# SoBase Class Reference
[General classes]

`#include <Inventor/misc/SoBase.h>`

Inheritance diagram for SoBase:

List of all members.

## Detailed Description

The SoBase class is the top-level superclass for a number of class-hierarchies.

SoBase provides the basic interfaces and methods for doing reference counting, type identification and import/export. All classes in Coin which uses these mechanisms are descendent from this class.

## Public Member Functions

void | ref (void) const
void | unref (void) const
void | unrefNoDelete (void) const
int32_t | getRefCount (void) const
void | touch (void)
virtual SoType | getTypeId (void) const=0
SbBool | isOfType (SoType type) const
virtual SbName | getName (void) const
virtual void | setName (const SbName &newname)
virtual void | startNotify (void)
virtual void | notify (SoNotList *l)
void | addAuditor (void *const auditor, const SoNotRec::Type type)
void | removeAuditor (void *const auditor, const SoNotRec::Type type)
const SoAuditorList & | getAuditors (void) const
virtual void | addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
SbBool | shouldWrite (void)
void | assertAlive (void) const

## Static Public Member Functions

void | initClass (void)
SoType | getClassTypeId (void)
void | addName (SoBase *const base, const char *const name)
void | removeName (SoBase *const base, const char *const name)
void | incrementCurrentWriteCounter (void)
void | decrementCurrentWriteCounter (void)
SoBase * | getNamedBase (const SbName &name, SoType type)
int | getNamedBases (const SbName &name, SoBaseList &baselist, SoType type)
SbBool | read (SoInput *in, SoBase *&base, SoType expectedtype)
void | setInstancePrefix (const SbString &c)
void | setTraceRefs (SbBool trace)
SbBool | getTraceRefs (void)
SbBool | connectRoute (SoInput *in, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)
SbBool | readRoute (SoInput *in)

## Protected Types

enum | BaseFlags { IS_ENGINE = 0x01, IS_GROUP = 0x02 }

## Protected Member Functions

| 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
virtual SbBool | readInstance (SoInput *in, unsigned short flags)=0

## Static Protected Member Functions

uint32_t | getCurrentWriteCounter (void)

## Member Enumeration Documentation

enum SoBase::BaseFlags`[protected]`

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

## Constructor & Destructor Documentation

SoBase::SoBase | ( | void |  | ) | `[protected]`

| Constructor. The initial reference count will be set to zero.

SoBase::~SoBase | ( |  | ) | `[protected, virtual]`

Destructor. There should not be any normal circumstance where you need to explicitly delete an object derived from the SoBase class, as the reference counting should take care of deallocating unused objects.

See also:
  unref(), unrefNoDelete()

## Member Function Documentation

void SoBase::initClass | ( | void |  | ) | `[static]`

Sets up initialization for data common to all instances of this class, like submitting necessary information to the Coin type system.

Reimplemented in SoPath, SoCenterballDragger, SoDirectionalLightDragger, SoDragPointDragger, SoDragger, SoHandleBoxDragger, SoJackDragger, SoPointLightDragger, SoRotateCylindricalDragger, SoRotateDiscDragger, SoRotateSphericalDragger, SoScale1Dragger, SoScale2Dragger, SoScale2UniformDragger, SoScaleUniformDragger, SoSpotLightDragger, SoTabBoxDragger, SoTabPlaneDragger, SoTrackballDragger, SoTransformBoxDragger, SoTransformerDragger, SoTranslate1Dragger, SoTranslate2Dragger, SoBoolOperation, SoCalculator, SoComputeBoundingBox, SoConcatenate, SoCounter, SoElapsedTime, SoEngine, SoFieldConverter, SoGate, SoInterpolate, SoOnOff, SoOneShot, SoSelectOne, SoTimeCounter, SoTransformVec3f, SoTriggerAny, SoNodeEngine, SoFieldContainer, SoCenterballManip, SoClipPlaneManip, SoDirectionalLightManip, SoHandleBoxManip, SoJackManip, SoPointLightManip, SoSpotLightManip, SoTabBoxManip, SoTrackballManip, SoTransformBoxManip, SoTransformManip, SoTransformerManip, SoAppearanceKit, SoBaseKit, SoCameraKit, SoInteractionKit, SoLightKit, SoNodeKitListPart, SoSceneKit, SoSeparatorKit, SoShapeKit, SoWrapperKit, SoAnnotation, SoAntiSquish, SoArray, SoAsciiText, SoBaseColor, SoBlinker, SoCallback, SoCamera, SoClipPlane, SoColorIndex, SoComplexity, SoCone, SoCoordinate3, SoCoordinate4, SoCube, SoCylinder, SoDirectionalLight, SoDrawStyle, SoEnvironment, SoEventCallback, SoExtSelection, SoFaceSet, SoFile, SoFont, SoFontStyle, SoGroup, SoImage, SoIndexedFaceSet, SoIndexedLineSet, SoIndexedNurbsCurve, SoIndexedNurbsSurface, SoIndexedShape, SoIndexedTriangleStripSet, SoInfo, SoLOD, SoLabel, SoLevelOfDetail, SoLight, SoLightModel, SoLineSet, SoLinearProfile, SoListener, SoLocateHighlight, SoMarkerSet, SoMaterial, SoMaterialBinding, SoMatrixTransform, SoMultipleCopy, SoNode, SoNonIndexedShape, SoNormal, SoNormalBinding, SoNurbsCurve, SoNurbsProfile, SoNurbsSurface, SoOrthographicCamera, SoPackedColor, SoPathSwitch, SoPendulum, SoPerspectiveCamera, SoPickStyle, SoPointLight, SoPointSet, SoPolygonOffset, SoProfile, SoProfileCoordinate2, SoProfileCoordinate3, SoQuadMesh, SoResetTransform, SoRotation, SoRotationXYZ, SoRotor, SoScale, SoSelection, SoSeparator, SoShape, SoShapeHints, SoShuttle, SoSphere, SoSpotLight, SoSurroundScale, SoSwitch, SoText2, SoText3, SoTexture2, SoTexture2Transform, SoTexture3, SoTexture3Transform, SoTextureCoordinate2, SoTextureCoordinate3, SoTextureCoordinateBinding, SoTextureCoordinateDefault, SoTextureCoordinateEnvironment, SoTextureCoordinateFunction, SoTextureCoordinatePlane, SoTextureScalePolicy, SoTransform, SoTransformSeparator, SoTransformation, SoTranslation, SoTransparencyType, SoTriangleStripSet, SoUnits, SoVertexProperty, SoVertexShape, SoWWWAnchor, SoWWWInline, SoVRMLAnchor, SoVRMLAppearance, SoVRMLAudioClip, SoVRMLBackground, SoVRMLBillboard, SoVRMLBox, SoVRMLCollision, SoVRMLColor, SoVRMLColorInterpolator, SoVRMLCone, SoVRMLCoordinate, SoVRMLCoordinateInterpolator, SoVRMLCylinder, SoVRMLCylinderSensor, SoVRMLDirectionalLight, SoVRMLDragSensor, SoVRMLElevationGrid, SoVRMLExtrusion, SoVRMLFog, SoVRMLFontStyle, SoVRMLGeometry, SoVRMLGroup, SoVRMLImageTexture, SoVRMLIndexedFaceSet, SoVRMLIndexedLine, SoVRMLIndexedLineSet, SoVRMLIndexedShape, SoVRMLInline, SoVRMLInterpolator, SoVRMLLOD, SoVRMLLight, SoVRMLMaterial, SoVRMLMovieTexture, SoVRMLNavigationInfo, SoVRMLNormal, SoVRMLNormalInterpolator, SoVRMLOrientationInterpolator, SoVRMLParent, SoVRMLPixelTexture, SoVRMLPlaneSensor, SoVRMLPointLight, SoVRMLPointSet, SoVRMLPositionInterpolator, SoVRMLProximitySensor, SoVRMLScalarInterpolator, SoVRMLScript, SoVRMLSensor, SoVRMLShape, SoVRMLSound, SoVRMLSphere, SoVRMLSphereSensor, SoVRMLSpotLight, SoVRMLSwitch, SoVRMLText, SoVRMLTexture, SoVRMLTextureCoordinate, SoVRMLTextureTransform, SoVRMLTimeSensor, SoVRMLTouchSensor, SoVRMLTransform, SoVRMLVertexLine, SoVRMLVertexPoint, SoVRMLVertexShape, SoVRMLViewpoint, SoVRMLVisibilitySensor, and SoVRMLWorldInfo.

void SoBase::ref | ( | void |  | ) | const

Increase the reference count of the object. This might be necessary to do explicitly from user code for certain situations (chiefly to avoid premature deletion), but is usually called from other instances within the Coin library when objects are made dependent on each other.

See also:
  unref(), unrefNoDelete()

void SoBase::unref | ( | void |  | ) | const

Decrease the reference count of an object. If the reference count reaches zero, the object will delete itself. Be careful when explicitly calling this method, beware that you usually need to match user level calls to ref() with calls to either unref() or unrefNoDelete() to avoid memory leaks.

See also:
  ref(), unrefNoDelete()

void SoBase::unrefNoDelete | ( | void |  | ) | const

Decrease reference count, but do not delete ourself if the count reaches zero.

See also:
  unref()

int32_t SoBase::getRefCount | ( | void |  | ) | const

| Returns number of objects referring to this object.

void SoBase::touch | ( | void |  | ) |

| Force an update, in the sense that all objects connected to this will have to re-check the values of their inter-dependent data. This is often used as an effective way of manually triggering a redraw by application programmers.

SoType SoBase::getTypeId | ( | void |  | ) | const`[pure 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
        }
        else if (node->getTypeId().isOfType(SoGroup::getClassTypeId())) {
          SoGroup * group = (SoGroup *)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.

Implemented in SoPath, and SoVRMLScript.

SbBool SoBase::isOfType | ( | SoType | type | ) | const

| Returns `TRUE` if the type of this object is either of the same type or inherited from type.

SoType SoBase::getClassTypeId | ( | void |  | ) | `[static]`

| This static method returns the SoType object associated with objects of this class. Reimplemented in SoPath, SoEngine, SoNodeEngine, SoFieldContainer, SoNode, and SoVRMLScript.

SbName SoBase::getName | ( | void |  | ) | const`[virtual]`

| Returns name of object. If no name has been given to this object, the returned SbName will contain the empty string.

void SoBase::setName | ( | const SbName & | newname | ) | `[virtual]`

Set the name of this object.

Characters that are invalid to use as parts of names for SoBase derived objects will be automatically replaced by underscore characters. If the name starts with an invalid character, the new name will be preceded by an underscore character.

See also:
  getName(), SbName::isBaseNameStartChar(), SbName::isBaseNameChar()

void SoBase::addName | ( | SoBase *const | b,
|  | const char *const | name
| ) | `[static]`

| Adds a name<->object mapping to the global dictionary.

void SoBase::removeName | ( | SoBase *const | b,
|  | const char *const | name
| ) | `[static]`

| Removes a name<->object mapping from the global dictionary.

void SoBase::startNotify | ( | void |  | ) | `[virtual]`

| This is the method which starts the notification sequence after changes. At the end of a notification sequence, all "immediate" sensors (i.e. sensors set up with a zero priority) are triggered. Reimplemented in SoNode.

void SoBase::notify | ( | SoNotList * | l | ) | `[virtual]`

Notifies all auditors for this instance when changes are made.

Reimplemented in SoEngine, SoNodeEngine, SoFieldContainer, SoAsciiText, SoBlinker, SoImage, SoLOD, SoLevelOfDetail, SoMaterial, SoNode, SoPackedColor, SoSeparator, SoShape, SoSwitch, SoText3, SoTexture2, SoTexture3, SoVertexProperty, SoVertexShape, SoVRMLAppearance, SoVRMLBillboard, SoVRMLCollision, SoVRMLElevationGrid, SoVRMLExtrusion, SoVRMLGeometry, SoVRMLGroup, SoVRMLIndexedLine, SoVRMLIndexedShape, SoVRMLLOD, SoVRMLParent, SoVRMLPixelTexture, SoVRMLProximitySensor, SoVRMLScript, SoVRMLShape, SoVRMLSwitch, SoVRMLText, SoVRMLTimeSensor, SoVRMLTouchSensor, SoVRMLTransform, SoVRMLVertexLine, SoVRMLVertexPoint, and SoVRMLVertexShape.

void SoBase::addAuditor | ( | void *const | auditor,
|  | const SoNotRec::Type | type
| ) |

Add an auditor to notify whenever the object changes in any significant way.

See also:
  removeAuditor()

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

Remove an auditor from the list. auditor will then no longer be notified whenever any updates are made to this object.

See also:
  addAuditor()

const SoAuditorList & SoBase::getAuditors | ( | void |  | ) | const

Returns list of objects auditing this object.

See also:
  addAuditor(), removeAuditor()

void SoBase::addWriteReference | ( | SoOutput * | out,
|  | SbBool | isfromfield = FALSE
| ) | `[virtual]`

| This method is used during the first write pass of a write action to count the number of references to this object in the scene graph. Reimplemented in SoFieldContainer, and SoBaseKit.

SbBool SoBase::shouldWrite | ( | void |  | ) |

Returns `TRUE` if this object should be written out during a write action. Will return `FALSE` if no references to this object has been made in the scene graph.

Note that connections from the fields of fieldcontainer objects is not alone a valid reason for writing out the object -- there must also be at least one reference directly from another SoBase (like a parent/child relationship, for instance).

This method will return a valid result only during the second pass of write actions.

void SoBase::incrementCurrentWriteCounter | ( | void |  | ) | `[static]`

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

void SoBase::decrementCurrentWriteCounter | ( | void |  | ) | `[static]`

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

SoBase * SoBase::getNamedBase | ( | const SbName & | name,
|  | SoType | type
| ) | `[static]`

| Returns the object of type, or derived from type, registered under name. If several has been registered under the same name with the same type, returns the last one which was registered. If no object of a valid type or subtype has been registered with the given name, returns `NULL`.

int SoBase::getNamedBases | ( | const SbName & | name,
|  | SoBaseList & | baselist,
|  | SoType | type
| ) | `[static]`

| Returns the number of objects of type type, or derived from type, registered under name. All matches will also be appended to baselist.

SbBool SoBase::read | ( | SoInput * | in,
|  | SoBase *& | base,
|  | SoType | expectedtype
| ) | `[static]`

Read next SoBase derived instance from the in stream, check that it is derived from expectedtype and place a pointer to the newly allocated instance in base.

`FALSE` is returned on read errors, mismatch with the expectedtype, or if there are attempts at referencing (through the `USE` keyword) unknown instances.

If we return `TRUE` with base equal to `NULL`, three things might have happened:

1. End-of-file. Use SoInput::eof() after calling this method to detect end-of-file conditions.

2. in didn't have a valid identifier name at the stream for us to read. This happens either in the case of errors, or when all child nodes of a group has been read. Check if the next character in the stream is a '}' to detect the latter case.

3. A child was given as the `NULL` keyword. This can happen when reading the contents of SoSFNode or SoMFNode fields.

If `TRUE` is returned and base is not `NULL` upon return, the instance was allocated and initialized according to what was read from the in stream.

void SoBase::setInstancePrefix | ( | const SbString & | c | ) | `[static]`

| Referenced instances of SoBase are written as "DEF NamePrefixNumber" when exported. "Name" is the name of the base instance from setName(), "Prefix" is common for all objects and can be set by this method (default is "+"), and "Number" is a unique id which is necessary if multiple objects have the same name. If you want the prefix to be something else than "+", use this method.

void SoBase::setTraceRefs | ( | SbBool | trace | ) | `[static]`

| Set to `TRUE` to activate debugging of reference counting, which could aid in finding hard to track down problems with accesses to freed memory or memory leaks. Note: this will produce lots of debug information in any "normal" running system, so use sensibly. The reference tracing functionality will be disabled in "release versions" of the Coin library.

SbBool SoBase::getTraceRefs | ( | void |  | ) | `[static]`

Return the status of the reference tracing flag.

See also:
  setTraceRefs()

SbBool SoBase::connectRoute | ( | SoInput * | in,
|  | const SbName & | fromnodename,
|  | const SbName & | fromfieldname,
|  | const SbName & | tonodename,
|  | const SbName & | tofieldname
| ) | `[static]`

Connect a route from the node named fromnodename's field fromfieldname to the node named tonodename's field tofieldname. This method will consider the fields types (event in, event out, etc) when connecting.

This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

Since:
  Coin 2.0

void SoBase::assertAlive | ( | void |  | ) | const

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

There are 4 bits allocated for each SoBase-object for a bitpattern that indicates the object is still "alive". The pattern is changed when the object is destructed. If this method is then called after destruction, an assert will hit.

This is used internally in Coin (in for instance SoBase::ref()) to try to detect when the instance has been prematurely destructed. This is a very common mistake to make by application programmers (letting the refcount dip to zero before it should, that is), so the extra piece of assistance through the accompanying assert() in this method to detect dangling references to the object, with subsequent memory corruption and mysterious crashes, should be a Good Thing.

This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

Since:
  Coin 2.0

SbBool SoBase::readRoute | ( | SoInput * | in | ) | `[static]`

| This API member is considered internal to the library, as it is not likely to be of interest to the application programmer. Reads a (VRML97) ROUTE. We decided to also add support for routes in Coin, as a generic feature, since we think it is nicer than setting up field connections inside the nodes.

void SoBase::destroy | ( | void |  | ) | `[protected, virtual]`

| Cleans up all hanging references to and from this instance, and then commits suicide. Called automatically when the reference count goes to zero.

SbBool SoBase::hasMultipleWriteRefs | ( | void |  | ) | const`[protected]`

| Returns `TRUE` if this object will be written more than once upon export. Note that the result from this method is only valid during the second pass of a write action (and partly during the COUNT_REFS pass).

SbBool SoBase::writeHeader | ( | SoOutput * | out,
|  | SbBool | isgroup,
|  | SbBool | isengine
| ) | const`[protected]`

Write out the header of any SoBase derived object. The header consists of the `DEF` keyword and the object name (if the object has a name, otherwise these will be skipped), the class name and a left bracket.

Alternatively, the object representation may be made up of just the `USE` keyword plus the object name, if this is the second or subsequent reference written to the file.

If the object has been completed just by writing the header (which will be the case if we're writing multiple references of an object), we return `TRUE`, otherwise `FALSE`.

If we return `FALSE` (i.e. there's more to write), we will increment the indentation level.

See also:
  writeFooter(), SoOutput::indent()

void SoBase::writeFooter | ( | SoOutput * | out | ) | const`[protected]`

| This method will terminate the block representing an SoBase derived object.

const char * SoBase::getFileFormatName | ( | void |  | ) | const`[protected, virtual]`

| Returns the class name this object should be written under. Default string returned is the name of the class from the type system. User extensions nodes and engines override this method to return the name of the extension (instead of "UnknownNode" or "UnknownEngine").

SbBool SoBase::readInstance | ( | SoInput * | in,
|  | unsigned short | flags
| ) | `[protected, pure 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 / 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.

Implemented in SoEngine, SoNodeEngine, SoFieldContainer, SoBaseKit, SoInteractionKit, SoNodeKitListPart, SoFile, SoGroup, SoImage, SoNode, SoNormalBinding, SoSeparator, SoTexture2, SoTexture3, SoTextureCoordinateBinding, SoWWWInline, SoVRMLImageTexture, SoVRMLLOD, SoVRMLParent, SoVRMLPixelTexture, and SoVRMLSwitch.

uint32_t SoBase::getCurrentWriteCounter | ( | 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.

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

- SoBase.h
- SoBase.cpp