--- name: "SoVRMLLOD" section: "3" platform: "linux" package: "coin" version: "1:4.0.10-1" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/SoVRMLLOD" --- # SoVRMLLOD(3) The SoVRMLLOD class is used to represent various levels of detail based on distance. ## NAME SoVRMLLOD - The **SoVRMLLOD** class is used to represent various levels of detail based on distance. ## SYNOPSIS \#include \ Inherits **SoGroup**. ### Public Member Functions virtual **SoType** **getTypeId** (void) const\ **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)\ virtual void **addWriteReference** (**SoOutput** \*out, SbBool isfromfield=FALSE)\ 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)\ SbUniqueId **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)\ 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*. 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)\ 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 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)\ 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 SbUniqueId **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)\ 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 **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** SbUniqueId **uniqueId**\ Protected Attributes inherited from **SoFieldContainer** SbBool **isBuiltIn**\ Static Protected Attributes inherited from **SoNode** static SbUniqueId **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/documents/specifications/14772/V2.0/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 () \[protected\], \[virtual\] Destructor. ## Member Function Documentation ### SoType SoVRMLLOD::getClassTypeId (void ) \[static\] This static method returns the **SoType** object associated with objects of this class. ### SoType SoVRMLLOD::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**. ### const SoFieldData \*\* SoVRMLLOD::getFieldDataPtr (void ) \[static\], \[protected\] *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. ### const SoFieldData \* SoVRMLLOD::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 **SoGroup**. ### void SoVRMLLOD::initClass (void ) \[static\] ### 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 want to throw geometry primitives at OpenGL override 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 override 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 calculate their bounding box also override 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 calculate their primitive count also override 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) \[protected\], \[virtual\] Notifies all auditors for this instance when changes are made. Reimplemented from **SoNode**. ### SbBool SoVRMLLOD::readInstance (SoInput \* in, unsigned short flags) \[protected\], \[virtual\] 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 / persistent 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) \[protected\], \[virtual\] Makes a deep copy of all data of *from* into this instance, *except* external scene graph references if *copyconnections* is FALSE. This is the method that should be overridden by extension node / engine / dragger / whatever subclasses which need 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 its 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.) SoNode::copyContents(from, copyconnections); // [..then copy internal data..] } ``` Reimplemented from **SoGroup**. ### int SoVRMLLOD::whichToTraverse (SoAction \* action) \[protected\], \[virtual\] 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. ## Author Generated automatically by Doxygen for Coin from the source code.