SoPath Class Reference
[General]
Path that points to a list of hierarchical nodes. More...
#include <Inventor/SoPath.h>
Public Member Functions | |
| 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 |
| SoNode * | getNode (const SoType type, int &i) const |
| SoNode * | getNodeFromTail (int i) const |
| int | getIndex (int i) const |
| int | getInstanceIndex (int i) const |
| int | getIndexFromTail (int i) const |
| int | getInstanceIndexFromTail (int i) const |
| int | getLength () const |
| void | truncate (int start) |
| SbBool | containsNode (const SoNode *node) const |
| SbBool | containsNode (const SoType type) const |
| SbBool | containsPath (const SoPath *path) const |
| int | findFork (const SoPath *path) const |
| SoPath * | copy (int startFromNodeIndex=0, int numNodes=0) const |
| virtual SoType | getTypeId () const |
Static Public Member Functions | |
| static SoType | getClassTypeId () |
| static SoPath * | getByName (const SbName &name) |
| static int | getByName (const SbName &name, SoPathList &list) |
Friends | |
| class | SoFullPath |
| class | SoTempPath |
| class | SoAction |
| class | SoPathNoRef |
| class | SoTraversalPassImpl |
| int | operator== (const SoPath &p1, const SoPath &p2) |
| std::ostream & | operator<< (std::ostream &os, const SoPath &path) |
| bool | operator< (const SoPath &p1, const SoPath &p2) |
Detailed Description
Path that points to a list of hierarchical nodes.
A path represents a scene graph or subgraph. It contains a list of nodes forming a chain from some root to some descendant. 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.
Hidden children
Note that only public children of nodes are accessible from an SoPath. Nodes like node kits limit access to their children and these "hidden children" will not be visible using the SoPath methods.
For example, if your application does picking and gets a path from SoRayPickAction, the actual last node in the path (tail) will normally be a shape node. But if that shape is part of a node kit, then the getTail() method will return the node kit, not the shape node. To access all hidden children in the path, simply cast the path object to SoFullPath before calling get methods. To access hidden node kit children (but not all children) in the path, cast the path object to SoNodeKitPath before calling get methods.
[C++] Reference counting:
- This is a reference counted object, similar to a node. It can only be destroyed by incrementing and decrementing the reference count. The initial reference count is 0. You may use the ref() and unref() methods or the SoRef "smart pointer" template.
- SoPath automatically calls ref() when a node is added to the path and unref() when the node is removed from the path or the path object is destroyed. This additional ref() will prevent nodes from being destroyed as long as the path object exists.
- Actions that return an SoPath, for example SoSearchAction and SoRayPickAction, automatically call ref() when the path is created and unref() when the action is reset or destroyed. The application does not need to explicitly destroy these paths. But be aware that as long as the action is not reset or destroyed, the path is not destroyed and so the nodes referenced by the path cannot be destroyed. See the SoAction method clearApplyResult().
FILE FORMAT/DEFAULT
- 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.
SoPath is not able to write "per instance" information to a file for instancing nodes like SoMultipleInstance and SoMultipleCopy. The saved path will reference the whole set of instances under SoMultipleInstance or SoMulitpleCopy node.
SEE ALSO
SoFullPath, SoNode, SoRayPickAction, SoSearchAction, SoNodeKitPath
Constructor & Destructor Documentation
| SoPath::SoPath | ( | ) |
Constructs an empty path.
| SoPath::SoPath | ( | int | approxLength | ) |
Constructs a path with a hint to length (number of nodes in chain).
| SoPath::SoPath | ( | SoNode * | node | ) |
Constructs a path and sets the head node to the given node.
Member Function Documentation
| void SoPath::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.
Reimplemented in SoNodeKitPath.
| void SoPath::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 SoPath::append | ( | int | childIndex | ) |
Adds node to end of chain; the node is the childIndex'th child of the current tail node.
Returns TRUE if the node type is found anywhere in the path chain.
Returns TRUE if the node is found anywhere in the path chain.
Returns TRUE if the nodes in the chain in the passed path are contained (in consecutive order) in this path chain.
| SoPath* 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.
| int SoPath::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.
Reimplemented in SoNodeKitPath.
| static int SoPath::getByName | ( | const SbName & | name, | |
| SoPathList & | list | |||
| ) | [static] |
Method to return paths with a given name.
Paths are named by calling their setName() method (defined by the SoBase class). This method 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.
Method to return a path with a given name.
Paths are named by calling their setName() method (defined by the SoBase class). This method returns the last path that was given the specified 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.
| static SoType SoPath::getClassTypeId | ( | ) | [static] |
| SoNode* SoPath::getHead | ( | ) | const [inline] |
Returns the first node in a path chain.
| int SoPath::getIndex | ( | int | i | ) | const |
Returns the index of the i'th node (within its parent) in the chain.
| int SoPath::getIndexFromTail | ( | int | i | ) | const |
Returns 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 index of the tail node.
Reimplemented in SoFullPath.
| int SoPath::getInstanceIndex | ( | int | i | ) | const |
Returns the index of the instance inside the parent SoMultipleInstance, SoMultipleCopy or SoArray group.
The returned value is -1 for other parent nodes.
| int SoPath::getInstanceIndexFromTail | ( | int | i | ) | const |
Returns the index of the i'th node instance (within its parent, if it is a SoMultipleInstance, SoMultipleCopy or SoArray group in the chain, counting backward from the tail node.
Passing 0 for i returns the instance index of the tail node.
Reimplemented in SoFullPath.
| int SoPath::getLength | ( | ) | const |
Returns length of path chain (number of nodes).
Reimplemented in SoNodeKitPath, and SoFullPath.
Returns the first node and its index, from the head of the given type in the chain.
NULL is returned and the index is set to -1 if no node of the given type is found.
| SoNode* SoPath::getNode | ( | int | i | ) | const |
Returns the i'th node (within its parent) in the chain.
Calling getNode(0) is equivalent to calling getHead().
Reimplemented in SoNodeKitPath.
| SoNode* SoPath::getNodeFromTail | ( | int | i | ) | const |
Returns the i'th node (within its parent) in the chain, counting backward from the tail node.
Passing 0 for i returns the tail node.
Reimplemented in SoNodeKitPath, and SoFullPath.
| SoNode* SoPath::getTail | ( | ) | const |
Returns the last node in a path chain.
Reimplemented in SoNodeKitPath, and SoFullPath.
| virtual SoType SoPath::getTypeId | ( | ) | const [virtual] |
Returns type identifier for path instance.
Implements SoTypedObject.
| void SoPath::pop | ( | ) |
The push() and pop() methods 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.
Reimplemented in SoNodeKitPath, and SoFullPath.
| void SoPath::push | ( | int | childIndex | ) |
| void SoPath::setHead | ( | SoNode * | node | ) |
| void SoPath::truncate | ( | int | start | ) |
Truncates the path chain, removing all nodes from index start on.
Calling truncate(0) empties the path entirely.
Reimplemented in SoNodeKitPath.
Friends And Related Function Documentation
Returns TRUE is p1 strictly less than p2: to provide a total order operation for SoPath.
| std::ostream& operator<< | ( | std::ostream & | os, | |
| const SoPath & | path | |||
| ) | [friend] |
Writes the path to the specified output stream.
Returns TRUE if all nodes in the two path chains are identical.
Reimplemented in SoNodeKitPath.
friend class SoAction [friend] |
friend class SoFullPath [friend] |
friend class SoPathNoRef [friend] |
friend class SoTempPath [friend] |
Reimplemented in SoFullPath.
friend class SoTraversalPassImpl [friend] |
The documentation for this class was generated from the following file:
- Inventor/SoPath.h