The SoLOD class is used to choose a child based distance between viewer and object. More...

#include <Inventor/nodes/SoLOD.h>

Inheritance diagram for SoLOD:

Public Member Functions
	SoLOD (int numchildren)

	SoLOD (void)

virtual void	audioRender (SoAudioRenderAction *action)

virtual void	callback (SoCallbackAction *action)

virtual void	doAction (SoAction *action)

virtual void	getBoundingBox (SoGetBoundingBoxAction *action)

virtual void	getPrimitiveCount (SoGetPrimitiveCountAction *action)

virtual SoType	getTypeId (void) const

virtual void	GLRender (SoGLRenderAction *action)

virtual void	GLRenderBelowPath (SoGLRenderAction *action)

virtual void	GLRenderInPath (SoGLRenderAction *action)

virtual void	GLRenderOffPath (SoGLRenderAction *action)

virtual void	notify (SoNotList *nl)

virtual void	rayPick (SoRayPickAction *action)

Public Member Functions inherited from SoGroup
	SoGroup (int nchildren)

	SoGroup (void)

virtual void	addChild (SoNode *node)

virtual void	addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)

virtual int	findChild (const SoNode *node) const

virtual SoNode *	getChild (int index) const

virtual SoChildList *	getChildren (void) const

virtual void	getMatrix (SoGetMatrixAction *action)

virtual int	getNumChildren (void) const

virtual void	handleEvent (SoHandleEventAction *action)

virtual void	insertChild (SoNode *child, int newchildindex)

virtual void	pick (SoPickAction *action)

virtual void	removeAllChildren (void)

virtual void	removeChild (int childindex)

virtual void	removeChild (SoNode *child)

virtual void	replaceChild (int index, SoNode *newchild)

virtual void	replaceChild (SoNode oldchild, SoNode newchild)

virtual void	search (SoSearchAction *action)

virtual void	write (SoWriteAction *action)

Public Member Functions inherited from SoNode
virtual SoNode *	addToCopyDict (void) const

virtual SbBool	affectsState (void) const

virtual SoNode *	copy (SbBool copyconnections=FALSE) const

virtual SoFieldContainer *	copyThroughConnection (void) const

SbUniqueId	getNodeId (void) const

NodeType	getNodeType (void) const

virtual void	grabEventsCleanup (void)

virtual void	grabEventsSetup (void)

SbBool	isOverride (void) const

void	setNodeType (const NodeType type)

void	setOverride (const SbBool state)

virtual void	startNotify (void)

virtual void	writeInstance (SoOutput *out)

Public Member Functions inherited from SoFieldContainer
void	copyFieldValues (const SoFieldContainer *container, SbBool copyconnections=FALSE)

SbBool	enableNotify (const SbBool flag)

SbBool	fieldsAreEqual (const SoFieldContainer *container) const

void	get (SbString &fielddata)

void	get (SbString &fielddata, SoOutput *out)

virtual int	getAllFields (SoFieldList &l) const

virtual SoField *	getEventIn (const SbName &name) const

virtual SoField *	getEventOut (const SbName &name) const

virtual SoField *	getField (const SbName &name) const

SbBool	getFieldName (const SoField *const field, SbName &name) const

virtual int	getFields (SoFieldList &l) const

virtual void	getFieldsMemorySize (size_t &managed, size_t &unmanaged) const

SbBool	getIsBuiltIn (void) const

void *	getUserData (void) const

SbBool	hasDefaultValues (void) const

SbBool	isNotifyEnabled (void) const

SbBool	set (const char *const fielddata)

SbBool	set (const char fielddata, SoInput input)

void	setToDefaults (void)

void	setUserData (void *userdata) const

virtual SbBool	validateNewFieldValue (SoField field, void newval)

Public Member Functions inherited from SoBase
void	addAuditor (void *const auditor, const SoNotRec::Type type)

void	assertAlive (void) const

const SoAuditorList &	getAuditors (void) const

virtual SbName	getName (void) const

int32_t	getRefCount (void) const

SbBool	isOfType (SoType type) const
	Returns `TRUE` if the type of this object is either of the same type or inherited from type.

void	ref (void) const

void	removeAuditor (void *const auditor, const SoNotRec::Type type)

virtual void	setName (const SbName &newname)

SbBool	shouldWrite (void)

void	touch (void)

void	unref (void) const

void	unrefNoDelete (void) const

Static Public Member Functions
static SoType	getClassTypeId (void)

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 Public Member Functions inherited from SoGroup
static SoType	getClassTypeId (void)

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 Public Member Functions inherited from SoNode
static void	audioRenderS (SoAction action, SoNode node)

static void	callbackS (SoAction action, SoNode node)

static int	getActionMethodIndex (const SoType type)

static void	getBoundingBoxS (SoAction action, SoNode node)

static SoNode *	getByName (const SbName &name)

static int	getByName (const SbName &name, SoNodeList &l)

static SoType	getClassTypeId (void)

static uint32_t	getCompatibilityTypes (const SoType &nodetype)

static void	getMatrixS (SoAction action, SoNode node)

static SbUniqueId	getNextNodeId (void)

static void	getPrimitiveCountS (SoAction action, SoNode node)

static void	GLRenderS (SoAction action, SoNode node)

static void	handleEventS (SoAction action, SoNode node)

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 void	initClasses (void)

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 Public Member Functions inherited from SoFieldContainer
static void	addCopy (const SoFieldContainer orig, const SoFieldContainer copy)

static SoFieldContainer *	checkCopy (const SoFieldContainer *orig)

static void	cleanupClass (void)

static void	copyDone (void)

static SoFieldContainer *	findCopy (const SoFieldContainer *orig, const SbBool copyconnections)

static SoType	getClassTypeId (void)
	This static method returns the SoType object associated with objects of this class.

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 void	initCopyDict (void)

Static Public Member Functions inherited from SoBase
static void	addName (SoBase const base, const char const name)

static SbBool	connectRoute (SoInput *input, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)

static void	decrementCurrentWriteCounter (void)

static SoType	getClassTypeId (void)
	This static method returns the SoType object associated with objects of this class.

static SoBase *	getNamedBase (const SbName &name, SoType type)

static int	getNamedBases (const SbName &name, SoBaseList &baselist, SoType type)

static SbBool	getTraceRefs (void)

static void	incrementCurrentWriteCounter (void)

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 SbBool	read (SoInput input, SoBase &base, SoType expectedtype)

static SbBool	readRoute (SoInput *input)

static void	removeName (SoBase const base, const char const name)

static void	setInstancePrefix (const SbString &c)

static void	setTraceRefs (SbBool trace)

Public Attributes
SoSFVec3f	center

SoMFFloat	range

Protected Member Functions
virtual	~SoLOD ()

virtual const SoFieldData *	getFieldData (void) const

virtual int	whichToTraverse (SoAction *)

Protected Member Functions inherited from SoGroup
virtual	~SoGroup ()

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

virtual SoNotRec	createNotRec (void)

virtual SbBool	readChildren (SoInput *in)

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

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)

virtual const char *	getFileFormatName (void) const

SbBool	hasMultipleWriteRefs (void) const

void	writeFooter (SoOutput *out) const

SbBool	writeHeader (SoOutput *out, SbBool isgroup, SbBool isengine) 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 int	getNextActionMethodIndex (void)

static void	incNextActionMethodIndex (void)

static void	setCompatibilityTypes (const SoType &nodetype, const uint32_t bitmask)

static void	setNextActionMethodIndex (int index)

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
SbUniqueId	uniqueId

Protected Attributes inherited from SoFieldContainer
SbBool	isBuiltIn

Static Protected Attributes inherited from SoNode
static int	nextActionMethodIndex = 0

static SbUniqueId	nextUniqueId = 1

Detailed Description

The SoLOD class is used to choose a child based distance between viewer and object.

The class documentation for the SoLOD node class would be similar enough to that of SoLevelOfDetail that we will refer you to look at that one first. It will explain the general principles of what a level-of-detail mechanism is, and why and how to use it.

(The main difference between SoLOD and SoLevelOfDetail is that SoLOD uses the faster "distance-to-viewer" technique for implementing level-of-detail functionality, versus the more correct (but potentially slower) "projected-bbox-area" technique used by SoLevelOfDetail.)

Here's a mockup example (in Inventor file format style, but easily converted to code) that shows how to use this node:

LOD {
   range [ 10, 20, 30, 40 ]
 
   Sphere { }
   Cylinder { }
   Cone { }
   Cube { }
   Info { }
}

For the sub-scene graph above, when the LOD-object is less than 10 units away from the viewpoint camera, an SoSphere will be shown. For distances 10 - 20 units away, this will be changed to the SoCylinder, and so on. For distances of more than 40 units from the camera, an SoInfo node will be traversed / rendered – i.e., nothing will be shown. (This is a common "trick" used to optimize rendering when models get far enough away from the camera that we want to remove them completely).

Note that when using an SoOrthographicCamera in the examiner viewers of the SoQt, SoWin and SoXt libraries, it will seem like the SoLOD node is not working when using the "Zoom" functionality. What happens is that an SoOrthographicCamera is not actually moved, the "zoom" effect is accomplished simply by changing its height-of-view setting (i.e. the value of the SoOrthographicCamera::height field), but its position remains constant. So the distance to the camera will not change, which means SoLOD will pick the same child, no matter how much one "zooms".

(The SoLevelOfDetail node uses the screen space area of the object to decide when to switch children, so that node will still work with SoOrthographicCamera.)

FILE FORMAT/DEFAULTS:

LOD {
    center 0 0 0
    range [  ]
}

Since: SGI Inventor 2.1

See also: SoLevelOfDetail

Constructor & Destructor Documentation

◆ SoLOD() [1/2]

SoLOD::SoLOD ( void )

Default constructor.

◆ SoLOD() [2/2]

SoLOD::SoLOD ( int numchildren )

Constructor.

The argument should be the approximate number of children which is expected to be inserted below this node. The number need not be exact, as it is only used as a hint for better memory resource allocation.

◆ ~SoLOD()

SoLOD::~SoLOD ( )

protectedvirtual

Destructor.

Member Function Documentation

◆ audioRender()

void SoLOD::audioRender ( SoAudioRenderAction * action )

virtual

Action method for SoAudioRenderAction.

Does common processing for SoAudioRenderAction action instances.

Reimplemented from SoGroup.

◆ callback()

void SoLOD::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.

◆ doAction()

void SoLOD::doAction ( SoAction * action )

virtual

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

Reimplemented from SoGroup.

◆ getBoundingBox()

void SoLOD::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.

◆ getClassTypeId()

SoType SoLOD::getClassTypeId ( void )

static

This static method returns the SoType object associated with objects of this class.

◆ getFieldData()

const SoFieldData * SoLOD::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.

◆ getFieldDataPtr()

const SoFieldData ** SoLOD::getFieldDataPtr ( void )

staticprotected

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

Returns the SoFieldData class which holds information about fields in this node.

◆ getPrimitiveCount()

void SoLOD::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 calculate their primitive count also override this method to change the relevant state variables.

Reimplemented from SoGroup.

◆ getTypeId()

SoType SoLOD::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.

Reimplemented from SoGroup.

◆ GLRender()

void SoLOD::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.

◆ GLRenderBelowPath()

void SoLOD::GLRenderBelowPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

◆ GLRenderInPath()

void SoLOD::GLRenderInPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

◆ GLRenderOffPath()

void SoLOD::GLRenderOffPath ( SoGLRenderAction * action )

virtual

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

Reimplemented from SoNode.

◆ notify()

void SoLOD::notify ( SoNotList * l )

virtual

Notifies all auditors for this instance when changes are made.

Reimplemented from SoNode.

◆ rayPick()

void SoLOD::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 override this method.

Reimplemented from SoNode.

◆ whichToTraverse()

int SoLOD::whichToTraverse ( SoAction * action )

protectedvirtual

Returns the child to traverse based on the ranges in SoLOD::range. Will clamp to index to the number of children. This method will return -1 if no child should be traversed. This will only happen if the node has no children though.

Member Data Documentation

◆ center

SoSFVec3f SoLOD::center

This vector represents an offset within the object from the geometric center point to the center point the application programmer would actually like the distance between the viewer and the object to be calculated from.

Default value is [0, 0, 0]. It is usually not necessary to change this field.

◆ range

SoMFFloat SoLOD::range

The distance ranges which decides when to use each child for traversal / rendering. See usage example in main class documentation of SoLOD for an explanation of how this vector should be set up correctly.

By default this vector just contains a single value 0.0f.

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

SoLOD.h
SoLOD.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

◆ SoLOD() [1/2]

◆ SoLOD() [2/2]

◆ ~SoLOD()

Member Function Documentation

◆ audioRender()

◆ callback()

◆ doAction()

◆ getBoundingBox()

◆ getClassTypeId()

◆ getFieldData()

◆ getFieldDataPtr()

◆ getPrimitiveCount()

◆ getTypeId()

◆ GLRender()

◆ GLRenderBelowPath()

◆ GLRenderInPath()

◆ GLRenderOffPath()

◆ notify()

◆ rayPick()

◆ whichToTraverse()

Member Data Documentation

◆ center

◆ range