---
name: "SoVRMLFog"
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/SoVRMLFog"
---

# SoVRMLFog(3)

The SoVRMLFog class is used to specify a global scene fog.

## NAME

SoVRMLFog - The **SoVRMLFog** class is used to specify a global scene fog.

## SYNOPSIS

\#include \<Inventor/VRMLnodes/SoVRMLFog.h\>

Inherits **SoNode**.

### Public Member Functions

virtual **SoType** **getTypeId** (void) const\
 **SoVRMLFog** (void)\
 virtual void **GLRender** (**SoGLRenderAction** \*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 SbBool **affectsState** (void) const\
 virtual void **doAction** (**SoAction** \*action)\
 virtual void **GLRenderBelowPath** (**SoGLRenderAction** \*action)\
 virtual void **GLRenderInPath** (**SoGLRenderAction** \*action)\
 virtual void **GLRenderOffPath** (**SoGLRenderAction** \*action)\
 virtual void **callback** (**SoCallbackAction** \*action)\
 virtual void **getBoundingBox** (**SoGetBoundingBoxAction** \*action)\
 virtual void **getMatrix** (**SoGetMatrixAction** \*action)\
 virtual void **handleEvent** (**SoHandleEventAction** \*action)\
 virtual void **pick** (**SoPickAction** \*action)\
 virtual void **rayPick** (**SoRayPickAction** \*action)\
 virtual void **search** (**SoSearchAction** \*action)\
 virtual void **write** (**SoWriteAction** \*action)\
 virtual void **audioRender** (**SoAudioRenderAction** \*action)\
 virtual void **getPrimitiveCount** (**SoGetPrimitiveCountAction** \*action)\
 virtual void **grabEventsSetup** (void)\
 virtual void **grabEventsCleanup** (void)\
 virtual void **startNotify** (void)\
 virtual void **notify** (**SoNotList** \*l)\
 SbUniqueId **getNodeId** (void) const\
 virtual **SoChildList** \* **getChildren** (void) const\
 virtual void **writeInstance** (**SoOutput** \*out)\
 virtual **SoNode** \* **addToCopyDict** (void) const\
 virtual void **copyContents** (const **SoFieldContainer** \*from, SbBool copyconnections)\
 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*.  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 **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

**SoSFString** **fogType**\
 **SoSFFloat** **visibilityRange**\
 **SoSFColor** **color**\

### Protected Member Functions

virtual const **SoFieldData** \* **getFieldData** (void) const\
 virtual **~SoVRMLFog** ()\

Protected Member Functions inherited from **SoNode** **SoNode** (void)\
 virtual **~SoNode** ()\
 virtual SbBool **readInstance** (**SoInput** \*in, unsigned short flags)\

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\
 virtual **SoNotRec** **createNotRec** (void)\

### Static Protected Member Functions

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)\

### Protected Attributes

**SoSFBool** **set\_bind**\
 **SoSFBool** **isBound**\

Protected Attributes inherited from **SoNode** SbUniqueId **uniqueId**\

Protected Attributes inherited from **SoFieldContainer** SbBool **isBuiltIn**\

### 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 }\

Static Protected Attributes inherited from **SoNode** static SbUniqueId **nextUniqueId** = 1\
 static int **nextActionMethodIndex** = 0\

## Detailed Description

The **SoVRMLFog** class is used to specify a global scene fog.

**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:**\

```
Fog {
  exposedField SFColor  color            1 1 1      # [0,1]
  exposedField SFString fogType          "LINEAR"
  exposedField SFFloat  visibilityRange  0          # [0,inf)
  eventIn      SFBool   set_bind
  eventOut     SFBool   isBound
}
```

The Fog node provides a way to simulate atmospheric effects by blending objects with the colour specified by the color field based on the distances of the various objects from the viewer. The distances are calculated in the coordinate space of the Fog node. The visibilityRange specifies the distance in metres (in the local coordinate system) at which objects are totally obscured by the fog. Objects located outside the visibilityRange from the viewer are drawn with a constant colour of color. Objects very close to the viewer are blended very little with the fog color. \

A visibilityRange of 0.0 disables the Fog node. The visibilityRange is affected by the scaling transformations of the Fog node's parents; translations and rotations have no affect on visibilityRange. Values of the visibilityRange field shall be in the range \[0, ). \

Since Fog nodes are bindable children nodes (see 4.6.10, Bindable children nodes http://www.web3d.org/documents/specifications/14772/V2.0/part1/concepts.html#4.6.10), a Fog node stack exists, in which the top- most Fog node on the stack is currently active. To push a Fog node onto the top of the stack, a TRUE value is sent to the set\_bind eventIn. Once active, the Fog node is bound to the browser view. A FALSE value sent to set\_bind, pops the Fog node from the stack and unbinds it from the browser viewer. More details on the Fog node stack can be found in 4.6.10, Bindable children nodes (http://www.web3d.org/documents/specifications/14772/V2.0/part1/concepts.html#4.6.10).

The fogType field controls how much of the fog colour is blended with the object as a function of distance. If fogType is "LINEAR", the amount of blending is a linear function of the distance, resulting in a depth cueing effect. If fogType is "EXPONENTIAL," an exponential increase in blending is used, resulting in a more natural fog appearance. The effect of fog on lighting calculations is described in 4.14, Lighting model (http://www.web3d.org/documents/specifications/14772/V2.0/part1/concepts.html#4.6.14).

## Constructor & Destructor Documentation

### SoVRMLFog::SoVRMLFog (void )

Constructor.

### SoVRMLFog::~SoVRMLFog () \[protected\], \[virtual\]

Destructor.

## Member Function Documentation

### SoType SoVRMLFog::getClassTypeId (void ) \[static\]

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

### SoType SoVRMLFog::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.

Implements **SoBase**.

### const SoFieldData \*\* SoVRMLFog::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 \* SoVRMLFog::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 **SoFieldContainer**.

### void SoVRMLFog::initClass (void ) \[static\]

### void SoVRMLFog::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 **SoNode**.

## Member Data Documentation

### SoSFString SoVRMLFog::fogType

Type of fog. Can be either "LINEAR" or "EXPONENTIAL". Default value is "LINEAR".

### SoSFFloat SoVRMLFog::visibilityRange

Range of visibility. The distance when only the fog color can be seen. Default value is (0.0).

### SoSFColor SoVRMLFog::color

The fog color. Default value is (1, 1, 1).

### SoSFBool SoVRMLFog::set\_bind \[protected\]

An eventIn that is used to bind this node (make the node active).

### SoSFBool SoVRMLFog::isBound \[protected\]

An eventOut that is sent when the node is bound/unbound.

## Author

Generated automatically by Doxygen for Coin from the source code.
