The SoVRMLLOD class is used to represent various levels of detail based on distance.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: More...

#include <Inventor/VRMLnodes/SoVRMLLOD.h>

Inheritance diagram for SoVRMLLOD:

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 run-time type checking and "downward" casting. More...

	SoVRMLLOD (void)

	SoVRMLLOD (int levels)

virtual SbBool	affectsState (void) const

void	addLevel (SoNode *level)

void	insertLevel (SoNode *level, int idx)

SoNode *	getLevel (int idx) const

int	findLevel (const SoNode *level) const

int	getNumLevels (void) const

void	removeLevel (int idx)

void	removeLevel (SoNode *level)

void	removeAllLevels (void)

void	replaceLevel (int idx, SoNode *level)

void	replaceLevel (SoNode old, SoNode level)

virtual void	doAction (SoAction *action)

virtual void	callback (SoCallbackAction *action)

virtual void	GLRender (SoGLRenderAction *action)

virtual void	rayPick (SoRayPickAction *action)

virtual void	getBoundingBox (SoGetBoundingBoxAction *action)

virtual void	search (SoSearchAction *action)

virtual void	write (SoWriteAction *action)

virtual void	getPrimitiveCount (SoGetPrimitiveCountAction *action)

virtual void	audioRender (SoAudioRenderAction *action)

virtual void	GLRenderBelowPath (SoGLRenderAction *action)

virtual void	GLRenderInPath (SoGLRenderAction *action)

virtual void	GLRenderOffPath (SoGLRenderAction *action)

void	addChild (SoNode *child)

void	insertChild (SoNode *child, int idx)

SoNode *	getChild (int idx) const

int	findChild (const SoNode *child) const

int	getNumChildren (void) const

void	removeChild (int idx)

void	removeChild (SoNode *child)

void	removeAllChildren (void)

void	replaceChild (int idx, SoNode *child)

void	replaceChild (SoNode old, SoNode child)

virtual SoChildList *	getChildren (void) const

Public Member Functions inherited from SoGroup
	SoGroup (void)

	SoGroup (int nchildren)

virtual void	getMatrix (SoGetMatrixAction *action)

virtual void	handleEvent (SoHandleEventAction *action)

virtual void	pick (SoPickAction *action)

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 SoNode *	copy (SbBool copyconnections=FALSE) const

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
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

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 SoAuditorList &	getAuditors (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 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 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
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 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)

Public Attributes
SoMFFloat	range

SoSFVec3f	center

SoMFNode	level

Protected Member Functions
virtual const SoFieldData *	getFieldData (void) const

virtual	~SoVRMLLOD ()

virtual void	notify (SoNotList *list)

virtual SbBool	readInstance (SoInput *in, unsigned short flags)

virtual void	copyContents (const SoFieldContainer *from, SbBool copyConn)

virtual int	whichToTraverse (SoAction *action)

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 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 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

Detailed Description

The SoVRMLLOD class is used to represent various levels of detail based on distance.

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:

LOD {
  exposedField MFNode  level    []
  field        SFVec3f center   0 0 0    # (-,)
  field        MFFloat range    []       # (0,)
}

The LOD node specifies various levels of detail or complexity for a given object, and provides hints allowing browsers to automatically choose the appropriate version of the object based on the distance from the user. The level field contains a list of nodes that represent the same object or objects at varying levels of detail, ordered from highest level of detail to the lowest level of detail. The range field specifies the ideal distances at which to switch between the levels. 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), contains details on the types of nodes that are legal values for level.

The center field is a translation offset in the local coordinate system that specifies the centre of the LOD node for distance calculations.

The number of nodes in the level field shall exceed the number of values in the range field by one (i.e., N+1 level values for N range values). The range field contains monotonic increasing values that shall be greater than zero. In order to calculate which level to display, first the distance is calculated from the viewer's location, transformed into the local coordinate system of the LOD node (including any scaling transformations), to the center point of the LOD node. Then, the LOD node evaluates the step function L(d) to choose a level for a given value of d (where d is the distance from the viewer position to the centre of the LOD node). Let n ranges, R0, R1, R2, ..., Rn-1, partition the domain (0, +infinity) into n+1 subintervals given by (0, R0), [R0, R1)... , [Rn-1, +infinity). Also, let n levels L0, L1, L2, ..., Ln-1 be the values of the step function function L(d). The level node, L(d), for a given distance d is defined as follows:

  L(d) = L0,   if d < R0,
       = Li+1, if Ri <= d < Ri+1, for -1 < i < n-1,
       = Ln-1, if d >= Rn-1.

Specifying too few levels will result in the last level being used repeatedly for the lowest levels of detail. If more levels than ranges are specified, the extra levels are ignored. An empty range field is an exception to this rule. This case is a hint to the browser that it may choose a level automatically to maintain a constant display rate. Each value in the range field shall be greater than the previous value.

LOD nodes are evaluated top-down in the scene graph. Only the descendants of the currently selected level are rendered. All nodes under an LOD node continue to receive and send events regardless of which LOD node's level is active. For example, if an active TimeSensor node is contained within an inactive level of an LOD node, the TimeSensor node sends events regardless of the LOD node's state.

Constructor & Destructor Documentation

SoVRMLLOD::SoVRMLLOD ( void )

Constructor.

SoVRMLLOD::SoVRMLLOD ( int levels )

Constructor. levels is the expected number of levels.

SoVRMLLOD::~SoVRMLLOD ( )

protectedvirtual

Destructor.

Member Function Documentation

SoType SoVRMLLOD::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 SoGroup.

const SoFieldData * SoVRMLLOD::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 SoGroup.

SbBool SoVRMLLOD::affectsState ( void ) const

virtual

Returns TRUE if the node could have any effect on the state during traversal.

If it returns FALSE, no data in the traversal-state will change from the pre-traversal state to the post-traversal state. The SoSeparator node will for instance return FALSE, as it pushes and pops the state before and after traversal of its children. All SoShape nodes will also return FALSE, as just pushing out geometry data to the rendering engine won't affect the actual rendering state.

The default method returns TRUE, on a "better safe than sorry" philosophy.

Reimplemented from SoNode.

void SoVRMLLOD::addLevel ( SoNode * levelptr )

Adds a new level.

void SoVRMLLOD::insertLevel	(	SoNode *	levelptr,
		int	idx
	)

Inserts a new level.

SoNode * SoVRMLLOD::getLevel ( int idx ) const

Returns a level.

int SoVRMLLOD::findLevel ( const SoNode * node ) const

Find node, and return the level index or -1 if not found.

int SoVRMLLOD::getNumLevels ( void ) const

Return the number of levels.

void SoVRMLLOD::removeLevel ( int idx )

Removes the level at index idx.

void SoVRMLLOD::removeLevel ( SoNode * levelptr )

Find level, and remove it if found.

void SoVRMLLOD::removeAllLevels ( void )

Remove all levels.

void SoVRMLLOD::replaceLevel	(	int	idx,
		SoNode *	node
	)

Replace the level at idx with node.

void SoVRMLLOD::replaceLevel	(	SoNode *	oldnode,
		SoNode *	newnode
	)

Find oldnode, and replace it with newnode.

void SoVRMLLOD::doAction ( SoAction * action )

virtual

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

Reimplemented from SoGroup.

void SoVRMLLOD::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 SoVRMLLOD::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 SoVRMLLOD::rayPick ( SoRayPickAction * action )

virtual

Action method for SoRayPickAction.

Checks the ray specification of the action and tests for intersection with the data of the node.

Nodes influencing relevant state variables for how picking is done also overrides this method.

Reimplemented from SoNode.

void SoVRMLLOD::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 SoVRMLLOD::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 SoGroup.

void SoVRMLLOD::write ( SoWriteAction * action )

virtual

Action method for SoWriteAction.

Writes out a node object, and any connected nodes, engines etc, if necessary.

Reimplemented from SoGroup.

void SoVRMLLOD::getPrimitiveCount ( SoGetPrimitiveCountAction * action )

virtual

Action method for the SoGetPrimitiveCountAction.

Calculates the number of triangle, line segment and point primitives for the node and adds these to the counters of the action.

Nodes influencing how geometry nodes calculates their primitive count also overrides this method to change the relevant state variables.

Reimplemented from SoGroup.

void SoVRMLLOD::audioRender ( SoAudioRenderAction * action )

virtual

Action method for SoAudioRenderAction.

Does common processing for SoAudioRenderAction action instances.

Reimplemented from SoGroup.

void SoVRMLLOD::GLRenderBelowPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

void SoVRMLLOD::GLRenderInPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

void SoVRMLLOD::GLRenderOffPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

void SoVRMLLOD::addChild ( SoNode * node )

virtual

Append a child node to the list of children nodes this group node is managing.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::insertChild	(	SoNode *	child,
		int	newchildindex
	)

virtual

Insert a child node at position newchildindex.

newchildindex must be <= this->getNumChildren()

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

SoNode * SoVRMLLOD::getChild ( int index ) const

virtual

Returns pointer to child node at index.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

int SoVRMLLOD::findChild ( const SoNode * node ) const

virtual

Returns index in our list of children for child node, or -1 if node is not a child of this group node.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

int SoVRMLLOD::getNumChildren ( void ) const

virtual

Returns number of child nodes managed by this group.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::removeChild ( int childindex )

virtual

Remove node at childindex in our list of children.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::removeChild ( SoNode * child )

virtual

Remove child from the set of children managed by this group node. Will decrease the reference count of child by 1.

This is a convenience method. It will simply call findChild() with child as argument, and then call removeChild(int) if the child is found.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::removeAllChildren ( void )

virtual

Do not manage the children anymore. Will dereference all children by 1 as they are removed.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::replaceChild	(	int	index,
		SoNode *	newchild
	)

virtual

Replace child at index with newChild.

Dereferences the child previously at index, and increases the reference count of newChild by 1.

index must be < this->getNumChildren()

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

void SoVRMLLOD::replaceChild	(	SoNode *	oldchild,
		SoNode *	newchild
	)

virtual

Replace oldchild with newchild.

Dereferences oldchild by 1, and increases the reference count of newchild by 1.

This is a convenience method. It will simply call findChild() with oldchild as argument, and call replaceChild(int, SoNode*) if the child is found.

Please note that this method is not virtual in the original SGI Inventor API.

Reimplemented from SoGroup.

SoChildList * SoVRMLLOD::getChildren ( void ) const

virtual

Returns list of children.

Reimplemented from SoGroup.

void SoVRMLLOD::notify ( SoNotList * l )

protectedvirtual

Notifies all auditors for this instance when changes are made.

Reimplemented from SoNode.

SbBool SoVRMLLOD::readInstance	(	SoInput *	in,
		unsigned short	flags
	)

protectedvirtual

This method is mainly intended for internal use during file import operations.

It reads a definition of an instance from the input stream in. The input stream state points to the start of a serialized / persistant representation of an instance of this class type.

TRUE or FALSE is returned, depending on if the instantiation and configuration of the new object of this class type went ok or not. The import process should be robust and handle corrupted input streams by returning FALSE.

flags is used internally during binary import when reading user extension nodes, group nodes or engines.

Reimplemented from SoGroup.

void SoVRMLLOD::copyContents	(	const SoFieldContainer *	from,
		SbBool	copyconnections
	)

protectedvirtual

Makes a deep copy of all data of from into this instance, except external scenegraph references if copyconnections is FALSE.

This is the method that should be overridden by extension node / engine / dragger / whatever subclasses which needs to account for internal data that are not handled automatically.

For copying nodes from application code, you should not invoke this function directly, but rather call the SoNode::copy() function:

SoNode * mynewnode = templatenode->copy();

The same also goes for engines.

Make sure that when you override the copyContents() method in your extension class that you also make it call upwards to it's parent superclass in the inheritance hierarchy, as copyContents() in for instance SoNode and SoFieldContainer does important work. It should go something like this:

void
MyCoinExtensionNode::copyContents(const SoFieldContainer * from,
                                  SbBool copyconnections)
{
  // let parent superclasses do their thing (copy fields, copy
  // instance name, etc etc)
  SoNode::copyContents(from, copyconnections);
  // [..then copy internal data..]
}

Reimplemented from SoGroup.

int SoVRMLLOD::whichToTraverse ( SoAction * action )

protectedvirtual

Returns the child to traverse based on distance to current viewpoint.

Member Data Documentation

SoMFFloat SoVRMLLOD::range

The range for each level.

SoSFVec3f SoVRMLLOD::center

The center used when calculating distance.

SoMFNode SoVRMLLOD::level

The different levels.

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

SoVRMLLOD.h
LOD.cpp

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Member Functions

Static Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation