NAME¶

SoCallback — provides custom behavior during actions

INHERITS FROM¶

SoBase > SoFieldContainer > SoNode > SoCallback

SYNOPSIS¶

#include <Inventor/nodes/SoCallback.h>

typedef void SoCallbackCB(void *userData, SoAction *action)

Methods from class SoCallback:

SoCallback()

void setCallback(SoCallbackCB *func, void *userData = NULL)

static SoType getClassTypeId()

Methods from class SoNode:

void setOverride(SbBool state)

SbBool isOverride() const

SoNode * copy(SbBool copyConnections = FALSE) const

virtual SbBool affectsState() const

static SoNode * getByName(const SbName &name)

static int getByName(const SbName &name, SoNodeList &list)

Methods from class SoFieldContainer:

void setToDefaults()

SbBool hasDefaultValues() const

SbBool fieldsAreEqual(const SoFieldContainer *fc) const

void copyFieldValues(const SoFieldContainer *fc, SbBool copyConnections = FALSE)

SbBool set(const char *fieldDataString)

void get(SbString &fieldDataString)

virtual int getFields(SoFieldList &resultList) const

virtual SoField * getField(const SbName &fieldName) const

SbBool getFieldName(const SoField *field, SbName &fieldName) const

SbBool isNotifyEnabled() const

SbBool enableNotify(SbBool flag)

Methods from class SoBase:

void ref()

void unref() const

void unrefNoDelete() const

void touch()

virtual SoType getTypeId() const

SbBool isOfType(SoType type) const

virtual void setName(const SbName &name)

virtual SbName getName() const

DESCRIPTION¶

This node provides a general mechanism for inserting callback functions into a scene graph. The callback function registered with the node is called each time the node is traversed while performing any scene graph action. The callback function is passed a pointer to the action being performed and a user data pointer registered with the callback function. You can use this node to make nonstandard OpenGL calls while rendering. If you do, be careful not to interfere with Inventor's use of OpenGL.

If you use a callback node for GL rendering, you should be careful to follow render caching rules. If your callback node can make different rendering calls each time it is traversed, it cannot be cached. In such a case, the node should invalidate any open caches, as in the following example:

void
myCallbackFunc(void *d, SoAction *action) {


    if (action->isOfType(SoGLRenderAction::getClassTypeId())) {
	// Make my custom GL calls
	((MyClass *) d)->myRender();
	
	// Invalidate the state so that a cache is not made
	SoCacheElement::invalidate(action->getState());


    }
}

METHODS¶

SoCallback()

Creates a callback node with default settings.

void setCallback(SoCallbackCB *func, void *userData = NULL)

Sets pointer to callback function and user data. By default, the function pointer in the node is NULL and does nothing.

static SoType getClassTypeId()

Returns type identifier for this class.

ACTION BEHAVIOR¶

SoGLRenderAction, SoBoundingBoxAction, SoPickAction

Calls the specified callback function for all actions.

FILE FORMAT/DEFAULTS¶

Callback {
}

SEE ALSO¶

SoAction, SoCallbackAction, SoEventCallback