/*

  * Copyright (c) 2005, the JUNG Project and the Regents of the University of

  * California All rights reserved.

  *

  * This software is open-source under the BSD license; see either "license.txt"

  * or http://jung.sourceforge.net/license.txt for a description.

  *

  * Created on Jul 21, 2005

  */

 package edu.uci.ics.jung.visualization.jai;

 import javax.media.jai.PerspectiveTransform;

 import edu.uci.ics.jung.algorithms.layout.GraphElementAccessor;

 import edu.uci.ics.jung.visualization.Layer;

 import edu.uci.ics.jung.visualization.VisualizationViewer;

 import edu.uci.ics.jung.visualization.picking.LayoutLensShapePickSupport;

 /**

  * A class to make it easy to add a Perspective projection

  * to a jung graph application. See PerspectiveTransformerDemo

  * for an example of how to use it.

  * 

  * @author Tom Nelson

  *

  *

  */

 public class PerspectiveLayoutTransformSupport<V,E> extends AbstractPerspectiveTransformSupport<V,E> 

     implements PerspectiveTransformSupport {

         protected GraphElementAccessor<V,E> pickSupport;

     /**

      * @param vv the VisualizationViewer to work on

      */

     public PerspectiveLayoutTransformSupport(VisualizationViewer<V,E> vv) {

         super(vv);

         this.perspectiveTransformer = 

             new PerspectiveShapeTransformer(new PerspectiveTransform(), 

                             vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.LAYOUT));

         this.pickSupport = vv.getPickSupport();

    }

     public void activate() {

         lens = new Lens(perspectiveTransformer, vv.getSize());

         vv.getRenderContext().setPickSupport(new LayoutLensShapePickSupport<V,E>(vv));

         vv.getRenderContext().getMultiLayerTransformer().setTransformer(Layer.LAYOUT, perspectiveTransformer);

         vv.addPreRenderPaintable(lens);

         vv.setToolTipText(instructions);

         vv.repaint();

     }

     public void deactivate() {

         vv.getRenderContext().setPickSupport(pickSupport);

         if(perspectiveTransformer != null) {

             vv.removePreRenderPaintable(lens);

             vv.getRenderContext().getMultiLayerTransformer().setTransformer(Layer.LAYOUT, perspectiveTransformer.getDelegate());

         }

         vv.setToolTipText(defaultToolTipText);

         vv.repaint();

     }

 }