/* $Id: ClassdiagramInheritanceEdge.java 17863 2010-01-12 20:07:22Z linus $
*****************************************************************************
* Copyright (c) 2009 Contributors - see below
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* linus
*****************************************************************************
*
* Some portions of this file was previously release using the BSD License:
*/
// Copyright (c) 1996-2007 The Regents of the University of California. All
// Rights Reserved. Permission to use, copy, modify, and distribute this
// software and its documentation without fee, and without a written
// agreement is hereby granted, provided that the above copyright notice
// and this paragraph appear in all copies. This software program and
// documentation are copyrighted by The Regents of the University of
// California. The software program and documentation are supplied "AS
// IS", without any accompanying services from The Regents. The Regents
// does not warrant that the operation of the program will be
// uninterrupted or error-free. The end-user understands that the program
// was developed for research purposes and is advised not to rely
// exclusively on the program for any reason. IN NO EVENT SHALL THE
// UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
// SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
// ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
// THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
// PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
// CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT,
// UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
package org.argouml.uml.diagram.static_structure.layout;
import org.apache.log4j.Logger;
import org.tigris.gef.presentation.Fig;
import org.tigris.gef.presentation.FigEdge;
/**
*
* @author mkl
*/
public abstract class ClassdiagramInheritanceEdge extends ClassdiagramEdge {
private static final Logger LOG = Logger
.getLogger(ClassdiagramInheritanceEdge.class);
/**
* The largest difference that we consider equivalent to zero
*/
private static final int EPSILON = 5;
/**
* The figures which are connected by this edge
*/
private Fig high, low;
/**
* Offset used to distribute the lines
*/
private int offset;
/**
* Constructor.
*
* @param edge the fig edge
*/
public ClassdiagramInheritanceEdge(FigEdge edge) {
super(edge);
// calculate the higher and lower Figs
high = getDestFigNode();
low = getSourceFigNode();
offset = 0;
}
/**
* @return the vertical offset
*/
public int getVerticalOffset() {
return (getVGap() / 2) - 10 + getOffset();
}
/**
* @return the center of the high node
*/
public int getCenterHigh() {
return (int) (high.getLocation().getX() + high.getSize().width / 2)
+ getOffset();
}
/**
* @return the center of the low node
*/
public int getCenterLow() {
return (int) (low.getLocation().getX() + low.getSize().width / 2)
+ getOffset();
}
/**
* @return the gap with the node one level down
*/
public int getDownGap() {
return (int) (low.getLocation().getY() - getVerticalOffset());
}
/**
* @see org.argouml.uml.diagram.layout.LayoutedEdge#layout()
*
* Layout the edges in a way that they form a nice inheritance tree. Try to
* implement these nice zigzag lines between classes and works well when the
* row difference is one.
*
* @author Markus Klink
* @since 0.9.6
*/
public void layout() {
// now we construct the zig zag inheritance line
//getUnderlyingFig()
Fig fig = getUnderlyingFig();
int centerHigh = getCenterHigh();
int centerLow = getCenterLow();
// the amount of the "sidestep"
int difference = centerHigh - centerLow;
/*
* If center points are "close enough" we just adjust the endpoints
* of the line a little bit. Otherwise we add a jog in the middle to
* deal with the offset.
*
* TODO: Epsilon is currently fixed, but could probably be computed
* dynamically as 10% of the width of the narrowest figure or some
* other value which is visually not noticeable.
*/
if (Math.abs(difference) < EPSILON) {
fig.addPoint(centerLow + (difference / 2 + (difference % 2)),
(int) (low.getLocation().getY()));
fig.addPoint(centerHigh - (difference / 2),
high.getLocation().y + high.getSize().height);
} else {
fig.addPoint(centerLow, (int) (low.getLocation().getY()));
if (LOG.isDebugEnabled()) {
LOG.debug("Point: x: " + centerLow + " y: "
+ low.getLocation().y);
}
getUnderlyingFig().addPoint(centerHigh - difference, getDownGap());
getUnderlyingFig().addPoint(centerHigh, getDownGap());
if (LOG.isDebugEnabled()) {
LOG.debug("Point: x: " + (centerHigh - difference) + " y: "
+ getDownGap());
LOG.debug("Point: x: " + centerHigh + " y: " + getDownGap());
}
fig.addPoint(centerHigh,
high.getLocation().y + high.getSize().height);
if (LOG.isDebugEnabled()) {
LOG.debug("Point x: " + centerHigh + " y: "
+ (high.getLocation().y + high.getSize().height));
}
}
fig.setFilled(false);
getCurrentEdge().setFig(getUnderlyingFig());
// currentEdge.setBetweenNearestPoints(false);
}
/**
* Set the line-offset for this edge
*
* @param anOffset
* the offset to use for this edge
*/
public void setOffset(int anOffset) {
offset = anOffset;
}
/**
* @return Line-offset for this edge
*/
public int getOffset() {
return offset;
}
}