trusty (3) SoPath.3iv.gz

Provided by: inventor-doc_2.1.5-10-18_all bug

NAME

       SoPath — path that points to a list of hierarchical nodes

INHERITS FROM

       SoBase > SoPath

SYNOPSIS

       #include <Inventor/SoPath.h>

          Methods from class SoPath:

                         SoPath()
                         SoPath(int approxLength)
                         SoPath(SoNode *node)
     void                setHead(SoNode *node)
     void                append(int childIndex)
     void                append(SoNode *childNode)
     void                append(const SoPath *fromPath)
     void                push(int childIndex)
     void                pop()
     SoNode *            getHead() const
     SoNode *            getTail() const
     SoNode *            getNode(int i) const
     int                 getIndex(int i) const
     SoNode *            getNodeFromTail(int i) const
     int                 getIndexFromTail(int i) const
     int                 getLength() const
     void                truncate(int start)
     SbBool              containsNode(const SoNode *node) const
     SbBool              containsPath(const SoPath *path) const
     int                 findFork(const SoPath *path) const
     SoPath *            copy(int startFromNodeIndex = 0, int numNodes = 0) const
     friend int          operator ==(const SoPath &p1, const SoPath &p2)
     static SoPath *     getByName(const SbName &name)
     static int          getByName(const SbName &name, SoPathList &list)

          Methods from class SoBase:

     void                ref()
     void                unref() const
     void                unrefNoDelete() const
     void                touch()
     static SoType       getClassTypeId()
     virtual SoType      getTypeId() const
     SbBool              isOfType(SoType type) const
     virtual void        setName(const SbName &name)
     virtual SbName      getName() const

DESCRIPTION

       A path represents a scene graph or subgraph. It contains a list of pointers to nodes forming a chain from
       some root to some descendent. Each node in the chain is a child of the previous node. Paths are  used  to
       refer  to  some  object in a scene graph precisely and unambiguously, even if there are many instances of
       the object. Therefore, paths are returned by both the SoRayPickAction and SoSearchAction.

       When an action is applied to a path, only the nodes in the subgraph defined by the  path  are  traversed.
       These  include:  the nodes in the path chain, all nodes (if any) below the last node in the path, and all
       nodes whose effects are inherited by any of these nodes.

       SoPath attempts to maintain consistency of paths even when the structure of the scene graph changes.  For
       example,  removing  a  child  from  its  parent when both are in a path chain cuts the path chain at that
       point, leaving the top part intact. Removing the node to the left of a node in a path adjusts  the  index
       for  that  node. Replacing a child of a node when both the parent and the child are in the chain replaces
       the child in the chain with the new child, truncating the path below the new child.

       Note that only public children of nodes are accessible from an SoPath. Nodes like node  kits  that  limit
       access  to  their  children  may  provide  other  ways  to  get  more  information,  such as by using the
       SoNodeKitPath class.

METHODS

                         SoPath()
          Constructs an empty path.

                         SoPath(int approxLength)
          Constructs a path with a hint to length (number of nodes in chain).

                         SoPath(SoNode *node)
          Constructs a path and sets the head node to the given node.

     void                setHead(SoNode *node)
          Sets head node (first node in chain). The head node must be set before the append() or push()  methods
          may be called.

     void                append(int childIndex)
          Adds node to end of chain; the node is the childIndex'th child of the current tail node.

     void                append(SoNode *childNode)
          Adds  node  to  end of chain; uses the first occurrence of childNode as child of current tail node. If
          the path is empty, this is equivalent to setHead(childNode).

     void                append(const SoPath *fromPath)
          Adds all nodes in fromPath's chain to end of chain; the head node of fromPath must be the same as or a
          child of the current tail node.

     void                push(int childIndex)
     void                pop()
          These allow a path to be treated as a stack; they push a node at the end of the chain and pop the last
          node off.

     SoNode *            getHead() const
     SoNode *            getTail() const
          These return the first and last nodes in a path chain.

     SoNode *            getNode(int i) const
     int                 getIndex(int i) const
          These return a pointer to the i'th node or the index of the i'th  node  (within  its  parent)  in  the
          chain. Calling getNode(0) is equivalent to calling getHead().

     SoNode *            getNodeFromTail(int i) const
     int                 getIndexFromTail(int i) const
          These  return  a  pointer  to  the  i'th node or the index of the i'th node (within its parent) in the
          chain, counting backward from the tail node. Passing 0 for i returns the tail node or its index.

     int                 getLength() const
          Returns length of path chain (number of nodes).

     void                truncate(int start)
          Truncates the path chain, removing all nodes from index start on.  Calling  truncate(0)   empties  the
          path entirely.

     SbBool              containsNode(const SoNode *node) const
          Returns TRUE if the node is found anywhere in the path chain.

     SbBool              containsPath(const SoPath *path) const
          Returns TRUE if the nodes in the chain in the passed path are contained (in consecutive order) in this
          path chain.

     int                 findFork(const SoPath *path) const
          If the two paths have different head nodes, this returns -1. Otherwise,  it  returns  the  path  chain
          index of the last node (starting at the head) that is the same for both paths.

     SoPath *            copy(int startFromNodeIndex = 0, int numNodes = 0) const
          Creates and returns a new path that is a copy of some or all of this path. Copying starts at the given
          index (default is 0, which is the head node). A numNodes of 0 (the default) means copy all nodes  from
          the starting index to the end. Returns NULL on error.

     friend int          operator ==(const SoPath &p1, const SoPath &p2)
          Returns TRUE if all node pointers in the two path chains are identical.

     static SoPath *     getByName(const SbName &name)
     static int          getByName(const SbName &name, SoPathList &list)
          These  methods  lookup  and return paths with a given name. Paths are named by calling their setName()
          method (defined by the SoBase class). The first form returns the last path that was given  that  name,
          either  by  setName()  or  by  reading in a named path from a file. If there is no path with the given
          name, NULL will be returned. The second form appends all paths with the given name to the  given  path
          list  and returns the number of paths that were added. If there are no paths with the given name, zero
          will be returned and nothing will be added to the list.

FILE FORMAT/DEFAULTS

       SoPath {
          [head node]
          [number of remaining indices]
          [index]
          ...
          [index]
     }

     Note that the indices in a written path are adjusted based on the nodes that  are  actually  written  to  a
     file.  Since  nodes  in  the  graph  that have no effect on the path (such as some separator nodes) are not
     written, the siblings of such nodes must undergo index adjustment when written. The  actual  nodes  in  the
     graph remain unchanged.

SEE ALSO

       SoNode, SoRayPickAction, SoSearchAction, SoNodeKitPath

                                                                                                   SoPath(3IV)()