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SoVRMLBillboard Class Reference

The SoVRMLBillboard class is used for rotating geometry towards the viewpoint. More...

#include <Inventor/VRMLnodes/SoVRMLBillboard.h>

Inheritance diagram for SoVRMLBillboard:
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...
 
 SoVRMLBillboard (void)
 
 SoVRMLBillboard (int numchildren)
 
virtual void doAction (SoAction *action)
 
virtual void callback (SoCallbackAction *action)
 
virtual void GLRender (SoGLRenderAction *action)
 
virtual void getBoundingBox (SoGetBoundingBoxAction *action)
 
virtual void getMatrix (SoGetMatrixAction *action)
 
virtual void pick (SoPickAction *action)
 
virtual void search (SoSearchAction *action)
 
virtual void GLRenderBelowPath (SoGLRenderAction *action)
 
virtual void GLRenderInPath (SoGLRenderAction *action)
 
virtual void GLRenderOffPath (SoGLRenderAction *action)
 
virtual void notify (SoNotList *list)
 
- 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 write (SoWriteAction *action)
 
virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action)
 
- Public Member Functions inherited from SoGroup
 SoGroup (void)
 
 SoGroup (int nchildren)
 
virtual void handleEvent (SoHandleEventAction *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 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 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

SoSFVec3f axisOfRotation
 
SoSFVec3f bboxCenter
 
SoSFVec3f bboxSize
 
- Public Attributes inherited from SoVRMLParent
SoMFNode children
 

Protected Member Functions

virtual const SoFieldDatagetFieldData (void) const
 
virtual ~SoVRMLBillboard ()
 
- Protected Member Functions inherited from SoVRMLParent
 SoVRMLParent (void)
 
 SoVRMLParent (int approxchildren)
 
virtual ~SoVRMLParent ()
 
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
SoChildListchildren
 
- 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 SoVRMLBillboard class is used for rotating geometry towards the viewpoint.

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:

Billboard {
  eventIn      MFNode   addChildren
  eventIn      MFNode   removeChildren
  exposedField SFVec3f  axisOfRotation 0 1 0     # (-inf, inf)
  exposedField MFNode   children       []
  field        SFVec3f  bboxCenter     0 0 0     # (-inf, inf)
  field        SFVec3f  bboxSize       -1 -1 -1  # (0, inf) or -1,-1,-1
}

The Billboard node is a grouping node which modifies its coordinate system so that the Billboard node's local Z-axis turns to point at the viewer. The Billboard node has children which may be other children nodes. The axisOfRotation field specifies which axis to use to perform the rotation. This axis is defined in the local coordinate system. When the axisOfRotation field is not (0, 0, 0), the following steps describe how to rotate the billboard to face the viewer:

  • a. Compute the vector from the Billboard node's origin to the viewer's position. This vector is called the billboard-to-viewer vector.
  • b. Compute the plane defined by the axisOfRotation and the billboard-to-viewer vector.
  • c. Rotate the local Z-axis of the billboard into the plane from b., pivoting around the axisOfRotation.

When the axisOfRotation field is set to (0, 0, 0), the special case of viewer-alignment is indicated. In this case, the object rotates to keep the billboard's local Y-axis parallel with the Y-axis of the viewer. This special case is distinguished by setting the axisOfRotation to (0, 0, 0). The following steps describe how to align the billboard's Y-axis to the Y-axis of the viewer:

  • d. Compute the billboard-to-viewer vector.
  • e. Rotate the Z-axis of the billboard to be collinear with the billboard-to-viewer vector and pointing towards the viewer's position.
  • f. Rotate the Y-axis of the billboard to be parallel and oriented in the same direction as the Y-axis of the viewer.

If the axisOfRotation and the billboard-to-viewer line are coincident, the plane cannot be established and the resulting rotation of the billboard is undefined. For example, if the axisOfRotation is set to (0,1,0) (Y-axis) and the viewer flies over the billboard and peers directly down the Y-axis, the results are undefined. Multiple instances of Billboard nodes (DEF/USE) operate as expected: each instance rotates in its unique coordinate system to face the viewer. Subclause 4.6.5, Grouping and children nodes (http://www.web3d.org/documents/specifications/14772/V2.0/part1/concepts.html#4.6.5), provides a description of the children, addChildren, and removeChildren fields and eventIns. The bboxCenter and bboxSize fields specify a bounding box that encloses the Billboard node'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. A default bboxSize value, (-1, -1, -1), implies that the bounding box is not specified and if needed shall be calculated by the browser. A description of the bboxCenter and bboxSize fields is contained in 4.6.4, Bounding boxes (http://www.web3d.org/documents/specifications/14772/V2.0/part1/concepts.html#4.6.4),

The rest of this class documentation is not from the VRML97 standards documentation, but was written specifically for the Coin3D API documentation.

The following example VRML scene is a simple illustration of how SoVRMLBillboard::axisOfRotation constrains rotation around the given vector:

#VRML V2.0 utf8

Transform {
   translation -2 0 0
   children [
      Billboard {
        children [ Box { } ]
      }
   ]
}

Transform {
   translation 2 0 0
   children [
      Billboard {
        axisOfRotation 0 1 0
        children [ Box { } ]
      }
   ]
}

Transform {
   translation 0 -2 0
   children [ Box { size 10 0.1 10 } ]
}

Constructor & Destructor Documentation

◆ SoVRMLBillboard() [1/2]

SoVRMLBillboard::SoVRMLBillboard ( void  )

Constructor.

◆ SoVRMLBillboard() [2/2]

SoVRMLBillboard::SoVRMLBillboard ( int  numchildren)

Constructor. numchildren is the expected number of children.

◆ ~SoVRMLBillboard()

SoVRMLBillboard::~SoVRMLBillboard ( )
protectedvirtual

Destructor.

Member Function Documentation

◆ getTypeId()

SoType SoVRMLBillboard::getTypeId ( void  ) const
virtual

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 * SoVRMLBillboard::getFieldData ( void  ) const
protectedvirtual

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

Reimplemented from SoVRMLParent.

◆ doAction()

void SoVRMLBillboard::doAction ( SoAction action)
virtual

This function performs the typical operation of a node for any action.

Reimplemented from SoVRMLParent.

◆ callback()

void SoVRMLBillboard::callback ( SoCallbackAction action)
virtual

Action method for SoCallbackAction.

Simply updates the state according to how the node behaves for the render action, so the application programmer can use the SoCallbackAction for extracting information about the scene graph.

Reimplemented from SoGroup.

◆ GLRender()

void SoVRMLBillboard::GLRender ( SoGLRenderAction action)
virtual

Action method for the SoGLRenderAction.

This is called during rendering traversals. Nodes influencing the rendering state in any way or want to throw geometry primitives at OpenGL override this method.

Reimplemented from SoGroup.

◆ getBoundingBox()

void SoVRMLBillboard::getBoundingBox ( SoGetBoundingBoxAction action)
virtual

Action method for the SoGetBoundingBoxAction.

Calculates bounding box and center coordinates for node and modifies the values of the action to encompass the bounding box for this node and to shift the center point for the scene more towards the one for this node.

Nodes influencing how geometry nodes calculate their bounding box also override this method to change the relevant state variables.

Reimplemented from SoGroup.

◆ getMatrix()

void SoVRMLBillboard::getMatrix ( SoGetMatrixAction action)
virtual

Action method for SoGetMatrixAction.

Updates action by accumulating with the transformation matrix of this node (if any).

Reimplemented from SoGroup.

◆ pick()

void SoVRMLBillboard::pick ( SoPickAction action)
virtual

Action method for SoPickAction.

Does common processing for SoPickAction action instances.

Reimplemented from SoGroup.

◆ search()

void SoVRMLBillboard::search ( SoSearchAction action)
virtual

Action method for SoSearchAction.

Compares the search criteria from the action to see if this node is a match. Searching is done by matching up all criteria set up in the SoSearchAction – if any of the requested criteria is a miss, the search is not deemed successful for the node.

See also
SoSearchAction

Reimplemented from SoVRMLParent.

◆ GLRenderBelowPath()

void SoVRMLBillboard::GLRenderBelowPath ( SoGLRenderAction action)
virtual

Implements the SoAction::BELOW_PATH traversal method for the rendering action.

Reimplemented from SoNode.

◆ GLRenderInPath()

void SoVRMLBillboard::GLRenderInPath ( SoGLRenderAction action)
virtual

Implements the SoAction::IN_PATH traversal method for the rendering action.

Reimplemented from SoNode.

◆ GLRenderOffPath()

void SoVRMLBillboard::GLRenderOffPath ( SoGLRenderAction action)
virtual

Implements the SoAction::OFF_PATH traversal method for the rendering action.

Reimplemented from SoNode.

◆ notify()

void SoVRMLBillboard::notify ( SoNotList l)
virtual

Notifies all auditors for this instance when changes are made.

Reimplemented from SoVRMLParent.

Member Data Documentation

◆ axisOfRotation

SoSFVec3f SoVRMLBillboard::axisOfRotation

The axis of rotation for the geometry.

◆ bboxCenter

SoSFVec3f SoVRMLBillboard::bboxCenter

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

◆ bboxSize

SoSFVec3f SoVRMLBillboard::bboxSize

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


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