org.apache.batik.gvt
Class UpdateTracker

java.lang.Object
  extended by org.apache.batik.gvt.event.GraphicsNodeChangeAdapter
      extended by org.apache.batik.gvt.UpdateTracker
All Implemented Interfaces:
EventListener, GraphicsNodeChangeListener

public class UpdateTracker
extends GraphicsNodeChangeAdapter

This class tracks the changes on a GVT tree


Field Summary
protected static Rectangle2D NULL_RECT
           
 
Constructor Summary
UpdateTracker()
           
 
Method Summary
 void changeStarted(GraphicsNodeChangeEvent gnce)
          Receives notification of a change to a GraphicsNode.
 void clear()
          Clears the tracker.
 List getDirtyAreas()
          Returns the list of dirty areas on GVT.
 Rectangle2D getNodeDirtyRegion(GraphicsNode gn)
           
 Rectangle2D getNodeDirtyRegion(GraphicsNode gn, 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 Rectangle2D NULL_RECT
Constructor Detail

UpdateTracker

public UpdateTracker()
Method Detail

hasChanged

public boolean hasChanged()
Tells whether the GVT tree has changed.


getDirtyAreas

public List getDirtyAreas()
Returns the list of dirty areas on GVT.


getNodeDirtyRegion

public Rectangle2D getNodeDirtyRegion(GraphicsNode gn,
                                      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 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.



Copyright © 2008 Apache Software Foundation. All Rights Reserved.