/*
* 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 Mar 8, 2005
*
*/
package edu.uci.ics.jung.visualization.control;
import java.awt.Cursor;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Point2D;
import edu.uci.ics.jung.visualization.Layer;
import edu.uci.ics.jung.visualization.VisualizationViewer;
import edu.uci.ics.jung.visualization.transform.LensTransformer;
import edu.uci.ics.jung.visualization.transform.MutableTransformer;
/**
* Extends TranslatingGraphMousePlugin and adds the capability
* to drag and resize the viewing
* lens in the graph view. Mouse1 in the center moves the lens,
* mouse1 on the edge resizes the lens. The default mouse button and
* modifiers can be overridden in the constructor.
*
*
* @author Tom Nelson
*/
public class LensTranslatingGraphMousePlugin extends TranslatingGraphMousePlugin
implements MouseListener, MouseMotionListener {
protected boolean dragOnLens;
protected boolean dragOnEdge;
protected double edgeOffset;
/**
* create an instance with default modifiers
*/
public LensTranslatingGraphMousePlugin() {
this(MouseEvent.BUTTON1_MASK);
}
/**
* create an instance with passed modifer value
* @param modifiers the mouse event modifier to activate this function
*/
public LensTranslatingGraphMousePlugin(int modifiers) {
super(modifiers);
}
/**
* Check the event modifiers. Set the 'down' point for later
* use. If this event satisfies the modifiers, change the cursor
* to the system 'move cursor'
* @param e the event
*/
public void mousePressed(MouseEvent e) {
VisualizationViewer vv = (VisualizationViewer)e.getSource();
MutableTransformer vt = vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.VIEW);
if(vt instanceof LensTransformer) {
vt = ((LensTransformer)vt).getDelegate();
}
Point2D p = vt.inverseTransform(e.getPoint());
boolean accepted = checkModifiers(e);
if(accepted) {
vv.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
testViewCenter(vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.LAYOUT), p);
testViewCenter(vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.VIEW), p);
vv.repaint();
}
super.mousePressed(e);
}
/**
* called to change the location of the lens
* @param transformer
* @param point
*/
private void setViewCenter(MutableTransformer transformer, Point2D point) {
if(transformer instanceof LensTransformer) {
LensTransformer ht =
(LensTransformer)transformer;
ht.setViewCenter(point);
}
}
/**
* called to change the radius of the lens
* @param transformer
* @param point
*/
private void setViewRadius(MutableTransformer transformer, Point2D point) {
if(transformer instanceof LensTransformer) {
LensTransformer ht =
(LensTransformer)transformer;
double distanceFromCenter = ht.getDistanceFromCenter(point);
ht.setViewRadius(distanceFromCenter+edgeOffset);
}
}
/**
* called to set up translating the lens center or changing the size
* @param transformer
* @param point
*/
private void testViewCenter(MutableTransformer transformer, Point2D point) {
if(transformer instanceof LensTransformer) {
LensTransformer ht =
(LensTransformer)transformer;
double distanceFromCenter = ht.getDistanceFromCenter(point);
if(distanceFromCenter < 10) {
ht.setViewCenter(point);
dragOnLens = true;
} else if(Math.abs(distanceFromCenter - ht.getViewRadius()) < 10) {
edgeOffset = ht.getViewRadius() - distanceFromCenter;
ht.setViewRadius(distanceFromCenter+edgeOffset);
dragOnEdge = true;
}
}
}
/**
* unset the 'down' point and change the cursoe back to the system
* default cursor
*/
public void mouseReleased(MouseEvent e) {
super.mouseReleased(e);
dragOnLens = false;
dragOnEdge = false;
edgeOffset = 0;
}
/**
* check the modifiers. If accepted, move or resize the lens according
* to the dragging of the mouse pointer
* @param e the event
*/
public void mouseDragged(MouseEvent e) {
VisualizationViewer vv = (VisualizationViewer)e.getSource();
MutableTransformer vt = vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.VIEW);
if(vt instanceof LensTransformer) {
vt = ((LensTransformer)vt).getDelegate();
}
Point2D p = vt.inverseTransform(e.getPoint());
boolean accepted = checkModifiers(e);
if(accepted ) {
MutableTransformer modelTransformer = vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.LAYOUT);
vv.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
if(dragOnLens) {
setViewCenter(modelTransformer, p);
setViewCenter(vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.VIEW), p);
e.consume();
vv.repaint();
} else if(dragOnEdge) {
setViewRadius(modelTransformer, p);
setViewRadius(vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.VIEW), p);
e.consume();
vv.repaint();
} else {
MutableTransformer mt = vv.getRenderContext().getMultiLayerTransformer().getTransformer(Layer.LAYOUT);
Point2D iq = vt.inverseTransform(down);
iq = mt.inverseTransform(iq);
Point2D ip = vt.inverseTransform(e.getPoint());
ip = mt.inverseTransform(ip);
float dx = (float) (ip.getX()-iq.getX());
float dy = (float) (ip.getY()-iq.getY());
modelTransformer.translate(dx, dy);
down.x = e.getX();
down.y = e.getY();
}
}
}
}