SoVRMLBillboard(3)

📦 version 3.1.3, in fedora 43, fedora 44

💖 SoVRMLBillboard 💖

okay so bestie, welcome to SoVRMLBillboard(3) — that's the manual page name, from the Library Functions Manual, and it's all about one beautiful little class. grab a snack, this one's a two-parter 🍓

🌸 NAME 🌸

SoVRMLBillboard — the class used for rotating geometry towards the viewpoint. That's it. That's the whole personality. It rotates your geometry so it's looking at you, like a lil sunflower that only faces the camera. iconic behavior honestly 🌻✨

✨ SYNOPSIS ✨

First thing first, you gotta include it:

#include <Inventor/VRMLnodes/SoVRMLBillboard.h>

Inherits SoVRMLParent. so it's got family, it's not out here alone 💜

🫶 Public Member Functions 🫶

here's the whole roster of what SoVRMLBillboard brings to the table itself:

virtual SoType getTypeId (void) const
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)
two constructors, bestie — one with no args and one that takes an int numchildren. pick your fighter 💅

🦋 Public Member Functions inherited from SoVRMLParent 🦋

these are the ones it gets handed down, no effort required:

virtual SbBool affectsState (void) const
virtual void addChild (SoNode *child)
virtual void insertChild (SoNode *child, int idx)
virtual SoNode * getChild (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 SoChildList * getChildren (void) const
virtual void write (SoWriteAction *action)
virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action)

🎀 Public Member Functions inherited from SoGroup 🎀

more inheritance, more slay:

SoGroup (void)
SoGroup (int nchildren)
virtual void handleEvent (SoHandleEventAction *action)
virtual void audioRender (SoAudioRenderAction *action)

💜 Public Member Functions inherited from SoNode 💜

this list is long, but we do not skip, we do not summarise, we read every line:

void setOverride (const SbBool state)
SbBool isOverride (void) const
void setNodeType (const NodeType type)
NodeType getNodeType (void) const
virtual SoNode * copy (SbBool copyconnections=FALSE) const
virtual void rayPick (SoRayPickAction *action)
virtual void grabEventsSetup (void)
virtual void grabEventsCleanup (void)
virtual void startNotify (void)
uint32_t getNodeId (void) const
virtual void writeInstance (SoOutput *out)
virtual SoNode * addToCopyDict (void) const
virtual SoFieldContainer * copyThroughConnection (void) const

🌈 Public Member Functions inherited from SoFieldContainer 🌈

the field management crew has entered the chat:

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 SoField * getField (const SbName &name) const
virtual SoField * getEventIn (const SbName &name) const
virtual SoField * getEventOut (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)
virtual void addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
SbBool getIsBuiltIn (void) const
virtual void getFieldsMemorySize (size_t &managed, size_t &unmanaged)
    const
void setUserData (void *userdata) const
void * getUserData (void) const
yes the getFieldsMemorySize signature really does wrap onto its own line like that. it's giving "couldn't fit". we respect it anyway 🫶

💫 Public Member Functions inherited from SoBase 💫

and the final boss of inheritance:

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
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 SoAuditorList & getAuditors (void) const
SbBool shouldWrite (void)
void assertAlive (void) const

⭐ Static Public Member Functions ⭐

these you can call without making an instance, very convenient, very demure:

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)
yes there are two updateChildLists. that's not a typo, that's an overload. love that for them ✨

🎀 Static Public Member Functions inherited from SoGroup 🎀

static SoType getClassTypeId (void)
static void initClass (void)

🧚 Static Public Member Functions inherited from SoNode 🧚

okay this one is a whole vibe:

static uint32_t getCompatibilityTypes (const SoType &nodetype)
static SoType getClassTypeId (void)
static SoNode * getByName (const SbName &name)
static int getByName (const SbName &name, SoNodeList &l)
static void initClass (void)
static void initClasses (void)
static uint32_t 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 SoFieldContainer * checkCopy (const SoFieldContainer *orig)
static SoFieldContainer * findCopy (const SoFieldContainer *orig, const
    SbBool copyconnections)
static void copyDone (void)

🌸 Static Public Member Functions inherited from SoBase 🌸

the big one. deep breath. here we go:

static void initClass (void)
static SoType getClassTypeId (void)
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 SoBase * getNamedBase (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)
you made it. hydration break. drink some water, you earned it 💧

💅 Public Attributes 💅

these are the fields you actually get to play with on SoVRMLBillboard itself:

SoSFVec3f axisOfRotation
SoSFVec3f bboxCenter
SoSFVec3f bboxSize

🦋 Public Attributes inherited from SoVRMLParent 🦋

SoMFNode children

🫧 Protected Member Functions 🫧

for the subclassers and the brave:

virtual const SoFieldData * getFieldData (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)

✨ 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 🎀

the bonus round. the extras. the little guys at the bottom of the page. 🫶

👑 Public Types inherited from SoNode 👑

the NodeType enum, in all its hexadecimal glory:

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 }
look at those bit flags go. power-of-two realness. no cap 🔥

🦋 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 🎀

SoChildList * children

✨ Protected Attributes inherited from SoNode ✨

uint32_t uniqueId

💜 Protected Attributes inherited from SoFieldContainer 💜

SbBool isBuiltIn

🌟 Static Protected Attributes inherited from SoNode 🌟

static uint32_t nextUniqueId = 1
static int nextActionMethodIndex = 0

and that's the whole member roster, bestie — every function, every attribute, every enum value, all accounted for. 💅✨

✨ 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.
🚨 ok bestie listen — 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. no cap.

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/x3d/specifications/vrml/ISO-IEC-14772-VRML97/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/x3d/specifications/vrml/ISO-IEC-14772-VRML97/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::SoVRMLBillboard (void )

Constructor. 💖

SoVRMLBillboard::SoVRMLBillboard (int numchildren)

Constructor. numchildren is the expected number of children.

SoVRMLBillboard::~SoVRMLBillboard () [protected], [virtual]

Destructor. 🫶

💅 Member Function Documentation 💅

SoType SoVRMLBillboard::getTypeId (void ) const [virtual]

Returns the type identification of an object derived from a class inheriting SoBase. This is used for run-time 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 pre-defined 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 toplevel superclasses for the various class groups.

Reimplemented from SoVRMLParent.

const SoFieldData * SoVRMLBillboard::getFieldData (void ) const [protected], [virtual]

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

Reimplemented from SoVRMLParent.

void SoVRMLBillboard::doAction (SoAction * action) [virtual]

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

Reimplemented from SoVRMLParent.

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.

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 who wants to throw geometry primitives at OpenGL overrides this method.

Reimplemented from SoGroup.

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 calculates their bounding box also overrides this method to change the relevant state variables.

Reimplemented from SoGroup.

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.

void SoVRMLBillboard::pick (SoPickAction * action) [virtual]

Action method for SoPickAction.

Does common processing for SoPickAction action instances.

Reimplemented from SoGroup.

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.

void SoVRMLBillboard::GLRenderBelowPath (SoGLRenderAction * action) [virtual]

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

Reimplemented from SoNode.

void SoVRMLBillboard::GLRenderInPath (SoGLRenderAction * action) [virtual]

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

Reimplemented from SoNode.

void SoVRMLBillboard::GLRenderOffPath (SoGLRenderAction * action) [virtual]

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

Reimplemented from SoNode.

void SoVRMLBillboard::notify (SoNotList * l) [virtual]

Notifies all auditors for this instance when changes are made.

Reimplemented from SoVRMLParent.

🌸 Member Data Documentation 🌸

SoSFVec3f SoVRMLBillboard::axisOfRotation

The axis of rotation for the geometry. 👑

SoSFVec3f SoVRMLBillboard::bboxCenter

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

SoSFVec3f SoVRMLBillboard::bboxSize

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

🦋 Author 🦋

Generated automatically by Doxygen for Coin from the source code.

ok that's literally the whole thing bestie, we ate and left no crumbs 💅✨ this page is from Coin, Version 3.1.3, and it lives at SoVRMLBillboard(3) — the date slot on that footer line is just vibing empty, iconic of it honestly 🎀💖

📦 where this page comes from