class TGeoNavigator: public TObject

 dummy constructor

 Default constructor.

 Copy constructor.

assignment operator

 Destructor.

 Builds the cache for physical nodes and global matrices.

 Browse the tree of nodes starting from top node according to pathname.
 Changes the path accordingly.

 Check if a geometry path is valid without changing the state of the navigator.

 Change current path to point to the node having this id.
 Node id has to be in range : 0 to fNNodes-1 (no check for performance reasons)

 Make a daughter of current node current. Can be called only with a valid
 daughter index (no check). Updates cache accordingly.

 Go one level up in geometry. Updates cache accordingly.
 Determine the overlapping state of current node.

 Make top level node the current node. Updates the cache accordingly.
 Determine the overlapping state of current node.

 Do a cd to the node found next by FindNextBoundary

 Fill volume names of current branch into an array.

 Fill node copy numbers of current branch into an array.

 Fill node copy numbers of current branch into an array.

 Cross a division cell. Distance to exit contained in fStep, current node
 points to the cell node.

 Cross next boundary and locate within current node
 The current point must be on the boundary of fCurrentNode.

 Find distance to next boundary and store it in fStep. Returns node to which this
 boundary belongs. If PATH is specified, compute only distance to the node to which
 PATH points. If STEPMAX is specified, compute distance only in case fSafety is smaller
 than this value. STEPMAX represent the step to be made imposed by other reasons than
 geometry (usually physics processes). Therefore in this case this method provides the
 answer to the question : "Is STEPMAX a safe step ?" returning a NULL node and filling
 fStep with a big number.
 In case frombdr=kTRUE, the isotropic safety is set to zero.
 Note : safety distance for the current point is computed ONLY in case STEPMAX is
        specified, otherwise users have to call explicitly TGeoManager::Safety() if
        they want this computed for the current point.

 Computes as fStep the distance to next daughter of the current volume.
 The point and direction must be converted in the coordinate system of the current volume.
 The proposed step limit is fStep.

 Compute distance to next boundary within STEPMAX. If no boundary is found,
 propagate current point along current direction with fStep=STEPMAX. Otherwise
 propagate with fStep=SNEXT (distance to boundary) and locate/return the next
 node.

 Returns deepest node containing current point.

 Returns deepest node containing current point.

 Computes fast normal to next crossed boundary, assuming that the current point
 is close enough to the boundary. Works only after calling FindNextBoundary.

 Computes normal vector to the next surface that will be or was already
 crossed when propagating on a straight line from a given point/direction.
 Returns the normal vector cosines in the MASTER coordinate system. The dot
 product of the normal and the current direction is positive defined.

 Initialize current point and current direction vector (normalized)
 in MARS. Return corresponding node.

 Initialize current point and current direction vector (normalized)
 in MARS. Return corresponding node.

 Reset current state flags.

 Compute safe distance from the current point. This represent the distance
 from POINT to the closest boundary.

 Compute safe distance from the current point within an overlapping node

 Returns the deepest node containing fPoint, which must be set a priori.

 Find a node inside a cluster of overlapping nodes. Current node must
 be on top of all the nodes in cluster. Always nc>1.

 Make the cluster of overlapping nodes in a voxel, containing point in reference
 of the mother. Returns number of nodes containing the point. Nodes should not be
 offsets.

 Make a rectiliniar step of length fStep from current point (fPoint) on current
 direction (fDirection). If the step is imposed by geometry, is_geom flag
 must be true (default). The cross flag specifies if the boundary should be
 crossed in case of a geometry step (default true). Returns new node after step.
 Set also on boundary condition.

 Find level of virtuality of current overlapping node (number of levels
 up having the same tracking media.

 Go upwards the tree until a non-overlaping node

 Go upwards the tree until a non-overlaping node

 Inspects path and all flags for the current state.

 Checks if point (x,y,z) is still in the current node.
 check if this is an overlapping node

 In case a previous safety value was computed, check if the safety region is
 still safe for the current point and proposed step. Return value changed only
 if proposed distance is safe.

 Check if a new point with given coordinates is the same as the last located one.

 Backup the current state without affecting the cache stack.

 Restore a backed-up state without affecting the cache stack.

 Return stored current matrix (global matrix of the next touched node).

 Get path to the current node in the form /node0/node1/...

 Convert coordinates from master volume frame to top.

 Convert coordinates from top volume frame to master.

 Reset the navigator.

--- geometry queries

--- modeler state getters/setters

   Double_t               GetNormalChecked() const {return fNormalChecked;}

   void                   SetNormalChecked(Double_t norm) {fNormalChecked=norm;}

--- point/vector reference frame conversion

   void                   SetCache(const TGeoNodeCache *cache) {fCache = (TGeoNodeCache*)cache;}
--- stack manipulation