Geant4 Navigator

• Hmm, very wide API (an internal class) : dont touch

source/geometry/navigation/include/G4Navigator.hh:

030 // class G4Navigator
031 //
032 // Class description:
033 //
034 // A class for use by the tracking management, able to obtain/calculate
035 // dynamic tracking time information such as the distance to the next volume,
036 // or to find the physical volume containing a given point in the world
037 // reference system. The navigator maintains a transformation history and
038 // other information to optimise the tracking time performance.
039
040 // History:
041 // - Created.                                  Paul Kent,     Jul 95/96
042 // - Zero step protections                     J.A. / G.C.,   Nov  2004
043 // - Added check mode                          G. Cosmo,      Mar  2004
044 // - Made Navigator Abstract                   G. Cosmo,      Nov  2003
045 // *********************************************************************
...
085   virtual G4double ComputeStep(const G4ThreeVector &pGlobalPoint,
086                                const G4ThreeVector &pDirection,
087                                const G4double pCurrentProposedStepLength,
088                                      G4double  &pNewSafety);
089     // Calculate the distance to the next boundary intersected
090     // along the specified NORMALISED vector direction and
091     // from the specified point in the global coordinate
092     // system. LocateGlobalPointAndSetup or LocateGlobalPointWithinVolume
093     // must have been called with the same global point prior to this call.
094     // The isotropic distance to the nearest boundary is also
095     // calculated (usually an underestimate). The current
096     // proposed Step length is used to avoid intersection
097     // calculations: if it can be determined that the nearest
098     // boundary is >pCurrentProposedStepLength away, kInfinity
099     // is returned together with the computed isotropic safety
100     // distance. Geometry must be closed.
101
102   G4double CheckNextStep(const G4ThreeVector &pGlobalPoint,
103                          const G4ThreeVector &pDirection,
104                          const G4double pCurrentProposedStepLength,
105                                G4double &pNewSafety);
106     // Same as above, but do not disturb the state of the Navigator.
107
108   virtual
109   G4VPhysicalVolume* ResetHierarchyAndLocate(const G4ThreeVector &point,
110                                              const G4ThreeVector &direction,
111                                              const G4TouchableHistory &h);
112
113     // Resets the geometrical hierarchy and search for the volumes deepest
114     // in the hierarchy containing the point in the global coordinate space.
115     // The direction is used to check if a volume is entered.
116     // The search begin is the geometrical hierarchy at the location of the
117     // last located point, or the endpoint of the previous Step if
118     // SetGeometricallyLimitedStep() has been called immediately before.
119     //
120     // Important Note: In order to call this the geometry MUST be closed.
121
122   virtual
123   G4VPhysicalVolume* LocateGlobalPointAndSetup(const G4ThreeVector& point,
124                                              const G4ThreeVector* direction=0,
125                                              const G4bool pRelativeSearch=true,
126                                              const G4bool ignoreDirection=true);
127     // Search the geometrical hierarchy for the volumes deepest in the hierarchy
128     // containing the point in the global coordinate space. Two main cases are:
129     //  i) If pRelativeSearch=false it makes use of no previous/state
130     //     information. Returns the physical volume containing the point,
131     //     with all previous mothers correctly set up.
132     // ii) If pRelativeSearch is set to true, the search begin is the
133     //     geometrical hierarchy at the location of the last located point,
134     //     or the endpoint of the previous Step if SetGeometricallyLimitedStep()
135     //     has been called immediately before.
136     // The direction is used (to check if a volume is entered) if either
137     //   - the argument ignoreDirection is false, or
138     //   - the Navigator has determined that it is on an edge shared by two or
139     //     more volumes.  (This is state information.)
140     //
141     // Important Note: In order to call this the geometry MUST be closed.
142
143   virtual
144   void LocateGlobalPointWithinVolume(const G4ThreeVector& position);
145     // Notify the Navigator that a track has moved to the new Global point
146     // 'position', that is known to be within the current safety.
147     // No check is performed to ensure that it is within  the volume.
148     // This method can be called instead of LocateGlobalPointAndSetup ONLY if
149     // the caller is certain that the new global point (position) is inside the
150     // same volume as the previous position.  Usually this can be guaranteed
151     // only if the point is within safety.