Import Geant4 9.2.0 source tree

source/geometry/navigation/src/G4AuxiliaryNavServices.cc

@@ -24,7 +24,7 @@
 // ********************************************************************
 //
 // $Id: G4AuxiliaryNavServices.cc,v 1.3 2006/06/29 18:36:32 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 

source/geometry/navigation/src/G4BrentLocator.cc

@@ -0,0 +1,736 @@
+//
+// ********************************************************************
+// * License and Disclaimer                                           *
+// *                                                                  *
+// * The  Geant4 software  is  copyright of the Copyright Holders  of *
+// * the Geant4 Collaboration.  It is provided  under  the terms  and *
+// * conditions of the Geant4 Software License,  included in the file *
+// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * include a list of copyright holders.                             *
+// *                                                                  *
+// * Neither the authors of this software system, nor their employing *
+// * institutes,nor the agencies providing financial support for this *
+// * work  make  any representation or  warranty, express or implied, *
+// * regarding  this  software system or assume any liability for its *
+// * use.  Please see the license in the file  LICENSE  and URL above *
+// * for the full disclaimer and the limitation of liability.         *
+// *                                                                  *
+// * This  code  implementation is the result of  the  scientific and *
+// * technical work of the GEANT4 collaboration.                      *
+// * By using,  copying,  modifying or  distributing the software (or *
+// * any work based  on the software)  you  agree  to acknowledge its *
+// * use  in  resulting  scientific  publications,  and indicate your *
+// * acceptance of all terms of the Geant4 Software license.          *
+// ********************************************************************
+//
+// $Id: G4BrentLocator.cc,v 1.5 2008/12/11 10:13:41 tnikitin Exp $
+// GEANT4 tag $Name: geant4-09-02 $
+//
+// Class G4BrentLocator implementation
+//
+// 27.10.08 - Tatiana Nikitina.
+// ---------------------------------------------------------------------------
+
+#include "G4BrentLocator.hh"
+#include "G4ios.hh"
+#include <iomanip>
+
+G4BrentLocator::G4BrentLocator(G4Navigator *theNavigator)
+ : G4VIntersectionLocator(theNavigator)
+{
+  // In case of too slow progress in finding Intersection Point
+  // intermediates Points on the Track must be stored.
+  // Initialise the array of Pointers [max_depth+1] to do this  
+  
+  G4ThreeVector zeroV(0.0,0.0,0.0);
+  for (G4int idepth=0; idepth<max_depth+1; idepth++ )
+  {
+    ptrInterMedFT[ idepth ] = new G4FieldTrack( zeroV, zeroV, 0., 0., 0., 0.);
+  }
+
+  // Counters for Locator
+
+  // Counter for Maximum Number Of Trial before Intersection Found
+  //
+  maxNumberOfStepsForIntersection=0;
+
+  // Counter for Number Of Calls to ReIntegrationEndPoint Method
+  //
+  maxNumberOfCallsToReIntegration=0; 
+  maxNumberOfCallsToReIntegration_depth=0; 
+}
+
+G4BrentLocator::~G4BrentLocator()
+{
+  for ( G4int idepth=0; idepth<max_depth+1; idepth++)
+  {
+    delete ptrInterMedFT[idepth];
+  }
+#ifdef G4DEBUG_FIELD
+  if(fVerboseLevel>0)
+  {
+    G4cout << "G4BrentLocator::Location with Max Number of Steps="
+           << maxNumberOfStepsForIntersection<<G4endl;
+    G4cout << "G4BrentLocator::ReIntegrateEndPoint was called "
+           << maxNumberOfCallsToReIntegration
+           << " times and for depth algorithm "
+           << maxNumberOfCallsToReIntegration_depth << " times." << G4endl;
+  }
+#endif
+}
+
+// --------------------------------------------------------------------------
+// G4bool G4PropagatorInField::LocateIntersectionPoint( 
+//        const G4FieldTrack&       CurveStartPointVelocity,   //  A
+//        const G4FieldTrack&       CurveEndPointVelocity,     //  B
+//        const G4ThreeVector&      TrialPoint,                //  E
+//              G4FieldTrack&       IntersectedOrRecalculated  // Output
+//              G4bool&             recalculated)              // Out
+// --------------------------------------------------------------------------
+//
+// Function that returns the intersection of the true path with the surface
+// of the current volume (either the external one or the inner one with one
+// of the daughters:
+//
+//     A = Initial point
+//     B = another point 
+//
+// Both A and B are assumed to be on the true path:
+//
+//     E is the first point of intersection of the chord AB with 
+//     a volume other than A  (on the surface of A or of a daughter)
+//
+// Convention of Use :
+//     i) If it returns "true", then IntersectionPointVelocity is set
+//        to the approximate intersection point.
+//    ii) If it returns "false", no intersection was found.
+//        The validity of IntersectedOrRecalculated depends on 'recalculated'
+//        a) if latter is false, then IntersectedOrRecalculated is invalid. 
+//        b) if latter is true,  then IntersectedOrRecalculated is
+//           the new endpoint, due to a re-integration.
+// --------------------------------------------------------------------------
+// NOTE: implementation taken from G4PropagatorInField
+//       New second order locator is added 
+//
+G4bool G4BrentLocator::EstimateIntersectionPoint( 
+         const  G4FieldTrack&       CurveStartPointVelocity,       // A
+         const  G4FieldTrack&       CurveEndPointVelocity,         // B
+         const  G4ThreeVector&      TrialPoint,                    // E
+                G4FieldTrack&       IntersectedOrRecalculatedFT,   // Output
+                G4bool&             recalculatedEndPoint,          // Out
+                G4double&           fPreviousSafety,               // In/Out
+                G4ThreeVector&      fPreviousSftOrigin)            // In/Out 
+              
+{   
+  // Find Intersection Point ( A, B, E )  of true path AB - start at E.
+
+  G4bool found_approximate_intersection = false;
+  G4bool there_is_no_intersection       = false;
+  
+  G4FieldTrack  CurrentA_PointVelocity = CurveStartPointVelocity; 
+  G4FieldTrack  CurrentB_PointVelocity = CurveEndPointVelocity;
+  G4ThreeVector CurrentE_Point = TrialPoint;
+  G4FieldTrack  ApproxIntersecPointV(CurveEndPointVelocity); // FT-Def-Construct
+  G4double      NewSafety = 0.0;
+  G4bool        last_AF_intersection = false; 
+
+  // G4bool final_section= true;  // Shows whether current section is last
+                                  // (i.e. B=full end)
+  G4bool first_section = true;
+  recalculatedEndPoint = false; 
+
+  G4bool restoredFullEndpoint = false;
+
+  G4int substep_no = 0;
+   
+  // Limits for substep number
+  //
+  const G4int max_substeps=   10000;  // Test 120  (old value 100 )
+  const G4int warn_substeps=   1000;  //      100  
+
+  // Statistics for substeps
+  //
+  static G4int max_no_seen= -1; 
+  static G4int trigger_substepno_print= warn_substeps - 20 ;
+
+  //--------------------------------------------------------------------------  
+  //  Algorithm for the case if progress in founding intersection is too slow.
+  //  Process is defined too slow if after N=param_substeps advances on the
+  //  path, it will be only 'fraction_done' of the total length.
+  //  In this case the remaining length is divided in two half and 
+  //  the loop is restarted for each half.  
+  //  If progress is still too slow, the division in two halfs continue
+  //  until 'max_depth'.
+  //--------------------------------------------------------------------------
+
+  const G4int param_substeps=100; // Test value for the maximum number
+                                  // of substeps
+  const G4double fraction_done=0.3;
+
+  G4bool Second_half = false;     // First half or second half of divided step
+
+  // We need to know this for the 'final_section':
+  // real 'final_section' or first half 'final_section'
+  // In algorithm it is considered that the 'Second_half' is true
+  // and it becomes false only if we are in the first-half of level
+  // depthness or if we are in the first section
+
+  G4int depth=0; // Depth counts how many subdivisions of initial step made
+
+#ifdef G4DEBUG_FIELD
+  static G4double tolerance= 1.0e-8; 
+  G4ThreeVector  StartPosition= CurveStartPointVelocity.GetPosition(); 
+  if( (TrialPoint - StartPosition).mag() < tolerance * mm ) 
+  {
+     G4cerr << "WARNING - G4BrentLocator::EstimateIntersectionPoint()"
+            << G4endl
+            << "          Intermediate F point is on top of starting point A."
+            << G4endl;
+     G4Exception("G4BrentLocator::EstimateIntersectionPoint()", 
+                 "IntersectionPointIsAtStart", JustWarning,
+                 "Intersection point F is exactly at start point A." ); 
+  }
+#endif
+
+  // Intermediates Points on the Track = Subdivided Points must be stored.
+  // Give the initial values to 'InterMedFt'
+  // Important is 'ptrInterMedFT[0]', it saves the 'EndCurvePoint'
+  //
+  *ptrInterMedFT[0] = CurveEndPointVelocity;
+  for (G4int idepth=1; idepth<max_depth+1; idepth++ )
+  {
+    *ptrInterMedFT[idepth]=CurveStartPointVelocity;
+  }
+
+  //Final_section boolean store
+  G4bool fin_section_depth[max_depth];
+  for (G4int idepth=0; idepth<max_depth; idepth++ )
+  {
+    fin_section_depth[idepth]=true;
+  }
+
+  // 'SubStartPoint' is needed to calculate the length of the divided step
+  //
+  G4FieldTrack SubStart_PointVelocity = CurveStartPointVelocity;
+   
+  do
+  {
+    G4int substep_no_p = 0;
+    G4bool sub_final_section = false; // the same as final_section,
+                                      // but for 'sub_section'
+    SubStart_PointVelocity = CurrentA_PointVelocity;
+    do // REPEAT param
+    {
+      G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();  
+      G4ThreeVector Point_B = CurrentB_PointVelocity.GetPosition();
+       
+      // F = a point on true AB path close to point E 
+      // (the closest if possible)
+      //
+      if(substep_no_p==0)
+      {
+        ApproxIntersecPointV = GetChordFinderFor()
+                               ->ApproxCurvePointV( CurrentA_PointVelocity, 
+                                                    CurrentB_PointVelocity, 
+                                                    CurrentE_Point,
+                                                    GetEpsilonStepFor());
+          //  The above method is the key & most intuitive part ...
+      }
+#ifdef G4DEBUG_FIELD
+      if( ApproxIntersecPointV.GetCurveLength() > 
+          CurrentB_PointVelocity.GetCurveLength() * (1.0 + tolerance) )
+      {
+        G4cerr << "ERROR - G4BrentLocator::EstimateIntersectionPoint()"
+               << G4endl
+               << "        Intermediate F point is more advanced than"
+               << " endpoint B." << G4endl;
+        G4Exception("G4BrentLocator::EstimateIntersectionPoint()", 
+                    "IntermediatePointConfusion", FatalException,
+                    "Intermediate F point is past end B point" ); 
+      }
+#endif
+
+      G4ThreeVector CurrentF_Point= ApproxIntersecPointV.GetPosition();
+
+      // First check whether EF is small - then F is a good approx. point 
+      // Calculate the length and direction of the chord AF
+      //
+      G4ThreeVector  ChordEF_Vector = CurrentF_Point - CurrentE_Point;
+
+      if ( ChordEF_Vector.mag2() <= sqr(GetDeltaIntersectionFor()) )
+      {
+        found_approximate_intersection = true;
+    
+        // Create the "point" return value
+        //
+        IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+        IntersectedOrRecalculatedFT.SetPosition( CurrentE_Point );
+        
+        if ( GetAdjustementOfFoundIntersection() )
+        {
+          // Try to Get Correction of IntersectionPoint using SurfaceNormal()
+          //  
+          G4ThreeVector IP;
+          G4ThreeVector MomentumDir=ApproxIntersecPointV.GetMomentumDirection();
+          G4bool goodCorrection = AdjustmentOfFoundIntersection( Point_A,
+                                    CurrentE_Point, CurrentF_Point, MomentumDir,
+                                    last_AF_intersection, IP, NewSafety,
+                                    fPreviousSafety, fPreviousSftOrigin );
+          if ( goodCorrection )
+          {
+            IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+            IntersectedOrRecalculatedFT.SetPosition(IP);
+          }
+        }
+       
+        // Note: in order to return a point on the boundary, 
+        //       we must return E. But it is F on the curve.
+        //       So we must "cheat": we are using the position at point E
+        //       and the velocity at point F !!!
+        //
+        // This must limit the length we can allow for displacement!
+      }
+      else  // E is NOT close enough to the curve (ie point F)
+      {
+        // Check whether any volumes are encountered by the chord AF
+        // ---------------------------------------------------------
+        // First relocate to restore any Voxel etc information
+        // in the Navigator before calling ComputeStep()
+        //
+        GetNavigatorFor()->LocateGlobalPointWithinVolume( Point_A );
+
+        G4ThreeVector PointG;   // Candidate intersection point
+        G4double stepLengthAF; 
+        G4bool Intersects_AF = IntersectChord( Point_A,   CurrentF_Point,
+                                               NewSafety,fPreviousSafety,
+                                               fPreviousSftOrigin,
+                                               stepLengthAF,
+                                               PointG );
+        last_AF_intersection = Intersects_AF;
+        if( Intersects_AF )
+        {
+          // G is our new Candidate for the intersection point.
+          // It replaces  "E" and we will repeat the test to see if
+          // it is a good enough approximate point for us.
+          //       B    <- F
+          //       E    <- G
+          //
+          G4FieldTrack EndPoint = ApproxIntersecPointV;
+          ApproxIntersecPointV = GetChordFinderFor()->ApproxCurvePointS(
+                                 CurrentA_PointVelocity, CurrentB_PointVelocity,
+                                 EndPoint,CurrentE_Point, CurrentF_Point,PointG,
+                                 true, GetEpsilonStepFor() );
+          CurrentB_PointVelocity = EndPoint;
+          CurrentE_Point = PointG;
+            
+          // By moving point B, must take care if current
+          // AF has no intersection to try current FB!!
+          //
+          fin_section_depth[depth] = false;
+#ifdef G4VERBOSE
+          if( fVerboseLevel > 3 )
+          {
+            G4cout << "G4PiF::LI> Investigating intermediate point"
+                   << " at s=" << ApproxIntersecPointV.GetCurveLength()
+                   << " on way to full s="
+                   << CurveEndPointVelocity.GetCurveLength() << G4endl;
+          }
+#endif
+        }
+        else  // not Intersects_AF
+        {  
+          // In this case:
+          // There is NO intersection of AF with a volume boundary.
+          // We must continue the search in the segment FB!
+          //
+          GetNavigatorFor()->LocateGlobalPointWithinVolume( CurrentF_Point );
+
+          G4double stepLengthFB;
+          G4ThreeVector PointH;
+
+          // Check whether any volumes are encountered by the chord FB
+          // ---------------------------------------------------------
+
+          G4bool Intersects_FB = IntersectChord( CurrentF_Point, Point_B, 
+                                                 NewSafety,fPreviousSafety,
+                                                 fPreviousSftOrigin,
+                                                 stepLengthFB,
+                                                 PointH );
+          if( Intersects_FB )
+          { 
+            // There is an intersection of FB with a volume boundary
+            // H <- First Intersection of Chord FB 
+
+            // H is our new Candidate for the intersection point.
+            // It replaces  "E" and we will repeat the test to see if
+            // it is a good enough approximate point for us.
+
+            // Note that F must be in volume volA  (the same as A)
+            // (otherwise AF would meet a volume boundary!)
+            //   A    <- F 
+            //   E    <- H
+            //
+            CurrentA_PointVelocity = ApproxIntersecPointV;
+            ApproxIntersecPointV = GetChordFinderFor()->ApproxCurvePointS(
+                          CurrentA_PointVelocity,CurrentB_PointVelocity,
+                          CurrentA_PointVelocity,CurrentE_Point,Point_A,PointH,
+                          false,GetEpsilonStepFor());
+            CurrentE_Point = PointH;
+          }
+          else  // not Intersects_FB
+          {
+            // There is NO intersection of FB with a volume boundary
+
+            if( fin_section_depth[depth]  )
+            { 
+              // If B is the original endpoint, this means that whatever
+              // volume(s) intersected the original chord, none touch the
+              // smaller chords we have used.
+              // The value of 'IntersectedOrRecalculatedFT' returned is
+              // likely not valid 
+
+              // Check on real final_section or SubEndSection
+              //
+              if( ((Second_half)&&(depth==0)) || (first_section) )
+              {
+                there_is_no_intersection = true;   // real final_section
+              }
+              else
+              {
+                // end of subsection, not real final section 
+                // exit from the and go to the depth-1 level 
+
+                substep_no_p = param_substeps+2;  // exit from the loop
+
+                // but 'Second_half' is still true because we need to find
+                // the 'CurrentE_point' for the next loop
+                //
+                Second_half = true; 
+                sub_final_section = true;
+              }
+            }
+            else
+            {
+              if(depth==0)
+              {
+                // We must restore the original endpoint
+                //
+                CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
+                CurrentB_PointVelocity = CurveEndPointVelocity;
+                SubStart_PointVelocity = CurrentA_PointVelocity;
+                restoredFullEndpoint = true;
+              }
+              else
+              {
+                // We must restore the depth endpoint
+                //
+                CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
+                CurrentB_PointVelocity =  *ptrInterMedFT[depth];
+                SubStart_PointVelocity = CurrentA_PointVelocity;
+                restoredFullEndpoint = true;
+              }
+            }
+          } // Endif (Intersects_FB)
+        } // Endif (Intersects_AF)
+
+        // Ensure that the new endpoints are not further apart in space
+        // than on the curve due to different errors in the integration
+        //
+        G4double linDistSq, curveDist; 
+        linDistSq = ( CurrentB_PointVelocity.GetPosition() 
+                    - CurrentA_PointVelocity.GetPosition() ).mag2(); 
+        curveDist = CurrentB_PointVelocity.GetCurveLength()
+                    - CurrentA_PointVelocity.GetCurveLength();
+
+        // Change this condition for very strict parameters of propagation 
+        //
+        if( curveDist*curveDist*(1+2* GetEpsilonStepFor()) < linDistSq )
+        {
+          // Re-integrate to obtain a new B
+          //
+          G4FieldTrack newEndPointFT=
+                  ReEstimateEndpoint( CurrentA_PointVelocity,
+                                      CurrentB_PointVelocity,
+                                      linDistSq,    // to avoid recalculation
+                                      curveDist );
+          G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
+          CurrentB_PointVelocity = newEndPointFT;
+         
+          if ( (fin_section_depth[depth])           // real final section
+             &&( first_section  || ((Second_half)&&(depth==0)) ) )
+          {
+            recalculatedEndPoint = true;
+            IntersectedOrRecalculatedFT = newEndPointFT;
+              // So that we can return it, if it is the endpoint!
+          }
+        }
+        if( curveDist < 0.0 )
+        {
+          G4cerr << "ERROR - G4BrentLocator::EstimateIntersectionPoint()"
+                 << G4endl
+                 << "        Error in advancing propagation." << G4endl;
+          fVerboseLevel = 5; // Print out a maximum of information
+          printStatus( CurrentA_PointVelocity,  CurrentB_PointVelocity,
+                       -1.0, NewSafety,  substep_no );
+          G4cerr << "        Point A (start) is " << CurrentA_PointVelocity
+                 << G4endl;
+          G4cerr << "        Point B (end)   is " << CurrentB_PointVelocity
+                 << G4endl;
+          G4cerr << "        Curve distance is " << curveDist << G4endl;
+          G4cerr << G4endl
+                 << "The final curve point is not further along"
+                 << " than the original!" << G4endl;
+
+          if( recalculatedEndPoint )
+          {
+            G4cerr << "Recalculation of EndPoint was called with fEpsStep= "
+                   << GetEpsilonStepFor() << G4endl;
+          }
+          G4cerr.precision(20);
+          G4cerr << " Point A (Curve start)   is " << CurveStartPointVelocity
+                 << G4endl;
+          G4cerr << " Point B (Curve   end)   is " << CurveEndPointVelocity
+                 << G4endl;
+          G4cerr << " Point A (Current start) is " << CurrentA_PointVelocity
+                 << G4endl;
+          G4cerr << " Point B (Current end)   is " << CurrentB_PointVelocity
+                 << G4endl;
+          G4cerr << " Point S (Sub start)     is " << SubStart_PointVelocity
+                 << G4endl;
+          G4cerr << " Point E (Trial Point)   is " << CurrentE_Point
+                 << G4endl;
+          G4cerr << " Point F (Intersection)  is " << ApproxIntersecPointV
+                 << G4endl;
+          G4cerr << "        LocateIntersection parameters are : Substep no= "
+                 << substep_no << G4endl;
+          G4cerr << "        Substep depth no= "<< substep_no_p  << " Depth= "
+                 << depth << G4endl;
+
+          G4Exception("G4BrentLocator::EstimateIntersectionPoint()",
+                      "FatalError", FatalException,
+                      "Error in advancing propagation.");
+        }
+
+        if(restoredFullEndpoint)
+        {
+          fin_section_depth[depth] = restoredFullEndpoint;
+          restoredFullEndpoint = false;
+        }
+      } // EndIf ( E is close enough to the curve, ie point F. )
+        // tests ChordAF_Vector.mag() <= maximum_lateral_displacement 
+
+#ifdef G4DEBUG_LOCATE_INTERSECTION  
+      if( substep_no >= trigger_substepno_print )
+      {
+        G4cout << "Difficulty in converging in "
+               << "G4BrentLocator::EstimateIntersectionPoint()"
+               << G4endl
+               << "    Substep no = " << substep_no << G4endl;
+        if( substep_no == trigger_substepno_print )
+        {
+          printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                       -1.0, NewSafety, 0);
+        }
+        G4cout << " State of point A: "; 
+        printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                     -1.0, NewSafety, substep_no-1, 0);
+        G4cout << " State of point B: "; 
+        printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                     -1.0, NewSafety, substep_no);
+      }
+#endif
+      substep_no++; 
+      substep_no_p++;
+
+    } while (  ( ! found_approximate_intersection )
+            && ( ! there_is_no_intersection )     
+            && ( substep_no_p <= param_substeps) );  // UNTIL found or
+                                                     // failed param substep
+    first_section = false;
+
+    if( (!found_approximate_intersection) && (!there_is_no_intersection) )
+    {
+      G4double did_len = std::abs( CurrentA_PointVelocity.GetCurveLength()
+                       - SubStart_PointVelocity.GetCurveLength()); 
+      G4double all_len = std::abs( CurrentB_PointVelocity.GetCurveLength()
+                       - SubStart_PointVelocity.GetCurveLength());
+   
+      G4double stepLengthAB;
+      G4ThreeVector PointGe;
+
+      // Check if progress is too slow and if it possible to go deeper,
+      // then halve the step if so
+      //
+      if ( ( did_len < fraction_done*all_len )
+        && (depth<max_depth) && (!sub_final_section) )
+      {
+        Second_half=false;
+        depth++;
+
+        G4double Sub_len = (all_len-did_len)/(2.);
+        G4FieldTrack start = CurrentA_PointVelocity;
+        G4MagInt_Driver* integrDriver =
+                         GetChordFinderFor()->GetIntegrationDriver();
+        integrDriver->AccurateAdvance(start, Sub_len, GetEpsilonStepFor());
+        *ptrInterMedFT[depth] = start;
+        CurrentB_PointVelocity = *ptrInterMedFT[depth];
+ 
+        // Adjust 'SubStartPoint' to calculate the 'did_length' in next loop
+        //
+        SubStart_PointVelocity = CurrentA_PointVelocity;
+
+        // Find new trial intersection point needed at start of the loop
+        //
+        G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();
+        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
+     
+        GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
+        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point,
+                                              NewSafety, fPreviousSafety,
+                                              fPreviousSftOrigin,stepLengthAB,
+                                              PointGe);
+        if( Intersects_AB )
+        {
+          last_AF_intersection = Intersects_AB;
+          CurrentE_Point = PointGe;
+          fin_section_depth[depth]=true;
+        }
+        else
+        {
+          // No intersection found for first part of curve
+          // (CurrentA,InterMedPoint[depth]). Go to the second part
+          //
+          Second_half = true;
+        }
+      } // if did_len
+
+      if( (Second_half)&&(depth!=0) )
+      {
+        // Second part of curve (InterMed[depth],Intermed[depth-1])                       ) 
+        // On the depth-1 level normally we are on the 'second_half'
+
+        Second_half = true;
+
+        //  Find new trial intersection point needed at start of the loop
+        //
+        SubStart_PointVelocity = *ptrInterMedFT[depth];
+        CurrentA_PointVelocity = *ptrInterMedFT[depth];
+        CurrentB_PointVelocity = *ptrInterMedFT[depth-1];
+         // Ensure that the new endpoints are not further apart in space
+        // than on the curve due to different errors in the integration
+        //
+        G4double linDistSq, curveDist; 
+        linDistSq = ( CurrentB_PointVelocity.GetPosition() 
+                    - CurrentA_PointVelocity.GetPosition() ).mag2(); 
+        curveDist = CurrentB_PointVelocity.GetCurveLength()
+                    - CurrentA_PointVelocity.GetCurveLength();
+        if( curveDist*curveDist*(1+2*GetEpsilonStepFor() ) < linDistSq )
+        {
+          // Re-integrate to obtain a new B
+          //
+          G4FieldTrack newEndPointFT=
+                  ReEstimateEndpoint( CurrentA_PointVelocity,
+                                      CurrentB_PointVelocity,
+                                      linDistSq,    // to avoid recalculation
+                                      curveDist );
+          G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
+          CurrentB_PointVelocity = newEndPointFT;
+          if (depth==1)
+          {
+            recalculatedEndPoint = true;
+            IntersectedOrRecalculatedFT = newEndPointFT;
+            // So that we can return it, if it is the endpoint!
+          }
+        }
+
+
+        G4ThreeVector Point_A    = CurrentA_PointVelocity.GetPosition();
+        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
+        GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
+        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point, NewSafety,
+                                              fPreviousSafety,
+                                               fPreviousSftOrigin,stepLengthAB, PointGe);
+        if( Intersects_AB )
+        {
+          last_AF_intersection = Intersects_AB;
+          CurrentE_Point = PointGe;
+        }
+       
+        depth--;
+        fin_section_depth[depth]=true;
+      }
+    }  // if(!found_aproximate_intersection)
+
+  } while ( ( ! found_approximate_intersection )
+            && ( ! there_is_no_intersection )     
+            && ( substep_no <= max_substeps) ); // UNTIL found or failed
+
+  if( substep_no > max_no_seen )
+  {
+    max_no_seen = substep_no; 
+    if( max_no_seen > warn_substeps )
+    {
+      trigger_substepno_print = max_no_seen-20; // Want to see last 20 steps 
+    } 
+  }
+
+  if(  ( substep_no >= max_substeps)
+      && !there_is_no_intersection
+      && !found_approximate_intersection )
+  {
+    G4cerr << "WARNING - G4BrentLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cerr << "          Abandoning effort to intersect. " << G4endl;
+    G4cerr << "          Information on start & current step follows in cout."
+           << G4endl;
+    G4cout << "WARNING - G4BrentLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cout << "          Found intersection = "
+           << found_approximate_intersection << G4endl
+           << "          Intersection exists = "
+           << !there_is_no_intersection << G4endl;
+    G4cout << "          Start and Endpoint of Requested Step:" << G4endl;
+    printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                 -1.0, NewSafety, 0);
+    G4cout << G4endl;
+    G4cout << "          'Bracketing' starting and endpoint of current Sub-Step"
+           << G4endl;
+    printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                 -1.0, NewSafety, substep_no-1);
+    printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                 -1.0, NewSafety, substep_no);
+    G4cout << G4endl;
+    G4cout.precision( 10 ); 
+    G4double done_len = CurrentA_PointVelocity.GetCurveLength(); 
+    G4double full_len = CurveEndPointVelocity.GetCurveLength();
+    G4cout << "ERROR - G4BrentLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "        Undertaken only length: " << done_len
+           << " out of " << full_len << " required." << G4endl;
+    G4cout << "        Remaining length = " << full_len - done_len << G4endl; 
+
+    G4Exception("G4BrentLocator::EstimateIntersectionPoint()",
+                "UnableToLocateIntersection", FatalException,
+                "Too many substeps while trying to locate intersection.");
+  }
+  else if( substep_no >= warn_substeps )
+  {  
+    G4int oldprc= G4cout.precision( 10 ); 
+    G4cout << "WARNING - G4BrentLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Undertaken length: "  
+           << CurrentB_PointVelocity.GetCurveLength(); 
+    G4cout << " - Needed: "  << substep_no << " substeps." << G4endl
+           << "          Warning level = " << warn_substeps
+           << " and maximum substeps = " << max_substeps << G4endl;
+    G4Exception("G4BrentLocator::EstimateIntersectionPoint()",
+                "DifficultyToLocateIntersection", JustWarning,
+                "Many substeps while trying to locate intersection.");
+    G4cout.precision( oldprc ); 
+  }
+  return  !there_is_no_intersection; //  Success or failure
+}

source/geometry/navigation/src/G4DrawVoxels.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4DrawVoxels.cc,v 1.4 2006/06/29 18:36:34 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // 
 // class G4DrawVoxels

source/geometry/navigation/src/G4ErrorPropagationNavigator.cc

@@ -24,8 +24,8 @@
 // ********************************************************************
 //
 //
-// $Id: G4ErrorPropagationNavigator.cc,v 1.1 2007/05/16 12:49:18 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// $Id: G4ErrorPropagationNavigator.cc,v 1.2 2008/10/24 14:00:03 gcosmo Exp $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // --------------------------------------------------------------------
@@ -125,9 +125,11 @@ ComputeStep ( const G4ThreeVector &pGlobalPoint,
 
 G4double G4ErrorPropagationNavigator::
 ComputeSafety( const G4ThreeVector &pGlobalpoint,
-               const G4double pMaxLength )
+               const G4double pMaxLength,
+               const G4bool keepState )
 {
-  G4double newSafety = G4Navigator::ComputeSafety(pGlobalpoint, pMaxLength);
+  G4double newSafety = G4Navigator::ComputeSafety(pGlobalpoint,
+                                                  pMaxLength, keepState);
 
   G4ErrorPropagatorData *g4edata
     = G4ErrorPropagatorData::GetErrorPropagatorData();

source/geometry/navigation/src/G4GeomTestErrorList.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestErrorList.cc,v 1.3 2006/06/29 18:36:36 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestOverlapList.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestOverlapList.cc,v 1.3 2006/06/29 18:36:39 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestOvershootList.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestOvershootList.cc,v 1.3 2006/06/29 18:36:41 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestPoint.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestPoint.cc,v 1.3 2006/06/29 18:36:44 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestSegment.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestSegment.cc,v 1.11 2007/11/16 09:39:14 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestStreamLogger.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestStreamLogger.cc,v 1.3 2006/06/29 18:36:49 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestVolPoint.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestVolPoint.cc,v 1.3 2006/06/29 18:36:52 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeomTestVolume.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeomTestVolume.cc,v 1.6 2007/11/16 09:39:14 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4GeometryMessenger.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4GeometryMessenger.cc,v 1.5 2006/06/29 18:36:57 gunter Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 // --------------------------------------------------------------------
 // GEANT 4 class source file

source/geometry/navigation/src/G4MultiLevelLocator.cc

@@ -0,0 +1,722 @@
+//
+// ********************************************************************
+// * License and Disclaimer                                           *
+// *                                                                  *
+// * The  Geant4 software  is  copyright of the Copyright Holders  of *
+// * the Geant4 Collaboration.  It is provided  under  the terms  and *
+// * conditions of the Geant4 Software License,  included in the file *
+// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * include a list of copyright holders.                             *
+// *                                                                  *
+// * Neither the authors of this software system, nor their employing *
+// * institutes,nor the agencies providing financial support for this *
+// * work  make  any representation or  warranty, express or implied, *
+// * regarding  this  software system or assume any liability for its *
+// * use.  Please see the license in the file  LICENSE  and URL above *
+// * for the full disclaimer and the limitation of liability.         *
+// *                                                                  *
+// * This  code  implementation is the result of  the  scientific and *
+// * technical work of the GEANT4 collaboration.                      *
+// * By using,  copying,  modifying or  distributing the software (or *
+// * any work based  on the software)  you  agree  to acknowledge its *
+// * use  in  resulting  scientific  publications,  and indicate your *
+// * acceptance of all terms of the Geant4 Software license.          *
+// ********************************************************************
+//
+// $Id: G4MultiLevelLocator.cc,v 1.5 2008/12/11 10:01:02 tnikitin Exp $
+// GEANT4 tag $Name: geant4-09-02 $
+//
+// Class G4MultiLevelLocator implementation
+//
+// 27.10.08 - Tatiana Nikitina.
+// ---------------------------------------------------------------------------
+
+#include <iomanip>
+
+#include "G4ios.hh"
+#include "G4MultiLevelLocator.hh"
+
+G4MultiLevelLocator::G4MultiLevelLocator(G4Navigator *theNavigator)
+ : G4VIntersectionLocator(theNavigator)
+{
+  // In case of too slow progress in finding Intersection Point
+  // intermediates Points on the Track must be stored.
+  // Initialise the array of Pointers [max_depth+1] to do this  
+  
+  G4ThreeVector zeroV(0.0,0.0,0.0);
+  for (G4int idepth=0; idepth<max_depth+1; idepth++ )
+  {
+    ptrInterMedFT[ idepth ] = new G4FieldTrack( zeroV, zeroV, 0., 0., 0., 0.);
+  }
+}      
+
+G4MultiLevelLocator::~G4MultiLevelLocator()
+{
+  for ( G4int idepth=0; idepth<max_depth+1; idepth++)
+  {
+    delete ptrInterMedFT[idepth];
+  }
+}
+
+// --------------------------------------------------------------------------
+// G4bool G4PropagatorInField::LocateIntersectionPoint( 
+//        const G4FieldTrack&       CurveStartPointVelocity,   // A
+//        const G4FieldTrack&       CurveEndPointVelocity,     // B
+//        const G4ThreeVector&      TrialPoint,                // E
+//              G4FieldTrack&       IntersectedOrRecalculated  // Output
+//              G4bool&             recalculated )             // Out
+// --------------------------------------------------------------------------
+//
+// Function that returns the intersection of the true path with the surface
+// of the current volume (either the external one or the inner one with one
+// of the daughters:
+//
+//     A = Initial point
+//     B = another point 
+//
+// Both A and B are assumed to be on the true path:
+//
+//     E is the first point of intersection of the chord AB with 
+//     a volume other than A  (on the surface of A or of a daughter)
+//
+// Convention of Use :
+//     i) If it returns "true", then IntersectionPointVelocity is set
+//       to the approximate intersection point.
+//    ii) If it returns "false", no intersection was found.
+//          The validity of IntersectedOrRecalculated depends on 'recalculated'
+//        a) if latter is false, then IntersectedOrRecalculated is invalid. 
+//        b) if latter is true,  then IntersectedOrRecalculated is
+//             the new endpoint, due to a re-integration.
+// --------------------------------------------------------------------------
+// NOTE: implementation taken from G4PropagatorInField
+//
+G4bool G4MultiLevelLocator::EstimateIntersectionPoint( 
+         const  G4FieldTrack&       CurveStartPointVelocity,       // A
+         const  G4FieldTrack&       CurveEndPointVelocity,         // B
+         const  G4ThreeVector&      TrialPoint,                    // E
+                G4FieldTrack&       IntersectedOrRecalculatedFT,   // Output
+                G4bool&             recalculatedEndPoint,          // Out
+                G4double            &fPreviousSafety,              // In/Out
+                G4ThreeVector       &fPreviousSftOrigin)           // In/Out
+{
+  // Find Intersection Point ( A, B, E )  of true path AB - start at E.
+
+  G4bool found_approximate_intersection = false;
+  G4bool there_is_no_intersection       = false;
+  
+  G4FieldTrack  CurrentA_PointVelocity = CurveStartPointVelocity; 
+  G4FieldTrack  CurrentB_PointVelocity = CurveEndPointVelocity;
+  G4ThreeVector CurrentE_Point = TrialPoint;
+  G4FieldTrack  ApproxIntersecPointV(CurveEndPointVelocity); // FT-Def-Construct
+  G4double      NewSafety = 0.0;
+  G4bool        last_AF_intersection = false;   
+
+  // G4bool final_section= true;  // Shows whether current section is last
+                                  // (i.e. B=full end)
+  G4bool first_section = true;
+  recalculatedEndPoint = false; 
+
+  G4bool restoredFullEndpoint = false;
+
+  G4int substep_no = 0;
+   
+  // Limits for substep number
+  //
+  const G4int max_substeps=   10000;  // Test 120  (old value 100 )
+  const G4int warn_substeps=   1000;  //      100  
+
+  // Statistics for substeps
+  //
+  static G4int max_no_seen= -1; 
+  static G4int trigger_substepno_print= warn_substeps - 20 ;
+
+  //--------------------------------------------------------------------------  
+  //  Algorithm for the case if progress in founding intersection is too slow.
+  //  Process is defined too slow if after N=param_substeps advances on the
+  //  path, it will be only 'fraction_done' of the total length.
+  //  In this case the remaining length is divided in two half and 
+  //  the loop is restarted for each half.  
+  //  If progress is still too slow, the division in two halfs continue
+  //  until 'max_depth'.
+  //--------------------------------------------------------------------------
+
+  const G4int param_substeps=10; // Test value for the maximum number
+                                 // of substeps
+  const G4double fraction_done=0.3;
+
+  G4bool Second_half = false;    // First half or second half of divided step
+
+  // We need to know this for the 'final_section':
+  // real 'final_section' or first half 'final_section'
+  // In algorithm it is considered that the 'Second_half' is true
+  // and it becomes false only if we are in the first-half of level
+  // depthness or if we are in the first section
+
+  G4int depth=0; // Depth counts how many subdivisions of initial step made
+
+#ifdef G4DEBUG_FIELD
+  static G4double tolerance= 1.0e-8; 
+  G4ThreeVector  StartPosition= CurveStartPointVelocity.GetPosition(); 
+  if( (TrialPoint - StartPosition).mag() < tolerance * mm ) 
+  {
+     G4cerr << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
+            << G4endl
+            << "          Intermediate F point is on top of starting point A."
+            << G4endl;
+     G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()", 
+                 "IntersectionPointIsAtStart", JustWarning,
+                 "Intersection point F is exactly at start point A." ); 
+  }
+#endif
+
+  // Intermediates Points on the Track = Subdivided Points must be stored.
+  // Give the initial values to 'InterMedFt'
+  // Important is 'ptrInterMedFT[0]', it saves the 'EndCurvePoint'
+  //
+  *ptrInterMedFT[0] = CurveEndPointVelocity;
+  for (G4int idepth=1; idepth<max_depth+1; idepth++ )
+  {
+    *ptrInterMedFT[idepth]=CurveStartPointVelocity;
+  }
+
+  // Final_section boolean store
+  //
+  G4bool fin_section_depth[max_depth];
+  for (G4int idepth=0; idepth<max_depth; idepth++ )
+  {
+    fin_section_depth[idepth]=true;
+  }
+  // 'SubStartPoint' is needed to calculate the length of the divided step
+  //
+  G4FieldTrack SubStart_PointVelocity = CurveStartPointVelocity;
+   
+  do
+  {
+    G4int substep_no_p = 0;
+    G4bool sub_final_section = false; // the same as final_section,
+                                      // but for 'sub_section'
+    SubStart_PointVelocity = CurrentA_PointVelocity; 
+    do // REPEAT param
+    {
+      G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();  
+      G4ThreeVector Point_B = CurrentB_PointVelocity.GetPosition();
+       
+      // F = a point on true AB path close to point E 
+      // (the closest if possible)
+      //
+      ApproxIntersecPointV = GetChordFinderFor()
+                             ->ApproxCurvePointV( CurrentA_PointVelocity, 
+                                                  CurrentB_PointVelocity, 
+                                                  CurrentE_Point,
+                                                  GetEpsilonStepFor());
+        // The above method is the key & most intuitive part ...
+     
+#ifdef G4DEBUG_FIELD
+      if( ApproxIntersecPointV.GetCurveLength() > 
+          CurrentB_PointVelocity.GetCurveLength() * (1.0 + tolerance) )
+      {
+        G4cerr << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
+               << G4endl
+               << "        Intermediate F point is more advanced than"
+               << " endpoint B." << G4endl;
+        G4Exception("G4multiLevelLocator::EstimateIntersectionPoint()", 
+                    "IntermediatePointConfusion", FatalException,
+                    "Intermediate F point is past end B point" ); 
+      }
+#endif
+
+      G4ThreeVector CurrentF_Point= ApproxIntersecPointV.GetPosition();
+
+      // First check whether EF is small - then F is a good approx. point 
+      // Calculate the length and direction of the chord AF
+      //
+      G4ThreeVector  ChordEF_Vector = CurrentF_Point - CurrentE_Point;
+
+      if ( ChordEF_Vector.mag2() <= sqr(GetDeltaIntersectionFor()) )
+      { 
+        found_approximate_intersection = true;
+
+        // Create the "point" return value
+        //
+        IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+        IntersectedOrRecalculatedFT.SetPosition( CurrentE_Point );
+
+        if ( GetAdjustementOfFoundIntersection() )
+        {
+          // Try to Get Correction of IntersectionPoint using SurfaceNormal()
+          //  
+          G4ThreeVector IP;
+          G4ThreeVector MomentumDir=ApproxIntersecPointV.GetMomentumDirection();
+          G4bool goodCorrection = AdjustmentOfFoundIntersection(Point_A,
+                                    CurrentE_Point, CurrentF_Point, MomentumDir,
+                                    last_AF_intersection, IP, NewSafety,
+                                    fPreviousSafety, fPreviousSftOrigin );
+          if ( goodCorrection )
+          {
+            IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+            IntersectedOrRecalculatedFT.SetPosition(IP);
+          }
+        }
+        // Note: in order to return a point on the boundary, 
+        //       we must return E. But it is F on the curve.
+        //       So we must "cheat": we are using the position at point E
+        //       and the velocity at point F !!!
+        //
+        // This must limit the length we can allow for displacement!
+      }
+      else  // E is NOT close enough to the curve (ie point F)
+      {
+        // Check whether any volumes are encountered by the chord AF
+        // ---------------------------------------------------------
+        // First relocate to restore any Voxel etc information
+        // in the Navigator before calling ComputeStep()
+        //
+        GetNavigatorFor()->LocateGlobalPointWithinVolume( Point_A );
+
+        G4ThreeVector PointG;   // Candidate intersection point
+        G4double stepLengthAF; 
+        G4bool Intersects_AF = IntersectChord( Point_A,   CurrentF_Point,
+                                               NewSafety,fPreviousSafety,
+                                               fPreviousSftOrigin,
+                                               stepLengthAF,
+                                               PointG );
+        last_AF_intersection = Intersects_AF;
+        if( Intersects_AF )
+        {
+          // G is our new Candidate for the intersection point.
+          // It replaces  "E" and we will repeat the test to see if
+          // it is a good enough approximate point for us.
+          //       B    <- F
+          //       E    <- G
+          //
+          CurrentB_PointVelocity = ApproxIntersecPointV;
+          CurrentE_Point = PointG;  
+
+          // By moving point B, must take care if current
+          // AF has no intersection to try current FB!!
+          //
+          fin_section_depth[depth]=false;
+          
+          
+#ifdef G4VERBOSE
+          if( fVerboseLevel > 3 )
+          {
+            G4cout << "G4PiF::LI> Investigating intermediate point"
+                   << " at s=" << ApproxIntersecPointV.GetCurveLength()
+                   << " on way to full s="
+                   << CurveEndPointVelocity.GetCurveLength() << G4endl;
+          }
+#endif
+        }
+        else  // not Intersects_AF
+        {  
+          // In this case:
+          // There is NO intersection of AF with a volume boundary.
+          // We must continue the search in the segment FB!
+          //
+          GetNavigatorFor()->LocateGlobalPointWithinVolume( CurrentF_Point );
+
+          G4double stepLengthFB;
+          G4ThreeVector PointH;
+
+          // Check whether any volumes are encountered by the chord FB
+          // ---------------------------------------------------------
+
+          G4bool Intersects_FB = IntersectChord( CurrentF_Point, Point_B, 
+                                                 NewSafety,fPreviousSafety,
+                                                 fPreviousSftOrigin,
+                                                 stepLengthFB,
+                                                 PointH );
+          if( Intersects_FB )
+          {
+            // There is an intersection of FB with a volume boundary
+            // H <- First Intersection of Chord FB 
+
+            // H is our new Candidate for the intersection point.
+            // It replaces  "E" and we will repeat the test to see if
+            // it is a good enough approximate point for us.
+
+            // Note that F must be in volume volA  (the same as A)
+            // (otherwise AF would meet a volume boundary!)
+            //   A    <- F 
+            //   E    <- H
+            //
+            CurrentA_PointVelocity = ApproxIntersecPointV;
+            CurrentE_Point = PointH;
+          }
+          else  // not Intersects_FB
+          {
+            // There is NO intersection of FB with a volume boundary
+
+            if(fin_section_depth[depth])
+            {
+              // If B is the original endpoint, this means that whatever
+              // volume(s) intersected the original chord, none touch the
+              // smaller chords we have used.
+              // The value of 'IntersectedOrRecalculatedFT' returned is
+              // likely not valid 
+
+              // Check on real final_section or SubEndSection
+              //
+              if( ((Second_half)&&(depth==0)) || (first_section) )
+              {
+                there_is_no_intersection = true;   // real final_section
+              }
+              else
+              {
+                // end of subsection, not real final section 
+                // exit from the and go to the depth-1 level 
+
+                substep_no_p = param_substeps+2;  // exit from the loop
+
+                // but 'Second_half' is still true because we need to find
+                // the 'CurrentE_point' for the next loop
+                //
+                Second_half = true; 
+                sub_final_section = true;
+                
+              }
+            }
+            else
+            {
+              if(depth==0)
+              {
+                // We must restore the original endpoint
+                //
+                CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
+                CurrentB_PointVelocity = CurveEndPointVelocity;
+                SubStart_PointVelocity = CurrentA_PointVelocity;
+                restoredFullEndpoint = true;
+              }
+              else
+              {
+                // We must restore the depth endpoint
+                //
+                CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
+                CurrentB_PointVelocity =  *ptrInterMedFT[depth];
+                SubStart_PointVelocity = CurrentA_PointVelocity;
+                restoredFullEndpoint = true;
+              }
+            }
+          } // Endif (Intersects_FB)
+        } // Endif (Intersects_AF)
+
+        // Ensure that the new endpoints are not further apart in space
+        // than on the curve due to different errors in the integration
+        //
+        G4double linDistSq, curveDist; 
+        linDistSq = ( CurrentB_PointVelocity.GetPosition() 
+                    - CurrentA_PointVelocity.GetPosition() ).mag2(); 
+        curveDist = CurrentB_PointVelocity.GetCurveLength()
+                    - CurrentA_PointVelocity.GetCurveLength();
+
+        // Change this condition for very strict parameters of propagation 
+        //
+        if( curveDist*curveDist*(1+2* GetEpsilonStepFor()) < linDistSq )
+        {  
+          // Re-integrate to obtain a new B
+          //
+          G4FieldTrack newEndPointFT=
+                  ReEstimateEndpoint( CurrentA_PointVelocity,
+                                      CurrentB_PointVelocity,
+                                      linDistSq,    // to avoid recalculation
+                                      curveDist );
+          G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
+          CurrentB_PointVelocity = newEndPointFT;
+           
+          if ( (fin_section_depth[depth])           // real final section
+             &&( first_section || ((Second_half)&&(depth==0)) ) )
+          {
+            recalculatedEndPoint = true;
+            IntersectedOrRecalculatedFT = newEndPointFT;
+              // So that we can return it, if it is the endpoint!
+          }
+        }
+        if( curveDist < 0.0 )
+        {
+          G4cerr << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
+                 << G4endl
+                 << "        Error in advancing propagation." << G4endl;
+          fVerboseLevel = 5; // Print out a maximum of information
+          printStatus( CurrentA_PointVelocity,  CurrentB_PointVelocity,
+                       -1.0, NewSafety,  substep_no );
+          G4cerr << "        Point A (start) is " << CurrentA_PointVelocity
+                 << G4endl;
+          G4cerr << "        Point B (end)   is " << CurrentB_PointVelocity
+                 << G4endl;
+          G4cerr << "        Curve distance is " << curveDist << G4endl;
+          G4cerr << G4endl
+                 << "The final curve point is not further along"
+                 << " than the original!" << G4endl;
+
+          if( recalculatedEndPoint )
+          {
+            G4cerr << "Recalculation of EndPoint was called with fEpsStep= "
+                   << GetEpsilonStepFor() << G4endl;
+          }
+          G4cerr.precision(20);
+          G4cerr << " Point A (Curve start)   is " << CurveStartPointVelocity
+                 << G4endl;
+          G4cerr << " Point B (Curve   end)   is " << CurveEndPointVelocity
+                 << G4endl;
+          G4cerr << " Point A (Current start) is " << CurrentA_PointVelocity
+                 << G4endl;
+          G4cerr << " Point B (Current end)   is " << CurrentB_PointVelocity
+                 << G4endl;
+          G4cerr << " Point S (Sub start)     is " << SubStart_PointVelocity
+                 << G4endl;
+          G4cerr << " Point E (Trial Point)   is " << CurrentE_Point
+                 << G4endl;
+          G4cerr << " Point F (Intersection)  is " << ApproxIntersecPointV
+                 << G4endl;
+          G4cerr << "        LocateIntersection parameters are : Substep no= "
+                 << substep_no << G4endl;
+          G4cerr << "        Substep depth no= "<< substep_no_p  << " Depth= "
+                 << depth << G4endl;
+
+          G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
+                      "FatalError", FatalException,
+                      "Error in advancing propagation.");
+        }
+        if(restoredFullEndpoint)
+        {
+          fin_section_depth[depth] = restoredFullEndpoint;
+          restoredFullEndpoint = false;
+        }
+      } // EndIf ( E is close enough to the curve, ie point F. )
+        // tests ChordAF_Vector.mag() <= maximum_lateral_displacement 
+
+#ifdef G4DEBUG_LOCATE_INTERSECTION  
+      if( substep_no >= trigger_substepno_print )
+      {
+        G4cout << "Difficulty in converging in "
+               << "G4MultiLevelLocator::EstimateIntersectionPoint():"
+               << G4endl
+               << "    Substep no = " << substep_no << G4endl;
+        if( substep_no == trigger_substepno_print )
+        {
+          printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                       -1.0, NewSafety, 0);
+        }
+        G4cout << " State of point A: "; 
+        printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                     -1.0, NewSafety, substep_no-1, 0);
+        G4cout << " State of point B: "; 
+        printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                     -1.0, NewSafety, substep_no);
+      }
+#endif
+      substep_no++; 
+      substep_no_p++;
+
+    } while (  ( ! found_approximate_intersection )
+            && ( ! there_is_no_intersection )     
+            && ( substep_no_p <= param_substeps) );  // UNTIL found or
+                                                     // failed param substep
+    first_section = false;
+
+    if( (!found_approximate_intersection) && (!there_is_no_intersection) )
+    {
+      G4double did_len = std::abs( CurrentA_PointVelocity.GetCurveLength()
+                       - SubStart_PointVelocity.GetCurveLength()); 
+      G4double all_len = std::abs( CurrentB_PointVelocity.GetCurveLength()
+                       - SubStart_PointVelocity.GetCurveLength());
+   
+      G4double stepLengthAB;
+      G4ThreeVector PointGe;
+      // Check if progress is too slow and if it possible to go deeper,
+      // then halve the step if so
+      //
+      if( ( ( did_len )<fraction_done*all_len)
+         && (depth<max_depth) && (!sub_final_section) )
+      {
+        Second_half=false;
+        depth++;
+
+        G4double Sub_len = (all_len-did_len)/(2.);
+        G4FieldTrack start = CurrentA_PointVelocity;
+        G4MagInt_Driver* integrDriver
+                         = GetChordFinderFor()->GetIntegrationDriver();
+        integrDriver->AccurateAdvance(start, Sub_len, GetEpsilonStepFor());
+        *ptrInterMedFT[depth] = start;
+        CurrentB_PointVelocity = *ptrInterMedFT[depth];
+ 
+        // Adjust 'SubStartPoint' to calculate the 'did_length' in next loop
+        //
+        SubStart_PointVelocity = CurrentA_PointVelocity;
+
+        // Find new trial intersection point needed at start of the loop
+        //
+        G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();
+        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
+     
+        GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
+        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point,
+                                              NewSafety, fPreviousSafety,
+                                              fPreviousSftOrigin,stepLengthAB,
+                                              PointGe);
+        if( Intersects_AB )
+        {
+          last_AF_intersection = Intersects_AB;
+          CurrentE_Point = PointGe;
+          fin_section_depth[depth]=true;
+        }
+        else
+        {
+          // No intersection found for first part of curve
+          // (CurrentA,InterMedPoint[depth]). Go to the second part
+          //
+          Second_half = true;
+        }
+      } // if did_len
+
+      if( (Second_half)&&(depth!=0) )
+      {
+        // Second part of curve (InterMed[depth],Intermed[depth-1])                       ) 
+        // On the depth-1 level normally we are on the 'second_half'
+
+        Second_half = true;
+        //  Find new trial intersection point needed at start of the loop
+        //
+        SubStart_PointVelocity = *ptrInterMedFT[depth];
+        CurrentA_PointVelocity = *ptrInterMedFT[depth];
+        CurrentB_PointVelocity = *ptrInterMedFT[depth-1];
+         // Ensure that the new endpoints are not further apart in space
+        // than on the curve due to different errors in the integration
+        //
+        G4double linDistSq, curveDist; 
+        linDistSq = ( CurrentB_PointVelocity.GetPosition() 
+                    - CurrentA_PointVelocity.GetPosition() ).mag2(); 
+        curveDist = CurrentB_PointVelocity.GetCurveLength()
+                    - CurrentA_PointVelocity.GetCurveLength();
+        if( curveDist*curveDist*(1+2*GetEpsilonStepFor() ) < linDistSq )
+        {
+          // Re-integrate to obtain a new B
+          //
+          G4FieldTrack newEndPointFT=
+                  ReEstimateEndpoint( CurrentA_PointVelocity,
+                                      CurrentB_PointVelocity,
+                                      linDistSq,    // to avoid recalculation
+                                      curveDist );
+          G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
+          CurrentB_PointVelocity = newEndPointFT;
+          if (depth==1)
+          {
+            recalculatedEndPoint = true;
+            IntersectedOrRecalculatedFT = newEndPointFT;
+            // So that we can return it, if it is the endpoint!
+          }
+        }
+
+        G4ThreeVector Point_A    = CurrentA_PointVelocity.GetPosition();
+        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
+        GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
+        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point, NewSafety,
+                                              fPreviousSafety,
+                                              fPreviousSftOrigin,stepLengthAB,
+                                              PointGe);
+        if( Intersects_AB )
+        {
+          last_AF_intersection = Intersects_AB;
+          CurrentE_Point = PointGe;
+        }       
+        depth--;
+        fin_section_depth[depth]=true;
+      }
+    }  // if(!found_aproximate_intersection)
+
+  } while ( ( ! found_approximate_intersection )
+            && ( ! there_is_no_intersection )     
+            && ( substep_no <= max_substeps) ); // UNTIL found or failed
+
+  if( substep_no > max_no_seen )
+  {
+    max_no_seen = substep_no; 
+    if( max_no_seen > warn_substeps )
+    {
+      trigger_substepno_print = max_no_seen-20; // Want to see last 20 steps 
+    } 
+  }
+
+  if(  ( substep_no >= max_substeps)
+      && !there_is_no_intersection
+      && !found_approximate_intersection )
+  {
+    G4cerr << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cerr << "          Abandoning effort to intersect. " << G4endl;
+    G4cerr << "          Information on start & current step follows in cout."
+           << G4endl;
+    G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cout << "          Found intersection = "
+           << found_approximate_intersection << G4endl
+           << "          Intersection exists = "
+           << !there_is_no_intersection << G4endl;
+    G4cout << "          Start and Endpoint of Requested Step:" << G4endl;
+    printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                 -1.0, NewSafety, 0);
+    G4cout << G4endl;
+    G4cout << "          'Bracketing' starting and endpoint of current Sub-Step"
+           << G4endl;
+    printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                 -1.0, NewSafety, substep_no-1);
+    printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                 -1.0, NewSafety, substep_no);
+    G4cout << G4endl;
+ 
+#ifdef FUTURE_CORRECTION
+    // Attempt to correct the results of the method // FIX - TODO
+
+    if ( ! found_approximate_intersection )
+    { 
+      recalculatedEndPoint = true;
+      // Return the further valid intersection point -- potentially A ??
+      // JA/19 Jan 2006
+      IntersectedOrRecalculatedFT = CurrentA_PointVelocity;
+
+      G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
+             << G4endl
+             << "          Did not convergence after " << substep_no
+             << " substeps." << G4endl;
+      G4cout << "          The endpoint was adjused to pointA resulting"
+             << G4endl
+             << "          from the last substep: " << CurrentA_PointVelocity
+             << G4endl;
+    }
+#endif
+
+    G4cout.precision( 10 ); 
+    G4double done_len = CurrentA_PointVelocity.GetCurveLength(); 
+    G4double full_len = CurveEndPointVelocity.GetCurveLength();
+    G4cout << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "        Undertaken only length: " << done_len
+           << " out of " << full_len << " required." << G4endl;
+    G4cout << "        Remaining length = " << full_len - done_len << G4endl; 
+
+    G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
+                "UnableToLocateIntersection", FatalException,
+                "Too many substeps while trying to locate intersection.");
+  }
+  else if( substep_no >= warn_substeps )
+  {  
+    G4int oldprc= G4cout.precision( 10 ); 
+    G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Undertaken length: "  
+           << CurrentB_PointVelocity.GetCurveLength(); 
+    G4cout << " - Needed: "  << substep_no << " substeps." << G4endl
+           << "          Warning level = " << warn_substeps
+           << " and maximum substeps = " << max_substeps << G4endl;
+    G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
+                "DifficultyToLocateIntersection", JustWarning,
+                "Many substeps while trying to locate intersection.");
+    G4cout.precision( oldprc ); 
+  }
+  return  !there_is_no_intersection; //  Success or failure
+}

source/geometry/navigation/src/G4MultiNavigator.cc

@@ -24,7 +24,7 @@
 // ********************************************************************
 //
 //
-// $Id: G4MultiNavigator.cc,v 1.7 2007/11/02 13:48:43 japost Exp $
+// $Id: G4MultiNavigator.cc,v 1.8 2008/10/24 14:00:03 gcosmo Exp $
 // GEANT4 tag $ Name:  $
 // 
 // class G4PathFinder Implementation
@@ -422,7 +422,8 @@ G4MultiNavigator::LocateGlobalPointWithinVolume(const G4ThreeVector& position)
 // ----------------------------------------------------------------------
 
 G4double G4MultiNavigator::ComputeSafety( const G4ThreeVector& position,
-                                                G4double       maxDistance)
+                                          const G4double       maxDistance,
+                                          const G4bool         state)
 {
     // Recompute safety for the relevant point
 
@@ -433,7 +434,7 @@ G4double G4MultiNavigator::ComputeSafety( const G4ThreeVector& position,
 
     for( register int num=0; num< fNoActiveNavigators; ++pNavigatorIter,++num )
     {
-       safety = (*pNavigatorIter)->ComputeSafety( position, maxDistance );
+       safety = (*pNavigatorIter)->ComputeSafety( position, maxDistance, state);
        if( safety < minSafety ) { minSafety = safety; } 
     } 
 

source/geometry/navigation/src/G4Navigator.cc

@@ -24,7 +24,7 @@
 // ********************************************************************
 //
 //
-// $Id: G4Navigator.cc,v 1.37 2007/10/18 14:18:36 gcosmo Exp $
+// $Id: G4Navigator.cc,v 1.38 2008/10/24 14:00:03 gcosmo Exp $
 // GEANT4 tag $ Name:  $
 // 
 // class G4Navigator Implementation
@@ -1213,7 +1213,8 @@ G4ThreeVector G4Navigator::GetLocalExitNormal( G4bool* valid )
 // ********************************************************************
 //
 G4double G4Navigator::ComputeSafety( const G4ThreeVector &pGlobalpoint,
-                                     const G4double pMaxLength)
+                                     const G4double pMaxLength,
+                                     const G4bool keepState)
 {
   G4double newSafety = 0.0;
 
@@ -1235,6 +1236,8 @@ G4double G4Navigator::ComputeSafety( const G4ThreeVector &pGlobalpoint,
   }
 #endif
 
+  if (keepState)  { SetSavedState(); }
+
   G4double distEndpointSq = (pGlobalpoint-fStepEndPoint).mag2(); 
   G4bool   stayedOnEndpoint  = distEndpointSq < kCarTolerance*kCarTolerance; 
   G4bool   endpointOnSurface = fEnteredDaughter || fExitedMother;
@@ -1321,6 +1324,8 @@ G4double G4Navigator::ComputeSafety( const G4ThreeVector &pGlobalpoint,
   fPreviousSftOrigin = pGlobalpoint;
   fPreviousSafety = newSafety; 
 
+  if (keepState)  { RestoreSavedState(); }
+
 #ifdef G4DEBUG_NAVIGATION
   if( fVerbose > 1 )
   {

source/geometry/navigation/src/G4NormalNavigation.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4NormalNavigation.cc,v 1.9 2007/05/11 13:43:59 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // class G4NormalNavigation Implementation

source/geometry/navigation/src/G4ParameterisedNavigation.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4ParameterisedNavigation.cc,v 1.12 2007/11/09 16:06:02 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // class G4ParameterisedNavigation Implementation

source/geometry/navigation/src/G4PathFinder.cc

@@ -24,7 +24,7 @@
 // ********************************************************************
 //
 //
-// $Id: G4PathFinder.cc,v 1.58 2007/11/14 10:04:21 gcosmo Exp $
+// $Id: G4PathFinder.cc,v 1.61 2008/11/13 12:59:26 gcosmo Exp $
 // GEANT4 tag $ Name:  $
 // 
 // class G4PathFinder Implementation
@@ -254,6 +254,7 @@ G4PathFinder::ComputeStep( const G4FieldTrack &InitialFieldTrack,
                   "Number of geometries limiting the step not set."); 
     }
   }
+#ifdef G4DEBUG_PATHFINDER      
   else
   {
      if( proposedStepLength < fTrueMinStep )  // For 2nd+ geometry 
@@ -306,16 +307,16 @@ G4PathFinder::ComputeStep( const G4FieldTrack &InitialFieldTrack,
         // client accessing information for the current track, step 
         // We will simply retrieve the results of the synchronous
         // stepping for this Navigator Id below.
-#ifdef G4DEBUG_PATHFINDER      
+        //
         if( fVerboseLevel > 1 )
         { 
            G4cout << " G4P::CS -> Not calling DoNextLinearStep: " 
                   << " stepNo= " << stepNo << " last= " << fLastStepNo 
                   << " new= " << fNewTrack << " Step already done" << G4endl; 
         }
-#endif
      } 
   }
+#endif
 
   fNewTrack= false; 
 
@@ -579,19 +580,10 @@ void G4PathFinder::ReLocate( const G4ThreeVector& position )
 
   if( (!fNewTrack) && ( longMoveEnd && longMoveSaf ) )
   {  
-     G4ThreeVector  LastSafetyLocation;
-       // Copy to keep last value - and restore
-
-     LastSafetyLocation= fSafetyLocation; 
-
      // Recompute ComputeSafety for end position
      //
      revisedSafety= ComputeSafety(lastEndPosition); 
 
-     // Reset the state of last call to ComputeSafety
-     //
-     ComputeSafety( LastSafetyLocation ); 
-
 #ifdef G4DEBUG_PATHFINDER
 
      const G4double kRadTolerance =
@@ -755,11 +747,11 @@ G4double  G4PathFinder::ComputeSafety( const G4ThreeVector& position )
    G4double minSafety= kInfinity; 
   
    std::vector<G4Navigator*>::iterator pNavigatorIter;
-   pNavigatorIter= fpTransportManager-> GetActiveNavigatorsIterator();
+   pNavigatorIter= fpTransportManager->GetActiveNavigatorsIterator();
 
    for( register G4int num=0; num<fNoActiveNavigators; ++pNavigatorIter,++num )
    {
-      G4double safety = (*pNavigatorIter)->ComputeSafety( position );
+      G4double safety = (*pNavigatorIter)->ComputeSafety( position,true );
       if( safety < minSafety ) { minSafety = safety; } 
       fNewSafetyComputed[num]= safety;
    } 
@@ -1181,7 +1173,7 @@ G4PathFinder::DoNextCurvedStep( const G4FieldTrack &initialState,
      G4double minSafety= kInfinity, safety; 
      for( numNav=0; numNav < fNoActiveNavigators; ++numNav )
      {
-        safety= fpNavigator[numNav]->ComputeSafety( startPoint );
+        safety= fpNavigator[numNav]->ComputeSafety( startPoint, false );
         fPreSafetyValues[numNav]= safety; 
         fCurrentPreStepSafety[numNav]= safety; 
         minSafety = std::min( safety, minSafety ); 

source/geometry/navigation/src/G4PhantomParameterisation.cc

@@ -24,12 +24,12 @@
 // ********************************************************************
 //
 //
-// $Id: G4PhantomParameterisation.cc,v 1.2 2007/12/10 16:29:59 gunter Exp $
+// $Id: G4PhantomParameterisation.cc,v 1.4 2008/01/22 15:02:36 gcosmo Exp $
 // GEANT4 tag $ Name:$
 //
 // class G4PhantomParameterisation implementation
 //
-// Author: Pedro Arce, May 2007
+// May 2007 Pedro Arce,   first version
 //
 // --------------------------------------------------------------------
 
@@ -251,19 +251,19 @@ GetReplicaNo( const G4ThreeVector& localPoint, const G4ThreeVector& localDir )
   // Add +kCarTolerance so that they are first placed on voxel N, and then
   // if the direction is negative substract 1
 
-  G4double fx = (localPoint.x()+fContainerWallX+kCarTolerance)/fVoxelHalfX/2.;
+  G4double fx = (localPoint.x()+fContainerWallX+kCarTolerance)/(fVoxelHalfX*2.);
   G4int nx = G4int(fx);
 
-  G4double fy = (localPoint.y()+fContainerWallY+kCarTolerance)/fVoxelHalfY/2.;
+  G4double fy = (localPoint.y()+fContainerWallY+kCarTolerance)/(fVoxelHalfY*2.);
   G4int ny = G4int(fy);
 
-  G4double fz = (localPoint.z()+fContainerWallZ+kCarTolerance)/fVoxelHalfZ/2.;
+  G4double fz = (localPoint.z()+fContainerWallZ+kCarTolerance)/(fVoxelHalfZ*2.);
   G4int nz = G4int(fz);
 
   // If it is on the surface side, check the direction: if direction is
   // negative place it on the previous voxel (if direction is positive it is
   // already in the next voxel...). 
-  // NOTE: Sometimes this algorithm gives nx = -1, it is always traced to be
+  // Correct also cases where n = -1 or n = fNoVoxel. It is always traced to be
   // due to multiple scattering: track is entering a voxel but multiple
   // scattering changes the angle towards outside
   //
@@ -275,8 +275,12 @@ GetReplicaNo( const G4ThreeVector& localPoint, const G4ThreeVector& localDir )
       {
         nx -= 1;
       }
-      else
+    }
+    else
+    {
+      if( nx == G4int(fNoVoxelX) )  
       {
+        nx -= 1;       
       }
     }
   }
@@ -288,8 +292,12 @@ GetReplicaNo( const G4ThreeVector& localPoint, const G4ThreeVector& localDir )
       {
         ny -= 1;
       }
-      else
+    }
+    else
+    {
+      if( ny == G4int(fNoVoxelY) )  
       {
+        ny -= 1;       
       }
     }
   }
@@ -301,63 +309,69 @@ GetReplicaNo( const G4ThreeVector& localPoint, const G4ThreeVector& localDir )
       {
         nz -= 1;
       }
-      else
+    }
+    else
+    {
+      if( nz == G4int(fNoVoxelZ) )  
       {
+        nz -= 1;       
       }
     }
   }
   
   G4int copyNo = nx + fNoVoxelX*ny + fNoVoxelXY*nz;
 
-  // Correct precision problems
+  // Check if there are still errors 
   //
-  if( copyNo < 0 || copyNo >= G4int(fNoVoxel) )
+  G4bool isOK = true;
+  if( nx < 0 )
   {
-    G4bool isOK = true;
-    if( nx < 0 )
-    {
-      nx = 0;
-      isOK = false;
-    }
-    else if( nx >= G4int(fNoVoxelX) )
-    {
-      nx = fNoVoxelX-1;
-      isOK = false;
-    }
-    if( ny < 0 )
-    {
-      ny = 0;
-      isOK = false;
-    }
-    else if( ny >= G4int(fNoVoxelY) )
-    {
-      ny = fNoVoxelY-1;
-      isOK = false;
-    }
-    if( nz < 0 )
-    {
-      nz = 0;
-      isOK = false;
-    }
-    else if( nz >= G4int(fNoVoxelZ) )
-    {
-      nz = fNoVoxelZ-1;
-      isOK = false;
-    }
-    if( !isOK )
-    {
-      G4cerr << "WARNING - G4PhantomParameterisation::GetReplicaNo()" << G4endl
-             << "          LocalPoint: " << localPoint << G4endl
-             << "          Voxel container size: " << fContainerWallX
-             << " " << fContainerWallY << " " << fContainerWallZ << G4endl;
-      G4Exception("G4PhantomParameterisation::GetReplicaNo()",
-                  "Wrong-copy-number", JustWarning,
-                  "Corrected the copy numbe! It was negative or too big");
-      copyNo = nx + fNoVoxelX*ny + fNoVoxelXY*nz;
-    }
+    nx = 0;
+    isOK = false;
+  }
+  else if( nx >= G4int(fNoVoxelX) )
+  {
+    nx = fNoVoxelX-1;
+    isOK = false;
+  }
+  if( ny < 0 )
+  {
+    ny = 0;
+    isOK = false;
+  }
+  else if( ny >= G4int(fNoVoxelY) )
+  {
+    ny = fNoVoxelY-1;
+    isOK = false;
+  }
+  if( nz < 0 )
+  {
+    nz = 0;
+    isOK = false;
+  }
+  else if( nz >= G4int(fNoVoxelZ) )
+  {
+    nz = fNoVoxelZ-1;
+    isOK = false;
+  }
+  if( !isOK )
+  {
+    G4cerr << "WARNING - G4PhantomParameterisation::GetReplicaNo()" << G4endl
+           << "          LocalPoint: " << localPoint << G4endl
+           << "          LocalDir: " << localDir << G4endl
+           << "          Voxel container size: " << fContainerWallX
+           << " " << fContainerWallY << " " << fContainerWallZ << G4endl
+           << "          LocalPoint - wall: "
+           << localPoint.x()-fContainerWallX << " "
+           << localPoint.y()-fContainerWallY << " "
+           << localPoint.z()-fContainerWallZ << G4endl;
+    G4Exception("G4PhantomParameterisation::GetReplicaNo()",
+                "Wrong-copy-number", JustWarning,
+                "Corrected the copy number! It was negative or too big");
+    copyNo = nx + fNoVoxelX*ny + fNoVoxelXY*nz;
   }
 
-  CheckCopyNo( copyNo ); // not needed, just for debugging code
+  // CheckCopyNo( copyNo ); // not needed, just for debugging code
 
   return copyNo;
 }

source/geometry/navigation/src/G4PropagatorInField.cc

@@ -24,8 +24,6 @@
 // ********************************************************************
 //
 //
-// $Id: G4PropagatorInField.cc,v 1.40 2007/11/16 09:39:14 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
 // 
 // 
 //  This class implements an algorithm to track a particle in a
@@ -49,13 +47,15 @@
 #include "G4GeometryTolerance.hh"
 #include "G4VCurvedTrajectoryFilter.hh"
 #include "G4ChordFinder.hh"
+#include "G4MultiLevelLocator.hh"
 
 ///////////////////////////////////////////////////////////////////////////
 //
 // Constructors and destructor
 
 G4PropagatorInField::G4PropagatorInField( G4Navigator    *theNavigator, 
-                                          G4FieldManager *detectorFieldMgr )
+                                          G4FieldManager *detectorFieldMgr,
+                                          G4VIntersectionLocator *vLocator  )
   : fDetectorFieldMgr(detectorFieldMgr), 
     fCurrentFieldMgr(detectorFieldMgr), 
     fNavigator(theNavigator),
@@ -83,23 +83,23 @@ G4PropagatorInField::G4PropagatorInField( G4Navigator    *theNavigator,
   fPreviousSafety= 0.0;
   kCarTolerance = G4GeometryTolerance::GetInstance()->GetSurfaceTolerance();
 
-  // In case of too slow progress in finding Intersection Point
-  // intermediates Points on the Track must be stored.
-  // Initialise the array of Pointers [max_depth+1] to do this  
-  
-  G4ThreeVector zeroV(0.0,0.0,0.0);
-  for (G4int idepth=0; idepth<max_depth+1; idepth++ )
-  {
-    ptrInterMedFT[ idepth ] = new G4FieldTrack( zeroV, zeroV, 0., 0., 0., 0.);
+  // Definding Intersection Locator and his parameters
+  if(vLocator==0){
+    fIntersectionLocator= new G4MultiLevelLocator(theNavigator);
+    fAllocatedLocator=true;
+  }else{
+    fIntersectionLocator=vLocator;
+    fAllocatedLocator=false;
   }
+  fIntersectionLocator->SetEpsilonStepFor(fEpsilonStep);
+  fIntersectionLocator->SetDeltaIntersectionFor(GetDeltaIntersection());
+  fIntersectionLocator->SetChordFinderFor(GetChordFinder());
+  fIntersectionLocator->SetSafetyParametersFor( fUseSafetyForOptimisation);
 }
 
 G4PropagatorInField::~G4PropagatorInField()
 {
-  for ( G4int idepth=0; idepth<max_depth+1; idepth++)
-  {
-    delete ptrInterMedFT[idepth];
-  }
+  if(fAllocatedLocator)delete  fIntersectionLocator; 
 }
 
 ///////////////////////////////////////////////////////////////////////////
@@ -113,6 +113,7 @@ G4PropagatorInField::ComputeStep(
                 G4double&          currentSafety,                // IN/OUT
                 G4VPhysicalVolume* pPhysVol)
 {
+  
   // If CurrentProposedStepLength is too small for finding Chords
   // then return with no action (for now - TODO: some action)
   //
@@ -148,7 +149,14 @@ G4PropagatorInField::ComputeStep(
   // For the next call, the field manager must again be set
   fSetFieldMgr= false;
 
-  GetChordFinder()->SetChargeMomentumMass(fCharge, fInitialMomentumModulus, fMass);  
+  GetChordFinder()->SetChargeMomentumMass(fCharge, fInitialMomentumModulus, fMass); 
+
+ // Values for Intersection Locator has to be updated on each call
+ // because the CurrentFieldManager changes
+    fIntersectionLocator->SetChordFinderFor(GetChordFinder());
+    fIntersectionLocator->SetSafetyParametersFor( fUseSafetyForOptimisation);
+    fIntersectionLocator->SetEpsilonStepFor(fEpsilonStep);
+    fIntersectionLocator->SetDeltaIntersectionFor(GetDeltaIntersection()); 
 
   G4FieldTrack  CurrentState(pFieldTrack);
   G4FieldTrack  OriginalState = CurrentState;
@@ -286,11 +294,11 @@ G4PropagatorInField::ComputeStep(
        // Find the intersection point of AB true path with the surface
        //   of vol(A), if it exists. Start with point E as first "estimate".
        G4bool recalculatedEndPt= false;
-       G4bool found_intersection = 
-         LocateIntersectionPoint( SubStepStartState, CurrentState, 
+       
+         G4bool found_intersection = fIntersectionLocator->
+         EstimateIntersectionPoint( SubStepStartState, CurrentState, 
                                   InterSectionPointE, IntersectPointVelct_G,
-                                  recalculatedEndPt);
-       //G4cout<<"In Locate"<<recalculatedEndPt<<"  and V"<<IntersectPointVelct_G.GetPosition()<<G4endl;
+                                  recalculatedEndPt,fPreviousSafety,fPreviousSftOrigin);
        intersects = intersects && found_intersection;
        if( found_intersection ) {        
           End_PointAndTangent= IntersectPointVelct_G;  // G is our EndPoint ...
@@ -404,576 +412,22 @@ G4PropagatorInField::ComputeStep(
      G4cout << " WARNING - G4PropagatorInField::ComputeStep():" << G4endl
             << " Zero progress for "  << fNoZeroStep << " attempted steps." 
             << G4endl;
+     G4cout << "Proposed Step is "<<CurrentProposedStepLength <<" but Step Taken is "<< fFull_CurveLen_of_LastAttempt <<G4endl;
+     G4cout << "For Particle with Charge ="<<fCharge
+            << " Momentum="<< fInitialMomentumModulus<<" Mass="<< fMass<<G4endl;
+       if( pPhysVol )
+          G4cout << " in the volume " << pPhysVol->GetName() ; 
+       else
+         G4cout << " in unknown or null volume. " ; 
+       G4cout << G4endl;
      if ( fVerboseLevel > 2 )
        G4cout << " Particle that is stuck will be killed." << G4endl;
      fNoZeroStep = 0; 
   }
-  //  G4cout << "G4PropagatorInField returns " << TruePathLength << G4endl;
+ 
   return TruePathLength;
 }
 
-// --------------------------------------------------------------------------
-// G4bool 
-// G4PropagatorInField::LocateIntersectionPoint( 
-//   const G4FieldTrack&       CurveStartPointVelocity,   //  A
-//   const G4FieldTrack&       CurveEndPointVelocity,     //  B
-//   const G4ThreeVector&      TrialPoint,                //  E
-//         G4FieldTrack&       IntersectedOrRecalculated  // Output
-//         G4bool&             recalculated)              // Out
-// --------------------------------------------------------------------------
-//
-// Function that returns the intersection of the true path with the surface
-// of the current volume (either the external one or the inner one with one
-// of the daughters 
-//
-//     A = Initial point
-//     B = another point 
-//
-// Both A and B are assumed to be on the true path.
-//
-//     E is the first point of intersection of the chord AB with 
-//     a volume other than A  (on the surface of A or of a daughter)
-//
-// Convention of Use :
-//     i) If it returns "true", then IntersectionPointVelocity is set
-//       to the approximate intersection point.
-//    ii) If it returns "false", no intersection was found.
-//          The validity of IntersectedOrRecalculated depends on 'recalculated'
-//        a) if latter is false, then IntersectedOrRecalculated is invalid. 
-//        b) if latter is true,  then IntersectedOrRecalculated is
-//             the new endpoint, due to a re-integration.
-// --------------------------------------------------------------------------
-
-G4bool 
-G4PropagatorInField::LocateIntersectionPoint( 
-  const   G4FieldTrack&       CurveStartPointVelocity,   //  A
-  const   G4FieldTrack&       CurveEndPointVelocity,     //  B
-  const   G4ThreeVector&      TrialPoint,                //  E
-          G4FieldTrack&       IntersectedOrRecalculatedFT, // Out: point found
-          G4bool&             recalculatedEndPoint)        // Out: 
-{
-  // Find Intersection Point ( A, B, E )  of true path AB - start at E.
-
-  G4bool found_approximate_intersection = false;
-  G4bool there_is_no_intersection       = false;
-  
-  G4FieldTrack  CurrentA_PointVelocity = CurveStartPointVelocity; 
-  G4FieldTrack  CurrentB_PointVelocity = CurveEndPointVelocity;
-  G4ThreeVector CurrentE_Point = TrialPoint;
-  G4FieldTrack ApproxIntersecPointV(CurveEndPointVelocity); // FT-Def-Construct
-  G4double    NewSafety= -0.0;
-
-  G4bool final_section= true;  // Shows whether current section is last
-                               // (i.e. B=full end)
-  G4bool first_section=true;
-  recalculatedEndPoint= false; 
-
-  G4bool restoredFullEndpoint= false;
-
-  G4int substep_no = 0;
-   
-  // Limits for substep number
-  //
-  const G4int max_substeps=   10000;  // Test 120  (old value 100 )
-  const G4int warn_substeps=   1000;  //      100  
-
-  // Statistics for substeps
-  //
-  static G4int max_no_seen= -1; 
-  static G4int trigger_substepno_print= warn_substeps - 20 ;
-
-  //--------------------------------------------------------------------------  
-  //  Algoritm for the case if progress in founding intersection is too slow.
-  //  Process is defined too slow if after N=param_substeps advances on the
-  //  path, it will be only 'fraction_done' of the total length.
-  //  In this case the remaining length is divided in two half and 
-  //  the loop is restarted for each half.  
-  //  If progress is still too slow, the division in two halfs continue
-  //  until 'max_depth'.
-  //--------------------------------------------------------------------------
-
-  const G4int param_substeps=10; // Test value for the maximum number
-                                 // of substeps
-  const G4double fraction_done=0.3;
-
-  G4bool Second_half=false;      // First half or second half of divided step
-
-  // We need to know this for the 'final_section':
-  // real 'final_section' or first half 'final_section'
-  // In algorithm it is considered that the 'Second_half' is true
-  // and it becomes false only if we are in the first-half of level
-  // depthness or if we are in the first section
-
-  G4int depth=0; // Depth counts how many subdivisions of initial step made
-
-#ifdef G4DEBUG_FIELD
-  static G4double tolerance= 1.0e-8; 
-  G4ThreeVector  StartPosition= CurveStartPointVelocity.GetPosition(); 
-  if( (TrialPoint - StartPosition).mag() < tolerance * mm ) 
-  {
-     G4cerr << "WARNING - G4PropagatorInField::LocateIntersectionPoint()"
-            << G4endl
-            << "          Intermediate F point is on top of starting point A."
-            << G4endl;
-     G4Exception("G4PropagatorInField::LocateIntersectionPoint()", 
-                 "IntersectionPointIsAtStart", JustWarning,
-                 "Intersection point F is exactly at start point A." ); 
-  }
-#endif
-
-  // Intermediates Points on the Track = Subdivided Points must be stored.
-  // Give the initial values to 'InterMedFt'
-  // Important is 'ptrInterMedFT[0]', it saves the 'EndCurvePoint'
-  //
-  *ptrInterMedFT[0] = CurveEndPointVelocity;
-  for (G4int idepth=1; idepth<max_depth+1; idepth++ )
-  {
-    *ptrInterMedFT[idepth]=CurveStartPointVelocity;
-  }
-
-  // 'SubStartPoint' is needed to calculate the length of the divided step
-  //
-  G4FieldTrack SubStart_PointVelocity = CurveStartPointVelocity;
-   
-  do
-  {
-    G4int substep_no_p = 0;
-    G4bool sub_final_section = false; // the same as final_section,
-                                      // but for 'sub_section'
-    do // REPEAT param
-    {
-      G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();  
-      G4ThreeVector Point_B = CurrentB_PointVelocity.GetPosition();
-       
-      // F = a point on true AB path close to point E 
-      // (the closest if possible)
-      //
-      ApproxIntersecPointV = GetChordFinder()
-                             ->ApproxCurvePointV( CurrentA_PointVelocity, 
-                                                  CurrentB_PointVelocity, 
-                                                  CurrentE_Point,
-                                                  fEpsilonStep );
-      //  The above method is the key & most intuitive part ...
-
-#ifdef G4DEBUG_FIELD
-      if( ApproxIntersecPointV.GetCurveLength() > 
-          CurrentB_PointVelocity.GetCurveLength() * (1.0 + tolerance) )
-      {
-        G4cerr << "ERROR - G4PropagatorInField::LocateIntersectionPoint()"
-               << G4endl
-               << "        Intermediate F point is more advanced than"
-               << " endpoint B." << G4endl;
-        G4Exception("G4PropagatorInField::LocateIntersectionPoint()", 
-                    "IntermediatePointConfusion", FatalException,
-                    "Intermediate F point is past end B point" ); 
-      }
-#endif
-
-      G4ThreeVector CurrentF_Point= ApproxIntersecPointV.GetPosition();
-
-      // First check whether EF is small - then F is a good approx. point 
-      // Calculate the length and direction of the chord AF
-      //
-      G4ThreeVector  ChordEF_Vector = CurrentF_Point - CurrentE_Point;
-
-      if ( ChordEF_Vector.mag2() <= sqr(GetDeltaIntersection()) )
-      {
-        found_approximate_intersection = true;
-
-        // Create the "point" return value
-        //
-        IntersectedOrRecalculatedFT = ApproxIntersecPointV;
-        IntersectedOrRecalculatedFT.SetPosition( CurrentE_Point );
-       
-        // Note: in order to return a point on the boundary, 
-        //       we must return E. But it is F on the curve.
-        //       So we must "cheat": we are using the position at point E
-        //       and the velocity at point F !!!
-        //
-        // This must limit the length we can allow for displacement!
-      }
-      else  // E is NOT close enough to the curve (ie point F)
-      {
-        // Check whether any volumes are encountered by the chord AF
-        // ---------------------------------------------------------
-        // First relocate to restore any Voxel etc information
-        // in the Navigator before calling ComputeStep()
-        //
-        fNavigator->LocateGlobalPointWithinVolume( Point_A );
-
-        G4ThreeVector PointG;   // Candidate intersection point
-        G4double stepLengthAF; 
-        G4bool Intersects_AF = IntersectChord( Point_A,   CurrentF_Point,
-                                               NewSafety, stepLengthAF,
-                                               PointG );
-        if( Intersects_AF )
-        {
-          // G is our new Candidate for the intersection point.
-          // It replaces  "E" and we will repeat the test to see if
-          // it is a good enough approximate point for us.
-          //       B    <- F
-          //       E    <- G
-
-          CurrentB_PointVelocity = ApproxIntersecPointV;
-          CurrentE_Point = PointG;  
-
-          // By moving point B, must take care if current
-          // AF has no intersection to try current FB!!
-          //
-          final_section= false; 
-
-#ifdef G4VERBOSE
-          if( fVerboseLevel > 3 )
-          {
-            G4cout << "G4PiF::LI> Investigating intermediate point"
-                   << " at s=" << ApproxIntersecPointV.GetCurveLength()
-                   << " on way to full s="
-                   << CurveEndPointVelocity.GetCurveLength() << G4endl;
-          }
-#endif
-        }
-        else  // not Intersects_AF
-        {  
-          // In this case:
-          // There is NO intersection of AF with a volume boundary.
-          // We must continue the search in the segment FB!
-          //
-          fNavigator->LocateGlobalPointWithinVolume( CurrentF_Point );
-
-          G4double stepLengthFB;
-          G4ThreeVector PointH;
-
-          // Check whether any volumes are encountered by the chord FB
-          // ---------------------------------------------------------
-
-          G4bool Intersects_FB = IntersectChord( CurrentF_Point, Point_B, 
-                                                 NewSafety, stepLengthFB,
-                                                 PointH );
-          if( Intersects_FB )
-          { 
-            // There is an intersection of FB with a volume boundary
-            // H <- First Intersection of Chord FB 
-
-            // H is our new Candidate for the intersection point.
-            // It replaces  "E" and we will repeat the test to see if
-            // it is a good enough approximate point for us.
-
-            // Note that F must be in volume volA  (the same as A)
-            // (otherwise AF would meet a volume boundary!)
-            //   A    <- F 
-            //   E    <- H
-
-            CurrentA_PointVelocity = ApproxIntersecPointV;
-            CurrentE_Point = PointH;
-          }
-          else  // not Intersects_FB
-          {
-            // There is NO intersection of FB with a volume boundary
-
-            if( final_section  )
-            {
-              // If B is the original endpoint, this means that whatever
-              // volume(s) intersected the original chord, none touch the
-              // smaller chords we have used.
-              // The value of 'IntersectedOrRecalculatedFT' returned is
-              // likely not valid 
-
-              // Check on real final_section or SubEndSection
-              //
-              if( ((Second_half)&&(depth==0)) || (first_section) )
-              {
-                there_is_no_intersection = true;   // real final_section
-              }
-              else
-              {
-                // end of subsection, not real final section 
-                // exit from the and go to the depth-1 level 
-
-                substep_no_p = param_substeps+2;  // exit from the loop
-
-                // but 'Second_half' is still true because we need to find
-                // the 'CurrentE_point' for the next loop
-                //
-                Second_half = true; 
-                sub_final_section = true;
-           
-              }
-            }
-            else
-            {
-              // We must restore the original endpoint
-
-              CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
-              CurrentB_PointVelocity = CurveEndPointVelocity;
-              restoredFullEndpoint = true;
-            }
-          } // Endif (Intersects_FB)
-        } // Endif (Intersects_AF)
-
-        // Ensure that the new endpoints are not further apart in space
-        // than on the curve due to different errors in the integration
-        //
-        G4double linDistSq, curveDist; 
-        linDistSq = ( CurrentB_PointVelocity.GetPosition() 
-                    - CurrentA_PointVelocity.GetPosition() ).mag2(); 
-        curveDist = CurrentB_PointVelocity.GetCurveLength()
-                    - CurrentA_PointVelocity.GetCurveLength();
-        if( curveDist*(curveDist+2*perMillion ) < linDistSq )
-        {
-          // Re-integrate to obtain a new B
-          //
-          G4FieldTrack newEndPointFT=
-                  ReEstimateEndpoint( CurrentA_PointVelocity,
-                                      CurrentB_PointVelocity,
-                                      linDistSq,    // to avoid recalculation
-                                      curveDist );
-          G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
-          CurrentB_PointVelocity = newEndPointFT;
-
-          if( (final_section)&&(Second_half)&&(depth==0) ) // real final section
-          {
-            recalculatedEndPoint = true;
-            IntersectedOrRecalculatedFT = newEndPointFT;
-              // So that we can return it, if it is the endpoint!
-          }
-        }
-        if( curveDist < 0.0 )
-        {
-          G4cerr << "ERROR - G4PropagatorInField::LocateIntersectionPoint()"
-                 << G4endl
-                 << "        Error in advancing propagation." << G4endl;
-          fVerboseLevel = 5; // Print out a maximum of information
-          printStatus( CurrentA_PointVelocity,  CurrentB_PointVelocity,
-                       -1.0, NewSafety,  substep_no, 0 );
-          G4cerr << "        Point A (start) is " << CurrentA_PointVelocity
-                 << G4endl;
-          G4cerr << "        Point B (end)   is " << CurrentB_PointVelocity
-                 << G4endl;
-          G4cerr << "        Curve distance is " << curveDist << G4endl;
-          G4cerr << G4endl
-                 << "The final curve point is not further along"
-                 << " than the original!" << G4endl;
-          G4Exception("G4PropagatorInField::LocateIntersectionPoint()",
-                      "FatalError", FatalException,
-                      "Error in advancing propagation.");
-        }
-
-        if(restoredFullEndpoint)
-        {
-          final_section = restoredFullEndpoint;
-          restoredFullEndpoint = false;
-        }
-      } // EndIf ( E is close enough to the curve, ie point F. )
-        // tests ChordAF_Vector.mag() <= maximum_lateral_displacement 
-
-#ifdef G4DEBUG_LOCATE_INTERSECTION  
-      if( substep_no >= trigger_substepno_print )
-      {
-        G4cout << "Difficulty in converging in "
-               << "G4PropagatorInField::LocateIntersectionPoint():"
-               << G4endl
-               << "    Substep no = " << substep_no << G4endl;
-        if( substep_no == trigger_substepno_print )
-        {
-          printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
-                       -1.0, NewSafety, 0, 0);
-        }
-        G4cout << " State of point A: "; 
-        printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
-                     -1.0, NewSafety, substep_no-1, 0);
-        G4cout << " State of point B: "; 
-        printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
-                     -1.0, NewSafety, substep_no, 0);
-      }
-#endif
-
-      substep_no++; 
-      substep_no_p++;
-
-    } while (  ( ! found_approximate_intersection )
-            && ( ! there_is_no_intersection )     
-            && ( substep_no_p <= param_substeps) );  // UNTIL found or
-                                                     // failed param substep
-    first_section = false;
-
-    if( (!found_approximate_intersection) && (!there_is_no_intersection) )
-    {
-      G4double did_len = std::abs( CurrentA_PointVelocity.GetCurveLength()
-                       - SubStart_PointVelocity.GetCurveLength()); 
-      G4double all_len = std::abs( CurrentB_PointVelocity.GetCurveLength()
-                       - SubStart_PointVelocity.GetCurveLength());
-   
-      G4double stepLengthAB;
-      G4ThreeVector PointGe;
-
-      // Check if progress is too slow and if it possible to go deeper,
-      // then halve the step if so
-      //
-      if( ( ( did_len )<fraction_done*all_len)
-         && (depth<max_depth) && (!sub_final_section) )
-      {
-
-        Second_half=false;
-        depth++;
-
-        G4double Sub_len = (all_len-did_len)/(2.);
-        G4FieldTrack start = CurrentA_PointVelocity;
-        G4MagInt_Driver* integrDriver=GetChordFinder()->GetIntegrationDriver();
-        integrDriver->AccurateAdvance(start, Sub_len, fEpsilonStep);
-        *ptrInterMedFT[depth] = start;
-        CurrentB_PointVelocity = *ptrInterMedFT[depth];
- 
-        // Adjust 'SubStartPoint' to calculate the 'did_length' in next loop
-        //
-        SubStart_PointVelocity = CurrentA_PointVelocity;
-
-        // Find new trial intersection point needed at start of the loop
-        //
-        G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();
-        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
-     
-        fNavigator->LocateGlobalPointWithinVolume(Point_A);
-        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point,
-                                              NewSafety, stepLengthAB, PointGe);
-        if(Intersects_AB)
-        {
-          CurrentE_Point = PointGe;
-        }
-        else
-        {
-          // No intersection found for first part of curve
-          // (CurrentA,InterMedPoint[depth]). Go to the second part
-          //
-          Second_half = true;
-        }
-      } // if did_len
-
-      if( (Second_half)&&(depth!=0) )
-      {
-        // Second part of curve (InterMed[depth],Intermed[depth-1])                       ) 
-        // On the depth-1 level normally we are on the 'second_half'
-
-        Second_half = true;
-
-        //  Find new trial intersection point needed at start of the loop
-        //
-        SubStart_PointVelocity = *ptrInterMedFT[depth];
-        CurrentA_PointVelocity = *ptrInterMedFT[depth];
-        CurrentB_PointVelocity = *ptrInterMedFT[depth-1];
-        G4ThreeVector Point_A    = CurrentA_PointVelocity.GetPosition();
-        G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
-        fNavigator->LocateGlobalPointWithinVolume(Point_A);
-        G4bool Intersects_AB = IntersectChord(Point_A, SubE_point, NewSafety,
-                                              stepLengthAB, PointGe);
-        if(Intersects_AB)
-        {
-          CurrentE_Point = PointGe;
-        }
-        else
-        {
-          final_section = true;
-        }
-        depth--;
-      }
-    }  // if(!found_aproximate_intersection)
-
-  } while ( ( ! found_approximate_intersection )
-            && ( ! there_is_no_intersection )     
-            && ( substep_no <= max_substeps) ); // UNTIL found or failed
-
-  if( substep_no > max_no_seen )
-  {
-    max_no_seen = substep_no; 
-    if( max_no_seen > warn_substeps )
-    {
-      trigger_substepno_print = max_no_seen-20; // Want to see last 20 steps 
-    } 
-  }
-
-  if(  ( substep_no >= max_substeps)
-      && !there_is_no_intersection
-      && !found_approximate_intersection )
-  {
-    G4cerr << "WARNING - G4PropagatorInField::LocateIntersectionPoint()"
-           << G4endl
-           << "          Convergence is requiring too many substeps: "
-           << substep_no << G4endl;
-    G4cerr << "          Abandoning effort to intersect. " << G4endl;
-    G4cerr << "          Information on start & current step follows in cout."
-           << G4endl;
-    G4cout << "WARNING - G4PropagatorInField::LocateIntersectionPoint()"
-           << G4endl
-           << "          Convergence is requiring too many substeps: "
-           << substep_no << G4endl;
-    G4cout << "          Found intersection = "
-           << found_approximate_intersection << G4endl
-           << "          Intersection exists = "
-           << !there_is_no_intersection << G4endl;
-    G4cout << "          Start and Endpoint of Requested Step:" << G4endl;
-    printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
-                 -1.0, NewSafety, 0, 0);
-    G4cout << G4endl;
-    G4cout << "          'Bracketing' starting and endpoint of current Sub-Step"
-           << G4endl;
-    printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
-                 -1.0, NewSafety, substep_no-1, 0);
-    printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
-                 -1.0, NewSafety, substep_no, 0);
-    G4cout << G4endl;
- 
-#ifdef FUTURE_CORRECTION
-    // Attempt to correct the results of the method // FIX - TODO
-
-    if ( ! found_approximate_intersection )
-    { 
-      recalculatedEndPoint = true;
-      // Return the further valid intersection point -- potentially A ??
-      // JA/19 Jan 2006
-      IntersectedOrRecalculatedFT = CurrentA_PointVelocity;
-
-      G4cout << "WARNING - G4PropagatorInField::LocateIntersectionPoint()"
-             << G4endl
-             << "          Did not convergence after " << substep_no
-             << " substeps." << G4endl;
-      G4cout << "          The endpoint was adjused to pointA resulting"
-             << G4endl
-             << "          from the last substep: " << CurrentA_PointVelocity
-             << G4endl;
-    }
-#endif
-
-    G4cout.precision( 10 ); 
-    G4double done_len = CurrentA_PointVelocity.GetCurveLength(); 
-    G4double full_len = CurveEndPointVelocity.GetCurveLength();
-    G4cout << "ERROR - G4PropagatorInField::LocateIntersectionPoint()"
-           << G4endl
-           << "        Undertaken only length: " << done_len
-           << " out of " << full_len << " required." << G4endl;
-    G4cout << "        Remaining length = " << full_len - done_len << G4endl; 
-
-    G4Exception("G4PropagatorInField::LocateIntersectionPoint()",
-                "UnableToLocateIntersection", FatalException,
-                "Too many substeps while trying to locate intersection.");
-  }
-  else if( substep_no >= warn_substeps )
-  {  
-    int oldprc= G4cout.precision( 10 ); 
-    G4cout << "WARNING - G4PropagatorInField::LocateIntersectionPoint()"
-           << G4endl
-           << "          Undertaken length: "  
-           << CurrentB_PointVelocity.GetCurveLength(); 
-    G4cout << " - Needed: "  << substep_no << " substeps." << G4endl
-           << "          Warning level = " << warn_substeps
-           << " and maximum substeps = " << max_substeps << G4endl;
-    G4Exception("G4PropagatorInField::LocateIntersectionPoint()",
-                "DifficultyToLocateIntersection", JustWarning,
-                "Many substeps while trying to locate intersection.");
-    G4cout.precision( oldprc ); 
-  }
- 
-  return  !there_is_no_intersection; //  Success or failure
-}
-
 ///////////////////////////////////////////////////////////////////////////
 //
 // Dumps status of propagator.
@@ -1106,216 +560,6 @@ G4PropagatorInField::PrintStepLengthDiagnostic(
          << G4endl;
 }
 
-G4bool
-G4PropagatorInField::IntersectChord( G4ThreeVector  StartPointA, 
-                                     G4ThreeVector  EndPointB,
-                                     G4double      &NewSafety,
-                                     G4double      &LinearStepLength,
-                                     G4ThreeVector &IntersectionPoint
-                                   )
-{
-    // Calculate the direction and length of the chord AB
-    G4ThreeVector  ChordAB_Vector = EndPointB - StartPointA;
-    G4double       ChordAB_Length = ChordAB_Vector.mag();  // Magnitude (norm)
-    G4ThreeVector  ChordAB_Dir =    ChordAB_Vector.unit();
-    G4bool intersects;
-
-    G4ThreeVector OriginShift = StartPointA - fPreviousSftOrigin ;
-    G4double      MagSqShift  = OriginShift.mag2() ;
-    G4double      currentSafety;
-    G4bool        doCallNav= false;
-
-    if( MagSqShift >= sqr(fPreviousSafety) )
-    {
-        currentSafety = 0.0 ;
-    }else{
-        currentSafety = fPreviousSafety - std::sqrt(MagSqShift) ;
-    }
-
-    if( fUseSafetyForOptimisation && (ChordAB_Length <= currentSafety) )
-    {
-       // The Step is guaranteed to be taken
-
-       LinearStepLength = ChordAB_Length;
-       intersects = false;
-
-       NewSafety= currentSafety;
-
-#if 0 
-       G4cout << " G4PropagatorInField does not call Navigator::ComputeStep " << G4endl ;
-       G4cout << "    step= " << LinearStepLength << " safety= " << NewSafety << G4endl;
-       G4cout << "    safety: Origin = " << fPreviousSftOrigin << " val= " << fPreviousSafety << G4endl;
-#endif 
-    }
-    else
-    {
-       doCallNav= true; 
-       // Check whether any volumes are encountered by the chord AB
-
-       // G4cout << " G4PropagatorInField calling Navigator::ComputeStep " << G4endl ;
-
-       LinearStepLength = 
-        fNavigator->ComputeStep( StartPointA, ChordAB_Dir,
-                                 ChordAB_Length, NewSafety );
-       intersects = (LinearStepLength <= ChordAB_Length); 
-       // G4Navigator contracts to return k_infinity if len==asked
-       // and it did not find a surface boundary at that length
-       LinearStepLength = std::min( LinearStepLength, ChordAB_Length);
-
-       // G4cout << " G4PiF got step= " << LinearStepLength << " safety= " << NewSafety << G4endl;
-
-       // Save the last calculated safety!
-       fPreviousSftOrigin = StartPointA;
-       fPreviousSafety= NewSafety;
-
-       if( intersects ){
-          // Intersection Point of chord AB and either volume A's surface 
-          //                                or a daughter volume's surface ..
-          IntersectionPoint = StartPointA + LinearStepLength * ChordAB_Dir;
-       }
-    }
-
-#ifdef DEBUG_INTERSECTS_CHORD
-    // printIntersection( 
-    // StartPointA, EndPointB, LinearStepLength, IntersectionPoint, NewSafety
-
-    G4cout << " G4PropagatorInField::IntersectChord reports " << G4endl;
-    G4cout << " PiF-IC> "
-           << "Start="  << std::setw(12) << StartPointA       << " "
-           << "End= "   << std::setw(8) << EndPointB         << " "
-           << "StepIn=" << std::setw(8) << LinearStepLength  << " "
-           << "NewSft=" << std::setw(8) << NewSafety << " " 
-           << "CallNav=" << doCallNav      << "  "
-           << "Intersects " << intersects     << "  "; 
-    if( intersects ) 
-      G4cout << "IntrPt=" << std::setw(8) << IntersectionPoint << " " ; 
-    G4cout << G4endl;
-#endif
-
-    return intersects;
-}
-
-// --------------------- oooo000000000000oooo ----------------------------
-
-G4FieldTrack G4PropagatorInField::
-ReEstimateEndpoint( const G4FieldTrack &CurrentStateA,  
-                    const G4FieldTrack &EstimatedEndStateB,
-                          G4double      linearDistSq,
-                          G4double      curveDist
-                  )
-{
-  // G4double checkCurveDist= EstimatedEndStateB.GetCurveLength()
-  //   - CurrentStateA.GetCurveLength();
-  // G4double checkLinDistSq= (EstimatedEndStateB.GetPosition()
-  //                    - CurrentStateA.GetPosition() ).mag2();
-
-  G4FieldTrack newEndPoint( CurrentStateA );
-  G4MagInt_Driver* integrDriver= GetChordFinder()->GetIntegrationDriver(); 
-
-  G4FieldTrack retEndPoint( CurrentStateA );
-  G4bool goodAdvance;
-  G4int  itrial=0;
-  const G4int no_trials= 20;
-
-  G4double endCurveLen= EstimatedEndStateB.GetCurveLength();
-  do
-  {
-     G4double currentCurveLen= newEndPoint.GetCurveLength();
-     G4double advanceLength= endCurveLen - currentCurveLen ; 
-     if (std::abs(advanceLength)<kCarTolerance)
-     {
-       advanceLength=(EstimatedEndStateB.GetPosition()
-                     -newEndPoint.GetPosition()).mag();
-     }
-     goodAdvance= 
-       integrDriver->AccurateAdvance(newEndPoint, advanceLength, fEpsilonStep);
-     //              ***************
-  }
-  while( !goodAdvance && (++itrial < no_trials) );
-
-  if( goodAdvance )
-  {
-    retEndPoint= newEndPoint; 
-  }
-  else
-  {
-    retEndPoint= EstimatedEndStateB; // Could not improve without major work !!
-  }
-
-  //  All the work is done
-  //   below are some diagnostics only -- before the return!
-  // 
-  static const G4String MethodName("G4PropagatorInField::ReEstimateEndpoint");
-
-#ifdef G4VERBOSE
-  G4int  latest_good_trials=0;
-  if( itrial > 1)
-  {
-    if( fVerboseLevel > 0 )
-    {
-      G4cout << MethodName << " called - goodAdv= " << goodAdvance
-             << " trials = " << itrial
-             << " previous good= " << latest_good_trials
-             << G4endl;
-    }
-    latest_good_trials=0; 
-  }
-  else
-  {   
-    latest_good_trials++; 
-  }
-#endif
-
-#ifdef G4DEBUG_FIELD
-  G4double lengthDone = newEndPoint.GetCurveLength() 
-                      - CurrentStateA.GetCurveLength(); 
-  if( !goodAdvance )
-  {
-    if( fVerboseLevel >= 3 )
-    {
-      G4cout << MethodName << "> AccurateAdvance failed " ;
-      G4cout << " in " << itrial << " integration trials/steps. " << G4endl;
-      G4cout << " It went only " << lengthDone << " instead of " << curveDist
-             << " -- a difference of " << curveDist - lengthDone  << G4endl;
-      G4cout << " ReEstimateEndpoint> Reset endPoint to original value!"
-             << G4endl;
-    }
-  }
-
-  static G4int noInaccuracyWarnings = 0; 
-  G4int maxNoWarnings = 10;
-  if (  (noInaccuracyWarnings < maxNoWarnings ) 
-       || (fVerboseLevel > 1) )
-    {
-      G4cerr << "G4PropagatorInField::LocateIntersectionPoint():"
-             << G4endl
-             << " Warning: Integration inaccuracy requires" 
-             <<   " an adjustment in the step's endpoint."  << G4endl
-             << "   Two mid-points are further apart than their"
-             <<   " curve length difference"                << G4endl 
-             << "   Dist = "       << std::sqrt(linearDistSq)
-             << " curve length = " << curveDist             << G4endl; 
-      G4cerr << " Correction applied is " 
-             << (newEndPoint.GetPosition()-EstimatedEndStateB.GetPosition()).mag()
-             << G4endl;
-    }
-#else
-  // Statistics on the RMS value of the corrections
-
-  static G4int    noCorrections=0;
-  static G4double sumCorrectionsSq = 0;
-  noCorrections++; 
-  if( goodAdvance )
-  {
-    sumCorrectionsSq += (EstimatedEndStateB.GetPosition() - 
-                         newEndPoint.GetPosition()).mag2();
-  }
-  linearDistSq -= curveDist; // To use linearDistSq ... !
-#endif
-
-  return retEndPoint;
-}
-
 // Access the points which have passed through the filter. The
 // points are stored as ThreeVectors for the initial impelmentation
 // only (jacek 30/10/2002)

source/geometry/navigation/src/G4ReplicaNavigation.cc

@@ -24,8 +24,8 @@
 // ********************************************************************
 //
 //
-// $Id: G4ReplicaNavigation.cc,v 1.17 2007/11/16 09:39:14 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// $Id: G4ReplicaNavigation.cc,v 1.19 2008/04/28 15:39:55 gcosmo Exp $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // class G4ReplicaNavigation Implementation
@@ -1043,7 +1043,7 @@ G4ReplicaNavigation::BackLocate(G4NavigationHistory &history,
   motherSolid = pNRMother->GetLogicalVolume()->GetSolid();
   goodPoint = history.GetTransform(mdepth).TransformPoint(globalPoint);
   insideCode = motherSolid->Inside(goodPoint);
-  if ( (insideCode==kOutside)||(insideCode==kSurface)&&exiting )
+  if ( (insideCode==kOutside)||((insideCode==kSurface)&&exiting) )
   {
     // Outside mother -> back up to mother level
     // Locate.. in Navigator will back up one more level
@@ -1065,7 +1065,7 @@ G4ReplicaNavigation::BackLocate(G4NavigationHistory &history,
       insideCode = Inside(history.GetVolume(depth),
                           history.GetReplicaNo(depth),
                           repPoint);
-      if ( (insideCode==kOutside)||(insideCode==kSurface)&&exiting )
+      if ( (insideCode==kOutside)||((insideCode==kSurface)&&exiting) )
       {
         localPoint = goodPoint;
         history.BackLevel(cdepth-depth);
@@ -1084,7 +1084,7 @@ G4ReplicaNavigation::BackLocate(G4NavigationHistory &history,
     // of *previous* level - location code in navigator will back up one
     // level [And also manage blocking]
     //
-    if ( (insideCode==kOutside)||(insideCode==kSurface)&&exiting )
+    if ( (insideCode==kOutside)||((insideCode==kSurface)&&exiting) )
     {
       localPoint = goodPoint;
     }

source/geometry/navigation/src/G4SafetyHelper.cc

@@ -23,7 +23,7 @@
 // * acceptance of all terms of the Geant4 Software license.          *
 // ********************************************************************
 //
-// $Id: G4SafetyHelper.cc,v 1.15 2007/11/14 10:04:21 gcosmo Exp $
+// $Id: G4SafetyHelper.cc,v 1.16 2008/10/24 14:00:03 gcosmo Exp $
 // GEANT4 tag $ Name:  $
 // 
 // class G4SafetyHelper Implementation
@@ -127,12 +127,12 @@ G4double G4SafetyHelper::ComputeSafety( const G4ThreeVector& position )
     if( !fUseParallelGeometries )
     {
       // Safety for mass geometry
-      fLastSafety = fpMassNavigator->ComputeSafety(position); 
+      fLastSafety = fpMassNavigator->ComputeSafety(position,true); 
     }
     else
     {
       // Safety for all geometries
-      fLastSafety = fpPathFinder->ComputeSafety( position ); 
+      fLastSafety = fpPathFinder->ComputeSafety(position); 
     } 
     newSafety = fLastSafety;
   }

source/geometry/navigation/src/G4SimpleLocator.cc

@@ -0,0 +1,483 @@
+//
+// ********************************************************************
+// * License and Disclaimer                                           *
+// *                                                                  *
+// * The  Geant4 software  is  copyright of the Copyright Holders  of *
+// * the Geant4 Collaboration.  It is provided  under  the terms  and *
+// * conditions of the Geant4 Software License,  included in the file *
+// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * include a list of copyright holders.                             *
+// *                                                                  *
+// * Neither the authors of this software system, nor their employing *
+// * institutes,nor the agencies providing financial support for this *
+// * work  make  any representation or  warranty, express or implied, *
+// * regarding  this  software system or assume any liability for its *
+// * use.  Please see the license in the file  LICENSE  and URL above *
+// * for the full disclaimer and the limitation of liability.         *
+// *                                                                  *
+// * This  code  implementation is the result of  the  scientific and *
+// * technical work of the GEANT4 collaboration.                      *
+// * By using,  copying,  modifying or  distributing the software (or *
+// * any work based  on the software)  you  agree  to acknowledge its *
+// * use  in  resulting  scientific  publications,  and indicate your *
+// * acceptance of all terms of the Geant4 Software license.          *
+// ********************************************************************
+//
+// $Id: G4SimpleLocator.cc,v 1.5 2008/12/11 10:27:58 tnikitin Exp $
+// GEANT4 tag $Name: geant4-09-02 $
+//
+// Class G4SimpleLocator implementation
+//
+// 27.10.08 - Tatiana Nikitina.
+// ---------------------------------------------------------------------------
+
+#include <iomanip>
+
+#include "G4ios.hh"
+#include "G4SimpleLocator.hh"
+
+G4SimpleLocator::G4SimpleLocator(G4Navigator *theNavigator)
+  : G4VIntersectionLocator(theNavigator)
+{
+}      
+
+G4SimpleLocator::~G4SimpleLocator()
+{
+}
+
+// --------------------------------------------------------------------------
+// G4bool G4PropagatorInField::LocateIntersectionPoint( 
+//        const G4FieldTrack&       CurveStartPointVelocity,   // A
+//        const G4FieldTrack&       CurveEndPointVelocity,     // B
+//        const G4ThreeVector&      TrialPoint,                // E
+//              G4FieldTrack&       IntersectedOrRecalculated  // Output
+//              G4bool&             recalculated )             // Out
+// --------------------------------------------------------------------------
+//
+// Function that returns the intersection of the true path with the surface
+// of the current volume (either the external one or the inner one with one
+// of the daughters:
+//
+//     A = Initial point
+//     B = another point 
+//
+// Both A and B are assumed to be on the true path:
+//
+//     E is the first point of intersection of the chord AB with 
+//     a volume other than A  (on the surface of A or of a daughter)
+//
+// Convention of Use :
+//     i) If it returns "true", then IntersectionPointVelocity is set
+//       to the approximate intersection point.
+//    ii) If it returns "false", no intersection was found.
+//          The validity of IntersectedOrRecalculated depends on 'recalculated'
+//        a) if latter is false, then IntersectedOrRecalculated is invalid. 
+//        b) if latter is true,  then IntersectedOrRecalculated is
+//             the new endpoint, due to a re-integration.
+// --------------------------------------------------------------------------
+// NOTE: implementation taken from G4PropagatorInField
+//
+G4bool G4SimpleLocator::EstimateIntersectionPoint( 
+         const  G4FieldTrack&       CurveStartPointVelocity,     // A
+         const  G4FieldTrack&       CurveEndPointVelocity,       // B
+         const  G4ThreeVector&      TrialPoint,                  // E
+                G4FieldTrack&       IntersectedOrRecalculatedFT, // Output
+                G4bool&             recalculatedEndPoint,        // Out
+                G4double            &fPreviousSafety,            //In/Out
+                G4ThreeVector       &fPreviousSftOrigin)         //In/Out
+{
+  // Find Intersection Point ( A, B, E )  of true path AB - start at E.
+
+  G4bool found_approximate_intersection = false;
+  G4bool there_is_no_intersection       = false;
+  
+  G4FieldTrack  CurrentA_PointVelocity = CurveStartPointVelocity; 
+  G4FieldTrack  CurrentB_PointVelocity = CurveEndPointVelocity;
+  G4ThreeVector CurrentE_Point = TrialPoint;
+  G4FieldTrack  ApproxIntersecPointV(CurveEndPointVelocity); // FT-Def-Construct
+  G4double      NewSafety = 0.0;
+  G4bool last_AF_intersection = false;
+  G4bool final_section = true;  // Shows whether current section is last
+                                // (i.e. B=full end)
+  recalculatedEndPoint = false; 
+
+  G4bool restoredFullEndpoint = false;
+
+  G4int substep_no = 0;
+
+  // Limits for substep number
+  //
+  const G4int max_substeps  = 100000000;  // Test 120  (old value 100 )
+  const G4int warn_substeps = 1000;       //      100  
+
+  // Statistics for substeps
+  //
+  static G4int max_no_seen= -1; 
+  static G4int trigger_substepno_print= warn_substeps - 20;
+ 
+#ifdef G4DEBUG_FIELD
+  static G4double tolerance= 1.0e-8; 
+  G4ThreeVector  StartPosition= CurveStartPointVelocity.GetPosition(); 
+  if( (TrialPoint - StartPosition).mag() < tolerance * mm ) 
+  {
+     G4cerr << "WARNING - G4SimpleLocator::EstimateIntersectionPoint()"
+            << G4endl
+            << "          Intermediate F point is on top of starting point A."
+            << G4endl;
+     G4Exception("G4SimpleLocator::EstimateIntersectionPoint()", 
+                 "IntersectionPointIsAtStart", JustWarning,
+                 "Intersection point F is exactly at start point A." ); 
+  }
+#endif
+
+  do 
+  {
+     G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();  
+     G4ThreeVector Point_B = CurrentB_PointVelocity.GetPosition();
+       
+     // F = a point on true AB path close to point E 
+     // (the closest if possible)
+     //
+     ApproxIntersecPointV = GetChordFinderFor()
+                            ->ApproxCurvePointV( CurrentA_PointVelocity, 
+                                                 CurrentB_PointVelocity, 
+                                                 CurrentE_Point,
+                                                 GetEpsilonStepFor());
+       //  The above method is the key & most intuitive part ...
+      
+#ifdef G4DEBUG_FIELD
+     if( ApproxIntersecPointV.GetCurveLength() > 
+         CurrentB_PointVelocity.GetCurveLength() * (1.0 + tolerance) )
+     {
+       G4cerr << "ERROR - G4SimpleLocator::EstimateIntersectionPoint()"
+              << G4endl
+              << "        Intermediate F point is more advanced than"
+              << " endpoint B." << G4endl;
+       G4Exception("G4SimpleLocator::EstimateIntersectionPoint()", 
+                   "IntermediatePointConfusion", FatalException,
+                   "Intermediate F point is past end B point" ); 
+     }
+#endif
+
+     G4ThreeVector CurrentF_Point= ApproxIntersecPointV.GetPosition();
+
+     // First check whether EF is small - then F is a good approx. point 
+     // Calculate the length and direction of the chord AF
+     //
+     G4ThreeVector  ChordEF_Vector = CurrentF_Point - CurrentE_Point;
+
+     if ( ChordEF_Vector.mag2() <= sqr(GetDeltaIntersectionFor()) )
+     {
+       found_approximate_intersection = true;
+        
+       // Create the "point" return value
+       //
+
+       IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+       IntersectedOrRecalculatedFT.SetPosition( CurrentE_Point );
+
+       if ( GetAdjustementOfFoundIntersection() )
+       {
+         // Try to Get Correction of IntersectionPoint using SurfaceNormal()
+         //  
+         G4ThreeVector IP;
+         G4ThreeVector MomentumDir= ApproxIntersecPointV.GetMomentumDirection();
+         G4bool goodCorrection = AdjustmentOfFoundIntersection( Point_A,
+                                   CurrentE_Point, CurrentF_Point, MomentumDir,
+                                   last_AF_intersection, IP, NewSafety,
+                                   fPreviousSafety, fPreviousSftOrigin );
+
+         if(goodCorrection)
+         {
+           IntersectedOrRecalculatedFT = ApproxIntersecPointV;
+           IntersectedOrRecalculatedFT.SetPosition(IP);
+         }
+       }
+
+       // Note: in order to return a point on the boundary, 
+       //       we must return E. But it is F on the curve.
+       //       So we must "cheat": we are using the position at point E
+       //       and the velocity at point F !!!
+       //
+       // This must limit the length we can allow for displacement!
+     }
+     else  // E is NOT close enough to the curve (ie point F)
+     {
+       // Check whether any volumes are encountered by the chord AF
+       // ---------------------------------------------------------
+       // First relocate to restore any Voxel etc information
+       // in the Navigator before calling ComputeStep()
+       //
+       GetNavigatorFor()->LocateGlobalPointWithinVolume( Point_A );
+
+       G4ThreeVector PointG;   // Candidate intersection point
+       G4double stepLengthAF; 
+       G4bool Intersects_AF = IntersectChord( Point_A,   CurrentF_Point,
+                                              NewSafety,fPreviousSafety,
+                                              fPreviousSftOrigin,
+                                              stepLengthAF,
+                                              PointG );
+       last_AF_intersection = Intersects_AF;
+       if( Intersects_AF )
+       {
+         // G is our new Candidate for the intersection point.
+         // It replaces  "E" and we will repeat the test to see if
+         // it is a good enough approximate point for us.
+         //       B    <- F
+         //       E    <- G
+
+         CurrentB_PointVelocity = ApproxIntersecPointV;
+         CurrentE_Point = PointG;  
+
+         // By moving point B, must take care if current
+         // AF has no intersection to try current FB!!
+         //
+         final_section= false; 
+          
+#ifdef G4VERBOSE
+         if( fVerboseLevel > 3 )
+         {
+           G4cout << "G4PiF::LI> Investigating intermediate point"
+                  << " at s=" << ApproxIntersecPointV.GetCurveLength()
+                  << " on way to full s="
+                  << CurveEndPointVelocity.GetCurveLength() << G4endl;
+         }
+#endif
+       }
+       else  // not Intersects_AF
+       {  
+         // In this case:
+         // There is NO intersection of AF with a volume boundary.
+         // We must continue the search in the segment FB!
+         //
+         GetNavigatorFor()->LocateGlobalPointWithinVolume( CurrentF_Point );
+
+         G4double stepLengthFB;
+         G4ThreeVector PointH;
+
+         // Check whether any volumes are encountered by the chord FB
+         // ---------------------------------------------------------
+
+         G4bool Intersects_FB = IntersectChord( CurrentF_Point, Point_B, 
+                                                NewSafety,fPreviousSafety,
+                                                fPreviousSftOrigin,
+                                                stepLengthFB,
+                                                PointH );
+         if( Intersects_FB )
+         { 
+           // There is an intersection of FB with a volume boundary
+           // H <- First Intersection of Chord FB 
+
+           // H is our new Candidate for the intersection point.
+           // It replaces  "E" and we will repeat the test to see if
+           // it is a good enough approximate point for us.
+
+           // Note that F must be in volume volA  (the same as A)
+           // (otherwise AF would meet a volume boundary!)
+           //   A    <- F 
+           //   E    <- H
+           //
+           CurrentA_PointVelocity = ApproxIntersecPointV;
+           CurrentE_Point = PointH;
+         }
+         else  // not Intersects_FB
+         {
+           // There is NO intersection of FB with a volume boundary
+
+           if( final_section  )
+           {
+             // If B is the original endpoint, this means that whatever
+             // volume(s) intersected the original chord, none touch the
+             // smaller chords we have used.
+             // The value of 'IntersectedOrRecalculatedFT' returned is
+             // likely not valid 
+              
+             there_is_no_intersection = true;   // real final_section
+           }
+           else
+           {
+             // We must restore the original endpoint
+
+             CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
+             CurrentB_PointVelocity = CurveEndPointVelocity;
+             restoredFullEndpoint = true;
+           }
+         } // Endif (Intersects_FB)
+       } // Endif (Intersects_AF)
+
+       // Ensure that the new endpoints are not further apart in space
+       // than on the curve due to different errors in the integration
+       //
+       G4double linDistSq, curveDist; 
+       linDistSq = ( CurrentB_PointVelocity.GetPosition() 
+                   - CurrentA_PointVelocity.GetPosition() ).mag2(); 
+       curveDist = CurrentB_PointVelocity.GetCurveLength()
+                   - CurrentA_PointVelocity.GetCurveLength();
+
+       // Change this condition for very strict parameters of propagation 
+       //
+       if( curveDist*curveDist*(1+2* GetEpsilonStepFor()) < linDistSq )
+       {
+         // Re-integrate to obtain a new B
+         //
+         G4FieldTrack newEndPointFT =
+                 ReEstimateEndpoint( CurrentA_PointVelocity,
+                                     CurrentB_PointVelocity,
+                                     linDistSq,    // to avoid recalculation
+                                     curveDist );
+         G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
+         CurrentB_PointVelocity = newEndPointFT;
+
+         if( (final_section)) // real final section
+         {
+           recalculatedEndPoint = true;
+           IntersectedOrRecalculatedFT = newEndPointFT;
+             // So that we can return it, if it is the endpoint!
+         }
+       }
+       if( curveDist < 0.0 )
+       {
+         G4cerr << "ERROR - G4SimpleLocator::EstimateIntersectionPoint()"
+                << G4endl
+                << "        Error in advancing propagation." << G4endl;
+         fVerboseLevel = 5; // Print out a maximum of information
+         printStatus( CurrentA_PointVelocity,  CurrentB_PointVelocity,
+                      -1.0, NewSafety,  substep_no );
+         G4cerr << "        Point A (start) is " << CurrentA_PointVelocity
+                << G4endl;
+         G4cerr << "        Point B (end)   is " << CurrentB_PointVelocity
+                << G4endl;
+         G4cerr << "        Curve distance is " << curveDist << G4endl;
+         G4cerr << G4endl
+                << "The final curve point is not further along"
+                << " than the original!" << G4endl;
+
+         if( recalculatedEndPoint )
+         {
+           G4cerr << "Recalculation of EndPoint was called with fEpsStep= "
+                  << GetEpsilonStepFor() << G4endl;
+         }
+         G4cerr.precision(20);
+         G4cerr << " Point A (Curve start)   is " << CurveStartPointVelocity
+                << G4endl;
+         G4cerr << " Point B (Curve   end)   is " << CurveEndPointVelocity
+                << G4endl;
+         G4cerr << " Point A (Current start) is " << CurrentA_PointVelocity
+                << G4endl;
+         G4cerr << " Point B (Current end)   is " << CurrentB_PointVelocity
+                << G4endl;
+         G4cerr << " Point E (Trial Point)   is " << CurrentE_Point
+                << G4endl;
+         G4cerr << " Point F (Intersection)  is " << ApproxIntersecPointV
+                << G4endl;
+         G4cerr << "        LocateIntersection parameters are : Substep no= "
+                << substep_no << G4endl;
+
+         G4Exception("G4SimpleLocator::EstimateIntersectionPoint()",
+                     "FatalError", FatalException,
+                     "Error in advancing propagation.");
+       }
+
+       if(restoredFullEndpoint)
+       {
+         final_section = restoredFullEndpoint;
+         restoredFullEndpoint = false;
+       }
+     } // EndIf ( E is close enough to the curve, ie point F. )
+       // tests ChordAF_Vector.mag() <= maximum_lateral_displacement 
+
+#ifdef G4DEBUG_LOCATE_INTERSECTION  
+     if( substep_no >= trigger_substepno_print )
+     {
+       G4cout << "Difficulty in converging in "
+              << "G4SimpleLocator::EstimateIntersectionPoint():"
+              << G4endl
+              << "    Substep no = " << substep_no << G4endl;
+       if( substep_no == trigger_substepno_print )
+       {
+         printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                      -1.0, NewSafety, 0);
+       }
+       G4cout << " State of point A: "; 
+       printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                    -1.0, NewSafety, substep_no-1, 0);
+       G4cout << " State of point B: "; 
+       printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                    -1.0, NewSafety, substep_no);
+     }
+#endif
+     substep_no++; 
+
+  } while ( ( ! found_approximate_intersection )
+           && ( ! there_is_no_intersection )     
+           && ( substep_no <= max_substeps) ); // UNTIL found or failed
+
+  if( substep_no > max_no_seen )
+  {
+    max_no_seen = substep_no; 
+    if( max_no_seen > warn_substeps )
+    {
+      trigger_substepno_print = max_no_seen-20; // Want to see last 20 steps 
+    } 
+  }
+
+  if(  ( substep_no >= max_substeps)
+      && !there_is_no_intersection
+      && !found_approximate_intersection )
+  {
+    G4cerr << "WARNING - G4SimpleLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cerr << "          Abandoning effort to intersect. " << G4endl;
+    G4cerr << "          Information on start & current step follows in cout."
+           << G4endl;
+    G4cout << "WARNING - G4SimpleLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Convergence is requiring too many substeps: "
+           << substep_no << G4endl;
+    G4cout << "          Found intersection = "
+           << found_approximate_intersection << G4endl
+           << "          Intersection exists = "
+           << !there_is_no_intersection << G4endl;
+    G4cout << "          Start and Endpoint of Requested Step:" << G4endl;
+    printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
+                 -1.0, NewSafety, 0);
+    G4cout << G4endl;
+    G4cout << "          'Bracketing' starting and endpoint of current Sub-Step"
+           << G4endl;
+    printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
+                 -1.0, NewSafety, substep_no-1);
+    printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
+                 -1.0, NewSafety, substep_no);
+    G4cout << G4endl;
+    G4cout.precision( 10 ); 
+    G4double done_len = CurrentA_PointVelocity.GetCurveLength(); 
+    G4double full_len = CurveEndPointVelocity.GetCurveLength();
+    G4cout << "ERROR - G4SimpleLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "        Undertaken only length: " << done_len
+           << " out of " << full_len << " required." << G4endl;
+    G4cout << "        Remaining length = " << full_len - done_len << G4endl; 
+
+    G4Exception("G4SimpleLocator::EstimateIntersectionPoint()",
+                "UnableToLocateIntersection", FatalException,
+                "Too many substeps while trying to locate intersection.");
+  }
+  else if( substep_no >= warn_substeps )
+  {  
+    G4int oldprc= G4cout.precision( 10 ); 
+    G4cout << "WARNING - G4SimpleLocator::EstimateIntersectionPoint()"
+           << G4endl
+           << "          Undertaken length: "  
+           << CurrentB_PointVelocity.GetCurveLength(); 
+    G4cout << " - Needed: "  << substep_no << " substeps." << G4endl
+           << "          Warning level = " << warn_substeps
+           << " and maximum substeps = " << max_substeps << G4endl;
+    G4Exception("G4SimpleLocator::EstimateIntersectionPoint()",
+                "DifficultyToLocateIntersection", JustWarning,
+                "Many substeps while trying to locate intersection.");
+    G4cout.precision( oldprc ); 
+  }
+  return  !there_is_no_intersection; //  Success or failure
+}

source/geometry/navigation/src/G4TransportationManager.cc

@@ -25,7 +25,7 @@
 //
 //
 // $Id: G4TransportationManager.cc,v 1.15 2007/04/12 11:51:48 vnivanch Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // G4TransportationManager 

source/geometry/navigation/src/G4VIntersectionLocator.cc

@@ -0,0 +1,394 @@
+//
+// ********************************************************************
+// * License and Disclaimer                                           *
+// *                                                                  *
+// * The  Geant4 software  is  copyright of the Copyright Holders  of *
+// * the Geant4 Collaboration.  It is provided  under  the terms  and *
+// * conditions of the Geant4 Software License,  included in the file *
+// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * include a list of copyright holders.                             *
+// *                                                                  *
+// * Neither the authors of this software system, nor their employing *
+// * institutes,nor the agencies providing financial support for this *
+// * work  make  any representation or  warranty, express or implied, *
+// * regarding  this  software system or assume any liability for its *
+// * use.  Please see the license in the file  LICENSE  and URL above *
+// * for the full disclaimer and the limitation of liability.         *
+// *                                                                  *
+// * This  code  implementation is the result of  the  scientific and *
+// * technical work of the GEANT4 collaboration.                      *
+// * By using,  copying,  modifying or  distributing the software (or *
+// * any work based  on the software)  you  agree  to acknowledge its *
+// * use  in  resulting  scientific  publications,  and indicate your *
+// * acceptance of all terms of the Geant4 Software license.          *
+// ********************************************************************
+//
+// $Id: G4VIntersectionLocator.cc,v 1.4 2008/11/14 18:26:35 gcosmo Exp $
+// GEANT4 tag $Name: geant4-09-02 $
+//
+// Class G4VIntersectionLocator implementation
+//
+// 27.10.08 - John Apostolakis, Tatiana Nikitina.
+// ---------------------------------------------------------------------------
+ 
+#include <iomanip>
+
+#include "globals.hh"
+#include "G4ios.hh"
+#include "G4VIntersectionLocator.hh"
+#include "G4GeometryTolerance.hh"
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Constructor
+//
+G4VIntersectionLocator:: G4VIntersectionLocator(G4Navigator *theNavigator)
+{
+  kCarTolerance = G4GeometryTolerance::GetInstance()->GetSurfaceTolerance();
+  fiNavigator = theNavigator;
+  fVerboseLevel = 0;
+  fUseNormalCorrection = false;
+  fHelpingNavigator = new G4Navigator();
+}      
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Destructor.
+//
+G4VIntersectionLocator::~G4VIntersectionLocator()
+{
+  delete fHelpingNavigator;
+}
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Dumps status of propagator.
+//
+void
+G4VIntersectionLocator::printStatus( const G4FieldTrack&        StartFT,
+                                     const G4FieldTrack&        CurrentFT, 
+                                           G4double             requestStep, 
+                                           G4double             safety,
+                                           G4int                stepNo)
+{
+  const G4int verboseLevel= fVerboseLevel;
+  const G4ThreeVector StartPosition       = StartFT.GetPosition();
+  const G4ThreeVector StartUnitVelocity   = StartFT.GetMomentumDir();
+  const G4ThreeVector CurrentPosition     = CurrentFT.GetPosition();
+  const G4ThreeVector CurrentUnitVelocity = CurrentFT.GetMomentumDir();
+
+  G4double step_len = CurrentFT.GetCurveLength() - StartFT.GetCurveLength();
+      
+  if( ((stepNo == 0) && (verboseLevel <3)) || (verboseLevel >= 3) )
+  {
+    static G4int noPrecision= 4;
+    G4cout.precision(noPrecision);
+    // G4cout.setf(ios_base::fixed,ios_base::floatfield);
+    G4cout << std::setw( 6)  << " " 
+           << std::setw( 25) << " Current Position  and  Direction" << " "
+           << G4endl; 
+    G4cout << std::setw( 5) << "Step#" 
+           << std::setw(10) << "  s  " << " "
+           << std::setw(10) << "X(mm)" << " "
+           << std::setw(10) << "Y(mm)" << " "  
+           << std::setw(10) << "Z(mm)" << " "
+           << std::setw( 7) << " N_x " << " "
+           << std::setw( 7) << " N_y " << " "
+           << std::setw( 7) << " N_z " << " " ;
+    //            << G4endl; 
+    G4cout     // << " >>> "
+           << std::setw( 7) << " Delta|N|" << " "
+      //   << std::setw( 7) << " Delta(N_z) " << " "
+           << std::setw( 9) << "StepLen" << " "  
+           << std::setw(12) << "StartSafety" << " "  
+           << std::setw( 9) << "PhsStep" << " ";  
+  
+    G4cout << G4endl;
+  }
+  if((stepNo == 0) && (verboseLevel <=3))
+  {
+    // Recurse to print the start values
+    //
+    printStatus( StartFT, StartFT, -1.0, safety, -1);
+  }
+  if( verboseLevel <= 3 )
+  {
+    if( stepNo >= 0)
+    {
+       G4cout << std::setw( 4) << stepNo << " ";
+    }
+    else
+    {
+       G4cout << std::setw( 5) << "Start" ;
+    }
+    G4cout.precision(8);
+    G4cout << std::setw(10) << CurrentFT.GetCurveLength() << " "; 
+    G4cout.precision(8);
+    G4cout << std::setw(10) << CurrentPosition.x() << " "
+           << std::setw(10) << CurrentPosition.y() << " "
+           << std::setw(10) << CurrentPosition.z() << " ";
+    G4cout.precision(4);
+    G4cout << std::setw( 7) << CurrentUnitVelocity.x() << " "
+           << std::setw( 7) << CurrentUnitVelocity.y() << " "
+           << std::setw( 7) << CurrentUnitVelocity.z() << " ";
+     //  G4cout << G4endl; 
+     //     G4cout << " >>> " ; 
+     G4cout.precision(3); 
+     G4cout << std::setw( 7)
+            << CurrentFT.GetMomentum().mag()- StartFT.GetMomentum().mag()
+            << " "; 
+     //   << std::setw( 7)
+     //   << CurrentUnitVelocity.z() - InitialUnitVelocity.z() << " ";
+     G4cout << std::setw( 9) << step_len << " "; 
+     G4cout << std::setw(12) << safety << " ";
+     if( requestStep != -1.0 )
+     {
+       G4cout << std::setw( 9) << requestStep << " ";
+     }
+     else
+     {
+       G4cout << std::setw( 9) << "Init/NotKnown" << " "; 
+     }
+     G4cout << G4endl;
+   }
+   else // if( verboseLevel > 3 )
+   {
+     //  Multi-line output
+       
+     G4cout << "Step taken was " << step_len  
+            << " out of PhysicalStep= " <<  requestStep << G4endl;
+     G4cout << "Final safety is: " << safety << G4endl;
+
+     G4cout << "Chord length = " << (CurrentPosition-StartPosition).mag()
+            << G4endl;
+     G4cout << G4endl; 
+   }
+}
+
+///////////////////////////////////////////////////////////////////////////
+//
+// ReEstimateEndPoint.
+//
+G4FieldTrack G4VIntersectionLocator::
+ReEstimateEndpoint( const G4FieldTrack &CurrentStateA,  
+                    const G4FieldTrack &EstimatedEndStateB,
+                          G4double      linearDistSq,
+                          G4double      curveDist )
+{  
+  G4FieldTrack newEndPoint( CurrentStateA );
+  G4MagInt_Driver* integrDriver= GetChordFinderFor()->GetIntegrationDriver(); 
+
+  G4FieldTrack retEndPoint( CurrentStateA );
+  G4bool goodAdvance;
+  G4int  itrial=0;
+  const G4int no_trials= 20;
+
+  G4double endCurveLen= EstimatedEndStateB.GetCurveLength();
+  do
+  {
+     G4double currentCurveLen= newEndPoint.GetCurveLength();
+     G4double advanceLength= endCurveLen - currentCurveLen ; 
+     if (std::abs(advanceLength)<kCarTolerance)
+     {
+       advanceLength=(EstimatedEndStateB.GetPosition()
+                     -newEndPoint.GetPosition()).mag();
+     }
+     goodAdvance= 
+       integrDriver->AccurateAdvance(newEndPoint, advanceLength,
+                                     GetEpsilonStepFor());
+  }
+  while( !goodAdvance && (++itrial < no_trials) );
+
+  if( goodAdvance )
+  {
+    retEndPoint= newEndPoint; 
+  }
+  else
+  {
+    retEndPoint= EstimatedEndStateB; // Could not improve without major work !!
+  }
+
+  //  All the work is done
+  //  below are some diagnostics only -- before the return!
+  // 
+  static const G4String MethodName("G4VIntersectionLocator::ReEstimateEndpoint");
+
+#ifdef G4VERBOSE
+  G4int  latest_good_trials=0;
+  if( itrial > 1)
+  {
+    if( fVerboseLevel > 0 )
+    {
+      G4cout << MethodName << " called - goodAdv= " << goodAdvance
+             << " trials = " << itrial
+             << " previous good= " << latest_good_trials
+             << G4endl;
+    }
+    latest_good_trials=0; 
+  }
+  else
+  {   
+    latest_good_trials++; 
+  }
+#endif
+
+#ifdef G4DEBUG_FIELD
+  G4double lengthDone = newEndPoint.GetCurveLength() 
+                      - CurrentStateA.GetCurveLength(); 
+  if( !goodAdvance )
+  {
+    if( fVerboseLevel >= 3 )
+    {
+      G4cout << MethodName << "> AccurateAdvance failed " ;
+      G4cout << " in " << itrial << " integration trials/steps. " << G4endl;
+      G4cout << " It went only " << lengthDone << " instead of " << curveDist
+             << " -- a difference of " << curveDist - lengthDone  << G4endl;
+      G4cout << " ReEstimateEndpoint> Reset endPoint to original value!"
+             << G4endl;
+    }
+  }
+
+  static G4int noInaccuracyWarnings = 0; 
+  G4int maxNoWarnings = 10;
+  if (  (noInaccuracyWarnings < maxNoWarnings ) 
+       || (fVerboseLevel > 1) )
+    {
+      G4cerr << "G4PropagatorInField::LocateIntersectionPoint():"
+             << G4endl
+             << " Warning: Integration inaccuracy requires" 
+             <<   " an adjustment in the step's endpoint."  << G4endl
+             << "   Two mid-points are further apart than their"
+             <<   " curve length difference"                << G4endl 
+             << "   Dist = "       << std::sqrt(linearDistSq)
+             << " curve length = " << curveDist             << G4endl; 
+      G4cerr << " Correction applied is " 
+             << (newEndPoint.GetPosition()-EstimatedEndStateB.GetPosition()).mag()
+             << G4endl;
+    }
+#else
+  // Statistics on the RMS value of the corrections
+
+  static G4int    noCorrections=0;
+  static G4double sumCorrectionsSq = 0;
+  noCorrections++; 
+  if( goodAdvance )
+  {
+    sumCorrectionsSq += (EstimatedEndStateB.GetPosition() - 
+                         newEndPoint.GetPosition()).mag2();
+  }
+  linearDistSq -= curveDist; // To use linearDistSq ... !
+#endif
+
+  return retEndPoint;
+}
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Method for finding SurfaceNormal of Intersecting Solid 
+//
+G4ThreeVector G4VIntersectionLocator::
+GetLocalSurfaceNormal(const G4ThreeVector &CurrentE_Point, G4bool &validNormal)
+{
+  G4ThreeVector Normal(G4ThreeVector(0,0,0));
+  G4VPhysicalVolume* located;
+
+  validNormal = false;
+  fHelpingNavigator->SetWorldVolume(GetNavigatorFor()->GetWorldVolume());
+  located = fHelpingNavigator->LocateGlobalPointAndSetup( CurrentE_Point );
+  G4TouchableHistoryHandle aTouchable = fHelpingNavigator
+                                      ->CreateTouchableHistoryHandle();
+  G4ThreeVector localPosition = aTouchable->GetHistory()
+                ->GetTopTransform().TransformPoint(CurrentE_Point);
+
+  if( located != 0)
+  { 
+    if (located->GetLogicalVolume()
+        ->GetSolid()->Inside(localPosition)==kSurface)
+    {
+      Normal = located->GetLogicalVolume()
+                      ->GetSolid()->SurfaceNormal(localPosition);
+      validNormal = true;
+    }
+  }
+
+  return Normal;
+}
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Adjustment of Found Intersection
+//
+G4bool G4VIntersectionLocator::
+AdjustmentOfFoundIntersection( const G4ThreeVector &CurrentA_Point,
+                               const G4ThreeVector &CurrentE_Point, 
+                               const G4ThreeVector &CurrentF_Point,
+                               const G4ThreeVector &MomentumDir,
+                               const G4bool         IntersectAF,
+                                     G4ThreeVector &IntersectionPoint,  // I/O
+                                     G4double      &NewSafety,          // I/O 
+                                     G4double      &fPreviousSafety,    // I/O
+                                     G4ThreeVector &fPreviousSftOrigin )// I/O
+{     
+  G4double dist,lambda;
+  G4ThreeVector Normal, NewPoint, Point_G;
+  G4bool goodAdjust=false, Intersects_FP=false, validNormal=false;
+
+  // Get SurfaceNormal of Intersecting Solid
+  //
+  Normal=GetLocalSurfaceNormal(CurrentE_Point,validNormal);
+  if(!validNormal) { return false; }
+
+  // Intersection between Line and Plane
+  //
+  G4double n_d_m = Normal.dot(MomentumDir);
+  if ( std::abs(n_d_m)<kCarTolerance )
+  {
+    if ( fVerboseLevel>1 )
+    {
+      G4cerr << "WARNING - "
+             << "G4VIntersectionLocator::AdjustementOfFoundIntersection()"
+             << G4endl
+             << "        No intersection. Parallels lines!" << G4endl;
+        return false;
+    }
+    lambda =- Normal.dot(CurrentF_Point-CurrentE_Point)/n_d_m;
+
+    // New candidate for Intersection
+    //
+    NewPoint = CurrentF_Point+lambda*MomentumDir;
+
+    // Distance from CurrentF to Calculated Intersection
+    //
+    dist = std::abs(lambda);
+
+    if ( dist<kCarTolerance*0.001 )  { return false; }
+
+    // Calculation of new intersection point on the path.
+    //
+    if ( IntersectAF )  //  First part intersects
+    {
+      G4double stepLengthFP; 
+      G4ThreeVector Point_P = CurrentA_Point;
+      GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_P);
+      Intersects_FP = IntersectChord( Point_P, NewPoint, NewSafety,
+                                      fPreviousSafety, fPreviousSftOrigin,
+                                      stepLengthFP, Point_G );
+
+    }
+    else   // Second part intersects
+    {      
+      G4double stepLengthFP; 
+      GetNavigatorFor()->LocateGlobalPointWithinVolume(CurrentF_Point );
+      Intersects_FP = IntersectChord( CurrentF_Point, NewPoint, NewSafety,
+                                      fPreviousSafety, fPreviousSftOrigin,
+                                      stepLengthFP, Point_G );
+    }
+    if ( Intersects_FP )
+    {
+      goodAdjust = true;
+      IntersectionPoint = Point_G;              
+    }
+  }
+
+  return goodAdjust;
+}

source/geometry/navigation/src/G4VoxelNavigation.cc

@@ -24,8 +24,8 @@
 // ********************************************************************
 //
 //
-// $Id: G4VoxelNavigation.cc,v 1.7 2007/05/11 13:43:59 gcosmo Exp $
-// GEANT4 tag $Name: geant4-09-01 $
+// $Id: G4VoxelNavigation.cc,v 1.9 2008/11/14 18:26:35 gcosmo Exp $
+// GEANT4 tag $Name: geant4-09-02 $
 //
 //
 // class G4VoxelNavigation Implementation
@@ -253,9 +253,9 @@ G4VoxelNavigation::ComputeStep( const G4ThreeVector& localPoint,
                 EInside insideIntPt= sampleSolid->Inside(intersectionPoint); 
                 G4String solidResponse = "-kInside-";
                 if (insideIntPt == kOutside)
-                  solidResponse = "-kOutside-";
+                  { solidResponse = "-kOutside-"; }
                 else if (insideIntPt == kSurface)
-                  solidResponse = "-kSurface-";
+                  { solidResponse = "-kSurface-"; }
                 if( fVerbose == 1 )
                 {
                   G4cout << "*** G4VoxelNavigation::ComputeStep(): ***"<<G4endl
@@ -265,6 +265,20 @@ G4VoxelNavigation::ComputeStep( const G4ThreeVector& localPoint,
                          << "    For point p: " << intersectionPoint
                          << ", considered as 'intersection' point." << G4endl;
                 }
+                G4double safetyIn= -1, safetyOut= -1;  //  Set to invalid values
+                G4double newDistIn= -1,  newDistOut= -1;
+                if( insideIntPt != kInside )
+                {
+                  safetyIn= sampleSolid->DistanceToIn(intersectionPoint);
+                  newDistIn= sampleSolid->DistanceToIn(intersectionPoint,
+                                                       sampleDirection);
+                }
+                if( insideIntPt != kOutside )
+                {
+                  safetyOut= sampleSolid->DistanceToOut(intersectionPoint);
+                  newDistOut= sampleSolid->DistanceToOut(intersectionPoint,
+                                                         sampleDirection);
+                }
                 if( insideIntPt != kSurface )
                 {
                   G4int oldcoutPrec = G4cout.precision(16); 
@@ -276,19 +290,54 @@ G4VoxelNavigation::ComputeStep( const G4ThreeVector& localPoint,
                          << sampleStep << " yet returns " << solidResponse
                          << " for this point !" << G4endl; 
                   G4cout << "          Point = " << intersectionPoint << G4endl;
+                  G4cout << "          Safety values: " << G4endl;
                   if ( insideIntPt != kInside )
-                    G4cout << "        DistanceToIn(p) = " 
-                           << sampleSolid->DistanceToIn(intersectionPoint)
+                  {
+                    G4cout << "          DistanceToIn(p)  = " << safetyIn
                            << G4endl;
-                  if ( insideIntPt != kOutside ) 
-                    G4cout << "        DistanceToOut(p) = " 
-                           << sampleSolid->DistanceToOut(intersectionPoint)
+                  }
+                  if ( insideIntPt != kOutside )
+                  {
+                    G4cout << "          DistanceToOut(p) = " << safetyOut
                            << G4endl;
+                  }
                   G4Exception("G4VoxelNavigation::ComputeStep()", 
                               "InaccurateDistanceToIn", JustWarning,
-                              "Navigator gets conflicting response from Solid.");
+                              "Conflicting response from Solid.");
                   G4cout.precision(oldcoutPrec);
                 }
+                else
+                {  
+                  // If it is on the surface, *ensure* that either DistanceToIn
+                  // or DistanceToOut returns a finite value ( >= Tolerance).
+                  //
+                  if( std::max( newDistIn, newDistOut ) <= kCarTolerance )
+                  { 
+                    G4cout << "ERROR - G4VoxelNavigation::ComputeStep()"
+                       << G4endl
+                       << "  Identified point for which the solid " 
+                       << sampleSolid->GetName() << G4endl
+                       << "  has MAJOR problem:  " << G4endl
+                       << "  --> Both DistanceToIn(p,v) and DistanceToOut(p,v) "
+                       << "return Zero, an equivalent value or negative value."
+                       << G4endl; 
+                    G4cout << "    Solid: " << sampleSolid << G4endl;
+                    G4cout << "    Point p= " << intersectionPoint << G4endl;
+                    G4cout << "    Direction v= " << sampleDirection << G4endl;
+                    G4cout << "    DistanceToIn(p,v)     = " << newDistIn
+                           << G4endl;
+                    G4cout << "    DistanceToOut(p,v,..) = " << newDistOut
+                           << G4endl;
+                    G4cout << "    Safety values: " << G4endl;
+                    G4cout << "      DistanceToIn(p)  = " << safetyIn
+                           << G4endl;
+                    G4cout << "      DistanceToOut(p) = " << safetyOut
+                           << G4endl;
+                    G4Exception("G4VoxelNavigation::ComputeStep()", 
+                              "DistanceToInAndOutAreZero", FatalException,
+                              "Zero from both Solid DistanceIn and Out(p,v).");
+                  }
+                }
               }
 #endif
             }