Manages a list of selected objects. More...

#include <Inventor/nodes/SoSelection.h>

Inheritance diagram for SoSelection:

Public Types
enum	Policy { SINGLE, TOGGLE, SHIFT }
	Selection policy. More...
Public Member Functions
	SoSelection ()
	Creates a selection node with the default settings.
	SoSelection (int nChildren)
	Constructor that specifies the approximate number of children.
void	select (const SoPath *path)
	Select the passed path by adding it to the selection list.
void	select (SoNode *node)
	Select the passed node by creating a path to it, and adding the path to the selection list by calling select(path).
void	deselect (const SoPath *path)
	Deselect the passed path by removing it from the selection list.
void	deselect (int which)
	Deselect a path by removing it from the selection list.
void	deselect (SoNode *node)
	Deselect the passed node by creating a path to it, and removing the node from the selection list by calling deselect(path).
void	toggle (const SoPath *path)
	Toggle the selection status of the passed path em if the path is in the selection list, it is removed; if not in the list, it is added.
void	toggle (SoNode *node)
	Toggle the selection status of the passed node by creating a path to it, then calling toggle(path).
SbBool	isSelected (const SoPath *path) const
	returns TRUE if the path is selected
SbBool	isSelected (SoNode *node) const
	This convenience version of deselect will search for the first instance of the passed node under this selection node, and return whether that path is selected.
void	deselectAll ()
	Deselect all paths in the selection list, that is, clear the list.
int	getNumSelected () const
	Return the number of paths in the selection list.
const SoPathList *	getList () const
	Return the list of selected paths.
SoPath *	getPath (int index) const
	Return the `ith` path in the selection list.
SoPath *	operator[] (int i) const
	[] indexes into the selection list
void	addSelectionCallback (SoSelectionPathCB f, void userData=NULL)
	The selection callbacks are invoked every time an object is selected, whether it be from user interaction or from method call.
void	removeSelectionCallback (SoSelectionPathCB f, void userData=NULL)
	Remove selection callback.
void	addDeselectionCallback (SoSelectionPathCB f, void userData=NULL)
	The deselection callbacks are invoked every time an object is deselected, whether it be from user interaction or from method call.
void	removeDeselectionCallback (SoSelectionPathCB f, void userData=NULL)
	Remove deselection callback.
void	addStartCallback (SoSelectionClassCB f, void userData=NULL)
	The start callbacks are invoked when the user has initiated an interactive change to the selection list (by picking objects).
void	removeStartCallback (SoSelectionClassCB f, void userData=NULL)
	Remove the start callback.
void	addFinishCallback (SoSelectionClassCB f, void userData=NULL)
	The finish callbacks are invoked when the user has finished interactively changing the selection list (by picking objects).
void	removeFinishCallback (SoSelectionClassCB f, void userData=NULL)
	Remove finish callback.
void	setPickFilterCallback (SoSelectionPickCB f, void userData=NULL, SbBool callOnlyIfSelectable=TRUE)
	The pick filter callback is invoked when a pick has occurred and the selection node is about to change the selection list.
void	setPickMatching (SbBool pickTwice)
	SoSelection will pick once on mouse down and once on mouse up, and make sure the picks match before changing the selection list.
SbBool	isPickMatching () const
	Returns if pick matching is on.
SbBool	getPickMatching () const
	Returns if pick matching is on.
void	addChangeCallback (SoSelectionClassCB f, void userData=NULL)
	Selection notify callbacks - invoked whenever the selection changes.
void	removeChangeCallback (SoSelectionClassCB f, void userData=NULL)
Static Public Member Functions
static void	initClass ()
	Internal:
Public Attributes
Fields
SoSFEnum	policy
	Selection policy that is followed in response to user interaction.
Protected Member Functions
void	invokeSelectionPolicy (SoPath *path, SbBool shiftDown)
	Selection policies (shiftSelection is a combination of these) invokeSelectionPolicy() is called from handleEvent() - for a customized selection policy, either derive a class and write a new handleEvent() method, or use an SoEventCallback node placed such that it receives events before the selection node.
void	performSingleSelection (SoPath *path)
void	performToggleSelection (SoPath *path)
SoPath *	copyFromThis (const SoPath *path) const
	This copies the path so the copy is rooted by 'this'.
void	addPath (SoPath *path)
	addPath() assumes the path is rooted by 'this'
void	removePath (int which)
int	findPath (const SoPath *path) const
	This locates path in the selection list.
virtual void	handleEvent (SoHandleEventAction *action)
	Traversal routine for SoHandleEventAction - this will call action->setHandled() if the event is handled.
	~SoSelection ()
	Destructor removes everything from the list.
Protected Attributes
SoPathList	selectionList
	List of paths of selected objects.
SoCallbackList *	selCBList
	Selection callback lists.
SoCallbackList *	deselCBList
SoCallbackList *	startCBList
SoCallbackList *	finishCBList
SoSelectionPickCB *	pickCBFunc
	Pick filter is a single callback function, not a list.
void *	pickCBData
SbBool	callPickCBOnlyIfSelectable
SoCallbackList *	changeCBList
	Change callbacks.
SoPath *	mouseDownPickPath
	Mouse down picked path.
SbBool	pickMatching

Detailed Description

SoSelection defines a node which can be inserted into a scene graph and will generate and manage a selection list from picks on any node in the subgraph below it. Nodes are selected based on a current selection policy. Callback functions report back to the application when a path has been selected or deselected. The selection list can also be managed programmatically.

When handling events, SoSelection makes sure that the mouse release event was over the same object as the mouse press event before changing the list of selected objects. This allows users to mouse down on an object, change their mind and move the cursor off the object, then release the mouse button without altering the selection.

The selection can be highlighted automatically through the SoQtRenderArea, or the application can provide custom highlights. Please see the chapter "Creating a Selection Highlight Style" in the Inventor Toolmaker.

File Format/Default

Selection {
  renderCaching AUTO
  boundingBoxCaching AUTO
  renderCulling AUTO
  pickCulling AUTO
  policy SHIFT
}

See Also

: SoEventCallback, SoQtRenderArea, SoBoxHighlightRenderAction, SoLineHighlightRenderAction

Definition at line 125 of file SoSelection.h.

Member Enumeration Documentation

enum SoSelection::Policy

---------------- Default selection policy is SoSelection::SHIFT.

Enumerator:

SINGLE

left mouse pick on object clears selection, then selects object.

left mouse pick on nothing clears selection. only one object may be selected at a time.

TOGGLE

left mouse pick on object toggles its selection status.

left mouse pick on nothing does nothing. multiple objects may be selected.

SHIFT

when shift key is down, selection policy is TOGGLE.

when shift key is up, selection policy is SINGLE. multiple objects may be selected.

Definition at line 142 of file SoSelection.h.

Constructor & Destructor Documentation

SoSelection::SoSelection ( )

SoSelection::SoSelection ( int nChildren )

SoSelection::~SoSelection ( ) [protected]

Member Function Documentation

void SoSelection::addChangeCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

Used by the render area to redraw for selection highlighting.

void SoSelection::addDeselectionCallback	(	SoSelectionPathCB *	f,
		void *	userData = `NULL`
	)

This is invoked after the object has been removed from the selection list.

void SoSelection::addFinishCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

This was preceded by an invocation of each start callback, and invocations of the select and/or deselect callbacks. The finish callbacks are not called when the selection list is changed programmatically.

void SoSelection::addPath ( SoPath * path ) [protected]

void SoSelection::addSelectionCallback	(	SoSelectionPathCB *	f,
		void *	userData = `NULL`
	)

The callbacks are invoked after the object has been added to the selection list.

void SoSelection::addStartCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

This will be followed by invocations of the select and/or deselect callbacks, finally followed by each finish callback. A start callback can be used, for instance, to save the current selection for later restoration (e.g. undo/redo). The start callbacks are not called when the selection list is changed programmatically.

SoPath* SoSelection::copyFromThis ( const SoPath * path ) const [protected]

Returns NULL if 'this' not found in the passed path.

void SoSelection::deselect ( int which )

The argument which specifies which path in the list to be removed.

void SoSelection::deselect ( SoNode * node )

If there is more than one instance of node beneath the selection node, the created path will be the first instance found.

void SoSelection::deselect ( const SoPath * path )

void SoSelection::deselectAll ( )

int SoSelection::findPath ( const SoPath * path ) const [protected]

The head of this path does not necessarily have to be 'this'.

const SoPathList* SoSelection::getList ( ) const [inline]

Definition at line 221 of file SoSelection.h.

int SoSelection::getNumSelected ( ) const [inline]

Definition at line 219 of file SoSelection.h.

SoPath* SoSelection::getPath ( int index ) const

SbBool SoSelection::getPickMatching ( ) const [inline]

Definition at line 331 of file SoSelection.h.

virtual void SoSelection::handleEvent ( SoHandleEventAction * action ) [protected, virtual]

Reimplemented from SoSeparator.

static void SoSelection::initClass ( ) [static]

Reimplemented from SoSeparator.

void SoSelection::invokeSelectionPolicy	(	SoPath *	path,
		SbBool	shiftDown
	)		`[protected]`

SbBool SoSelection::isPickMatching ( ) const [inline]

Definition at line 329 of file SoSelection.h.

SbBool SoSelection::isSelected ( const SoPath * path ) const

SbBool SoSelection::isSelected ( SoNode * node ) const

SoPath* SoSelection::operator[] ( int i ) const [inline]

Definition at line 226 of file SoSelection.h.

void SoSelection::performSingleSelection ( SoPath * path ) [protected]

void SoSelection::performToggleSelection ( SoPath * path ) [protected]

void SoSelection::removeChangeCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

void SoSelection::removeDeselectionCallback	(	SoSelectionPathCB *	f,
		void *	userData = `NULL`
	)

void SoSelection::removeFinishCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

void SoSelection::removePath ( int which ) [protected]

void SoSelection::removeSelectionCallback	(	SoSelectionPathCB *	f,
		void *	userData = `NULL`
	)

void SoSelection::removeStartCallback	(	SoSelectionClassCB *	f,
		void *	userData = `NULL`
	)

void SoSelection::select ( SoNode * node )

If there is more than one instance of node beneath the selection node, the created path will be the first instance found.

void SoSelection::select ( const SoPath * path )

The selection node must lie in the path. The path is copied and truncated such that the selection node is the head of the path. If the selection node does not lie in the path, the selection list remains unchanged. This method ignores the current selection policy.

void SoSelection::setPickFilterCallback	(	SoSelectionPickCB *	f,
		void *	userData = `NULL`,
		SbBool	callOnlyIfSelectable = `TRUE`
	)

The callback function returns the path that the selection node should use when selecting and deselecting. If no pick callback is registered (the default), the selection node will use the path returned by SoPickedPoint::getPath() on the picked point associated with the event being processed. The returned path should not be ref'd - selection will ref() and unref() it. (See SoPath::unrefNoDelete().)

Note that a picked object may or may not be a child of the selection node. A selection node will only select paths that pass through it. Possible return values from the callback:

[a] NULL em selection behaves as if nothing was picked (i.e. for SINGLE and SHIFT policies, this clears the selection list). Handle event action traversal halts.

[b] Path em this path will be selected/deselected according to the selection policy (it must lie under the selection node). Handle event action traversal halts.

[c] Path containing only the selection node em apply the selection policy as if nothing was picked. Handle event action traversal continues.

[d] Path not passing through the selection node em selection ignores this pick event and no change is made to the selection list. Handle event action traversal continues.

A simple way to tell selection to ignore the pick is to return an SoPath with no nodes in it. (i.e. return new SoPath;) Selection will always ref the path returned by the callback, make a copy of the path, then unref the path.

The callOnlyIfSelectable argument, when set to TRUE, means the pick callback function will only be invoked on picks which pass through the selection node. When FALSE, all picks will be passed to the callback whether they pass through the selection or not.

void SoSelection::setPickMatching ( SbBool pickTwice ) [inline]

This allows the user to pick down on an object, change their mind and drag off the object, release the mouse button and not affect the selection. Pass TRUE to enable this behavior. Pass FALSE to disable this, meaning whatever is picked on a mouse release is added to/removed from the selection list. Default is pick-matching on.

Definition at line 327 of file SoSelection.h.

void SoSelection::toggle ( const SoPath * path )