Package org.apache.batik.gvt

Class UpdateTracker

java.lang.Object

org.apache.batik.gvt.event.GraphicsNodeChangeAdapter

org.apache.batik.gvt.UpdateTracker

All Implemented Interfaces:

java.util.EventListener, GraphicsNodeChangeListener

public class UpdateTracker
extends GraphicsNodeChangeAdapter

This class tracks the changes on a GVT tree

Field Summary

Fields

Modifier and Type	Field	Description
protected static java.awt.geom.Rectangle2D	NULL_RECT

Constructor Summary

Constructors

Constructor	Description
UpdateTracker()

Method Summary

Modifier and Type	Method	Description
void	changeStarted(GraphicsNodeChangeEvent gnce)	Receives notification of a change to a GraphicsNode.
void	clear()	Clears the tracker.
java.util.List	getDirtyAreas()	Returns the list of dirty areas on GVT.
java.awt.geom.Rectangle2D	getNodeDirtyRegion(GraphicsNode gn)
java.awt.geom.Rectangle2D	getNodeDirtyRegion(GraphicsNode gn, java.awt.geom.AffineTransform at)	This returns the dirty region for gn in the coordinate system given by at.
boolean	hasChanged()	Tells whether the GVT tree has changed.

Methods inherited from class org.apache.batik.gvt.event.GraphicsNodeChangeAdapter

changeCompleted

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

NULL_RECT

protected static java.awt.geom.Rectangle2D NULL_RECT

Constructor Detail

UpdateTracker

public UpdateTracker()

Method Detail

hasChanged

public boolean hasChanged()

Tells whether the GVT tree has changed.

getDirtyAreas

public java.util.List getDirtyAreas()

Returns the list of dirty areas on GVT.

getNodeDirtyRegion

public java.awt.geom.Rectangle2D getNodeDirtyRegion(GraphicsNode gn,
                                                    java.awt.geom.AffineTransform at)

This returns the dirty region for gn in the coordinate system given by at.

Parameters:

gn - Node tree to return dirty region for.

at - Affine transform to coordinate space to accumulate dirty regions in.

getNodeDirtyRegion

public java.awt.geom.Rectangle2D getNodeDirtyRegion(GraphicsNode gn)

changeStarted

public void changeStarted(GraphicsNodeChangeEvent gnce)

Receives notification of a change to a GraphicsNode.

Specified by:

changeStarted in interface GraphicsNodeChangeListener

Overrides:

changeStarted in class GraphicsNodeChangeAdapter

Parameters:

gnce - The event object describing the GraphicsNode change.

clear

public void clear()

Clears the tracker.