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. More...

#include <H3D/Billboard.h>

Inheritance diagram for H3D::Billboard:

Classes
class	SFMatrix4f
	Specialize the SFMatrix4f to update the matrix from the fields in the Billboard node. More...

Public Member Functions
	Billboard (Inst< AddChildren > _addChildren=0, Inst< RemoveChildren > _removeChildren=0, Inst< MFChild > _children=0, Inst< SFNode > _metadata=0, Inst< SFBound > _bound=0, Inst< SFVec3f > _bboxCenter=0, Inst< SFVec3f > _bboxSize=0, Inst< SFTransformedBound > _transformedBound=0, Inst< SFMatrix4f > _matrix=0, Inst< SFVec3f > _axisOfRotation=0)
	Constructor.

virtual void	traverseSG (TraverseInfo &ti)
	Set the matrix field in order to set the matrix field to perform the rotation required by the Billboard. More...

Public Member Functions inherited from H3D::MatrixTransform
	MatrixTransform (Inst< AddChildren > _addChildren=0, Inst< RemoveChildren > _removeChildren=0, Inst< MFChild > _children=0, Inst< SFNode > _metadata=0, Inst< SFBound > _bound=0, Inst< SFVec3f > _bboxCenter=0, Inst< SFVec3f > _bboxSize=0, Inst< SFTransformedBound > _transformedBound=0, Inst< SFMatrix4f > _matrix=0, Inst< SFMatrix4f > _accumulatedForward=0, Inst< SFMatrix4f > _accumulatedInverse=0)
	Constructor.

virtual void	render ()
	Render the children.

void	multiplyGLMatrix ()
	Multiply the currently active OpenGL matrix with the matrix of this node.

virtual bool	lineIntersect (const Vec3f &from, const Vec3f &to, LineIntersectResult &result)
	Detect intersection between a line segment and this Node. More...

virtual void	closestPoint (const Vec3f &p, NodeIntersectResult &result)
	Find closest point on Node to p. More...

virtual bool	movingSphereIntersect (H3DFloat radius, const Vec3f &from, const Vec3f &to, NodeIntersectResult &result)
	Detect collision between a moving sphere and the Node. More...

Public Member Functions inherited from H3D::X3DGroupingNode
	X3DGroupingNode (Inst< AddChildren > _addChildren=0, Inst< RemoveChildren > _removeChildren=0, Inst< MFChild > _children=0, Inst< SFNode > _metadata=0, Inst< SFBound > _bound=0, Inst< SFVec3f > _bboxCenter=0, Inst< SFVec3f > _bboxSize=0)
	Constructor.

virtual	~X3DGroupingNode ()
	Destructor.

virtual void	initialize ()
	Sets up the bound field using the bboxCenter and bboxSize fields. More...

Public Member Functions inherited from H3D::X3DChildNode
	X3DChildNode (Inst< SFNode > _metadata=0)
	Constructor.

Public Member Functions inherited from H3D::X3DNode
	X3DNode (Inst< SFNode > _metadata=0)
	Constructor.

X3DMetadataObject *	getMetadataByName (const string &_name)
	Given a name, the first X3DMetadataObject in the metadata field that matches that name is returned. More...

Public Member Functions inherited from H3D::Node
	Node ()
	Constructor.

virtual Node *	clone (bool deepCopy=true, DeepCopyMap *deepCopyMap=NULL)
	Returns a new instance of this node type with the same state as this one. More...

virtual	~Node ()
	Destructor.

X3DPrototypeInstance *	getProtoInstanceParent ()
	If this node is the root node in the proto body of a X3DPrototypeInstance then this will return that node. More...

void	setProtoInstanceParent (X3DPrototypeInstance *p)
	Set the X3DPrototypeInstance this node is the the root node if applicaple.

virtual string	defaultXMLContainerField ()
	Returns the default xml containerField attribute value. More...

virtual Field *	getField (const string &_name) const
	return a pointer to the field specified by name within this instance

int	addDestructCallback (void(func)(Node , void ), void args)
	Add a callback function to be run on destruction of node. More...

int	removeDestructCallback (void(func)(Node , void ), void args)
	Add a callback function to be run on destruction of node. More...

Public Member Functions inherited from H3D::H3DBoundedObject
	H3DBoundedObject (Inst< SFBound > _bound=0)
	Constructor.

Public Member Functions inherited from H3D::H3DDisplayListObject
	H3DDisplayListObject (Inst< DisplayList > _displayList=0)
	Constructor.

Public Attributes
H3DUniquePtr< SFVec3f >	axisOfRotation
	The axisOfRotation field specifies which axis to use to perform the rotation. More...

Public Attributes inherited from H3D::MatrixTransform
H3DUniquePtr< SFMatrix4f >	matrix
	The transformation matrix. More...

H3DUniquePtr< SFMatrix4f >	accumulatedForward
	The accumulated forward transform matrix, i.e. More...

H3DUniquePtr< SFMatrix4f >	accumulatedInverse
	The accumulated inverse transform matrix, i.e. More...

H3DUniquePtr< SFTransformedBound >	transformedBound
	This is the same as the bound field, but with the transformation applied to the bound. More...

Public Attributes inherited from H3D::X3DGroupingNode
bool	use_union_bound
	if true a route will be set up between the bound field of the nodes in children and the bound field of the grouping node. More...

H3DUniquePtr< AddChildren >	addChildren
	The addChildren event appends nodes to the children field of a grouping node. More...

H3DUniquePtr< RemoveChildren >	removeChildren
	The removeChildren event removes nodes from the children field of the grouping node . More...

H3DUniquePtr< MFChild >	children
	The nodes that are grouped together by this node. More...

Public Attributes inherited from H3D::X3DNode
H3DUniquePtr< SFNode >	metadata
	Meta data about the node. More...

Public Attributes inherited from H3D::X3DBoundedObject
H3DUniquePtr< SFVec3f >	bboxCenter
	Specifies a the center of an axis-aligned bounding box enclosing the node. More...

H3DUniquePtr< SFVec3f >	bboxSize
	Specifies a the size of an axis-aligned bounding box enclosing the node. More...

Public Attributes inherited from H3D::H3DBoundedObject
H3DUniquePtr< SFBound >	bound
	The field containing the bound object. More...

Public Attributes inherited from H3D::H3DDisplayListObject
H3DUniquePtr< DisplayList >	displayList
	The DisplayList instance handling the OpenGL caching of this object.

Static Public Attributes
static H3DNodeDatabase	database
	The H3DNodeDatabase for this node.

Static Public Attributes inherited from H3D::MatrixTransform
static H3DNodeDatabase	database
	The H3DNodeDatabase for this node.

Static Public Attributes inherited from H3D::X3DGroupingNode
static H3DNodeDatabase	database
	The H3DNodeDatabase for this node.

Static Public Attributes inherited from H3D::X3DNode
static H3DNodeDatabase	database
	The H3DNodeDatabase for this node.

Protected Attributes
H3DUniquePtr< SFVec3f >	vpPosition
	The position of the viewpoint in local coordinates of the Billboard node. More...

H3DUniquePtr< SFVec3f >	vpUp
	The up vector of the viewpoint in local coordinates of the Billboard node. More...

Protected Attributes inherited from H3D::X3DGroupingNode
bool	children_multi_pass_transparency
	Will be set in traverseSG to indicate if any of the children enables multi-pass transparency. More...

vector< H3DRenderStateObject * >	render_states
	A vector of all the H3DRenderStatesObject within this X3DGroupingNode.

vector< ClipPlane * >	clip_planes
	A vector of only ClipPlane children of this X3DGroupingNode.

Additional Inherited Members
Public Types inherited from H3D::Node
typedef std::map< Node , Node >	DeepCopyMap
	A map type used during a deep copy clone() to map from original nodes to cloned nodes.

Static Public Member Functions inherited from H3D::Node
static unsigned int	nrNodesAlive ()
	Returns the nr of nodes currently alive, i.e. nodes created but not destructed.

static int	nrNodesCreated ()
	Returns the number of nodes created in total since the start of the program.

Protected Member Functions inherited from H3D::Node
void	cloneFieldValue (Field &_from, Field &_to, bool deepCopy, DeepCopyMap &deepCopyMap)
	A helper function for the clone() method. More...

Static Protected Member Functions inherited from H3D::Node
static Node *	getClonedInstance (Node *original, bool deepCopy, DeepCopyMap &deepCopyMap)
	A helper function for nodes that implement clone() More...

Detailed Description

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:

Compute the vector from the Billboard node's origin to the viewer's position. This vector is called the billboard-to-viewer vector.
Compute the plane defined by the axisOfRotation and the billboard-to-viewer vector.
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:

Compute the billboard-to-viewer vector.
Rotate the Z-axis of the billboard to be collinear with the billboard-to-viewer vector and pointing towards the viewer's position.
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.

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.

Examples:

Billboard.x3d ( Source )

Internal routes:

Member Function Documentation

◆ traverseSG()

void Billboard::traverseSG ( TraverseInfo & ti )

virtual

Set the matrix field in order to set the matrix field to perform the rotation required by the Billboard.

Parameters

ti	The TraverseInfo object containing information about the traversal.

Reimplemented from H3D::MatrixTransform.

References H3D::X3DViewpointNode::accForwardMatrix, H3D::TraverseInfo::getAccInverseMatrix(), H3D::X3DViewpointNode::getActive(), H3D::X3DViewpointNode::totalOrientation, H3D::X3DViewpointNode::totalPosition, H3D::MatrixTransform::traverseSG(), vpPosition, and vpUp.

Member Data Documentation

◆ axisOfRotation

H3DUniquePtr< SFVec3f > H3D::Billboard::axisOfRotation

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 set to (0, 0, 0), the special case of viewer-alignment is indicated.

Access type: inputOutput
Default value: Vec3f( 0, 1, 0 )

Referenced by Billboard().

◆ vpPosition

H3DUniquePtr< SFVec3f > H3D::Billboard::vpPosition

protected

The position of the viewpoint in local coordinates of the Billboard node.

This field will be set in traverseSG(). C++ only field

Referenced by Billboard(), and traverseSG().

◆ vpUp

H3DUniquePtr< SFVec3f > H3D::Billboard::vpUp

protected

The up vector of the viewpoint in local coordinates of the Billboard node.

This field will be set in traverseSG(). C++ only field

Referenced by Billboard(), and traverseSG().

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

Classes

Public Member Functions

Public Attributes

Static Public Attributes

Protected Attributes