SoAlphaTest(3)

📦
version 4.0.10 · 4 versions
, in fedora 43, fedora 44

SoAlphaTest(3) — Coin

okay bestie, this is part 1 of 2, so grab your emotional support water bottle. 💖 We're decoding the SoAlphaTest node and it's giving main character energy.

🌸 NAME 🌸

SoAlphaTest — the class that is literally a node used to control the GL alpha test function. periodt.

✨ SYNOPSIS ✨

first things first, the include. no cap, type it exactly:

#include <Inventor/nodes/SoAlphaTest.h>

Inherits SoNode. slay.

🎀 Public Types 🎀

the Function enum is serving:

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

🦋 Public Types inherited from SoNode 🦋

and here's the inherited enum from SoNode, iconic:

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 💖

our own functions, the moment:

  • virtual SoType getTypeId (void) const
  • SoAlphaTest (void)
  • virtual void GLRender (SoGLRenderAction *action)

🌈 Public Member Functions inherited from SoNode 🌈

now the inherited besties from SoNode — yes, all of them, we don't skip. 💅

  • 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) — 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 🌟

  • SoSFEnum function
  • SoSFFloat value

🔥 Protected Member Functions 🔥

  • virtual const SoFieldData * getFieldData (void) const
  • virtual ~SoAlphaTest ()

💀 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)

🫶 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 SbUniqueId nextUniqueId = 1
  • static int nextActionMethodIndex = 0

💖 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 🌈

🎀 enum SoAlphaTest::Function 🎀

okay so this enum is literally just the menu of alpha functions you can pick from. that's it. that's the whole vibe check. ✨

  • NONE — no alpha test is performed. we're not testing anything, we're just living. 💅
  • NEVER — never passes. not once. not ever. not even a little. 💀
  • ALWAYS — always passes. every time. no exceptions. iconic behavior honestly 👑
  • 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. it's giving "we're the same fr fr" 🫶
  • 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. the contrarian of the group 🙈

🛠️ Constructor & Destructor Documentation 🛠️

SoAlphaTest::SoAlphaTest (void)

Constructor. that's it, that's the description bestie, she builds the thing ✨

SoAlphaTest::~SoAlphaTest () [protected], [virtual]

Destructor. and she tears it down. note the protected and virtual tags — this is a member you don't get to poke from outside, and it plays nice with inheritance. 🦋

💖 Member Function Documentation 💖

SoType SoAlphaTest::getClassTypeId (void) [static]

This static method returns the SoType object associated with objects of this class. static, so you can call it without even having an instance. queen of accessibility. 👑

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.

const SoFieldData ** SoAlphaTest::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. so like… it's there, it's doing its job, but it's not for you. no offense. 🙈

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

const SoFieldData * SoAlphaTest::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 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 📦

SoSFEnum SoAlphaTest::function

Which alpha function to use. Defaults to NONE. so if you don't say anything, she's not testing anything, periodt.

SoSFFloat SoAlphaTest::value

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

🌸 Author 🌸

Generated automatically by Doxygen for Coin from the source code.

and that's the whole page bestie!! 💖 you made it to the end, so proud of you 🥹✨

this was Coin version 4.0.10, dated Thu Jun 25 2026 00:00:00, and you've been reading SoAlphaTest(3). slay, go touch some grass, ily 🌈🦋🎀

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