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Geant4/geometry/navigation/src/G4MultiLevelLocator.cc

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Differences between /geometry/navigation/src/G4MultiLevelLocator.cc (Version 11.3.0) and /geometry/navigation/src/G4MultiLevelLocator.cc (Version 9.4.p1)


  1 //                                                  1 //
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 25 //                                                 25 //
                                                   >>  26 // $Id: G4MultiLevelLocator.cc,v 1.6 2010-07-13 15:59:42 gcosmo Exp $
                                                   >>  27 // GEANT4 tag $Name: geant4-09-04-patch-01 $
                                                   >>  28 //
 26 // Class G4MultiLevelLocator implementation        29 // Class G4MultiLevelLocator implementation
 27 //                                                 30 //
 28 // 27.10.08 - Tatiana Nikitina.                    31 // 27.10.08 - Tatiana Nikitina.
 29 // 04.10.11 - John Apostolakis, revised conver << 
 30 // -------------------------------------------     32 // ---------------------------------------------------------------------------
 31                                                    33 
 32 #include <iomanip>                                 34 #include <iomanip>
 33                                                    35 
 34 #include "G4ios.hh"                                36 #include "G4ios.hh"
 35 #include "G4MultiLevelLocator.hh"                  37 #include "G4MultiLevelLocator.hh"
 36 #include "G4LocatorChangeRecord.hh"            << 
 37 #include "G4LocatorChangeLogger.hh"            << 
 38                                                    38 
 39 G4MultiLevelLocator::G4MultiLevelLocator(G4Nav     39 G4MultiLevelLocator::G4MultiLevelLocator(G4Navigator *theNavigator)
 40   : G4VIntersectionLocator(theNavigator)       <<  40  : G4VIntersectionLocator(theNavigator)
 41 {                                                  41 {
 42   // In case of too slow progress in finding I     42   // In case of too slow progress in finding Intersection Point
 43   // intermediates Points on the Track must be     43   // intermediates Points on the Track must be stored.
 44   // Initialise the array of Pointers [max_dep     44   // Initialise the array of Pointers [max_depth+1] to do this  
 45                                                    45   
 46   G4ThreeVector zeroV(0.0,0.0,0.0);                46   G4ThreeVector zeroV(0.0,0.0,0.0);
 47   for (auto & idepth : ptrInterMedFT)          <<  47   for (G4int idepth=0; idepth<max_depth+1; idepth++ )
 48   {                                                48   {
 49     idepth = new G4FieldTrack( zeroV, zeroV, 0 <<  49     ptrInterMedFT[ idepth ] = new G4FieldTrack( zeroV, zeroV, 0., 0., 0., 0.);
 50   }                                                50   }
 51                                                << 
 52   if (fCheckMode)                              << 
 53   {                                            << 
 54     //  Trial values       Loose         Mediu << 
 55     //  To happen:         Infrequent    Occas << 
 56     SetMaxSteps(150);   //  300             85 << 
 57     SetWarnSteps(80);   //  250             60 << 
 58   }                                            << 
 59 }                                                  51 }      
 60                                                    52 
 61 G4MultiLevelLocator::~G4MultiLevelLocator()        53 G4MultiLevelLocator::~G4MultiLevelLocator()
 62 {                                                  54 {
 63   for (auto & idepth : ptrInterMedFT)          <<  55   for ( G4int idepth=0; idepth<max_depth+1; idepth++)
 64   {                                                56   {
 65     delete idepth;                             <<  57     delete ptrInterMedFT[idepth];
 66   }                                                58   }
 67 #ifdef G4DEBUG_FIELD                           << 
 68   ReportStatistics();                          << 
 69 #endif                                         << 
 70 }                                                  59 }
 71                                                    60 
 72                                                << 
 73 // -------------------------------------------     61 // --------------------------------------------------------------------------
 74 // G4bool G4PropagatorInField::LocateIntersect     62 // G4bool G4PropagatorInField::LocateIntersectionPoint( 
 75 //        const G4FieldTrack&       CurveStart     63 //        const G4FieldTrack&       CurveStartPointVelocity,   // A
 76 //        const G4FieldTrack&       CurveEndPo     64 //        const G4FieldTrack&       CurveEndPointVelocity,     // B
 77 //        const G4ThreeVector&      TrialPoint     65 //        const G4ThreeVector&      TrialPoint,                // E
 78 //              G4FieldTrack&       Intersecte     66 //              G4FieldTrack&       IntersectedOrRecalculated  // Output
 79 //              G4bool&             recalculat     67 //              G4bool&             recalculated )             // Out
 80 // -------------------------------------------     68 // --------------------------------------------------------------------------
 81 //                                                 69 //
 82 // Function that returns the intersection of t     70 // Function that returns the intersection of the true path with the surface
 83 // of the current volume (either the external      71 // of the current volume (either the external one or the inner one with one
 84 // of the daughters:                               72 // of the daughters:
 85 //                                                 73 //
 86 //     A = Initial point                           74 //     A = Initial point
 87 //     B = another point                           75 //     B = another point 
 88 //                                                 76 //
 89 // Both A and B are assumed to be on the true      77 // Both A and B are assumed to be on the true path:
 90 //                                                 78 //
 91 //     E is the first point of intersection of     79 //     E is the first point of intersection of the chord AB with 
 92 //     a volume other than A  (on the surface      80 //     a volume other than A  (on the surface of A or of a daughter)
 93 //                                                 81 //
 94 // Convention of Use :                             82 // Convention of Use :
 95 //     i) If it returns "true", then Intersect     83 //     i) If it returns "true", then IntersectionPointVelocity is set
 96 //       to the approximate intersection point     84 //       to the approximate intersection point.
 97 //    ii) If it returns "false", no intersecti     85 //    ii) If it returns "false", no intersection was found.
 98 //        Potential reasons:                   <<  86 //          The validity of IntersectedOrRecalculated depends on 'recalculated'
 99 //        a) no segment found an intersection  <<  87 //        a) if latter is false, then IntersectedOrRecalculated is invalid. 
100 //        b) too many steps were required - af <<  88 //        b) if latter is true,  then IntersectedOrRecalculated is
101 //           and is returning how far it could <<  89 //             the new endpoint, due to a re-integration.
102 //           (If so, it must set 'recalculated << 
103 //        TODO/idea: add a new flag: 'unfinish << 
104 //                                             << 
105 //        IntersectedOrRecalculated means diff << 
106 //        a) if it is the same curve lenght al << 
107 //            original enpdoint due to the nee << 
108 //        b) if it is at a shorter curve lengt << 
109 //           i.e. as far as it could go, becau << 
110 //        Note: IntersectedOrRecalculated is v << 
111 //       'true'.                               << 
112 // -------------------------------------------     90 // --------------------------------------------------------------------------
113 // NOTE: implementation taken from G4Propagato     91 // NOTE: implementation taken from G4PropagatorInField
114 //                                                 92 //
115 G4bool G4MultiLevelLocator::EstimateIntersecti     93 G4bool G4MultiLevelLocator::EstimateIntersectionPoint( 
116          const  G4FieldTrack&       CurveStart     94          const  G4FieldTrack&       CurveStartPointVelocity,       // A
117          const  G4FieldTrack&       CurveEndPo     95          const  G4FieldTrack&       CurveEndPointVelocity,         // B
118          const  G4ThreeVector&      TrialPoint     96          const  G4ThreeVector&      TrialPoint,                    // E
119                 G4FieldTrack&       Intersecte     97                 G4FieldTrack&       IntersectedOrRecalculatedFT,   // Output
120                 G4bool&             recalculat     98                 G4bool&             recalculatedEndPoint,          // Out
121                 G4double&           previousSa <<  99                 G4double            &fPreviousSafety,              // In/Out
122                 G4ThreeVector&      previousSf << 100                 G4ThreeVector       &fPreviousSftOrigin)           // In/Out
123 {                                                 101 {
124   // Find Intersection Point ( A, B, E )  of t    102   // Find Intersection Point ( A, B, E )  of true path AB - start at E.
125   const char* MethodName= "G4MultiLevelLocator << 103 
126                                                << 
127   G4bool found_approximate_intersection = fals    104   G4bool found_approximate_intersection = false;
128   G4bool there_is_no_intersection       = fals    105   G4bool there_is_no_intersection       = false;
129                                                << 106   
130   G4FieldTrack  CurrentA_PointVelocity = Curve    107   G4FieldTrack  CurrentA_PointVelocity = CurveStartPointVelocity; 
131   G4FieldTrack  CurrentB_PointVelocity = Curve    108   G4FieldTrack  CurrentB_PointVelocity = CurveEndPointVelocity;
132   G4ThreeVector CurrentE_Point = TrialPoint;      109   G4ThreeVector CurrentE_Point = TrialPoint;
133   G4bool        validNormalAtE = false;        << 
134   G4ThreeVector NormalAtEntry;                 << 
135                                                << 
136   G4FieldTrack  ApproxIntersecPointV(CurveEndP    110   G4FieldTrack  ApproxIntersecPointV(CurveEndPointVelocity); // FT-Def-Construct
137   G4bool        validIntersectP= true;   // Is << 
138   G4double      NewSafety = 0.0;                  111   G4double      NewSafety = 0.0;
139   G4bool        last_AF_intersection = false;     112   G4bool        last_AF_intersection = false;   
140                                                   113 
141   auto    integrDriver = GetChordFinderFor()-> << 114   // G4bool final_section= true;  // Shows whether current section is last
142   G4bool  driverReIntegrates = integrDriver->D << 115                                   // (i.e. B=full end)
143                                                << 
144   G4bool first_section = true;                    116   G4bool first_section = true;
145   recalculatedEndPoint = false;                   117   recalculatedEndPoint = false; 
                                                   >> 118 
146   G4bool restoredFullEndpoint = false;            119   G4bool restoredFullEndpoint = false;
147                                                   120 
148   unsigned int substep_no = 0;                 << 121   G4int substep_no = 0;
149                                                   122 
150   // Statistics for substeps                   << 123   G4int oldprc;   // cout/cerr precision settings
151   static G4ThreadLocal unsigned int max_no_see << 
152                                                << 
153 #ifdef G4DEBUG_FIELD                           << 
154   unsigned int trigger_substepno_print = 0;    << 
155   const G4double tolerance = 1.0e-8 * CLHEP::m << 
156   unsigned int biggest_depth = 0;              << 
157     // using kInitialisingCL = G4LocatorChange << 
158 #endif                                         << 
159                                                   124 
160   // Log the location, iteration of changes in << 125   // Limits for substep number
161   //------------------------------------------ << 126   //
162   static G4ThreadLocal G4LocatorChangeLogger e << 127   const G4int max_substeps=   10000;  // Test 120  (old value 100 )
163     endChangeB("EndPointB"), recApproxPoint("A << 128   const G4int warn_substeps=   1000;  //      100  
164     pointH_logger("Trial points 'E': position, << 
165   unsigned int eventCount = 0;                 << 
166                                                   129 
167   if (fCheckMode)                              << 130   // Statistics for substeps
168   {                                            << 131   //
169     // Clear previous call's data              << 132   static G4int max_no_seen= -1; 
170     endChangeA.clear();                        << 133   static G4int trigger_substepno_print= warn_substeps - 20 ;
171     endChangeB.clear();                        << 
172     recApproxPoint.clear();                    << 
173     pointH_logger.clear();                     << 
174                                                << 
175     // Record the initialisation               << 
176     ++eventCount;                              << 
177     endChangeA.AddRecord( G4LocatorChangeRecor << 
178                           eventCount, CurrentA << 
179     endChangeB.AddRecord( G4LocatorChangeRecor << 
180                           eventCount, CurrentB << 
181   }                                            << 
182                                                   134 
183   //------------------------------------------    135   //--------------------------------------------------------------------------  
184   //  Algorithm for the case if progress in fo    136   //  Algorithm for the case if progress in founding intersection is too slow.
185   //  Process is defined too slow if after N=p    137   //  Process is defined too slow if after N=param_substeps advances on the
186   //  path, it will be only 'fraction_done' of    138   //  path, it will be only 'fraction_done' of the total length.
187   //  In this case the remaining length is div    139   //  In this case the remaining length is divided in two half and 
188   //  the loop is restarted for each half.        140   //  the loop is restarted for each half.  
189   //  If progress is still too slow, the divis    141   //  If progress is still too slow, the division in two halfs continue
190   //  until 'max_depth'.                          142   //  until 'max_depth'.
191   //------------------------------------------    143   //--------------------------------------------------------------------------
192                                                   144 
193   const G4int param_substeps = 5;  // Test val << 145   const G4int param_substeps=10; // Test value for the maximum number
194                                    // of subst << 146                                  // of substeps
195   const G4double fraction_done = 0.3;          << 147   const G4double fraction_done=0.3;
196                                                   148 
197   G4bool Second_half = false;    // First half    149   G4bool Second_half = false;    // First half or second half of divided step
198                                                   150 
199   // We need to know this for the 'final_secti    151   // We need to know this for the 'final_section':
200   // real 'final_section' or first half 'final    152   // real 'final_section' or first half 'final_section'
201   // In algorithm it is considered that the 'S    153   // In algorithm it is considered that the 'Second_half' is true
202   // and it becomes false only if we are in th    154   // and it becomes false only if we are in the first-half of level
203   // depthness or if we are in the first secti    155   // depthness or if we are in the first section
204                                                   156 
205   unsigned int depth = 0; // Depth counts subd << 157   G4int depth=0; // Depth counts how many subdivisions of initial step made
206   ++fNumCalls;                                 << 
207                                                << 
208   NormalAtEntry = GetSurfaceNormal(CurrentE_Po << 
209                                                   158 
210   if (fCheckMode)                              << 159 #ifdef G4DEBUG_FIELD
                                                   >> 160   static const G4double tolerance = 1.0e-8 * mm; 
                                                   >> 161   G4ThreeVector  StartPosition= CurveStartPointVelocity.GetPosition(); 
                                                   >> 162   if( (TrialPoint - StartPosition).mag() < tolerance) 
211   {                                               163   {
212     pointH_logger.AddRecord( G4LocatorChangeRe << 164      G4cerr << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
213                              substep_no, event << 165             << G4endl
214                              G4FieldTrack( Cur << 166             << "          Intermediate F point is on top of starting point A."
215                                            0., << 167             << G4endl;
216   #if (G4DEBUG_FIELD>1)                        << 168      G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()", 
217     G4ThreeVector  StartPosition = CurveStartP << 169                  "IntersectionPointIsAtStart", JustWarning,
218     if( (TrialPoint - StartPosition).mag2() <  << 170                  "Intersection point F is exactly at start point A." ); 
219     {                                          << 
220        ReportImmediateHit( MethodName, StartPo << 
221                            tolerance, fNumCall << 
222     }                                          << 
223   #endif                                       << 
224   }                                               171   }
                                                   >> 172 #endif
225                                                   173 
226   // Intermediates Points on the Track = Subdi    174   // Intermediates Points on the Track = Subdivided Points must be stored.
227   // Give the initial values to 'InterMedFt'      175   // Give the initial values to 'InterMedFt'
228   // Important is 'ptrInterMedFT[0]', it saves    176   // Important is 'ptrInterMedFT[0]', it saves the 'EndCurvePoint'
229   //                                              177   //
230   *ptrInterMedFT[0] = CurveEndPointVelocity;      178   *ptrInterMedFT[0] = CurveEndPointVelocity;
231   for ( auto idepth=1; idepth<max_depth+1; ++i << 179   for (G4int idepth=1; idepth<max_depth+1; idepth++ )
232   {                                               180   {
233     *ptrInterMedFT[idepth] = CurveStartPointVe << 181     *ptrInterMedFT[idepth]=CurveStartPointVelocity;
234   }                                               182   }
235                                                   183 
236   // Final_section boolean store                  184   // Final_section boolean store
237   //                                              185   //
238   G4bool fin_section_depth[max_depth];            186   G4bool fin_section_depth[max_depth];
239   for (bool & idepth : fin_section_depth)      << 187   for (G4int idepth=0; idepth<max_depth; idepth++ )
240   {                                               188   {
241     idepth = true;                             << 189     fin_section_depth[idepth]=true;
242   }                                               190   }
243   // 'SubStartPoint' is needed to calculate th    191   // 'SubStartPoint' is needed to calculate the length of the divided step
244   //                                              192   //
245   G4FieldTrack SubStart_PointVelocity = CurveS    193   G4FieldTrack SubStart_PointVelocity = CurveStartPointVelocity;
246                                                   194    
247   do  // Loop checking, 07.10.2016, J.Apostola << 195   do
248   {                                               196   {
249     unsigned int substep_no_p = 0;             << 197     G4int substep_no_p = 0;
250     G4bool sub_final_section = false; // the s    198     G4bool sub_final_section = false; // the same as final_section,
251                                       // but f    199                                       // but for 'sub_section'
252     SubStart_PointVelocity = CurrentA_PointVel << 200     SubStart_PointVelocity = CurrentA_PointVelocity; 
253                                                << 201     do // REPEAT param
254     do // Loop checking, 07.10.2016, J.Apostol << 202     {
255     { // REPEAT param                          << 
256       G4ThreeVector Point_A = CurrentA_PointVe    203       G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();  
257       G4ThreeVector Point_B = CurrentB_PointVe    204       G4ThreeVector Point_B = CurrentB_PointVelocity.GetPosition();
258                                                   205        
259 #ifdef G4DEBUG_FIELD                           << 
260       const G4double lenA = CurrentA_PointVelo << 
261       const G4double lenB = CurrentB_PointVelo << 
262       G4double curv_lenAB = lenB - lenA;       << 
263       G4double     distAB = (Point_B - Point_A << 
264       if( curv_lenAB < distAB * ( 1. - 10.*fiE << 
265       {                                        << 
266         G4cerr << "ERROR> (Start) Point A coin << 
267                << "MLL: iters = " << substep_n << 
268         G4long op=G4cerr.precision(6);         << 
269         G4cerr << "       Difference = " << di << 
270                << " exceeds limit of relative  << 
271                << "  i.e. limit = " << 10 * fi << 
272         G4cerr.precision(9);                   << 
273         G4cerr << "        Len A, B = " << len << 
274                << "        Position A: " << Po << 
275                << "        Position B: " << Po << 
276         G4cerr.precision(op);                  << 
277         // G4LocatorChangeRecord::ReportVector << 
278         // G4cerr<<"EndPoints A(start) and B(e << 
279         if (fCheckMode)                        << 
280         {                                      << 
281           G4LocatorChangeLogger::ReportEndChan << 
282         }                                      << 
283       }                                        << 
284                                                << 
285       if( !validIntersectP )                   << 
286       {                                        << 
287         G4ExceptionDescription errmsg;         << 
288         errmsg << "Assertion FAILURE - invalid << 
289                << substep_no << " call: " << f << 
290         if (fCheckMode)                        << 
291         {                                      << 
292           G4LocatorChangeRecord::ReportEndChan << 
293         }                                      << 
294         G4Exception("G4MultiLevelLocator::Esti << 
295                     JustWarning, errmsg);      << 
296       }                                        << 
297 #endif                                         << 
298                                                << 
299       // F = a point on true AB path close to     206       // F = a point on true AB path close to point E 
300       // (the closest if possible)                207       // (the closest if possible)
301       //                                          208       //
302       ApproxIntersecPointV = GetChordFinderFor    209       ApproxIntersecPointV = GetChordFinderFor()
303                              ->ApproxCurvePoin    210                              ->ApproxCurvePointV( CurrentA_PointVelocity, 
304                                                   211                                                   CurrentB_PointVelocity, 
305                                                   212                                                   CurrentE_Point,
306                                                << 213                                                   GetEpsilonStepFor());
307         // The above method is the key & most     214         // The above method is the key & most intuitive part ...
308                                                << 215      
309 #ifdef G4DEBUG_FIELD                           << 216 #ifdef G4DEBUG_FIELD
310       recApproxPoint.push_back(G4LocatorChange << 217       if( ApproxIntersecPointV.GetCurveLength() > 
311                                                << 218           CurrentB_PointVelocity.GetCurveLength() * (1.0 + tolerance) )
312       G4double lenIntsc= ApproxIntersecPointV. << 
313       G4double checkVsEnd= lenB - lenIntsc;    << 
314                                                << 
315       if( lenIntsc > lenB )                    << 
316       {                                           219       {
317         std::ostringstream errmsg;             << 220         G4cerr << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
318         errmsg.precision(17);                  << 221                << G4endl
319         G4double ratio    = checkVsEnd / lenB; << 222                << "        Intermediate F point is more advanced than"
320         G4double ratioTol = std::fabs(ratio) / << 223                << " endpoint B." << G4endl;
321         errmsg << "Intermediate F point is pas << 224         G4Exception("G4multiLevelLocator::EstimateIntersectionPoint()", 
322         << "   l( intersection ) = " << lenInt << 225                     "IntermediatePointConfusion", FatalException,
323         << "   l( endpoint     ) = " << lenB   << 226                     "Intermediate F point is past end B point" ); 
324         errmsg.precision(8);                   << 
325         errmsg << "   l_end - l_inters  = " << << 
326         << "          / l_end      = " << rati << 
327         << "   ratio  / tolerance  = " << rati << 
328         if( ratioTol < 1.0 )                   << 
329           G4Exception(MethodName, "GeomNav0003 << 
330         else                                   << 
331           G4Exception(MethodName, "GeomNav0003 << 
332       }                                           227       }
333 #endif                                            228 #endif
334                                                   229 
335       G4ThreeVector CurrentF_Point= ApproxInte    230       G4ThreeVector CurrentF_Point= ApproxIntersecPointV.GetPosition();
336                                                   231 
337       // First check whether EF is small - the    232       // First check whether EF is small - then F is a good approx. point 
338       // Calculate the length and direction of    233       // Calculate the length and direction of the chord AF
339       //                                          234       //
340       G4ThreeVector  ChordEF_Vector = CurrentF    235       G4ThreeVector  ChordEF_Vector = CurrentF_Point - CurrentE_Point;
341                                                   236 
342       G4ThreeVector  NewMomentumDir = ApproxIn << 237       if ( ChordEF_Vector.mag2() <= sqr(GetDeltaIntersectionFor()) )
343       G4double       MomDir_dot_Norm = NewMome << 
344                                                << 
345 #ifdef G4DEBUG_FIELD                           << 
346       if( fVerboseLevel > 3 )                  << 
347       {                                        << 
348          G4ThreeVector  ChordAB           = Po << 
349          G4double       ABchord_length    = Ch << 
350          G4double       MomDir_dot_ABchord;    << 
351          MomDir_dot_ABchord = (1.0 / ABchord_l << 
352                             * NewMomentumDir.d << 
353          G4VIntersectionLocator::ReportTrialSt << 
354               ChordEF_Vector, NewMomentumDir,  << 
355          G4cout << " dot( MomentumDir, ABchord << 
356                 << MomDir_dot_ABchord << G4end << 
357       }                                        << 
358 #endif                                         << 
359       G4bool adequate_angle =                  << 
360              ( MomDir_dot_Norm >= 0.0 ) // Can << 
361           || (! validNormalAtE );       // Inv << 
362       G4double EF_dist2 = ChordEF_Vector.mag2( << 
363       if ( ( EF_dist2 <= sqr(fiDeltaIntersecti << 
364         || ( EF_dist2 <= kCarTolerance*kCarTol << 
365       {                                           238       { 
366         found_approximate_intersection = true;    239         found_approximate_intersection = true;
367                                                   240 
368         // Create the "point" return value        241         // Create the "point" return value
369         //                                        242         //
370         IntersectedOrRecalculatedFT = ApproxIn    243         IntersectedOrRecalculatedFT = ApproxIntersecPointV;
371         IntersectedOrRecalculatedFT.SetPositio    244         IntersectedOrRecalculatedFT.SetPosition( CurrentE_Point );
372                                                   245 
373         if ( GetAdjustementOfFoundIntersection    246         if ( GetAdjustementOfFoundIntersection() )
374         {                                         247         {
375           // Try to Get Correction of Intersec    248           // Try to Get Correction of IntersectionPoint using SurfaceNormal()
376           //                                      249           //  
377           G4ThreeVector IP;                       250           G4ThreeVector IP;
378           G4ThreeVector MomentumDir=ApproxInte    251           G4ThreeVector MomentumDir=ApproxIntersecPointV.GetMomentumDirection();
379           G4bool goodCorrection = AdjustmentOf    252           G4bool goodCorrection = AdjustmentOfFoundIntersection(Point_A,
380                                     CurrentE_P    253                                     CurrentE_Point, CurrentF_Point, MomentumDir,
381                                     last_AF_in    254                                     last_AF_intersection, IP, NewSafety,
382                                     previousSa << 255                                     fPreviousSafety, fPreviousSftOrigin );
383           if ( goodCorrection )                   256           if ( goodCorrection )
384           {                                       257           {
385             IntersectedOrRecalculatedFT = Appr    258             IntersectedOrRecalculatedFT = ApproxIntersecPointV;
386             IntersectedOrRecalculatedFT.SetPos    259             IntersectedOrRecalculatedFT.SetPosition(IP);
387           }                                       260           }
388         }                                         261         }
389         // Note: in order to return a point on    262         // Note: in order to return a point on the boundary, 
390         //       we must return E. But it is F    263         //       we must return E. But it is F on the curve.
391         //       So we must "cheat": we are us    264         //       So we must "cheat": we are using the position at point E
392         //       and the velocity at point F !    265         //       and the velocity at point F !!!
393         //                                        266         //
394         // This must limit the length we can a    267         // This must limit the length we can allow for displacement!
395       }                                           268       }
396       else  // E is NOT close enough to the cu    269       else  // E is NOT close enough to the curve (ie point F)
397       {                                           270       {
398         // Check whether any volumes are encou    271         // Check whether any volumes are encountered by the chord AF
399         // -----------------------------------    272         // ---------------------------------------------------------
400         // First relocate to restore any Voxel    273         // First relocate to restore any Voxel etc information
401         // in the Navigator before calling Com    274         // in the Navigator before calling ComputeStep()
402         //                                        275         //
403         GetNavigatorFor()->LocateGlobalPointWi    276         GetNavigatorFor()->LocateGlobalPointWithinVolume( Point_A );
404                                                   277 
405         G4ThreeVector PointG;   // Candidate i    278         G4ThreeVector PointG;   // Candidate intersection point
406         G4double stepLengthAF;                    279         G4double stepLengthAF; 
407         G4bool Intersects_FB = false;          << 
408         G4bool Intersects_AF = IntersectChord(    280         G4bool Intersects_AF = IntersectChord( Point_A,   CurrentF_Point,
409                                                << 281                                                NewSafety,fPreviousSafety,
410                                                << 282                                                fPreviousSftOrigin,
411                                                   283                                                stepLengthAF,
412                                                   284                                                PointG );
413         last_AF_intersection = Intersects_AF;     285         last_AF_intersection = Intersects_AF;
414         if( Intersects_AF )                       286         if( Intersects_AF )
415         {                                         287         {
416           // G is our new Candidate for the in    288           // G is our new Candidate for the intersection point.
417           // It replaces  "E" and we will see  << 289           // It replaces  "E" and we will repeat the test to see if
418           CurrentB_PointVelocity = ApproxInter << 290           // it is a good enough approximate point for us.
419           CurrentE_Point = PointG;             << 291           //       B    <- F
420                                                << 292           //       E    <- G
421           validIntersectP = true;    // 'E' ha << 293           //
422                                                << 294           CurrentB_PointVelocity = ApproxIntersecPointV;
423           G4bool validNormalLast;              << 295           CurrentE_Point = PointG;  
424           NormalAtEntry  = GetSurfaceNormal( P << 
425           validNormalAtE = validNormalLast;    << 
426                                                   296 
427           // As we move point B, must take car << 297           // By moving point B, must take care if current
428           // AF has no intersection to try cur    298           // AF has no intersection to try current FB!!
429           fin_section_depth[depth] = false;    << 299           //
430                                                << 300           fin_section_depth[depth]=false;
431           if (fCheckMode)                      << 301           
432           {                                    << 302           
433             ++eventCount;                      << 
434             endChangeB.push_back(              << 
435               G4LocatorChangeRecord(G4LocatorC << 
436                              substep_no, event << 
437           }                                    << 
438 #ifdef G4VERBOSE                                  303 #ifdef G4VERBOSE
439           if( fVerboseLevel > 3 )                 304           if( fVerboseLevel > 3 )
440           {                                       305           {
441             G4cout << "G4PiF::LI> Investigatin    306             G4cout << "G4PiF::LI> Investigating intermediate point"
442                    << " at s=" << ApproxInters    307                    << " at s=" << ApproxIntersecPointV.GetCurveLength()
443                    << " on way to full s="        308                    << " on way to full s="
444                    << CurveEndPointVelocity.Ge    309                    << CurveEndPointVelocity.GetCurveLength() << G4endl;
445           }                                       310           }
446 #endif                                            311 #endif
447         }                                         312         }
448         else  // not Intersects_AF                313         else  // not Intersects_AF
449         {                                         314         {  
450           // In this case:                        315           // In this case:
451           // There is NO intersection of AF wi    316           // There is NO intersection of AF with a volume boundary.
452           // We must continue the search in th    317           // We must continue the search in the segment FB!
453           //                                      318           //
454           GetNavigatorFor()->LocateGlobalPoint    319           GetNavigatorFor()->LocateGlobalPointWithinVolume( CurrentF_Point );
455                                                   320 
456           G4double stepLengthFB;                  321           G4double stepLengthFB;
457           G4ThreeVector PointH;                   322           G4ThreeVector PointH;
458                                                   323 
459           // Check whether any volumes are enc    324           // Check whether any volumes are encountered by the chord FB
460           // ---------------------------------    325           // ---------------------------------------------------------
461                                                   326 
462           Intersects_FB = IntersectChord( Curr << 327           G4bool Intersects_FB = IntersectChord( CurrentF_Point, Point_B, 
463                                           NewS << 328                                                  NewSafety,fPreviousSafety,
464                                           prev << 329                                                  fPreviousSftOrigin,
465                                           step << 330                                                  stepLengthFB,
466                                           Poin << 331                                                  PointH );
467           if( Intersects_FB )                     332           if( Intersects_FB )
468           {                                       333           {
469             // There is an intersection of FB     334             // There is an intersection of FB with a volume boundary
470             // H <- First Intersection of Chor    335             // H <- First Intersection of Chord FB 
471                                                   336 
472             // H is our new Candidate for the     337             // H is our new Candidate for the intersection point.
473             // It replaces  "E" and we will re    338             // It replaces  "E" and we will repeat the test to see if
474             // it is a good enough approximate    339             // it is a good enough approximate point for us.
475                                                   340 
476             // Note that F must be in volume v    341             // Note that F must be in volume volA  (the same as A)
477             // (otherwise AF would meet a volu    342             // (otherwise AF would meet a volume boundary!)
478             //   A    <- F                        343             //   A    <- F 
479             //   E    <- H                        344             //   E    <- H
480             //                                    345             //
481             CurrentA_PointVelocity = ApproxInt    346             CurrentA_PointVelocity = ApproxIntersecPointV;
482             CurrentE_Point = PointH;              347             CurrentE_Point = PointH;
483                                                << 
484             validIntersectP = true;    // 'E'  << 
485                                                << 
486             G4bool validNormalH;               << 
487             NormalAtEntry  = GetSurfaceNormal( << 
488             validNormalAtE = validNormalH;     << 
489                                                << 
490             if (fCheckMode)                    << 
491             {                                  << 
492               ++eventCount;                    << 
493               endChangeA.push_back(            << 
494                  G4LocatorChangeRecord(G4Locat << 
495                              substep_no, event << 
496               G4FieldTrack intersectH_pn('0'); << 
497                                                << 
498               intersectH_pn.SetPosition( Point << 
499               intersectH_pn.SetMomentum( Norma << 
500               pointH_logger.AddRecord(G4Locato << 
501                                     substep_no << 
502             }                                  << 
503           }                                       348           }
504           else  // not Intersects_FB              349           else  // not Intersects_FB
505           {                                       350           {
506             validIntersectP = false;    // Int << 351             // There is NO intersection of FB with a volume boundary
507             if( fin_section_depth[depth] )     << 352 
                                                   >> 353             if(fin_section_depth[depth])
508             {                                     354             {
509               // If B is the original endpoint    355               // If B is the original endpoint, this means that whatever
510               // volume(s) intersected the ori    356               // volume(s) intersected the original chord, none touch the
511               // smaller chords we have used.     357               // smaller chords we have used.
512               // The value of 'IntersectedOrRe    358               // The value of 'IntersectedOrRecalculatedFT' returned is
513               // likely not valid                 359               // likely not valid 
514                                                   360 
515               // Check on real final_section o    361               // Check on real final_section or SubEndSection
516               //                                  362               //
517               if( ((Second_half)&&(depth==0))     363               if( ((Second_half)&&(depth==0)) || (first_section) )
518               {                                   364               {
519                 there_is_no_intersection = tru    365                 there_is_no_intersection = true;   // real final_section
520               }                                   366               }
521               else                                367               else
522               {                                   368               {
523                 // end of subsection, not real    369                 // end of subsection, not real final section 
524                 // exit from the and go to the    370                 // exit from the and go to the depth-1 level 
                                                   >> 371 
525                 substep_no_p = param_substeps+    372                 substep_no_p = param_substeps+2;  // exit from the loop
526                                                   373 
527                 // but 'Second_half' is still     374                 // but 'Second_half' is still true because we need to find
528                 // the 'CurrentE_point' for th    375                 // the 'CurrentE_point' for the next loop
                                                   >> 376                 //
529                 Second_half = true;               377                 Second_half = true; 
530                 sub_final_section = true;         378                 sub_final_section = true;
                                                   >> 379                 
531               }                                   380               }
532             }                                     381             }
533             else                                  382             else
534             {                                     383             {
535               CurrentA_PointVelocity = Current << 384               if(depth==0)
536               CurrentB_PointVelocity = (depth= << 385               {
537                                                << 386                 // We must restore the original endpoint
538               SubStart_PointVelocity = Current << 387                 //
539               restoredFullEndpoint = true;     << 388                 CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
540                                                << 389                 CurrentB_PointVelocity = CurveEndPointVelocity;
541               validIntersectP = false;  // 'E' << 390                 SubStart_PointVelocity = CurrentA_PointVelocity;
542                                                << 391                 restoredFullEndpoint = true;
543               if (fCheckMode)                  << 392               }
                                                   >> 393               else
544               {                                   394               {
545                 ++eventCount;                  << 395                 // We must restore the depth endpoint
546                 endChangeA.push_back(          << 396                 //
547                   G4LocatorChangeRecord(       << 397                 CurrentA_PointVelocity = CurrentB_PointVelocity;  // Got to B
548                     G4LocatorChangeRecord::kNo << 398                 CurrentB_PointVelocity =  *ptrInterMedFT[depth];
549                              substep_no, event << 399                 SubStart_PointVelocity = CurrentA_PointVelocity;
550                 endChangeB.push_back(          << 400                 restoredFullEndpoint = true;
551                   G4LocatorChangeRecord (      << 
552                     G4LocatorChangeRecord::kNo << 
553                              substep_no, event << 
554               }                                   401               }
555             }                                     402             }
556           } // Endif (Intersects_FB)              403           } // Endif (Intersects_FB)
557         } // Endif (Intersects_AF)                404         } // Endif (Intersects_AF)
558                                                   405 
559         G4int errorEndPt = 0; // Default: no e << 406         // Ensure that the new endpoints are not further apart in space
                                                   >> 407         // than on the curve due to different errors in the integration
                                                   >> 408         //
                                                   >> 409         G4double linDistSq, curveDist; 
                                                   >> 410         linDistSq = ( CurrentB_PointVelocity.GetPosition() 
                                                   >> 411                     - CurrentA_PointVelocity.GetPosition() ).mag2(); 
                                                   >> 412         curveDist = CurrentB_PointVelocity.GetCurveLength()
                                                   >> 413                     - CurrentA_PointVelocity.GetCurveLength();
560                                                   414 
561         G4bool recalculatedB= false;           << 415         // Change this condition for very strict parameters of propagation 
562         if( driverReIntegrates )               << 416         //
563         {                                      << 417         if( curveDist*curveDist*(1+2* GetEpsilonStepFor()) < linDistSq )
564           G4FieldTrack RevisedB_FT = CurrentB_ << 418         {  
565           recalculatedB= CheckAndReEstimateEnd << 419           // Re-integrate to obtain a new B
566                                                << 420           //
567                                                << 421           G4FieldTrack newEndPointFT=
568                                                << 422                   ReEstimateEndpoint( CurrentA_PointVelocity,
569           if( recalculatedB )                  << 423                                       CurrentB_PointVelocity,
                                                   >> 424                                       linDistSq,    // to avoid recalculation
                                                   >> 425                                       curveDist );
                                                   >> 426           G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
                                                   >> 427           CurrentB_PointVelocity = newEndPointFT;
                                                   >> 428            
                                                   >> 429           if ( (fin_section_depth[depth])           // real final section
                                                   >> 430              &&( first_section || ((Second_half)&&(depth==0)) ) )
570           {                                       431           {
571             CurrentB_PointVelocity = RevisedB_ << 432             recalculatedEndPoint = true;
572             // Do not invalidate intersection  << 433             IntersectedOrRecalculatedFT = newEndPointFT;
573             //                                 << 
574             // The best course would be to inv << 
575             // BUT if we invalidate it, we mus << 
576             //   validIntersectP = false;  //  << 
577                                                << 
578             if ( (fin_section_depth[depth])    << 
579                &&( first_section || ((Second_h << 
580             {                                  << 
581               recalculatedEndPoint = true;     << 
582               IntersectedOrRecalculatedFT = Re << 
583               // So that we can return it, if     434               // So that we can return it, if it is the endpoint!
584             }                                  << 
585             // else                            << 
586             //  Move forward the other points  << 
587             //   - or better flag it, so that  << 
588             //     [ Implementation: a counter << 
589             //       => avoids extra work]     << 
590           }                                    << 
591           if (fCheckMode)                      << 
592           {                                    << 
593             ++eventCount;                      << 
594             endChangeB.push_back(              << 
595               G4LocatorChangeRecord( G4Locator << 
596                                      substep_n << 
597           }                                       435           }
598         }                                         436         }
599         else                                   << 437         if( curveDist < 0.0 )
600         {                                         438         {
601           if( CurrentB_PointVelocity.GetCurveL << 439           G4cerr << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
602             < CurrentA_PointVelocity.GetCurveL << 440                  << G4endl
603           {                                    << 441                  << "        Error in advancing propagation." << G4endl;
604             errorEndPt = 2;                    << 442           fVerboseLevel = 5; // Print out a maximum of information
605           }                                    << 443           printStatus( CurrentA_PointVelocity,  CurrentB_PointVelocity,
                                                   >> 444                        -1.0, NewSafety,  substep_no );
                                                   >> 445           G4cerr << "        Point A (start) is " << CurrentA_PointVelocity
                                                   >> 446                  << G4endl;
                                                   >> 447           G4cerr << "        Point B (end)   is " << CurrentB_PointVelocity
                                                   >> 448                  << G4endl;
                                                   >> 449           G4cerr << "        Curve distance is " << curveDist << G4endl;
                                                   >> 450           G4cerr << G4endl
                                                   >> 451                  << "The final curve point is not further along"
                                                   >> 452                  << " than the original!" << G4endl;
                                                   >> 453 
                                                   >> 454           if( recalculatedEndPoint )
                                                   >> 455           {
                                                   >> 456             G4cerr << "Recalculation of EndPoint was called with fEpsStep= "
                                                   >> 457                    << GetEpsilonStepFor() << G4endl;
                                                   >> 458           }
                                                   >> 459           oldprc = G4cerr.precision(20);
                                                   >> 460           G4cerr << " Point A (Curve start)   is " << CurveStartPointVelocity
                                                   >> 461                  << G4endl;
                                                   >> 462           G4cerr << " Point B (Curve   end)   is " << CurveEndPointVelocity
                                                   >> 463                  << G4endl;
                                                   >> 464           G4cerr << " Point A (Current start) is " << CurrentA_PointVelocity
                                                   >> 465                  << G4endl;
                                                   >> 466           G4cerr << " Point B (Current end)   is " << CurrentB_PointVelocity
                                                   >> 467                  << G4endl;
                                                   >> 468           G4cerr << " Point S (Sub start)     is " << SubStart_PointVelocity
                                                   >> 469                  << G4endl;
                                                   >> 470           G4cerr << " Point E (Trial Point)   is " << CurrentE_Point
                                                   >> 471                  << G4endl;
                                                   >> 472           G4cerr << " Point F (Intersection)  is " << ApproxIntersecPointV
                                                   >> 473                  << G4endl;
                                                   >> 474           G4cerr << "        LocateIntersection parameters are : Substep no= "
                                                   >> 475                  << substep_no << G4endl;
                                                   >> 476           G4cerr << "        Substep depth no= "<< substep_no_p  << " Depth= "
                                                   >> 477                  << depth << G4endl;
                                                   >> 478           G4cerr.precision(oldprc);
                                                   >> 479 
                                                   >> 480           G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
                                                   >> 481                       "FatalError", FatalException,
                                                   >> 482                       "Error in advancing propagation.");
606         }                                         483         }
607                                                << 484         if(restoredFullEndpoint)
608         if( errorEndPt > 1 )  // errorEndPt =  << 
609         {                                      << 
610           std::ostringstream errmsg;           << 
611                                                << 
612           ReportReversedPoints(errmsg,         << 
613                                CurveStartPoint << 
614                                NewSafety, fiEp << 
615                                CurrentA_PointV << 
616                                SubStart_PointV << 
617                                ApproxIntersecP << 
618                                                << 
619           if (fCheckMode)                      << 
620           {                                    << 
621             G4LocatorChangeRecord::ReportEndCh << 
622           }                                    << 
623                                                << 
624           errmsg << G4endl << " * Location: "  << 
625                  << "- After EndIf(Intersects_ << 
626           errmsg << " * Bool flags:  Recalcula << 
627                  << "   Intersects_AF = " << I << 
628                  << "   Intersects_FB = " << I << 
629           errmsg << " * Number of calls to MLL << 
630           G4Exception(MethodName, "GeomNav0003 << 
631         }                                      << 
632         if( restoredFullEndpoint )             << 
633         {                                         485         {
634           fin_section_depth[depth] = restoredF    486           fin_section_depth[depth] = restoredFullEndpoint;
635           restoredFullEndpoint = false;           487           restoredFullEndpoint = false;
636         }                                         488         }
637       } // EndIf ( E is close enough to the cu    489       } // EndIf ( E is close enough to the curve, ie point F. )
638         // tests ChordAF_Vector.mag() <= maxim    490         // tests ChordAF_Vector.mag() <= maximum_lateral_displacement 
639                                                   491 
640 #ifdef G4DEBUG_FIELD                           << 492 #ifdef G4DEBUG_LOCATE_INTERSECTION  
641       if( trigger_substepno_print == 0)        << 
642       {                                        << 
643         trigger_substepno_print= fWarnSteps -  << 
644       }                                        << 
645                                                << 
646       if( substep_no >= trigger_substepno_prin    493       if( substep_no >= trigger_substepno_print )
647       {                                           494       {
648         G4cout << "Difficulty in converging in << 495         G4cout << "Difficulty in converging in "
                                                   >> 496                << "G4MultiLevelLocator::EstimateIntersectionPoint():"
                                                   >> 497                << G4endl
649                << "    Substep no = " << subst    498                << "    Substep no = " << substep_no << G4endl;
650         if( substep_no == trigger_substepno_pr    499         if( substep_no == trigger_substepno_print )
651         {                                         500         {
652           G4cout << " Start:   ";              << 
653           printStatus( CurveStartPointVelocity    501           printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
654                        -1.0, NewSafety, 0 );   << 502                        -1.0, NewSafety, 0);
655           if( fCheckMode ) {                   << 
656             G4LocatorChangeRecord::ReportEndCh << 
657           } else {                             << 
658             G4cout << " ** For more informatio << 
659                    << "-- (it saves and can ou << 
660           }                                    << 
661         }                                         503         }
662         G4cout << " Point A: ";                << 504         G4cout << " State of point A: "; 
663         printStatus( CurrentA_PointVelocity, C    505         printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
664                      -1.0, NewSafety, substep_ << 506                      -1.0, NewSafety, substep_no-1, 0);
665         G4cout << " Point B: ";                << 507         G4cout << " State of point B: "; 
666         printStatus( CurrentA_PointVelocity, C    508         printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
667                      -1.0, NewSafety, substep_ << 509                      -1.0, NewSafety, substep_no);
668       }                                           510       }
669 #endif                                            511 #endif
670       ++substep_no;                            << 512       substep_no++; 
671       ++substep_no_p;                          << 513       substep_no_p++;
672                                                   514 
673     } while (  ( ! found_approximate_intersect    515     } while (  ( ! found_approximate_intersection )
674             && ( ! there_is_no_intersection )     516             && ( ! there_is_no_intersection )     
675             && validIntersectP        // New c << 
676             && ( substep_no_p <= param_substep    517             && ( substep_no_p <= param_substeps) );  // UNTIL found or
677                                                   518                                                      // failed param substep
                                                   >> 519     first_section = false;
678                                                   520 
679     if( (!found_approximate_intersection) && (    521     if( (!found_approximate_intersection) && (!there_is_no_intersection) )
680     {                                             522     {
681       G4double did_len = std::abs( CurrentA_Po    523       G4double did_len = std::abs( CurrentA_PointVelocity.GetCurveLength()
682                        - SubStart_PointVelocit    524                        - SubStart_PointVelocity.GetCurveLength()); 
683       G4double all_len = std::abs( CurrentB_Po    525       G4double all_len = std::abs( CurrentB_PointVelocity.GetCurveLength()
684                        - SubStart_PointVelocit    526                        - SubStart_PointVelocity.GetCurveLength());
685                                                   527    
686       G4double distAB = -1;                    << 528       G4double stepLengthAB;
                                                   >> 529       G4ThreeVector PointGe;
                                                   >> 530       // Check if progress is too slow and if it possible to go deeper,
                                                   >> 531       // then halve the step if so
687       //                                          532       //
688       // Is progress is too slow, and is it po << 533       if( ( ( did_len )<fraction_done*all_len)
689       // If so, then *halve the step*          << 
690       //              ==============           << 
691       if(   (did_len < fraction_done*all_len)  << 
692          && (depth<max_depth) && (!sub_final_s    534          && (depth<max_depth) && (!sub_final_section) )
693       {                                           535       {
694 #ifdef G4DEBUG_FIELD                           << 536         Second_half=false;
695         static G4ThreadLocal unsigned int numS << 537         depth++;
696         biggest_depth = std::max(depth, bigges << 
697         ++numSplits;                           << 
698 #endif                                         << 
699         Second_half = false;                   << 
700         ++depth;                               << 
701         first_section = false;                 << 
702                                                   538 
703         G4double Sub_len = (all_len-did_len)/(    539         G4double Sub_len = (all_len-did_len)/(2.);
704         G4FieldTrack midPoint = CurrentA_Point << 540         G4FieldTrack start = CurrentA_PointVelocity;
705         G4bool fullAdvance=                    << 541         G4MagInt_Driver* integrDriver
706            integrDriver->AccurateAdvance(midPo << 542                          = GetChordFinderFor()->GetIntegrationDriver();
707                                                << 543         integrDriver->AccurateAdvance(start, Sub_len, GetEpsilonStepFor());
708         ++fNumAdvanceTrials;                   << 544         *ptrInterMedFT[depth] = start;
709         if( fullAdvance )  { ++fNumAdvanceFull << 545         CurrentB_PointVelocity = *ptrInterMedFT[depth];
710                                                << 546  
711         G4double lenAchieved=                  << 
712            midPoint.GetCurveLength()-CurrentA_ << 
713                                                << 
714         const G4double adequateFraction = (1.0 << 
715         G4bool goodAdvance = (lenAchieved >= a << 
716         if ( goodAdvance )  { ++fNumAdvanceGoo << 
717                                                << 
718 #ifdef G4DEBUG_FIELD                           << 
719         else  //  !goodAdvance                 << 
720         {                                      << 
721            G4cout << "MLL> AdvanceChordLimited << 
722                   << "  total length achieved  << 
723                   << Sub_len << "  fraction= " << 
724            if (Sub_len != 0.0 ) { G4cout << le << 
725            else                 { G4cout << "D << 
726            G4cout << "  Good-enough fraction = << 
727            G4cout << "  Number of call to mll  << 
728                   << "   iteration " << subste << 
729                   << "  inner =  " << substep_ << 
730            G4cout << "  Epsilon of integration << 
731            G4cout << "  State at start is      << 
732                   << G4endl                    << 
733                   << "        at end (midpoint << 
734            G4cout << "  Particle mass = " << m << 
735                                                << 
736            G4EquationOfMotion *equation = inte << 
737            ReportFieldValue( CurrentA_PointVel << 
738            ReportFieldValue( midPoint, "midPoi << 
739            G4cout << "  Original Start = "     << 
740                   << CurveStartPointVelocity < << 
741            G4cout << "  Original   End = "     << 
742                   << CurveEndPointVelocity <<  << 
743            G4cout << "  Original TrialPoint =  << 
744                   << TrialPoint << G4endl;     << 
745            G4cout << "  (this is STRICT mode)  << 
746                   << "  num Splits= " << numSp << 
747            G4cout << G4endl;                   << 
748         }                                      << 
749 #endif                                         << 
750                                                << 
751         *ptrInterMedFT[depth] =  midPoint;     << 
752         CurrentB_PointVelocity = midPoint;     << 
753                                                << 
754         if (fCheckMode)                        << 
755         {                                      << 
756           ++eventCount;                        << 
757           endChangeB.push_back(                << 
758             G4LocatorChangeRecord( G4LocatorCh << 
759                                    substep_no, << 
760         }                                      << 
761                                                << 
762         // Adjust 'SubStartPoint' to calculate    547         // Adjust 'SubStartPoint' to calculate the 'did_length' in next loop
763         //                                        548         //
764         SubStart_PointVelocity = CurrentA_Poin    549         SubStart_PointVelocity = CurrentA_PointVelocity;
765                                                   550 
766         // Find new trial intersection point n    551         // Find new trial intersection point needed at start of the loop
767         //                                        552         //
768         G4ThreeVector Point_A = CurrentA_Point    553         G4ThreeVector Point_A = CurrentA_PointVelocity.GetPosition();
769         G4ThreeVector Point_B = CurrentB_Point << 554         G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
770                                                << 555      
771         G4ThreeVector PointGe;                 << 
772         GetNavigatorFor()->LocateGlobalPointWi    556         GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
773         G4bool Intersects_AB = IntersectChord( << 557         G4bool Intersects_AB = IntersectChord(Point_A, SubE_point,
774                                                << 558                                               NewSafety, fPreviousSafety,
775                                                << 559                                               fPreviousSftOrigin,stepLengthAB,
776                                                   560                                               PointGe);
777         if( Intersects_AB )                       561         if( Intersects_AB )
778         {                                         562         {
779           last_AF_intersection = Intersects_AB    563           last_AF_intersection = Intersects_AB;
780           CurrentE_Point = PointGe;               564           CurrentE_Point = PointGe;
781           fin_section_depth[depth] = true;     << 565           fin_section_depth[depth]=true;
782                                                << 
783           validIntersectP = true;  // 'E' has  << 
784                                                << 
785           G4bool validNormalAB;                << 
786           NormalAtEntry  = GetSurfaceNormal( P << 
787           validNormalAtE = validNormalAB;      << 
788         }                                         566         }
789         else                                      567         else
790         {                                         568         {
791           // No intersection found for first p    569           // No intersection found for first part of curve
792           // (CurrentA,InterMedPoint[depth]).     570           // (CurrentA,InterMedPoint[depth]). Go to the second part
793           //                                      571           //
794           Second_half = true;                     572           Second_half = true;
795                                                << 
796           validIntersectP=  false;  // No new  << 
797         }                                         573         }
798       } // if did_len                             574       } // if did_len
799                                                   575 
800       G4bool unfinished = Second_half;         << 576       if( (Second_half)&&(depth!=0) )
801       while ( unfinished && (depth>0) )  // Lo << 
802       {                                           577       {
803         // Second part of curve (InterMed[dept << 578         // Second part of curve (InterMed[depth],Intermed[depth-1])                       ) 
804         // On the depth-1 level normally we ar    579         // On the depth-1 level normally we are on the 'second_half'
805                                                   580 
                                                   >> 581         Second_half = true;
806         //  Find new trial intersection point     582         //  Find new trial intersection point needed at start of the loop
807         //                                        583         //
808         SubStart_PointVelocity = *ptrInterMedF    584         SubStart_PointVelocity = *ptrInterMedFT[depth];
809         CurrentA_PointVelocity = *ptrInterMedF    585         CurrentA_PointVelocity = *ptrInterMedFT[depth];
810         CurrentB_PointVelocity = *ptrInterMedF    586         CurrentB_PointVelocity = *ptrInterMedFT[depth-1];
811                                                << 587          // Ensure that the new endpoints are not further apart in space
812         if (fCheckMode)                        << 
813         {                                      << 
814           ++eventCount;                        << 
815           G4LocatorChangeRecord chngPop_a( G4L << 
816                               substep_no, even << 
817           endChangeA.push_back( chngPop_a );   << 
818           G4LocatorChangeRecord chngPop_b( G4L << 
819                               substep_no, even << 
820           endChangeB.push_back( chngPop_b );   << 
821         }                                      << 
822                                                << 
823         // Ensure that the new endpoints are n << 
824         // than on the curve due to different     588         // than on the curve due to different errors in the integration
825         //                                        589         //
826         G4int  errorEndPt = -1;                << 590         G4double linDistSq, curveDist; 
827         G4bool recalculatedB= false;           << 591         linDistSq = ( CurrentB_PointVelocity.GetPosition() 
828         if( driverReIntegrates )               << 592                     - CurrentA_PointVelocity.GetPosition() ).mag2(); 
                                                   >> 593         curveDist = CurrentB_PointVelocity.GetCurveLength()
                                                   >> 594                     - CurrentA_PointVelocity.GetCurveLength();
                                                   >> 595         if( curveDist*curveDist*(1+2*GetEpsilonStepFor() ) < linDistSq )
829         {                                         596         {
830           // Ensure that the new endpoints are << 597           // Re-integrate to obtain a new B
831           // than on the curve due to differen << 
832           //                                      598           //
833           G4FieldTrack RevisedEndPointFT = Cur << 599           G4FieldTrack newEndPointFT=
834           recalculatedB =                      << 600                   ReEstimateEndpoint( CurrentA_PointVelocity,
835              CheckAndReEstimateEndpoint( Curre << 601                                       CurrentB_PointVelocity,
836                                          Curre << 602                                       linDistSq,    // to avoid recalculation
837                                          Revis << 603                                       curveDist );
838                                          error << 604           G4FieldTrack oldPointVelB = CurrentB_PointVelocity; 
839           if( recalculatedB )                  << 605           CurrentB_PointVelocity = newEndPointFT;
840           {                                    << 606           if (depth==1)
841             CurrentB_PointVelocity = RevisedEn << 607           {
842                                                << 608             recalculatedEndPoint = true;
843             if ( depth == 1 )                  << 609             IntersectedOrRecalculatedFT = newEndPointFT;
844             {                                  << 610             // So that we can return it, if it is the endpoint!
845                recalculatedEndPoint = true;    << 
846                IntersectedOrRecalculatedFT = R << 
847                // So that we can return it, if << 
848             }                                  << 
849           }                                       611           }
850           else                                 << 
851           {                                    << 
852             if( CurrentB_PointVelocity.GetCurv << 
853               < CurrentA_PointVelocity.GetCurv << 
854             {                                  << 
855               errorEndPt = 2;                  << 
856             }                                  << 
857           }                                    << 
858                                                << 
859           if (fCheckMode)                      << 
860           {                                    << 
861             ++eventCount;                      << 
862             endChangeB.push_back(              << 
863               G4LocatorChangeRecord(G4LocatorC << 
864                                     substep_no << 
865           }                                    << 
866         }                                      << 
867         if( errorEndPt > 1 )  // errorEndPt =  << 
868         {                                      << 
869           std::ostringstream errmsg;           << 
870           ReportReversedPoints(errmsg,         << 
871                     CurveStartPointVelocity, C << 
872                     NewSafety, fiEpsilonStep,  << 
873                     CurrentA_PointVelocity, Cu << 
874                     SubStart_PointVelocity, Cu << 
875                     ApproxIntersecPointV, subs << 
876           errmsg << " * Location:  " << Method << 
877           errmsg << " * Recalculated = " << re << 
878           G4Exception(MethodName, "GeomNav0003 << 
879         }                                         612         }
880                                                << 613 
881         G4ThreeVector Point_A = CurrentA_Point << 614         G4ThreeVector Point_A    = CurrentA_PointVelocity.GetPosition();
882         G4ThreeVector Point_B = CurrentB_Point << 615         G4ThreeVector SubE_point = CurrentB_PointVelocity.GetPosition();   
883         G4ThreeVector PointGi;                 << 
884         GetNavigatorFor()->LocateGlobalPointWi    616         GetNavigatorFor()->LocateGlobalPointWithinVolume(Point_A);
885         G4bool Intersects_AB = IntersectChord( << 617         G4bool Intersects_AB = IntersectChord(Point_A, SubE_point, NewSafety,
886                                                << 618                                               fPreviousSafety,
887                                                << 619                                               fPreviousSftOrigin,stepLengthAB,
888                                                << 620                                               PointGe);
889         if( Intersects_AB )                       621         if( Intersects_AB )
890         {                                         622         {
891           last_AF_intersection = Intersects_AB    623           last_AF_intersection = Intersects_AB;
892           CurrentE_Point = PointGi;            << 624           CurrentE_Point = PointGe;
893                                                << 625         }       
894           validIntersectP = true;  // 'E' has  << 
895           NormalAtEntry  = GetSurfaceNormal( P << 
896         }                                      << 
897         else                                   << 
898         {                                      << 
899           validIntersectP = false;  // No new  << 
900           if( depth == 1)                      << 
901           {                                    << 
902             there_is_no_intersection = true;   << 
903           }                                    << 
904         }                                      << 
905         depth--;                                  626         depth--;
906         fin_section_depth[depth] = true;       << 627         fin_section_depth[depth]=true;
907         unfinished = !validIntersectP;         << 
908       }                                        << 
909 #ifdef G4DEBUG_FIELD                           << 
910       if( ! ( validIntersectP || there_is_no_i << 
911       {                                        << 
912          // What happened ??                   << 
913          G4cout << "MLL - WARNING Potential FA << 
914                 << G4endl                      << 
915                 << " Depth = " << depth << G4e << 
916                 << " Num Substeps= " << subste << 
917          G4cout << " Found intersection= " <<  << 
918                 << G4endl;                     << 
919          G4cout << " Progress report: -- " <<  << 
920          ReportProgress(G4cout,                << 
921                         CurveStartPointVelocit << 
922                         substep_no, CurrentA_P << 
923                         CurrentB_PointVelocity << 
924                         NewSafety, depth );    << 
925          G4cout << G4endl;                     << 
926       }                                           628       }
927 #endif                                         << 
928     }  // if(!found_aproximate_intersection)      629     }  // if(!found_aproximate_intersection)
929                                                   630 
930     assert( validIntersectP || there_is_no_int << 
931                             || found_approxima << 
932                                                << 
933   } while ( ( ! found_approximate_intersection    631   } while ( ( ! found_approximate_intersection )
934             && ( ! there_is_no_intersection )     632             && ( ! there_is_no_intersection )     
935             && ( substep_no <= fMaxSteps) ); / << 633             && ( substep_no <= max_substeps) ); // UNTIL found or failed
936                                                   634 
937   if( substep_no > max_no_seen )                  635   if( substep_no > max_no_seen )
938   {                                               636   {
939     max_no_seen = substep_no;                     637     max_no_seen = substep_no; 
940 #ifdef G4DEBUG_FIELD                           << 638     if( max_no_seen > warn_substeps )
941     if( max_no_seen > fWarnSteps )             << 
942     {                                             639     {
943       trigger_substepno_print = max_no_seen-20    640       trigger_substepno_print = max_no_seen-20; // Want to see last 20 steps 
944     }                                             641     } 
945 #endif                                         << 
946   }                                               642   }
947                                                   643 
948   if( !there_is_no_intersection && !found_appr << 644   if(  ( substep_no >= max_substeps)
                                                   >> 645       && !there_is_no_intersection
                                                   >> 646       && !found_approximate_intersection )
949   {                                               647   {
950      if( substep_no >= fMaxSteps)              << 648     G4cerr << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
951      {                                         << 649            << G4endl
952         // Since we cannot go further (yet), w << 650            << "          Convergence is requiring too many substeps: "
953                                                << 651            << substep_no << G4endl;
954         recalculatedEndPoint = true;           << 652     G4cerr << "          Abandoning effort to intersect. " << G4endl;
955         IntersectedOrRecalculatedFT = CurrentA << 653     G4cerr << "          Information on start & current step follows in cout."
956         found_approximate_intersection = false << 654            << G4endl;
957                                                << 655     G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
958         std::ostringstream message;            << 656            << G4endl
959         message << G4endl;                     << 657            << "          Convergence is requiring too many substeps: "
960         message << "Convergence is requiring t << 658            << substep_no << G4endl;
961                 << substep_no << "  ( limit =  << 659     G4cout << "          Found intersection = "
962                 << G4endl                      << 660            << found_approximate_intersection << G4endl
963                 << "  Abandoning effort to int << 661            << "          Intersection exists = "
964         message << "    Number of calls to MLL << 662            << !there_is_no_intersection << G4endl;
965         message << "  iteration = " << substep << 663     G4cout << "          Start and Endpoint of Requested Step:" << G4endl;
966                                                << 664     printStatus( CurveStartPointVelocity, CurveEndPointVelocity,
967         message.precision( 12 );               << 665                  -1.0, NewSafety, 0);
968         G4double done_len = CurrentA_PointVelo << 666     G4cout << G4endl;
969         G4double full_len = CurveEndPointVeloc << 667     G4cout << "          'Bracketing' starting and endpoint of current Sub-Step"
970         message << "        Undertaken only le << 668            << G4endl;
971                 << " out of " << full_len << " << 669     printStatus( CurrentA_PointVelocity, CurrentA_PointVelocity,
972                 << "        Remaining length = << 670                  -1.0, NewSafety, substep_no-1);
973                                                << 671     printStatus( CurrentA_PointVelocity, CurrentB_PointVelocity,
974         message << "     Start and end-point o << 672                  -1.0, NewSafety, substep_no);
975         printStatus( CurveStartPointVelocity,  << 673     G4cout << G4endl;
976                      -1.0, NewSafety, 0,     m << 674  
977         message << "        Start and end-poin << 675 #ifdef FUTURE_CORRECTION
978         printStatus( CurrentA_PointVelocity, C << 676     // Attempt to correct the results of the method // FIX - TODO
979                      -1.0, NewSafety, substep_ << 
980         printStatus( CurrentA_PointVelocity, C << 
981                      -1.0, NewSafety, substep_ << 
982                                                << 
983         G4Exception(MethodName, "GeomNav0003", << 
984      }                                         << 
985      else if( substep_no >= fWarnSteps)        << 
986      {                                         << 
987         std::ostringstream message;            << 
988         message << "Many substeps while trying << 
989                 << G4endl                      << 
990                 << "          Undertaken lengt << 
991                 << CurrentB_PointVelocity.GetC << 
992                 << " - Needed: "  << substep_n << 
993                 << "          Warning number = << 
994                 << " and maximum substeps = "  << 
995         G4Exception(MethodName, "GeomNav1002", << 
996      }                                         << 
997   }                                            << 
998                                                << 
999   return  (!there_is_no_intersection) && found << 
1000     //  Success or failure                    << 
1001 }                                             << 
1002                                               << 
1003 void G4MultiLevelLocator::ReportStatistics()  << 
1004 {                                             << 
1005    G4cout << " Number of calls = " << fNumCal << 
1006    G4cout << " Number of split level ('advanc << 
1007           << fNumAdvanceTrials << G4endl;     << 
1008    G4cout << " Number of full advances:       << 
1009           << fNumAdvanceGood << G4endl;       << 
1010    G4cout << " Number of good advances:       << 
1011           << fNumAdvanceFull << G4endl;       << 
1012 }                                             << 
1013                                                  677 
1014 void G4MultiLevelLocator::ReportFieldValue( c << 678     if ( ! found_approximate_intersection )
1015                                             c << 679     { 
1016                                             c << 680       recalculatedEndPoint = true;
1017 {                                             << 681       // Return the further valid intersection point -- potentially A ??
1018    enum { maxNumFieldComp = 24 };             << 682       // JA/19 Jan 2006
                                                   >> 683       IntersectedOrRecalculatedFT = CurrentA_PointVelocity;
                                                   >> 684 
                                                   >> 685       G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
                                                   >> 686              << G4endl
                                                   >> 687              << "          Did not convergence after " << substep_no
                                                   >> 688              << " substeps." << G4endl;
                                                   >> 689       G4cout << "          The endpoint was adjused to pointA resulting"
                                                   >> 690              << G4endl
                                                   >> 691              << "          from the last substep: " << CurrentA_PointVelocity
                                                   >> 692              << G4endl;
                                                   >> 693     }
                                                   >> 694 #endif
1019                                                  695 
1020    G4ThreeVector position = locationPV.GetPos << 696     oldprc = G4cout.precision( 10 ); 
1021    G4double startPoint[4] = { position.x(), p << 697     G4double done_len = CurrentA_PointVelocity.GetCurveLength(); 
1022                               locationPV.GetL << 698     G4double full_len = CurveEndPointVelocity.GetCurveLength();
1023    G4double FieldVec[maxNumFieldComp]; // 24  << 699     G4cout << "ERROR - G4MultiLevelLocator::EstimateIntersectionPoint()"
1024    for (double & i : FieldVec)                << 700            << G4endl
1025    {                                          << 701            << "        Undertaken only length: " << done_len
1026      i = 0.0;                                 << 702            << " out of " << full_len << " required." << G4endl;
1027    }                                          << 703     G4cout << "        Remaining length = " << full_len - done_len << G4endl; 
1028    equation->GetFieldValue( startPoint, Field << 704     G4cout.precision( oldprc ); 
1029    G4cout << "  B-field value (" << nameLoc < << 705 
1030           << FieldVec[0] << " " << FieldVec[1 << 706     G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
1031    G4double Emag2= G4ThreeVector( FieldVec[3] << 707                 "UnableToLocateIntersection", FatalException,
1032                                   FieldVec[4] << 708                 "Too many substeps while trying to locate intersection.");
1033                                   FieldVec[5] << 709   }
1034    if( Emag2 > 0.0 )                          << 710   else if( substep_no >= warn_substeps )
1035    {                                          << 711   {  
1036       G4cout << " Electric = " << FieldVec[3] << 712     oldprc = G4cout.precision( 10 ); 
1037                                << FieldVec[4] << 713     G4cout << "WARNING - G4MultiLevelLocator::EstimateIntersectionPoint()"
1038                                << FieldVec[5] << 714            << G4endl
1039    }                                          << 715            << "          Undertaken length: "  
1040    return;                                    << 716            << CurrentB_PointVelocity.GetCurveLength(); 
                                                   >> 717     G4cout << " - Needed: "  << substep_no << " substeps." << G4endl
                                                   >> 718            << "          Warning level = " << warn_substeps
                                                   >> 719            << " and maximum substeps = " << max_substeps << G4endl;
                                                   >> 720     G4Exception("G4MultiLevelLocator::EstimateIntersectionPoint()",
                                                   >> 721                 "DifficultyToLocateIntersection", JustWarning,
                                                   >> 722                 "Many substeps while trying to locate intersection.");
                                                   >> 723     G4cout.precision( oldprc ); 
                                                   >> 724   }
                                                   >> 725   return  !there_is_no_intersection; //  Success or failure
1041 }                                                726 }
1042                                                  727