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SoVRMLAnchor Class Reference

The SoVRMLAnchor class is used for linking to other URL resources. More...

#include <Inventor/VRMLnodes/SoVRMLAnchor.h>

Inheritance diagram for SoVRMLAnchor:
SoVRMLParent SoGroup SoNode SoFieldContainer SoBase

Public Member Functions

virtual SoType getTypeId (void) const
 Returns the type identification of an object derived from a class inheriting SoBase. This is used for runtime type checking and "downward" casting. More...
 SoVRMLAnchor (void)
virtual void handleEvent (SoHandleEventAction *action)
- Public Member Functions inherited from SoVRMLParent
virtual SbBool affectsState (void) const
virtual void addChild (SoNode *child)
virtual void insertChild (SoNode *child, int idx)
virtual SoNodegetChild (int idx) const
virtual int findChild (const SoNode *child) const
virtual int getNumChildren (void) const
virtual void removeChild (int idx)
virtual void removeChild (SoNode *child)
virtual void removeAllChildren (void)
virtual void replaceChild (int idx, SoNode *child)
virtual void replaceChild (SoNode *old, SoNode *child)
virtual SoChildListgetChildren (void) const
virtual void doAction (SoAction *action)
virtual void search (SoSearchAction *action)
virtual void write (SoWriteAction *action)
virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action)
- Public Member Functions inherited from SoGroup
 SoGroup (void)
 SoGroup (int nchildren)
virtual void GLRender (SoGLRenderAction *action)
virtual void callback (SoCallbackAction *action)
virtual void getBoundingBox (SoGetBoundingBoxAction *action)
virtual void getMatrix (SoGetMatrixAction *action)
virtual void pick (SoPickAction *action)
virtual void audioRender (SoAudioRenderAction *action)
virtual void addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
- Public Member Functions inherited from SoNode
void setOverride (const SbBool state)
SbBool isOverride (void) const
void setNodeType (const NodeType type)
NodeType getNodeType (void) const
virtual SoNodecopy (SbBool copyconnections=FALSE) const
virtual void GLRenderBelowPath (SoGLRenderAction *action)
virtual void GLRenderInPath (SoGLRenderAction *action)
virtual void GLRenderOffPath (SoGLRenderAction *action)
virtual void rayPick (SoRayPickAction *action)
virtual void grabEventsSetup (void)
virtual void grabEventsCleanup (void)
virtual void startNotify (void)
SbUniqueId getNodeId (void) const
virtual void writeInstance (SoOutput *out)
virtual SoNodeaddToCopyDict (void) const
virtual SoFieldContainercopyThroughConnection (void) const
- Public Member Functions inherited from SoFieldContainer
void setToDefaults (void)
SbBool hasDefaultValues (void) const
SbBool fieldsAreEqual (const SoFieldContainer *container) const
void copyFieldValues (const SoFieldContainer *container, SbBool copyconnections=FALSE)
SbBool set (const char *const fielddata)
void get (SbString &fielddata)
virtual int getFields (SoFieldList &l) const
virtual int getAllFields (SoFieldList &l) const
virtual SoFieldgetField (const SbName &name) const
virtual SoFieldgetEventIn (const SbName &name) const
virtual SoFieldgetEventOut (const SbName &name) const
SbBool getFieldName (const SoField *const field, SbName &name) const
SbBool enableNotify (const SbBool flag)
SbBool isNotifyEnabled (void) const
SbBool set (const char *fielddata, SoInput *input)
void get (SbString &fielddata, SoOutput *out)
virtual SbBool validateNewFieldValue (SoField *field, void *newval)
SbBool getIsBuiltIn (void) const
virtual void getFieldsMemorySize (size_t &managed, size_t &unmanaged) const
void setUserData (void *userdata) const
void * getUserData (void) const
- Public Member Functions inherited from SoBase
void ref (void) const
void unref (void) const
void unrefNoDelete (void) const
int32_t getRefCount (void) const
void touch (void)
SbBool isOfType (SoType type) const
 Returns TRUE if the type of this object is either of the same type or inherited from type. More...
virtual SbName getName (void) const
virtual void setName (const SbName &newname)
void addAuditor (void *const auditor, const SoNotRec::Type type)
void removeAuditor (void *const auditor, const SoNotRec::Type type)
const SoAuditorListgetAuditors (void) const
SbBool shouldWrite (void)
void assertAlive (void) const

Static Public Member Functions

static SoType getClassTypeId (void)
static void initClass (void)
static void setFetchURLCallBack (SoVRMLAnchorCB *, void *closure)
- Static Public Member Functions inherited from SoVRMLParent
static SoType getClassTypeId (void)
static void initClass (void)
static void updateChildList (const SoNode *const *nodes, const int numnodes, SoChildList &cl)
static void updateChildList (SoNode *nodewithsfnode, SoChildList &cl)
- Static Public Member Functions inherited from SoGroup
static SoType getClassTypeId (void)
static void initClass (void)
- Static Public Member Functions inherited from SoNode
static uint32_t getCompatibilityTypes (const SoType &nodetype)
static SoType getClassTypeId (void)
static SoNodegetByName (const SbName &name)
static int getByName (const SbName &name, SoNodeList &l)
static void initClass (void)
static void initClasses (void)
static SbUniqueId getNextNodeId (void)
static int getActionMethodIndex (const SoType type)
static void getBoundingBoxS (SoAction *action, SoNode *node)
static void GLRenderS (SoAction *action, SoNode *node)
static void callbackS (SoAction *action, SoNode *node)
static void getMatrixS (SoAction *action, SoNode *node)
static void handleEventS (SoAction *action, SoNode *node)
static void pickS (SoAction *action, SoNode *node)
static void rayPickS (SoAction *action, SoNode *node)
static void searchS (SoAction *action, SoNode *node)
static void writeS (SoAction *action, SoNode *node)
static void audioRenderS (SoAction *action, SoNode *node)
static void getPrimitiveCountS (SoAction *action, SoNode *node)
- Static Public Member Functions inherited from SoFieldContainer
static void initClass (void)
static SoType getClassTypeId (void)
static void cleanupClass (void)
static void initCopyDict (void)
static void addCopy (const SoFieldContainer *orig, const SoFieldContainer *copy)
static SoFieldContainercheckCopy (const SoFieldContainer *orig)
static SoFieldContainerfindCopy (const SoFieldContainer *orig, const SbBool copyconnections)
static void copyDone (void)
- Static Public Member Functions inherited from SoBase
static void initClass (void)
 Sets up initialization for data common to all instances of this class, like submitting necessary information to the Coin type system.
static SoType getClassTypeId (void)
 This static method returns the SoType object associated with objects of this class.
static void addName (SoBase *const base, const char *const name)
static void removeName (SoBase *const base, const char *const name)
static void incrementCurrentWriteCounter (void)
static void decrementCurrentWriteCounter (void)
static SoBasegetNamedBase (const SbName &name, SoType type)
static int getNamedBases (const SbName &name, SoBaseList &baselist, SoType type)
static SbBool read (SoInput *input, SoBase *&base, SoType expectedtype)
static void setInstancePrefix (const SbString &c)
static void setTraceRefs (SbBool trace)
static SbBool getTraceRefs (void)
static SbBool connectRoute (SoInput *input, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)
static SbBool readRoute (SoInput *input)

Public Attributes

SoMFString url
SoSFString description
SoMFString parameter
SoSFVec3f bboxCenter
SoSFVec3f bboxSize
- Public Attributes inherited from SoVRMLParent
SoMFNode children

Protected Member Functions

virtual const SoFieldDatagetFieldData (void) const
virtual ~SoVRMLAnchor ()
- Protected Member Functions inherited from SoVRMLParent
 SoVRMLParent (void)
 SoVRMLParent (int approxchildren)
virtual ~SoVRMLParent ()
virtual void notify (SoNotList *list)
virtual SbBool readInstance (SoInput *in, unsigned short flags)
virtual void copyContents (const SoFieldContainer *from, SbBool copyConn)
- Protected Member Functions inherited from SoGroup
virtual ~SoGroup ()
virtual SbBool readChildren (SoInput *in)
virtual SoNotRec createNotRec (void)
void setOperation (const SoNotRec::OperationType opType=SoNotRec::UNSPECIFIED, const SoNode *cc=NULL, const SoNode *pc=NULL, const int ci=-1)
- Protected Member Functions inherited from SoNode
 SoNode (void)
virtual ~SoNode ()
- Protected Member Functions inherited from SoFieldContainer
 SoFieldContainer (void)
virtual ~SoFieldContainer ()
- Protected Member Functions inherited from SoBase
 SoBase (void)
virtual ~SoBase ()
virtual void destroy (void)
SbBool hasMultipleWriteRefs (void) const
SbBool writeHeader (SoOutput *out, SbBool isgroup, SbBool isengine) const
void writeFooter (SoOutput *out) const
virtual const char * getFileFormatName (void) const

Static Protected Member Functions

static const SoFieldData ** getFieldDataPtr (void)
- Static Protected Member Functions inherited from SoVRMLParent
static const SoFieldData ** getFieldDataPtr (void)
- Static Protected Member Functions inherited from SoGroup
static const SoFieldData ** getFieldDataPtr (void)
- Static Protected Member Functions inherited from SoNode
static const SoFieldData ** getFieldDataPtr (void)
static void setNextActionMethodIndex (int index)
static int getNextActionMethodIndex (void)
static void incNextActionMethodIndex (void)
static void setCompatibilityTypes (const SoType &nodetype, const uint32_t bitmask)
- Static Protected Member Functions inherited from SoBase
static uint32_t getCurrentWriteCounter (void)
static void staticDataLock (void)
static void staticDataUnlock (void)

Additional Inherited Members

- Public Types inherited from SoNode
enum  NodeType {
  INVENTOR = 0x0000, VRML1 = 0x0001, VRML2 = 0x0002, INVENTOR_1 = 0x0004,
  INVENTOR_2_0 = 0x0008, INVENTOR_2_1 = 0x0010, INVENTOR_2_5 = 0x0020, INVENTOR_2_6 = 0x0040,
  COIN_1_0 = 0x0080, COIN_2_0 = 0x0100, EXTENSION = 0x0200, COIN_2_2 = 0x0400,
  COIN_2_3 = 0x0800, COIN_2_4 = 0x1000, INVENTOR_5_0 = 0x2000, COIN_2_5 = 0x4000,
  COIN_3_0 = 0x8000, INVENTOR_6_0 = 0x10000, COIN_4_0 = 0x20000
- Protected Types inherited from SoBase
enum  BaseFlags { IS_ENGINE = 0x01, IS_GROUP = 0x02 }
- Protected Attributes inherited from SoVRMLParent
SoMFNode addChildren
SoMFNode removeChildren
- Protected Attributes inherited from SoGroup
- Protected Attributes inherited from SoNode
SbUniqueId uniqueId
- Protected Attributes inherited from SoFieldContainer
SbBool isBuiltIn
- Static Protected Attributes inherited from SoNode
static SbUniqueId nextUniqueId = 1
static int nextActionMethodIndex = 0

Detailed Description

The SoVRMLAnchor class is used for linking to other URL resources.

The detailed class documentation is taken verbatim from the VRML97 standard (ISO/IEC 14772-1:1997). It is copyright The Web3D Consortium, and is used by permission of the Consortium:

Anchor {
  eventIn      MFNode   addChildren
  eventIn      MFNode   removeChildren
  exposedField MFNode   children        []
  exposedField SFString description     ""
  exposedField MFString parameter       []
  exposedField MFString url             []
  field        SFVec3f  bboxCenter      0 0 0     # (-inf, inf)
  field        SFVec3f  bboxSize        -1 -1 -1  # (0, inf) or -1,-1,-1

The Anchor grouping node retrieves the content of a URL when the user activates (e.g., clicks) some geometry contained within the Anchor node's children. If the URL points to a valid VRML file, that world replaces the world of which the Anchor node is a part (except when the parameter field, described below, alters this behaviour). If non-VRML data is retrieved, the browser shall determine how to handle that data; typically, it will be passed to an appropriate non-VRML browser. Exactly how a user activates geometry contained by the Anchor node depends on the pointing device and is determined by the VRML browser. Typically, clicking with the pointing device will result in the new scene replacing the current scene. An Anchor node with an empty url does nothing when its children are chosen. A description of how multiple Anchors and pointing-device sensors are resolved on activation is contained in 4.6.7, Sensor nodes (

More details on the children, addChildren, and removeChildren fields and eventIns can be found in 4.6.5, Grouping and children nodes (

The description field in the Anchor node specifies a textual description of the Anchor node. This may be used by browser-specific user interfaces that wish to present users with more detailed information about the Anchor. The parameter exposed field may be used to supply any additional information to be interpreted by the browser. Each string shall consist of "keyword=value" pairs. For example, some browsers allow the specification of a 'target' for a link to display a link in another part of an HTML document. The parameter field is then:

Anchor {
  parameter [ "target=name_of_frame" ]

An Anchor node may be used to bind the initial Viewpoint node in a world by specifying a URL ending with "#ViewpointName" where "ViewpointName" is the name of a viewpoint defined in the VRML file. For example:

Anchor {
  url ""
  children  Shape { geometry Box {} }

specifies an anchor that loads the VRML file "someScene.wrl" and binds the initial user view to the Viewpoint node named "OverView" when the Anchor node's geometry (Box) is activated. If the named Viewpoint node is not found in the VRML file, the VRML file is loaded using the default Viewpoint node binding stack rules (see VRMLViewpoint). If the url field is specified in the form "#ViewpointName" (i.e. no file name), the Viewpoint node with the given name ("ViewpointName") in the Anchor's runtime name scope(s) shall be bound (set_bind TRUE). The results are undefined if there are multiple Viewpoints with the same name in the Anchor's runtime name scope(s). The results are undefined if the Anchor node is not part of any runtime name scope or is part of more than one runtime name scope. See 4.4.6, Runtime name scope, for a description of runtime name scopes. See VRMLViewpoint, for the Viewpoint transition rules that specify how browsers shall interpret the transition from the old Viewpoint node to the new one. For example:

Anchor {
  url "#Doorway"
  children Shape {
    geometry Sphere {}

binds the viewer to the viewpoint defined by the "Doorway" viewpoint in the current world when the sphere is activated. In this case, if the Viewpoint is not found, no action occurs on activation. More details on the url field are contained in 4.5, VRML and the World Wide Web ( The bboxCenter and bboxSize fields specify a bounding box that encloses the Anchor's children. This is a hint that may be used for optimization purposes. The results are undefined if the specified bounding box is smaller than the actual bounding box of the children at any time. The default bboxSize value, (-1, -1, -1), implies that the bounding box is not specified and if needed shall be calculated by the browser. More details on the bboxCenter and bboxSize fields can be found in 4.6.4, Bounding boxes (

Constructor & Destructor Documentation

◆ SoVRMLAnchor()

SoVRMLAnchor::SoVRMLAnchor ( void  )

Default constructor.

◆ ~SoVRMLAnchor()

SoVRMLAnchor::~SoVRMLAnchor ( )


Member Function Documentation

◆ getTypeId()

SoType SoVRMLAnchor::getTypeId ( void  ) const

Returns the type identification of an object derived from a class inheriting SoBase. This is used for runtime type checking and "downward" casting.

Usage example:

void foo(SoNode * node)
if (node->getTypeId() == SoFile::getClassTypeId()) {
SoFile * filenode = (SoFile *)node; // safe downward cast, knows the type

For application programmers wanting to extend the library with new nodes, engines, nodekits, draggers or others: this method needs to be overridden in all subclasses. This is typically done as part of setting up the full type system for extension classes, which is usually accomplished by using the predefined macros available through for instance Inventor/nodes/SoSubNode.h (SO_NODE_INIT_CLASS and SO_NODE_CONSTRUCTOR for node classes), Inventor/engines/SoSubEngine.h (for engine classes) and so on.

For more information on writing Coin extensions, see the class documentation of the top level superclasses for the various class groups.

Reimplemented from SoVRMLParent.

◆ getFieldData()

const SoFieldData * SoVRMLAnchor::getFieldData ( void  ) const

Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL.

Reimplemented from SoVRMLParent.

◆ setFetchURLCallBack()

void SoVRMLAnchor::setFetchURLCallBack ( SoVRMLAnchorCB *  f,
void *  closure 

Sets the callback that will be called when the node is selected.

◆ handleEvent()

void SoVRMLAnchor::handleEvent ( SoHandleEventAction action)

Action method for SoHandleEventAction.

Inspects the event data from action, and processes it if it is something which this node should react to.

Nodes influencing relevant state variables for how event handling is done also override this method.

Reimplemented from SoGroup.

Member Data Documentation

◆ url


The URL string.

◆ description


The textual description of the URL.

◆ parameter


May be used to supply additional information to the browser.

Each string should be pairs of keyword = value.

◆ bboxCenter


Children bounding box hint center. Default value is (0, 0, 0).

◆ bboxSize


Children bounding box size hint. Default value is (-1, -1, -1).

The documentation for this class was generated from the following files: