exception("G4PathFinder::DoNextCurvedStep",
                      "GeomNav0003", FatalException, message);
        }
      }
#endif
    } // for num Navigators

    fNoGeometriesLimiting= noLimited;  // Save # processes limiting step
  } 
  else if ( (minStep == proposedStepLength)  
            || (minStep == kInfinity)  
            || ( std::abs(minStep-proposedStepLength)
               < toleratedRelativeError * proposedStepLength ) )
  { 
    // In case the step was not limited, use default responses
    //  --> all Navigators 
    // Also avoid problems in case of PathFinder using safety to optimise
    //  - it is possible that the Navigators were not called
    //    if the safety was already satisfactory.
    //    (In that case calling ObtainFinalStep gives invalid results.)

    currentStepSize= minStep;
    for( numNav=0; numNav < fNoActiveNavigators; ++numNav )
    {
      fCurrentStepSize[numNav] = minStep; 
      // Safety for endpoint ??  // Can eventuall improve it -- see TODO above
      fLimitedStep[numNav] = kDoNot; 
      fLimitTruth[numNav] = false; 
    }
    fNoGeometriesLimiting= 0;  // Save # processes limiting step
  } 
  else    //  (minStep > proposedStepLength) and not (minStep == kInfinity)
  {
    std::ostringstream message;
    message << "Incorrect calculation of step size for one navigator." << G4endl
            << "        currentStepSize = " << minStep << " is larger than "
            << " proposed StepSize = " << proposedStepLength << ".";
    G4Exception("G4PathFinder::DoNextCurvedStep()",
                "GeomNav0003", FatalException, message); 
  }

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << " Exiting G4PathFinder::DoNextCurvedStep " << G4endl;
    PrintLimited(); 
  }
  G4cout.precision(prc); 
#endif

  return minStep; 
}

G4double G4PathFinder::DoNextLinearStep	(	const G4FieldTrack &	FieldTrack,
		G4double	proposedStepLength
	)			[protected]

Definition at line 801 of file G4PathFinder.cc.

References G4cout, G4endl, G4FieldTrack::GetMomentumDirection(), G4FieldTrack::GetPosition(), kDoNot, kUnique, G4FieldTrack::SetPosition(), G4FieldTrack::SetProperTimeOfFlight(), sqr(), and WhichLimited().

Referenced by ComputeStep().

{
  std::vector<G4Navigator*>::iterator pNavigatorIter;
  G4double safety= 0.0, step=0.0;
  G4double minSafety= kInfinity, minStep;

  const G4int IdTransport= 0;  // Id of Mass Navigator !!
  register G4int num=0; 

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << " G4PathFinder::DoNextLinearStep : entered " << G4endl;
    G4cout << "   Input field track= " << initialState << G4endl;
    G4cout << "   Requested step= " << proposedStepLength << G4endl;
  }
#endif

  G4ThreeVector initialPosition= initialState.GetPosition(); 
  G4ThreeVector initialDirection= initialState.GetMomentumDirection();
  
  G4ThreeVector OriginShift = initialPosition - fPreSafetyLocation;
  G4double      MagSqShift  = OriginShift.mag2() ;
  G4double      MagShift;  // Only given value if it larger than minimum safety

  // Potential optimisation using Maximum Value of safety!
  // if( MagSqShift >= sqr(fPreSafetyMaxValue ) ){ 
  //   MagShift= kInfinity;   // Not a useful value -- all will not use/ignore
  // else
  //  MagShift= std::sqrt(MagSqShift) ;

  MagShift= std::sqrt(MagSqShift) ;

#ifdef G4PATHFINDER_OPTIMISATION

  G4double fullSafety;  // For all geometries, for prestep point

  if( MagSqShift >= sqr(fPreSafetyMinValue ) )
  {
     fullSafety = 0.0 ;     
  }
  else
  {
     fullSafety = fPreSafetyMinValue - MagShift;
  }
  if( proposedStepLength < fullSafety ) 
  {
     // Move is smaller than all safeties
     //  -> so we do not have to move the safety center

     fPreStepCenterRenewed= false;

     for( num=0; num< fNoActiveNavigators; ++num )
     {
        fCurrentStepSize[num]= kInfinity; 
        safety = std::max( 0.0,  fPreSafetyValues[num] - MagShift); 
        minSafety= std::min( safety, minSafety ); 
        fCurrentPreStepSafety[num]= safety; 
     }
     minStep= kInfinity;

#ifdef G4DEBUG_PATHFINDER
     if( fVerboseLevel > 2 )
     {
       G4cout << "G4PathFinder::DoNextLinearStep : Quick Stepping. " << G4endl
               << " proposedStepLength " <<  proposedStepLength
               << " < (full) safety = " << fullSafety 
               << " at " << initialPosition 
               << G4endl;
     }
#endif
  }
  else
#endif   // End of G4PATHFINDER_OPTIMISATION 1
  {
     // Move is larger than at least one of the safeties
     //  -> so we must move the safety center!

     fPreStepCenterRenewed= true;
     pNavigatorIter= fpTransportManager-> GetActiveNavigatorsIterator();

     minStep= kInfinity;  // Not proposedStepLength; 

     for( num=0; num< fNoActiveNavigators; ++pNavigatorIter,++num ) 
     {
        safety = std::max( 0.0,  fPreSafetyValues[num] - MagShift); 

#ifdef G4PATHFINDER_OPTIMISATION
        if( proposedStepLength <= safety )  // Should be just < safety ?
        {
           // The Step is guaranteed to be taken

           step= kInfinity;    //  ComputeStep Would return this

#ifdef G4DEBUG_PATHFINDER
           G4cout.precision(8); 
           G4cout << "PathFinder::ComputeStep> small proposed step = "
                  << proposedStepLength
                  << " <=  safety = " << safety << " for nav " << num 
                  << " Step fully taken. " << G4endl;
#endif
        }
        else
#endif   // End of G4PATHFINDER_OPTIMISATION 2
        {
#ifdef G4DEBUG_PATHFINDER
           G4double previousSafety= safety; 
#endif
           step= (*pNavigatorIter)->ComputeStep( initialPosition, 
                                                 initialDirection,
                                                 proposedStepLength,
                                                 safety ); 
           minStep  = std::min( step,  minStep);

           //  TODO: consider whether/how to reduce the proposed step 
           //        to the latest minStep value - to reduce calculations

#ifdef G4DEBUG_PATHFINDER
           if( fVerboseLevel > 0)
           {
             G4cout.precision(8); 
             G4cout << "PathFinder::ComputeStep> long  proposed step = "
                    << proposedStepLength
                    << "  >  safety = " << previousSafety
                    << " for nav " << num 
                    << " .  New safety = " << safety << " step= " << step
                    << G4endl;      
           } 
#endif
        }
        fCurrentStepSize[num] = step; 

        // Save safety value, must be done for all geometries "together"
        // (even if not recomputed using call to ComputeStep)
        // since they share the fPreSafetyLocation

        fPreSafetyValues[num]= safety; 
        fCurrentPreStepSafety[num]= safety; 

        minSafety= std::min( safety, minSafety ); 
           
#ifdef G4DEBUG_PATHFINDER
        if( fVerboseLevel > 2 )
        {
          G4cout << "G4PathFinder::DoNextLinearStep : Navigator ["
                 << num << "] -- step size " << step << G4endl;
        }
#endif
     }

     // Only change these when safety is recalculated
     // it is good/relevant only for safety calculations

     fPreSafetyLocation=  initialPosition; 
     fPreSafetyMinValue=  minSafety;
  } // end of else for  if( proposedStepLength <= fullSafety)

  // For use in Relocation, need PreStep point location, min-safety
  //
  fPreStepLocation= initialPosition; 
  fMinSafety_PreStepPt= minSafety; 

  fMinStep=   minStep; 

  if( fMinStep == kInfinity )
  {
     minStep = proposedStepLength;   //  Use this below for endpoint !!
  }
  fTrueMinStep = minStep;

  // Set the EndState

  G4ThreeVector endPosition;

  fEndState= initialState; 
  endPosition= initialPosition + minStep * initialDirection ; 

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 1 )
  {
    G4cout << "G4PathFinder::DoNextLinearStep : "
           << " initialPosition = " << initialPosition 
           << " and endPosition = " << endPosition<< G4endl;
  }
#endif

  fEndState.SetPosition( endPosition ); 
  fEndState.SetProperTimeOfFlight( -1.000 );   // Not defined YET

  if( fNoActiveNavigators == 1 )
  { 
     G4bool transportLimited = (fMinStep!= kInfinity); 
     fLimitTruth[IdTransport] = transportLimited; 
     fLimitedStep[IdTransport] = transportLimited ? kUnique : kDoNot;

     // Set fNoGeometriesLimiting - as WhichLimited does
     fNoGeometriesLimiting = transportLimited ? 1 : 0;  
  }
  else
  {
     WhichLimited(); 
  }

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << " G4PathFinder::DoNextLinearStep : exits returning "
           << minStep << G4endl;
    G4cout << "   Endpoint values = " << fEndState << G4endl;
    G4cout << G4endl;
  }
#endif

  return minStep;
}

void G4PathFinder::EnableParallelNavigation

(

G4bool

enableChoice = true

)

Definition at line 124 of file G4PathFinder.cc.

References G4SafetyHelper::EnableParallelNavigation(), G4TransportationManager::GetNavigatorForTracking(), G4TransportationManager::GetSafetyHelper(), and G4PropagatorInField::SetNavigatorForPropagating().

Referenced by PrepareNewTrack().

{
   G4Navigator *navigatorForPropagation=0, *massNavigator=0;

   massNavigator= fpTransportManager->GetNavigatorForTracking(); 
   if( enableChoice )
   {
      navigatorForPropagation= fpMultiNavigator;

      // Enable SafetyHelper to use PF
      //
      fpTransportManager->GetSafetyHelper()->EnableParallelNavigation(true);
   }
   else
   {
      navigatorForPropagation= massNavigator;
       
      // Disable SafetyHelper to use PF
      //
      fpTransportManager->GetSafetyHelper()->EnableParallelNavigation(false);
   }
   fpFieldPropagator->SetNavigatorForPropagating(navigatorForPropagation);
}

G4double G4PathFinder::GetCurrentSafety

(

)

const [inline]

Definition at line 298 of file G4PathFinder.hh.

Referenced by G4CoupledTransportation::AlongStepGetPhysicalInteractionLength().

{
  return fMinSafety_PreStepPt;
}

G4PathFinder * G4PathFinder::GetInstance

(

)

[static]

Definition at line 57 of file G4PathFinder.cc.

Referenced by G4CoupledTransportation::G4CoupledTransportation(), G4FastSimulationManagerProcess::G4FastSimulationManagerProcess(), G4ImportanceProcess::G4ImportanceProcess(), G4ParallelWorldProcess::G4ParallelWorldProcess(), G4ParallelWorldScoringProcess::G4ParallelWorldScoringProcess(), G4WeightCutOffProcess::G4WeightCutOffProcess(), G4WeightWindowProcess::G4WeightWindowProcess(), and G4SafetyHelper::InitialiseNavigator().

{
   static G4PathFinder theInstance; 
   if( ! fpPathFinder )
   {
     fpPathFinder = &theInstance; 
   }
   return fpPathFinder;
}

G4VPhysicalVolume * G4PathFinder::GetLocatedVolume

(

G4int

navId

)

const [inline]

Definition at line 275 of file G4PathFinder.hh.

Referenced by G4FastSimulationManagerProcess::AtRestGetPhysicalInteractionLength(), and G4FastSimulationManagerProcess::PostStepGetPhysicalInteractionLength().

{
  G4VPhysicalVolume* vol=0;  
  if( (navId < fMaxNav) && (navId >=0) ) { vol= fLocatedVolume[navId]; }
  return vol; 
}

G4int G4PathFinder::GetMaxLoopCount

(

)

const [inline]

G4double G4PathFinder::GetMinimumStep

(

)

const [inline]

Definition at line 287 of file G4PathFinder.hh.

{ 
  return fMinStep; 
} 

G4Navigator * G4PathFinder::GetNavigator

(

G4int

n

)

const [inline, protected]

Definition at line 308 of file G4PathFinder.hh.

Referenced by CreateTouchableHandle(), and PrintLimited().

{ 
  if( (n>fNoActiveNavigators)||(n<0)) { n=0; }
  return fpNavigator[n];
}

unsigned int G4PathFinder::GetNumberGeometriesLimitingStep

(

)

const [inline]

Definition at line 292 of file G4PathFinder.hh.

Referenced by G4CoupledTransportation::AlongStepGetPhysicalInteractionLength().

{
  unsigned int noGeometries=fNoGeometriesLimiting;
  return noGeometries; 
}

G4bool G4PathFinder::IsParticleLooping

(

)

const [inline]

G4double G4PathFinder::LastPreSafety	(	G4int	navId,
		G4ThreeVector &	globalCenterPoint,
		G4double &	minSafety
	)			[inline]

Definition at line 321 of file G4PathFinder.hh.

{
  globalCenterPoint= fPreSafetyLocation;
  minSafety=         fPreSafetyMinValue;
  //  navId = std::min( navId, fMaxNav-1 ); 
  return  fPreSafetyValues[ navId ];
}

G4String & G4PathFinder::LimitedString

(

ELimited

lim

)

Definition at line 1346 of file G4PathFinder.cc.

References kDoNot, kSharedOther, kSharedTransport, and kUnique.

Referenced by DoNextCurvedStep(), and PrintLimited().

{
  static G4String StrDoNot("DoNot"),
                  StrUnique("Unique"),
                  StrUndefined("Undefined"),
                  StrSharedTransport("SharedTransport"),  
                  StrSharedOther("SharedOther");

  G4String* limitedStr;
  switch ( lim )
  {
     case kDoNot:  limitedStr= &StrDoNot; break;
     case kUnique: limitedStr = &StrUnique; break; 
     case kSharedTransport:  limitedStr= &StrSharedTransport; break; 
     case kSharedOther: limitedStr = &StrSharedOther; break;
     default: limitedStr = &StrUndefined; break;
  }
  return *limitedStr;
}

void G4PathFinder::Locate	(	const G4ThreeVector &	position,
		const G4ThreeVector &	direction,
		G4bool	relativeSearch = true
	)

Definition at line 458 of file G4PathFinder.cc.

References G4cout, G4endl, G4TransportationManager::GetActiveNavigatorsIterator(), G4FieldTrack::GetPosition(), kDoNot, and ReportMove().

Referenced by ComputeStep(), G4SafetyHelper::Locate(), G4CoupledTransportation::PostStepDoIt(), and PrepareNewTrack().

{
  // Locate the point in each geometry

  std::vector<G4Navigator*>::iterator pNavIter=
     fpTransportManager->GetActiveNavigatorsIterator(); 

  G4ThreeVector lastEndPosition= fEndState.GetPosition(); 
  G4ThreeVector moveVec = (position - lastEndPosition );
  G4double      moveLenSq= moveVec.mag2();
  if( (!fNewTrack) && (!fRelocatedPoint)
   && ( moveLenSq> kCarTolerance*kCarTolerance ) )
  {
     ReportMove( position, lastEndPosition, "Position" ); 
  }
  fLastLocatedPosition= position; 

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << G4endl; 
    G4cout << " G4PathFinder::Locate : entered " << G4endl;
    G4cout << " --------------------   -------" <<  G4endl;
    G4cout << "   Locating at position " << position
           << "  with direction " << direction 
           << "  relative= " << relative << G4endl;
    if ( (fVerboseLevel > 1) || ( moveLenSq > 0.0) )
    { 
       G4cout << "  lastEndPosition = " << lastEndPosition
              << "  moveVec = " << moveVec
              << "  newTr = " << fNewTrack 
              << "  relocated = " << fRelocatedPoint << G4endl;
    }

    G4cout << " Located at " << position ; 
    if( fNoActiveNavigators > 1 )  { G4cout << G4endl; }
  }
#endif

  for ( register G4int num=0; num< fNoActiveNavigators ; ++pNavIter,++num )
  {
     //  ... who limited the step ....

     if( fLimitTruth[num] ) { (*pNavIter)->SetGeometricallyLimitedStep(); }

     G4VPhysicalVolume *pLocated= 
     (*pNavIter)->LocateGlobalPointAndSetup( position, &direction,
                                             relative,  
                                             false);   
     // Set the state related to the location
     //
     fLocatedVolume[num] = pLocated; 

     // Clear state related to the step
     //
     fLimitedStep[num]   = kDoNot; 
     fCurrentStepSize[num] = 0.0;      
    
#ifdef G4DEBUG_PATHFINDER
     if( fVerboseLevel > 2 )
     {
       G4cout << " - In world " << num << " geomLimStep= " << fLimitTruth[num]
              << "  gives volume= " << pLocated ; 
       if( pLocated )
       { 
         G4cout << "  name = '" << pLocated->GetName() << "'"; 
         G4cout << " - CopyNo= " << pLocated->GetCopyNo(); 
       } 
       G4cout  << G4endl; 
     }
#endif
  }

  fRelocatedPoint= false;
}

void G4PathFinder::MovePoint

(

)

[inline]

Definition at line 303 of file G4PathFinder.hh.

Referenced by ComputeStep(), and PrepareNewTrack().

{
  fRelocatedPoint= true;
}

G4double G4PathFinder::ObtainSafety	(	G4int	navId,
		G4ThreeVector &	globalCenterPoint
	)			[inline]

Definition at line 314 of file G4PathFinder.hh.

Referenced by G4CoupledTransportation::AlongStepGetPhysicalInteractionLength().

{
  globalCenterPoint= fSafetyLocation; 
  //  navId = std::min( navId, fMaxNav-1 ); 
  return  fNewSafetyComputed[ navId ];
}

void G4PathFinder::PrepareNewTrack	(	const G4ThreeVector &	position,
		const G4ThreeVector &	direction,
		G4VPhysicalVolume *	massStartVol = 0
	)

Definition at line 349 of file G4PathFinder.cc.

References EnableParallelNavigation(), FatalException, G4endl, G4Exception(), G4TransportationManager::GetActiveNavigatorsIterator(), G4TransportationManager::GetSafetyHelper(), G4SafetyHelper::InitialiseHelper(), kDoNot, Locate(), MovePoint(), and G4MultiNavigator::PrepareNavigators().

Referenced by G4WeightWindowProcess::StartTracking(), G4WeightCutOffProcess::StartTracking(), G4ParallelWorldScoringProcess::StartTracking(), G4ParallelWorldProcess::StartTracking(), G4ImportanceProcess::StartTracking(), G4FastSimulationManagerProcess::StartTracking(), and G4CoupledTransportation::StartTracking().

{
  // Key purposes:
  //   - Check and cache set of active navigators
  //   - Reset state for new track

  G4int num=0; 

  EnableParallelNavigation(true); 
    // Switch PropagatorInField to use MultiNavigator

  fpTransportManager->GetSafetyHelper()->InitialiseHelper(); 
    // Reinitialise state of safety helper -- avoid problems with overlaps

  fNewTrack= true; 
  this->MovePoint();   // Signal further that the last status is wiped

  // Message the G4NavigatorPanel / Dispatcher to find active navigators
  //
  std::vector<G4Navigator*>::iterator pNavigatorIter; 

  fNoActiveNavigators=  fpTransportManager-> GetNoActiveNavigators();
  if( fNoActiveNavigators > fMaxNav )
  {
    std::ostringstream message;
    message << "Too many active Navigators / worlds." << G4endl
            << "        Transportation Manager has "
            << fNoActiveNavigators << " active navigators." << G4endl
            << "        This is more than the number allowed = "
            << fMaxNav << " !";
    G4Exception("G4PathFinder::PrepareNewTrack()", "GeomNav0002",  
                FatalException, message); 
  }

  fpMultiNavigator->PrepareNavigators(); 
  //------------------------------------

  pNavigatorIter= fpTransportManager->GetActiveNavigatorsIterator();
  for( num=0; num< fNoActiveNavigators; ++pNavigatorIter,++num )
  {
     // Keep information in C-array ... for creating touchables - at least

     fpNavigator[num] =  *pNavigatorIter;   
     fLimitTruth[num] = false;
     fLimitedStep[num] = kDoNot;
     fCurrentStepSize[num] = 0.0; 
     fLocatedVolume[num] = 0; 
  }
  fNoGeometriesLimiting= 0;  // At start of track, no process limited step

  // In case of one geometry, the tracking will have done the locating!!

  if( fNoActiveNavigators > 1 )
  {
     Locate( position, direction, false );   
  }
  else
  {
     // Update state -- depending on the tracking's call to Mass Navigator

     fLastLocatedPosition= position; 
     fLocatedVolume[0]= massStartVol; // This information must be given
                                      // by transportation
     fLimitedStep[0]   = kDoNot; 
     fCurrentStepSize[0] = 0.0;
  }

  // Reset Safety Information -- as in case of overlaps this can cause
  // inconsistencies ...
  //
  fMinSafety_PreStepPt= fPreSafetyMinValue= fMinSafety_atSafLocation= 0.0; 
 
  for( num=0; num< fNoActiveNavigators; ++num )
  {
     fPreSafetyValues[num]= 0.0; 
     fNewSafetyComputed[num]= 0.0; 
     fCurrentPreStepSafety[num] = 0.0;
  }

  // The first location for each Navigator must be non-relative
  // or else call ResetStackAndState() for each Navigator

  fRelocatedPoint= false; 
}

void G4PathFinder::PrintLimited

(

)

[protected]

Definition at line 1076 of file G4PathFinder.cc.

References G4cout, G4endl, G4VPhysicalVolume::GetName(), GetNavigator(), G4Navigator::GetWorldVolume(), and LimitedString().

Referenced by DoNextCurvedStep(), and WhichLimited().

{
  // Report results -- for checking   

  G4cout << "G4PathFinder::PrintLimited reports: " ; 
  G4cout << "  Minimum step (true)= " << fTrueMinStep 
         << "  reported min = " << fMinStep 
         << G4endl; 
  if(  (fCurrentStepNo <= 2) || (fVerboseLevel>=2) )
  {
    G4cout << std::setw(5) << " Step#"  << " "
           << std::setw(5) << " NavId"  << " "
           << std::setw(12) << " step-size " << " "
           << std::setw(12) << " raw-size "  << " "
           << std::setw(12) << " pre-safety " << " " 
           << std::setw(15) << " Limited / flag"  << " "
           << std::setw(15) << "  World "  << " "
           << G4endl;  
  }
  G4int num;
  for ( num= 0; num < fNoActiveNavigators; num++ )
  { 
    G4double rawStep = fCurrentStepSize[num]; 
    G4double stepLen = fCurrentStepSize[num]; 
    if( stepLen > fTrueMinStep )
    { 
      stepLen = fTrueMinStep;     // did not limit (went as far as asked)
    }
    G4int oldPrec= G4cout.precision(9); 

    G4cout << std::setw(5) << fCurrentStepNo  << " " 
           << std::setw(5) << num  << " "
           << std::setw(12) << stepLen << " "
           << std::setw(12) << rawStep << " "
           << std::setw(12) << fCurrentPreStepSafety[num] << " "
           << std::setw(5) << (fLimitTruth[num] ? "YES" : " NO") << " ";
    G4String limitedStr= LimitedString(fLimitedStep[num]); 
    G4cout << " " << std::setw(15) << limitedStr << " ";  
    G4cout.precision(oldPrec); 

    G4Navigator *pNav= GetNavigator( num ); 
    G4String  WorldName( "Not-Set" ); 
    if (pNav)
    {
       G4VPhysicalVolume *pWorld= pNav->GetWorldVolume(); 
       if( pWorld )
       {
           WorldName = pWorld->GetName(); 
       }
    }
    G4cout << " " << WorldName ; 
    G4cout << G4endl;
  }

  if( fVerboseLevel > 4 )
  {
    G4cout << " G4PathFinder::PrintLimited - exiting. " << G4endl;
  }
}

void G4PathFinder::PushPostSafetyToPreSafety

(

)

Definition at line 1366 of file G4PathFinder.cc.

{
  fPreSafetyLocation= fSafetyLocation;
  fPreSafetyMinValue= fMinSafety_atSafLocation;
  for( register G4int nav=0; nav < fNoActiveNavigators; ++nav )
  {
     fPreSafetyValues[nav]= fNewSafetyComputed[nav];
  }
}

void G4PathFinder::ReLocate

(

const G4ThreeVector &

position

)

Definition at line 536 of file G4PathFinder.cc.

References ComputeSafety(), FatalException, G4cout, G4endl, G4Exception(), G4TransportationManager::GetActiveNavigatorsIterator(), G4GeometryTolerance::GetInstance(), G4FieldTrack::GetPosition(), G4GeometryTolerance::GetRadialTolerance(), kDoNot, and ReportMove().

Referenced by G4CoupledTransportation::PostStepDoIt(), and G4SafetyHelper::ReLocateWithinVolume().

{
  // Locate the point in each geometry

  std::vector<G4Navigator*>::iterator pNavIter=
    fpTransportManager->GetActiveNavigatorsIterator(); 

#ifdef G4DEBUG_PATHFINDER

  // Check that this relocation does not violate safety
  //   - at endpoint (computed from start point) AND
  //   - at last safety location  (likely just called)

  G4ThreeVector lastEndPosition= fEndState.GetPosition();

  // Calculate end-point safety ...
  //
  G4double      DistanceStartEnd= (lastEndPosition - fPreStepLocation).mag();
  G4double      endPointSafety_raw = fMinSafety_PreStepPt - DistanceStartEnd; 
  G4double      endPointSafety_Est1 = std::max( 0.0, endPointSafety_raw ); 

  // ... and check move from endpoint against this endpoint safety
  //
  G4ThreeVector moveVecEndPos  = position - lastEndPosition;
  G4double      moveLenEndPosSq = moveVecEndPos.mag2(); 

  // Check that move from endpoint of last step is within safety
  // -- or check against last location or relocation ?? 
  //
  G4ThreeVector moveVecSafety=  position - fSafetyLocation; 
  G4double      moveLenSafSq=   moveVecSafety.mag2();

  G4double distCheckEnd_sq= ( moveLenEndPosSq - endPointSafety_Est1 
                                               *endPointSafety_Est1 ); 
  G4double distCheckSaf_sq=   ( moveLenSafSq -  fMinSafety_atSafLocation
                                               *fMinSafety_atSafLocation ); 

  G4bool longMoveEnd = distCheckEnd_sq > 0.0; 
  G4bool longMoveSaf = distCheckSaf_sq > 0.0; 

  G4double revisedSafety= 0.0;

  if( (!fNewTrack) && ( longMoveEnd && longMoveSaf ) )
  {  
     // Recompute ComputeSafety for end position
     //
     revisedSafety= ComputeSafety(lastEndPosition); 

     const G4double kRadTolerance =
       G4GeometryTolerance::GetInstance()->GetRadialTolerance();
     const G4double cErrorTolerance=1e-12;   
       // Maximum relative error from roundoff of arithmetic 

     G4double  distCheckRevisedEnd= moveLenEndPosSq-revisedSafety*revisedSafety;

     G4bool  longMoveRevisedEnd=  ( distCheckRevisedEnd > 0. ) ; 

     G4double  moveMinusSafety= 0.0; 
     G4double  moveLenEndPosition= std::sqrt( moveLenEndPosSq );
     moveMinusSafety = moveLenEndPosition - revisedSafety; 

     if ( longMoveRevisedEnd && (moveMinusSafety > 0.0 )
       && ( revisedSafety > 0.0 ) )
     {
        // Take into account possibility of roundoff error causing
        // this apparent move further than safety

        if( fVerboseLevel > 0 )
        {
           G4cout << " G4PF:Relocate> Ratio to revised safety is " 
                  << std::fabs(moveMinusSafety)/revisedSafety << G4endl;
        }

        G4double  absMoveMinusSafety= std::fabs(moveMinusSafety);
        G4bool smallRatio= absMoveMinusSafety < kRadTolerance * revisedSafety ; 
        G4double maxCoordPos = std::max( 
                                      std::max( std::fabs(position.x()), 
                                                std::fabs(position.y())), 
                                      std::fabs(position.z()) );
        G4bool smallValue= absMoveMinusSafety < cErrorTolerance * maxCoordPos;
        if( ! (smallRatio || smallValue) )
        {
           G4cout << " G4PF:Relocate> Ratio to revised safety is " 
                  << std::fabs(moveMinusSafety)/revisedSafety << G4endl;
           G4cout << " Difference of move and safety is not very small."
                  << G4endl;
        }
        else
        {
          moveMinusSafety = 0.0; 
          longMoveRevisedEnd = false;   // Numerical issue -- not too long!

          G4cout << " Difference of move & safety is very small in magnitude, "
                 << absMoveMinusSafety << G4endl;
          if( smallRatio )
          {
            G4cout << " ratio to safety " << revisedSafety 
                   << " is " <<  absMoveMinusSafety / revisedSafety
                   << "smaller than " << kRadTolerance << " of safety ";
          }
          else
          {
            G4cout << " as fraction " << absMoveMinusSafety / maxCoordPos 
                   << " of position vector max-coord " << maxCoordPos
                   << " smaller than " << cErrorTolerance ;
          }
          G4cout << " -- reset moveMinusSafety to "
                 << moveMinusSafety << G4endl;
        }
     }

     if ( longMoveEnd && longMoveSaf
       && longMoveRevisedEnd && (moveMinusSafety>0.0) )
     { 
        G4int oldPrec= G4cout.precision(9); 
        std::ostringstream message;
        message << "ReLocation is further than end-safety value." << G4endl
                << " Moved from last endpoint by " << moveLenEndPosition 
                << " compared to end safety (from preStep point) = " 
                << endPointSafety_Est1 << G4endl
                << "  --> last PreSafety Location was " << fPreSafetyLocation
                << G4endl
                << "       safety value =  " << fPreSafetyMinValue << G4endl
                << "  --> last PreStep Location was " << fPreStepLocation
                << G4endl
                << "       safety value =  " << fMinSafety_PreStepPt << G4endl
                << "  --> last EndStep Location was " << lastEndPosition
                << G4endl
                << "       safety value =  " << endPointSafety_Est1 
                << " raw-value = " << endPointSafety_raw << G4endl
                << "  --> Calling again at this endpoint, we get "
                <<  revisedSafety << " as safety value."  << G4endl
                << "  --> last position for safety " << fSafetyLocation
                << G4endl
                << "       its safety value =  " << fMinSafety_atSafLocation
                << G4endl
                << "       move from safety location = "
                << std::sqrt(moveLenSafSq) << G4endl
                << "         again= " << moveVecSafety.mag() << G4endl
                << "       safety - Move-from-end= " 
                << revisedSafety - moveLenEndPosition
                << " (negative is Bad.)" << G4endl
                << " Debug:  distCheckRevisedEnd = "
                << distCheckRevisedEnd;
        ReportMove( lastEndPosition, position, "Position" ); 
        G4Exception("G4PathFinder::ReLocate", "GeomNav0003", 
                    FatalException, message); 
        G4cout.precision(oldPrec); 
    }
  }

  if( fVerboseLevel > 2 )
  {
    G4cout << G4endl; 
    G4cout << " G4PathFinder::ReLocate : entered " << G4endl;
    G4cout << " ----------------------   -------" <<  G4endl;
    G4cout << "  *Re*Locating at position " << position  << G4endl; 
      // << "  with direction " << direction 
      // << "  relative= " << relative << G4endl;
    if ( (fVerboseLevel > -1) || ( moveLenEndPosSq > 0.0) )
    {
       G4cout << "  lastEndPosition = " << lastEndPosition
              << "  moveVec from step-end = " << moveVecEndPos
              << "  is new Track = " << fNewTrack 
              << "  relocated = " << fRelocatedPoint << G4endl;
    }
  }
#endif // G4DEBUG_PATHFINDER

  for ( register G4int num=0; num< fNoActiveNavigators ; ++pNavIter,++num )
  {
     //  ... none limited the step

     (*pNavIter)->LocateGlobalPointWithinVolume( position ); 

     // Clear state related to the step
     //
     fLimitedStep[num]   = kDoNot; 
     fCurrentStepSize[num] = 0.0;      
     fLimitTruth[num] = false;   
  }

  fLastLocatedPosition= position; 
  fRelocatedPoint= false;

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 2 )
  {
    G4cout << " G4PathFinder::ReLocate : exiting " 
           << "  at position " << fLastLocatedPosition << G4endl << G4endl;
  }
#endif
}

void G4PathFinder::ReportMove	(	const G4ThreeVector &	OldV,
		const G4ThreeVector &	NewV,
		const G4String &	Quantity
	)			const [protected]

Definition at line 436 of file G4PathFinder.cc.

References G4cerr, G4endl, G4Exception(), and JustWarning.

Referenced by Locate(), and ReLocate().

{
    G4ThreeVector moveVec = ( NewVector - OldVector );

    G4int prc= G4cerr.precision(12); 
    std::ostringstream message;
    message << "Endpoint moved between value returned by ComputeStep()"
            << " and call to Locate(). " << G4endl
            << "          Change of " << Quantity << " is "
            << moveVec.mag() / mm << " mm long" << G4endl
            << "          and its vector is "
            << (1.0/mm) * moveVec << " mm " << G4endl
            << "          Endpoint of ComputeStep() was " << OldVector << G4endl
            << "          and current position to locate is " << NewVector;
    G4Exception("G4PathFinder::ReportMove()", "GeomNav1002",  
                JustWarning, message); 
    G4cerr.precision(prc); 
}

void G4PathFinder::SetChargeMomentumMass	(	G4double	charge,
		G4double	momentum,
		G4double	pMass
	)			[inline]

void G4PathFinder::SetMaxLoopCount

(

G4int

new_max

)

[inline]

G4int G4PathFinder::SetVerboseLevel

(

G4int

lev = -1

)

[inline]

Definition at line 282 of file G4PathFinder.hh.

{
  G4int old= fVerboseLevel;  fVerboseLevel= newLevel; return old;
}

G4bool G4PathFinder::UseSafetyForOptimization

(

G4bool

)

[inline, protected]

void G4PathFinder::WhichLimited

(

)

[protected]

Definition at line 1018 of file G4PathFinder.cc.

References G4cout, G4endl, kDoNot, kSharedOther, kSharedTransport, kUnique, and PrintLimited().

Referenced by DoNextLinearStep().

{
  // Flag which processes limited the step

  G4int num=-1, last=-1; 
  G4int noLimited=0; 
  ELimited shared= kSharedOther; 

  const G4int IdTransport= 0;  // Id of Mass Navigator !!

  // Assume that [IdTransport] is Mass / Transport
  //
  G4bool transportLimited = (fCurrentStepSize[IdTransport] == fMinStep)
                           && ( fMinStep!= kInfinity) ; 

  if( transportLimited )  { 
     shared= kSharedTransport;
  }

  for ( num= 0; num < fNoActiveNavigators; num++ )
  { 
    G4bool limitedStep;

    G4double step= fCurrentStepSize[num]; 

    limitedStep = ( std::fabs(step - fMinStep) < kCarTolerance ) 
                 && ( step != kInfinity); 

    fLimitTruth[ num ] = limitedStep; 
    if( limitedStep )
    {
      noLimited++;  
      fLimitedStep[num] = shared;
      last= num; 
    }
    else
    {
      fLimitedStep[num] = kDoNot;
    }
  }
  fNoGeometriesLimiting= noLimited;  // Save # processes limiting step

  if( (last > -1) && (noLimited == 1 ) )
  {
    fLimitedStep[ last ] = kUnique; 
  }

#ifdef G4DEBUG_PATHFINDER
  if( fVerboseLevel > 1 )
  {
    PrintLimited();   // --> for tracing 
    if( fVerboseLevel > 4 ) {
      G4cout << " G4PathFinder::WhichLimited - exiting. " << G4endl;
    }
  }
#endif
}

---

The documentation for this class was generated from the following files:

• G4PathFinder.hh
• G4PathFinder.cc

---