SoAlphaTest Class Reference

The SoAlphaTest class is a node used to control the GL alpha test function. More...

#include <Inventor/nodes/SoAlphaTest.h>

Inheritance diagram for SoAlphaTest:

Public Types
enum	Function {   NONE , NEVER , ALWAYS , LESS ,   LEQUAL , EQUAL , GEQUAL , GREATER ,   NOTEQUAL }
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 }

Public Member Functions
	SoAlphaTest (void)
virtual SoType	getTypeId (void) const
virtual void	GLRender (SoGLRenderAction *action)
Public Member Functions inherited from SoNode
virtual SoNode *	addToCopyDict (void) const
virtual SbBool	affectsState (void) const
virtual void	audioRender (SoAudioRenderAction *action)
virtual void	callback (SoCallbackAction *action)
virtual SoNode *	copy (SbBool copyconnections=FALSE) const
virtual void	copyContents (const SoFieldContainer *from, SbBool copyconnections)
virtual SoFieldContainer *	copyThroughConnection (void) const
virtual void	doAction (SoAction *action)
virtual void	getBoundingBox (SoGetBoundingBoxAction *action)
virtual SoChildList *	getChildren (void) const
virtual void	getMatrix (SoGetMatrixAction *action)
SbUniqueId	getNodeId (void) const
NodeType	getNodeType (void) const
virtual void	getPrimitiveCount (SoGetPrimitiveCountAction *action)
virtual void	GLRenderBelowPath (SoGLRenderAction *action)
virtual void	GLRenderInPath (SoGLRenderAction *action)
virtual void	GLRenderOffPath (SoGLRenderAction *action)
virtual void	grabEventsCleanup (void)
virtual void	grabEventsSetup (void)
virtual void	handleEvent (SoHandleEventAction *action)
SbBool	isOverride (void) const
virtual void	notify (SoNotList *l)
virtual void	pick (SoPickAction *action)
virtual void	rayPick (SoRayPickAction *action)
virtual void	search (SoSearchAction *action)
void	setNodeType (const NodeType type)
void	setOverride (const SbBool state)
virtual void	startNotify (void)
virtual void	write (SoWriteAction *action)
virtual void	writeInstance (SoOutput *out)
Public Member Functions inherited from SoFieldContainer
virtual void	addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
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 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
SoSFEnum	function
SoSFFloat	value

Protected Member Functions
virtual	~SoAlphaTest ()
virtual const SoFieldData *	getFieldData (void) const
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 SoNotRec	createNotRec (void)
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 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
Protected Types inherited from SoBase
enum	BaseFlags { IS_ENGINE = 0x01 , IS_GROUP = 0x02 }
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 SoAlphaTest class is a node used to control the GL alpha test function.

With this node you can control the OpenGL alpha test function. The alpha test function enables you to discard fragments based on its alpha value. For instance, if you set the function to GREATER and value to 0.5, only fragments with alpha value greater than 0.5 will be rendered.

Alpha testing is typically used when rendering textures where all pixels are either completely opaque or completely transparent. Transparency sorting problems are avoided when alpha testing is used instead of blending, since depth testing can still be enabled and no sorting or delayed rendering is needed.

To enable alpha testing instead of transparency blending, insert a TransparencyType node with value = NONE, and an AlphaTest node with function set to GREATER and value set to for instance 0.01.

FILE FORMAT/DEFAULTS:

AlphaTest {
    function NONE
    value 0.5
}

Be aware that this class is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

Since

Coin 4.0

Member Enumeration Documentation

Function

enum SoAlphaTest::Function

Enumeration for the various alpha functions.

Enumerator
NONE	No alpha test is performed.
NEVER	Never passes.
ALWAYS	Always passes.
LESS	Passes if the incoming alpha value is less than the stored alpha value.
LEQUAL	Passes if the incoming alpha value is less than or equal to the stored alpha value.
EQUAL	Passes if the incoming alpha value is equal to the stored alpha value.
GEQUAL	Passes if the incoming alpha value is greater than or equal to the stored alpha value.
GREATER	Passes if the incoming alpha value is greater than the stored alpha value.
NOTEQUAL	Passes if the incoming alpha value is not equal to the stored alpha value.

Constructor & Destructor Documentation

SoAlphaTest()

SoAlphaTest::SoAlphaTest

(

void

)

Constructor.

~SoAlphaTest()

SoAlphaTest::~SoAlphaTest ( )

protectedvirtual

Destructor.

Member Function Documentation

getClassTypeId()

SoType SoAlphaTest::getClassTypeId ( void )

static

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

getFieldData()

const SoFieldData * SoAlphaTest::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 SoFieldContainer.

getFieldDataPtr()

const SoFieldData ** SoAlphaTest::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.

getTypeId()

SoType SoAlphaTest::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.

GLRender()

void SoAlphaTest::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

function

SoSFEnum SoAlphaTest::function

Which alpha function to use. Defaults to NONE.

value

SoSFFloat SoAlphaTest::value

The value the function will compare against when applicable. Default is 0.5.

---

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

• SoAlphaTest.h
• SoAlphaTest.cpp