SoHandleEventAction Class Reference

The SoHandleEventAction class distributes user events to the scene. More...

#include <Inventor/actions/SoHandleEventAction.h>

Inheritance diagram for SoHandleEventAction:

Public Member Functions
	SoHandleEventAction (const SbViewportRegion &viewportregion)
virtual	~SoHandleEventAction (void)
const SoEvent *	getEvent (void) const
SoNode *	getGrabber (void) const
const SoPickedPoint *	getPickedPoint (void)
const SoPickedPointList &	getPickedPointList (void)
float	getPickRadius (void) const
SoNode *	getPickRoot (void) const
virtual SoType	getTypeId (void) const
const SbViewportRegion &	getViewportRegion (void) const
SbBool	isHandled (void) const
void	releaseGrabber (void)
void	setEvent (const SoEvent *ev)
void	setGrabber (SoNode *node)
void	setHandled (void)
void	setPickRadius (const float radiusinpixels)
void	setPickRoot (SoNode *node)
void	setViewportRegion (const SbViewportRegion &newregion)
Public Member Functions inherited from SoAction
virtual	~SoAction (void)
virtual void	apply (const SoPathList &pathlist, SbBool obeysrules=FALSE)
void	apply (SoAction *beingApplied)
virtual void	apply (SoNode *root)
virtual void	apply (SoPath *path)
const SoPath *	getCurPath (void)
PathCode	getCurPathCode (void) const
virtual SoNode *	getCurPathTail (void)
SoNode *	getNodeAppliedTo (void) const
const SoPathList *	getOriginalPathListAppliedTo (void) const
SoPath *	getPathAppliedTo (void) const
PathCode	getPathCode (int &numindices, const int *&indices)
const SoPathList *	getPathListAppliedTo (void) const
SoState *	getState (void) const
AppliedCode	getWhatAppliedTo (void) const
SbBool	hasTerminated (void) const
virtual void	invalidateState (void)
SbBool	isLastPathListAppliedTo (void) const
virtual SbBool	isOfType (SoType type) const
void	popCurPath (const PathCode prevpathcode)
void	popCurPath (void)
void	popPushCurPath (const int childindex, SoNode *node=NULL)
void	pushCurPath (const int childindex, SoNode *node=NULL)
void	pushCurPath (void)
void	switchToNodeTraversal (SoNode *node)
void	switchToPathTraversal (SoPath *path)
void	traverse (SoNode *const node)
void	usePathCode (int &numindices, const int *&indices)

Static Public Member Functions
static void	addMethod (const SoType type, SoActionMethod method)
static void	enableElement (const SoType type, const int stackindex)
static SoType	getClassTypeId (void)
static void	initClass (void)
Static Public Member Functions inherited from SoAction
static SoType	getClassTypeId (void)
static void	initClass (void)
static void	initClasses (void)
static void	nullAction (SoAction *action, SoNode *node)

Protected Member Functions
virtual void	beginTraversal (SoNode *node)
virtual const SoEnabledElementsList &	getEnabledElements (void) const
Protected Member Functions inherited from SoAction
	SoAction (void)
virtual void	endTraversal (SoNode *node)
void	setTerminated (const SbBool flag)
virtual SbBool	shouldCompactPathList (void) const

Static Protected Member Functions
static SoActionMethodList *	getClassActionMethods (void)
static SoEnabledElementsList *	getClassEnabledElements (void)
Static Protected Member Functions inherited from SoAction
static SoActionMethodList *	getClassActionMethods (void)
static SoEnabledElementsList *	getClassEnabledElements (void)

Additional Inherited Members
Public Types inherited from SoAction
enum	AppliedCode { NODE = 0 , PATH = 1 , PATH_LIST = 2 }
enum	PathCode { NO_PATH = 0 , IN_PATH = 1 , BELOW_PATH = 2 , OFF_PATH = 3 }
Protected Attributes inherited from SoAction
SoState *	state
SoActionMethodList *	traversalMethods

Detailed Description

The SoHandleEventAction class distributes user events to the scene.

This is the action used by the GUI viewer classes to pass interaction events from the window system to the nodes in the scene graph.

SoHandleEventAction also provides the functionality for tracking the object currently under the cursor, and functionality for "grabbing" the event focus.

See also

SoEvent

Constructor & Destructor Documentation

SoHandleEventAction()

SoHandleEventAction::SoHandleEventAction

(

const SbViewportRegion &

viewportregion

)

Constructor.

SoHandleEventAction needs a viewportregion to pass on to the ray pick action instance it uses for being able to track objects under the mouse cursor.

~SoHandleEventAction()

SoHandleEventAction::~SoHandleEventAction ( void )

virtual

Destructor.

Member Function Documentation

addMethod()

void SoHandleEventAction::addMethod ( const SoType type, SoActionMethod method )

static

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

beginTraversal()

void SoHandleEventAction::beginTraversal ( SoNode * node )

protectedvirtual

This virtual method is called from SoAction::apply(), and is the entry point for the actual scene graph traversal.

It can be overridden to initialize the action at traversal start, for specific initializations in the action subclasses inheriting SoAction.

Default method just calls traverse(), which any overridden implementation of the method must do too (or call SoAction::beginTraversal()) to trigger the scene graph traversal.

Reimplemented from SoAction.

enableElement()

void SoHandleEventAction::enableElement ( const SoType type, const int stackindex )

static

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

getClassActionMethods()

SoActionMethodList * SoHandleEventAction::getClassActionMethods ( void )

staticprotected

Returns list of action methods for this class. The enabledElements and methods variables are protected in the original OIV API. This is not such a good idea, since exposed static class member variables is a major grievance with regard to Win32 DLLs. This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

getClassEnabledElements()

SoEnabledElementsList * SoHandleEventAction::getClassEnabledElements ( void )

staticprotected

Returns list of enabled elements for this class. The enabledElements and methods variables are protected in the original OIV API. This is not such a good idea, since exposed static class member variables is a major grievance with regard to Win32 DLLs. This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

getClassTypeId()

SoType SoHandleEventAction::getClassTypeId ( void )

static

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

getEnabledElements()

const SoEnabledElementsList & SoHandleEventAction::getEnabledElements ( void ) const

protectedvirtual

Returns list of enabled elements.

Reimplemented from SoAction.

getEvent()

const SoEvent * SoHandleEventAction::getEvent

(

void

)

const

Returns the event this action is handling.

getGrabber()

SoNode * SoHandleEventAction::getGrabber

(

void

)

const

Returns the grabber node, or NULL if no grabber is active.

getPickedPoint()

const SoPickedPoint * SoHandleEventAction::getPickedPoint

(

void

)

Returns the SoPickedPoint information for the intersection point below the cursor.

getPickedPointList()

const SoPickedPointList & SoHandleEventAction::getPickedPointList

(

void

)

Returns a list of all intersection points below the mouse cursor.

getPickRadius()

float SoHandleEventAction::getPickRadius

(

void

)

const

Gets the pick radius for cursor tracking.

getPickRoot()

SoNode * SoHandleEventAction::getPickRoot

(

void

)

const

Returns the root node that is used by nodes that is tracking the cursor.

getTypeId()

SoType SoHandleEventAction::getTypeId ( void ) const

virtual

Returns the type identification of an object derived from a class inheriting SoAction. This is used for runtime type checking and "downward" casting.

Implements SoAction.

getViewportRegion()

const SbViewportRegion & SoHandleEventAction::getViewportRegion

(

void

)

const

Returns the viewport region this action instance is using.

Advanced Usage:

You can also get the viewport region by accessing it through its element on the traversal state. You do that the following way:

#include <Inventor/elements/SoViewportRegionElement.h>
 
  SoState * state = action->getState();
  SbViewportRegion vp = SoViewportRegionElement::get(state);

The reason for explaining this is that you can use this generic technique when you need access to state information when you can't seem to find the accessor function you need in the action implementation. You can use it to for instance retrieve the view volume information, for which there are no accessor methods:

#include <Inventor/elements/SoViewVolumeElement.h>
 
  SoState * state = action->getState();
  SbViewVolume vv = SoViewVolumeElement::get(state);

When you do this on arbitrary action instances, you need to make sure that the given element is enabled for the action before you try to use it. The relevant functions for this are SoState::isElementEnabled() and SoElement::getClassStackIndex().

initClass()

void SoHandleEventAction::initClass ( void )

static

Initializes the runtime type system for this class, and sets up the enabled elements and action method list.

isHandled()

SbBool SoHandleEventAction::isHandled

(

void

)

const

Returns whether or not the event has been handled by a node during scene graph traversal.

See also

setHandled()

releaseGrabber()

void SoHandleEventAction::releaseGrabber

(

void

)

Don't send the events to a "grabber" node anymore, use the default behavior of the action and pass them along to the scene graph again.

See also

setGrabber()

setEvent()

void SoHandleEventAction::setEvent

(

const SoEvent *

ev

)

Set the event to distribute to the nodes of the scene.

setGrabber()

void SoHandleEventAction::setGrabber

(

SoNode *

node

)

Set a node pointer which will get all future events handled by this action until releaseGrabber() is called.

Note that since later SoHandleEventAction invocations are just applied directly on the grabber node, using SoHandleEventAction methods like getCurPath() will return bogus data.

setHandled()

void SoHandleEventAction::setHandled

(

void

)

Marks the action instance as handled, hence terminates the action.

The action is only marked as handled when a node in the graph "grabs" the event this action is carrying, so the handled flag will be FALSE after traversal if no nodes wanted the event.

See also

isHandled()

setPickRadius()

void SoHandleEventAction::setPickRadius

(

const float

radiusinpixels

)

Sets the pick radius for cursor tracking.

setPickRoot()

void SoHandleEventAction::setPickRoot

(

SoNode *

node

)

Sets the root node that is used for the pick action tracking the cursor.

setViewportRegion()

void SoHandleEventAction::setViewportRegion

(

const SbViewportRegion &

newregion

)

Set a new viewport region, replacing the one passed in the constructor.

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

• SoHandleEventAction.h
• SoHandleEventAction.cpp