Ogre::BillboardSet Class Reference

A collection of billboards (faces which are always facing the given direction) with the same (default) dimensions, material and which are fairly close proximity to each other. More...

#include <OgreBillboardSet.h>

Inheritance diagram for Ogre::BillboardSet:

[legend]

List of all members.

Public Types
typedef std::vector < ShadowRenderable * >	ShadowRenderableList
typedef VectorIterator < ShadowRenderableList >	ShadowRenderableListIterator
Public Member Functions
	BillboardSet (const String &name, unsigned int poolSize=20, bool externalDataSource=false)
	Usual constructor - this is called by the SceneManager.
virtual	~BillboardSet ()
Billboard *	createBillboard (const Vector3 &position, const ColourValue &colour=ColourValue::White)
	Creates a new billboard and adds it to this set.
Billboard *	createBillboard (Real x, Real y, Real z, const ColourValue &colour=ColourValue::White)
	Creates a new billboard and adds it to this set.
virtual int	getNumBillboards (void) const
	Returns the number of active billboards which currently make up this set.
virtual void	setAutoextend (bool autoextend)
	Tells the set whether to allow automatic extension of the pool of billboards.
virtual bool	getAutoextend (void) const
	Returns true if the billboard pool automatically extends.
virtual void	setSortingEnabled (bool sortenable)
	Enables sorting for this BillboardSet.
virtual bool	getSortingEnabled (void) const
	Returns true if sorting of billboards is enabled based on their distance from the camera.
virtual void	setPoolSize (size_t size)
	Adjusts the size of the pool of billboards available in this set.
virtual unsigned int	getPoolSize (void) const
	Returns the current size of the billboard pool.
virtual void	clear ()
	Empties this set of all billboards.
virtual Billboard *	getBillboard (unsigned int index) const
	Returns a pointer to the billboard at the supplied index.
virtual void	removeBillboard (unsigned int index)
	Removes the billboard at the supplied index.
virtual void	removeBillboard (Billboard *pBill)
	Removes a billboard from the set.
virtual void	setBillboardOrigin (BillboardOrigin origin)
	Sets the point which acts as the origin point for all billboards in this set.
virtual BillboardOrigin	getBillboardOrigin (void) const
	Gets the point which acts as the origin point for all billboards in this set.
virtual void	setBillboardRotationType (BillboardRotationType rotationType)
	Sets billboard rotation type.
virtual BillboardRotationType	getBillboardRotationType (void) const
	Sets billboard rotation type.
virtual void	setDefaultDimensions (Real width, Real height)
	Sets the default dimensions of the billboards in this set.
virtual void	setDefaultWidth (Real width)
	See setDefaultDimensions - this sets 1 component individually.
virtual Real	getDefaultWidth (void) const
	See setDefaultDimensions - this gets 1 component individually.
virtual void	setDefaultHeight (Real height)
	See setDefaultDimensions - this sets 1 component individually.
virtual Real	getDefaultHeight (void) const
	See setDefaultDimensions - this gets 1 component individually.
virtual void	setMaterialName (const String &name)
	Sets the name of the material to be used for this billboard set.
virtual const String &	getMaterialName (void) const
	Sets the name of the material to be used for this billboard set.
virtual void	_notifyCurrentCamera (Camera *cam)
	Overridden from MovableObject.
void	beginBillboards (size_t numBillboards=0)
	Begin injection of billboard data; applicable when constructing the BillboardSet for external data use.
void	injectBillboard (const Billboard &bb)
	Define a billboard.
void	endBillboards (void)
	Finish defining billboards.
void	setBounds (const AxisAlignedBox &box, Real radius)
	Set the bounds of the BillboardSet.
virtual const AxisAlignedBox &	getBoundingBox (void) const
	Overridden from MovableObject.
virtual Real	getBoundingRadius (void) const
	Overridden from MovableObject.
virtual void	_updateRenderQueue (RenderQueue *queue)
	Overridden from MovableObject.
virtual const MaterialPtr &	getMaterial (void) const
	Overridden from MovableObject.
virtual void	getRenderOperation (RenderOperation &op)
	Overridden from MovableObject.
virtual void	getWorldTransforms (Matrix4 *xform) const
	Overridden from MovableObject.
virtual void	_notifyBillboardResized (void)
	Internal callback used by Billboards to notify their parent that they have been resized.
virtual void	_notifyBillboardRotated (void)
	Internal callback used by Billboards to notify their parent that they have been rotated.
virtual bool	getCullIndividually (void) const
	Returns whether or not billboards in this are tested individually for culling.
virtual void	setCullIndividually (bool cullIndividual)
	Sets whether culling tests billboards in this individually as well as in a group.
virtual void	setBillboardType (BillboardType bbt)
	Sets the type of billboard to render.
virtual BillboardType	getBillboardType (void) const
	Returns the billboard type in use.
virtual void	setCommonDirection (const Vector3 &vec)
	Use this to specify the common direction given to billboards of type BBT_ORIENTED_COMMON or BBT_PERPENDICULAR_COMMON.
virtual const Vector3 &	getCommonDirection (void) const
	Gets the common direction for all billboards (BBT_ORIENTED_COMMON).
virtual void	setCommonUpVector (const Vector3 &vec)
	Use this to specify the common up-vector given to billboards of type BBT_PERPENDICULAR_SELF or BBT_PERPENDICULAR_COMMON.
virtual const Vector3 &	getCommonUpVector (void) const
	Gets the common up-vector for all billboards (BBT_PERPENDICULAR_SELF and BBT_PERPENDICULAR_COMMON).
virtual void	setUseAccurateFacing (bool acc)
	Sets whether or not billboards should use an 'accurate' facing model based on the vector from each billboard to the camera, rather than an optimised version using just the camera direction.
virtual bool	getUseAccurateFacing (void) const
	Gets whether or not billboards use an 'accurate' facing model based on the vector from each billboard to the camera, rather than an optimised version using just the camera direction.
virtual const String &	getMovableType (void) const
	Overridden from MovableObject.
Real	getSquaredViewDepth (const Camera *cam) const
	Overridden, see Renderable.
virtual void	_updateBounds (void)
	Update the bounds of the billboardset.
const LightList &	getLights (void) const
	Gets a list of lights, ordered relative to how close they are to this renderable. Remarks: Directional lights, which have no position, will always be first on this list.
void	visitRenderables (Renderable::Visitor *visitor, bool debugRenderables=false)
	Method to allow a caller to abstractly iterate over the Renderable instances that this MovableObject will add to the render queue when asked, if any. Parameters: visitor  Pointer to a class implementing the Renderable::Visitor interface which will be called back for each Renderable which will be queued. Bear in mind that the state of the Renderable instances may not be finalised depending on when you call this. debugRenderables  If false, only regular renderables will be visited (those for normal display). If true, debug renderables will be included too.
virtual void	_sortBillboards (Camera *cam)
	Sort the billboard set.
virtual SortMode	_getSortMode (void) const
	Gets the sort mode of this billboard set.
virtual void	setBillboardsInWorldSpace (bool ws)
	Sets whether billboards should be treated as being in world space.
virtual void	setTextureCoords (Ogre::FloatRect const *coords, uint16 numCoords)
	BillboardSet can use custom texture coordinates for various billboards.
virtual void	setTextureStacksAndSlices (uchar stacks, uchar slices)
	setTextureStacksAndSlices() will generate texture coordinate rects as if the texture for the billboard set contained 'stacks' rows of 'slices' images each, all equal size.
virtual Ogre::FloatRect const *	getTextureCoords (uint16 *oNumCoords)
	getTextureCoords() returns the current texture coordinate rects in effect.
virtual void	setPointRenderingEnabled (bool enabled)
	Set whether or not the BillboardSet will use point rendering rather than manually generated quads.
virtual bool	isPointRenderingEnabled (void) const
	Returns whether point rendering is enabled.
uint32	getTypeFlags (void) const
	Override to return specific type flag.
virtual void	_notifyCreator (MovableObjectFactory *fact)
	Notify the object of it's creator (internal use only).
virtual MovableObjectFactory *	_getCreator (void) const
	Get the creator of this object, if any (internal use only).
virtual void	_notifyManager (SceneManager *man)
	Notify the object of it's manager (internal use only).
virtual SceneManager *	_getManager (void) const
	Get the manager of this object, if any (internal use only).
virtual const String &	getName (void) const
	Returns the name of this object.
virtual Node *	getParentNode (void) const
	Returns the node to which this object is attached.
virtual SceneNode *	getParentSceneNode (void) const
	Returns the scene node to which this object is attached.
virtual void	_notifyAttached (Node *parent, bool isTagPoint=false)
	Internal method called to notify the object that it has been attached to a node.
virtual bool	isAttached (void) const
	Returns true if this object is attached to a SceneNode or TagPoint.
virtual void	detatchFromParent (void)
	Detaches an object from a parent SceneNode or TagPoint, if attached.
virtual bool	isInScene (void) const
	Returns true if this object is attached to a SceneNode or TagPoint, and this SceneNode / TagPoint is currently in an active part of the scene graph.
virtual void	_notifyMoved (void)
	Internal method called to notify the object that it has been moved.
virtual const AxisAlignedBox &	getWorldBoundingBox (bool derive=false) const
	Retrieves the axis-aligned bounding box for this object in world coordinates.
virtual const Sphere &	getWorldBoundingSphere (bool derive=false) const
	Retrieves the worldspace bounding sphere for this object.
virtual void	setVisible (bool visible)
	Tells this object whether to be visible or not, if it has a renderable component.
virtual bool	getVisible (void) const
	Gets this object whether to be visible or not, if it has a renderable component.
virtual bool	isVisible (void) const
	Returns whether or not this object is supposed to be visible or not.
virtual void	setRenderingDistance (Real dist)
	Sets the distance at which the object is no longer rendered.
virtual Real	getRenderingDistance (void) const
	Gets the distance at which batches are no longer rendered.
virtual void	setUserObject (UserDefinedObject *obj)
	Call this to associate your own custom user object instance with this MovableObject.
virtual UserDefinedObject *	getUserObject (void)
	Retrieves a pointer to a custom application object associated with this movable by an earlier call to setUserObject.
virtual void	setUserAny (const Any &anything)
	Sets any kind of user value on this object.
virtual const Any &	getUserAny (void) const
	Retrieves the custom user value associated with this object.
virtual void	setRenderQueueGroup (uint8 queueID)
	Sets the render queue group this entity will be rendered through.
virtual uint8	getRenderQueueGroup (void) const
	Gets the queue group for this entity, see setRenderQueueGroup for full details.
virtual const Matrix4 &	_getParentNodeFullTransform (void) const
	return the full transformation of the parent sceneNode or the attachingPoint node
virtual void	setQueryFlags (uint32 flags)
	Sets the query flags for this object.
virtual void	addQueryFlags (uint32 flags)
	As setQueryFlags, except the flags passed as parameters are appended to the existing flags on this object.
virtual void	removeQueryFlags (unsigned long flags)
	As setQueryFlags, except the flags passed as parameters are removed from the existing flags on this object.
virtual uint32	getQueryFlags (void) const
	Returns the query flags relevant for this object.
virtual void	setVisibilityFlags (uint32 flags)
	Sets the visiblity flags for this object.
virtual void	addVisibilityFlags (uint32 flags)
	As setVisibilityFlags, except the flags passed as parameters are appended to the existing flags on this object.
virtual void	removeVisibilityFlags (uint32 flags)
	As setVisibilityFlags, except the flags passed as parameters are removed from the existing flags on this object.
virtual uint32	getVisibilityFlags (void) const
	Returns the visibility flags relevant for this object.
virtual void	setListener (Listener *listener)
	Sets a listener for this object.
virtual Listener *	getListener (void) const
	Gets the current listener for this object.
virtual const LightList &	queryLights (void) const
	Gets a list of lights, ordered relative to how close they are to this movable object.
virtual LightList *	_getLightList ()
	Returns a pointer to the current list of lights for this object.
EdgeData *	getEdgeList (void)
	Define a default implementation of method from ShadowCaster which implements no shadows.
bool	hasEdgeList (void)
	Define a default implementation of method from ShadowCaster which implements no shadows.
ShadowRenderableListIterator	getShadowVolumeRenderableIterator (ShadowTechnique shadowTechnique, const Light *light, HardwareIndexBufferSharedPtr *indexBuffer, bool extrudeVertices, Real extrusionDist, unsigned long flags=0)
	Define a default implementation of method from ShadowCaster which implements no shadows.
const AxisAlignedBox &	getLightCapBounds (void) const
	Overridden member from ShadowCaster.
const AxisAlignedBox &	getDarkCapBounds (const Light &light, Real dirLightExtrusionDist) const
	Overridden member from ShadowCaster.
void	setCastShadows (bool enabled)
	Sets whether or not this object will cast shadows.
bool	getCastShadows (void) const
	Returns whether shadow casting is enabled for this object.
Real	getPointExtrusionDistance (const Light *l) const
	Get the distance to extrude for a point/spot light.
virtual void	setDebugDisplayEnabled (bool enabled)
	Sets whether or not the debug display of this object is enabled.
virtual bool	isDebugDisplayEnabled (void) const
	Gets whether debug display of this object is enabled.
const StringVector &	getAnimableValueNames (void) const
	Gets a list of animable value names for this object.
virtual AnimableValuePtr	createAnimableValue (const String &valueName)
	Create a reference-counted AnimableValuePtr for the named value.
void *	operator new (size_t sz, const char *file, int line, const char *func)
	operator new, with debug line info
void *	operator new (size_t sz)
void *	operator new (size_t sz, void *ptr)
	placement operator new
void *	operator new[] (size_t sz, const char *file, int line, const char *func)
	array operator new, with debug line info
void *	operator new[] (size_t sz)
void	operator delete (void *ptr)
void	operator delete (void *ptr, const char *, int, const char *)
void	operator delete[] (void *ptr)
void	operator delete[] (void *ptr, const char *, int, const char *)
virtual Technique *	getTechnique (void) const
	Retrieves a pointer to the Material Technique this renderable object uses.
virtual bool	preRender (SceneManager *sm, RenderSystem *rsys)
	Called just prior to the Renderable being rendered.
virtual void	postRender (SceneManager *sm, RenderSystem *rsys)
	Called immediately after the Renderable has been rendered.
virtual unsigned short	getNumWorldTransforms (void) const
	Returns the number of world transform matrices this renderable requires.
void	setUseIdentityProjection (bool useIdentityProjection)
	Sets whether or not to use an 'identity' projection.
bool	getUseIdentityProjection (void) const
	Returns whether or not to use an 'identity' projection.
void	setUseIdentityView (bool useIdentityView)
	Sets whether or not to use an 'identity' view.
bool	getUseIdentityView (void) const
	Returns whether or not to use an 'identity' view.
virtual bool	getCastsShadows (void) const
	Method which reports whether this renderable would normally cast a shadow.
void	setCustomParameter (size_t index, const Vector4 &value)
	Sets a custom parameter for this Renderable, which may be used to drive calculations for this specific Renderable, like GPU program parameters.
const Vector4 &	getCustomParameter (size_t index) const
	Gets the custom value associated with this Renderable at the given index.
virtual void	_updateCustomGpuParameter (const GpuProgramParameters::AutoConstantEntry &constantEntry, GpuProgramParameters *params) const
	Update a custom GpuProgramParameters constant which is derived from information only this Renderable knows.
virtual void	setPolygonModeOverrideable (bool override)
	Sets whether this renderable's chosen detail level can be overridden (downgraded) by the camera setting.
virtual bool	getPolygonModeOverrideable (void) const
	Gets whether this renderable's chosen detail level can be overridden (downgraded) by the camera setting.
virtual void	setUserAny (const Any &anything)
	Sets any kind of user value on this object.
virtual const Any &	getUserAny (void) const
	Retrieves the custom user value associated with this object.
virtual RenderSystemData *	getRenderSystemData () const
	Sets render system private data.
virtual void	setRenderSystemData (RenderSystemData *val) const
	gets render system private data
Static Public Member Functions
static void	setDefaultQueryFlags (uint32 flags)
	Set the default query flags for all future MovableObject instances.
static uint32	getDefaultQueryFlags ()
	Get the default query flags for all future MovableObject instances.
static void	setDefaultVisibilityFlags (uint32 flags)
	Set the default visibility flags for all future MovableObject instances.
static uint32	getDefaultVisibilityFlags ()
	Get the default visibility flags for all future MovableObject instances.
static void	extrudeVertices (const HardwareVertexBufferSharedPtr &vertexBuffer, size_t originalVertexCount, const Vector4 &lightPos, Real extrudeDist)
	Utility method for extruding vertices based on a light.
Protected Types
typedef std::list < Billboard * >	ActiveBillboardList
typedef std::list < Billboard * >	FreeBillboardList
typedef std::vector < Billboard * >	BillboardPool
typedef std::vector < Ogre::FloatRect >	TextureCoordSets
typedef std::map < String, StringVector >	AnimableDictionaryMap
typedef std::map < size_t, Vector4 >	CustomParameterMap
Protected Member Functions
	BillboardSet ()
	Private constructor (instances cannot be created directly).
bool	billboardVisible (Camera *cam, const Billboard &bill)
	Internal method for culling individual billboards.
virtual void	increasePool (size_t size)
	Internal method for increasing pool size.
void	genBillboardAxes (Vector3 *pX, Vector3 *pY, const Billboard *pBill=0)
	Internal method for generating billboard corners.
void	getParametricOffsets (Real &left, Real &right, Real &top, Real &bottom)
	Internal method, generates parametric offsets based on origin.
void	genVertices (const Vector3 *const offsets, const Billboard &pBillboard)
	Internal method for generating vertex data.
void	genVertOffsets (Real inleft, Real inright, Real intop, Real inbottom, Real width, Real height, const Vector3 &x, const Vector3 &y, Vector3 *pDestVec)
	Internal method generates vertex offsets.
Real	getExtrusionDistance (const Vector3 &objectPos, const Light *light) const
	Helper method for calculating extrusion distance.
virtual void	updateEdgeListLightFacing (EdgeData *edgeData, const Vector4 &lightPos)
	Tells the caster to perform the tasks necessary to update the edge data's light listing.
virtual void	generateShadowVolume (EdgeData *edgeData, const HardwareIndexBufferSharedPtr &indexBuffer, const Light *light, ShadowRenderableList &shadowRenderables, unsigned long flags)
	Generates the indexes required to render a shadow volume into the index buffer which is passed in, and updates shadow renderables to use it.
virtual void	extrudeBounds (AxisAlignedBox &box, const Vector4 &lightPos, Real extrudeDist) const
	Utility method for extruding a bounding box.
virtual const String &	getAnimableDictionaryName (void) const
	Get the name of the animable dictionary for this class.
void	createAnimableDictionary (void) const
	Internal method for creating a dictionary of animable value names for the class, if it does not already exist.
StringVector &	_getAnimableValueNames (void)
	Get an updateable reference to animable value list.
virtual void	initialiseAnimableDictionary (StringVector &) const
	Internal method for initialising dictionary; should be implemented by subclasses wanting to expose animable parameters.
Protected Attributes
AxisAlignedBox	mAABB
	Bounds of all billboards in this set.
Real	mBoundingRadius
	Bounding radius.
BillboardOrigin	mOriginType
	Origin of each billboard.
BillboardRotationType	mRotationType
	Rotation type of each billboard.
Real	mDefaultWidth
	Default width of each billboard.
Real	mDefaultHeight
	Default height of each billboard.
String	mMaterialName
	Name of the material to use.
MaterialPtr	mpMaterial
	Pointer to the material to use.
bool	mAllDefaultSize
	True if no billboards in this set have been resized - greater efficiency.
bool	mAutoExtendPool
	Flag indicating whether to autoextend pool.
bool	mSortingEnabled
	Flag indicating whether the billboards has to be sorted.
bool	mAccurateFacing
bool	mAllDefaultRotation
bool	mWorldSpace
ActiveBillboardList	mActiveBillboards
	Active billboard list.
FreeBillboardList	mFreeBillboards
	Free billboard queue.
BillboardPool	mBillboardPool
	Pool of billboard instances for use and reuse in the active billboard list.
VertexData *	mVertexData
	The vertex position data for all billboards in this set.
HardwareVertexBufferSharedPtr	mMainBuf
	Shortcut to main buffer (positions, colours, texture coords).
float *	mLockPtr
	Locked pointer to buffer.
Vector3	mVOffset [4]
	Boundary offsets based on origin and camera orientation Vector3 vLeftOff, vRightOff, vTopOff, vBottomOff; Final vertex offsets, used where sizes all default to save calcs.
Camera *	mCurrentCamera
	Current camera.
Real	mLeftOff
Real	mRightOff
Real	mTopOff
Real	mBottomOff
Vector3	mCamX
Vector3	mCamY
Vector3	mCamDir
Quaternion	mCamQ
Vector3	mCamPos
IndexData *	mIndexData
	The vertex index data for all billboards in this set (1 set only).
bool	mCullIndividual
	Flag indicating whether each billboard should be culled separately (default: false).
TextureCoordSets	mTextureCoords
BillboardType	mBillboardType
	The type of billboard to render.
Vector3	mCommonDirection
	Common direction for billboards of type BBT_ORIENTED_COMMON and BBT_PERPENDICULAR_COMMON.
Vector3	mCommonUpVector
	Common up-vector for billboards of type BBT_PERPENDICULAR_SELF and BBT_PERPENDICULAR_COMMON.
unsigned short	mNumVisibleBillboards
bool	mPointRendering
	Use point rendering?
String	mName
	Name of this object.
MovableObjectFactory *	mCreator
	Creator of this object (if created by a factory).
SceneManager *	mManager
	SceneManager holding this object (if applicable).
Node *	mParentNode
	node to which this object is attached
bool	mParentIsTagPoint
bool	mVisible
	Is this object visible?
bool	mDebugDisplay
	Is debug display enabled?
Real	mUpperDistance
	Upper distance to still render.
Real	mSquaredUpperDistance
bool	mBeyondFarDistance
	Hidden because of distance?
Any	mUserAny
	User defined link to another object / value / whatever.
uint8	mRenderQueueID
	The render queue to use when rendering this object.
bool	mRenderQueueIDSet
	Flags whether the RenderQueue's default should be used.
uint32	mQueryFlags
	Flags determining whether this object is included / excluded from scene queries.
uint32	mVisibilityFlags
	Flags determining whether this object is visible (compared to SceneManager mask).
AxisAlignedBox	mWorldAABB
	Cached world AABB of this object.
Sphere	mWorldBoundingSphere
AxisAlignedBox	mWorldDarkCapBounds
	World space AABB of this object's dark cap.
bool	mCastShadows
	Does this object cast shadows?
bool	mRenderingDisabled
	Does rendering this object disabled by listener?
Listener *	mListener
	MovableObject listener - only one allowed (no list) for size & performance reasons. */.
LightList	mLightList
	List of lights for this object.
ulong	mLightListUpdated
	The last frame that this light list was updated in.
CustomParameterMap	mCustomParameters
bool	mPolygonModeOverrideable
bool	mUseIdentityProjection
bool	mUseIdentityView
Any	mUserAny
RenderSystemData *	mRenderSystemData
Static Protected Attributes
static RadixSort < ActiveBillboardList, Billboard *, float >	mRadixSorter
static uint32	msDefaultQueryFlags
	Default query flags.
static uint32	msDefaultVisibilityFlags
	Default visibility flags.
static AnimableDictionaryMap	msAnimableDictionary
	Static map of class name to list of animable value names.
Private Member Functions
void	_createBuffers (void)
	Internal method creates vertex and index buffers.
void	_destroyBuffers (void)
	Internal method destroys vertex and index buffers.
Private Attributes
bool	mBuffersCreated
	Flag indicating whether the HW buffers have been created.
size_t	mPoolSize
	The number of billboard in the pool.
bool	mExternalData
	Is external billboard data in use?
Classes
struct	SortByDirectionFunctor
	Sort by direction functor. More...
struct	SortByDistanceFunctor
	Sort by distance functor. More...

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Detailed Description

A collection of billboards (faces which are always facing the given direction) with the same (default) dimensions, material and which are fairly close proximity to each other.

Remarks:

Billboards are rectangles made up of 2 tris which are always facing the given direction. They are typically used for special effects like particles. This class collects together a set of billboards with the same (default) dimensions, material and relative locality in order to process them more efficiently. The entire set of billboards will be culled as a whole (by default, although this can be changed if you want a large set of billboards which are spread out and you want them culled individually), individual Billboards have locations which are relative to the set (which itself derives it's position from the SceneNode it is attached to since it is a MoveableObject), they will be rendered as a single rendering operation, and some calculations will be sped up by the fact that they use the same dimensions so some workings can be reused.

A BillboardSet can be created using the SceneManager::createBillboardSet method. They can also be used internally by other classes to create effects.

Note:

Billboard bounds are only automatically calculated when you create them. If you modify the position of a billboard you may need to call _updateBounds if the billboard moves outside the original bounds. Similarly, the bounds do no shrink when you remove a billboard, if you want them to call _updateBounds, but note this requires a potentially expensi