edu.uci.ics.jung.algorithms.layout.FRLayout2 Maven / Gradle / Ivy
/*
* Copyright (c) 2003, 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.
*/
package edu.uci.ics.jung.algorithms.layout;
import java.awt.Dimension;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.util.ConcurrentModificationException;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.collections15.Factory;
import org.apache.commons.collections15.map.LazyMap;
import edu.uci.ics.jung.algorithms.layout.util.RandomLocationTransformer;
import edu.uci.ics.jung.algorithms.util.IterativeContext;
import edu.uci.ics.jung.graph.Graph;
import edu.uci.ics.jung.graph.util.Pair;
/**
* Implements the Fruchterman-Reingold force-directed algorithm for node layout.
* This is an experimental attempt at optimizing {@code FRLayout}; if it is successful
* it will be folded back into {@code FRLayout} (and this class will disappear).
*
* Behavior is determined by the following settable parameters:
*
* attraction multiplier: how much edges try to keep their vertices together
* repulsion multiplier: how much vertices try to push each other apart
* maximum iterations: how many iterations this algorithm will use before stopping
*
* Each of the first two defaults to 0.75; the maximum number of iterations defaults to 700.
*
* @see "Fruchterman and Reingold, 'Graph Drawing by Force-directed Placement'"
* @see http://i11www.ilkd.uni-karlsruhe.de/teaching/SS_04/visualisierung/papers/fruchterman91graph.pdf
*
* @author Tom Nelson
* @author Scott White, Yan-Biao Boey, Danyel Fisher
*/
public class FRLayout2 extends AbstractLayout implements IterativeContext {
private double forceConstant;
private double temperature;
private int currentIteration;
private int maxIterations = 700;
private Map frVertexData =
LazyMap.decorate(new HashMap(), new Factory() {
public Point2D create() {
return new Point2D.Double();
}});
private double attraction_multiplier = 0.75;
private double attraction_constant;
private double repulsion_multiplier = 0.75;
private double repulsion_constant;
private double max_dimension;
private Rectangle2D innerBounds = new Rectangle2D.Double();
private boolean checked = false;
/**
* Creates an instance for the specified graph.
*/
public FRLayout2(Graph g) {
super(g);
}
/**
* Creates an instance of size {@code d} for the specified graph.
*/
public FRLayout2(Graph g, Dimension d) {
super(g, new RandomLocationTransformer(d), d);
max_dimension = Math.max(d.height, d.width);
initialize();
}
@Override
public void setSize(Dimension size) {
if(initialized == false)
setInitializer(new RandomLocationTransformer(size));
super.setSize(size);
double t = size.width/50.0;
innerBounds.setFrameFromDiagonal(t,t,size.width-t,size.height-t);
max_dimension = Math.max(size.height, size.width);
}
/**
* Sets the attraction multiplier.
*/
public void setAttractionMultiplier(double attraction) {
this.attraction_multiplier = attraction;
}
/**
* Sets the repulsion multiplier.
*/
public void setRepulsionMultiplier(double repulsion) {
this.repulsion_multiplier = repulsion;
}
public void reset() {
doInit();
}
public void initialize() {
doInit();
}
private void doInit() {
Graph graph = getGraph();
Dimension d = getSize();
if(graph != null && d != null) {
currentIteration = 0;
temperature = d.getWidth() / 10;
forceConstant =
Math
.sqrt(d.getHeight()
* d.getWidth()
/ graph.getVertexCount());
attraction_constant = attraction_multiplier * forceConstant;
repulsion_constant = repulsion_multiplier * forceConstant;
}
}
private double EPSILON = 0.000001D;
/**
* Moves the iteration forward one notch, calculation attraction and
* repulsion between vertices and edges and cooling the temperature.
*/
public synchronized void step() {
currentIteration++;
/**
* Calculate repulsion
*/
while(true) {
try {
for(V v1 : getGraph().getVertices()) {
calcRepulsion(v1);
}
break;
} catch(ConcurrentModificationException cme) {}
}
/**
* Calculate attraction
*/
while(true) {
try {
for(E e : getGraph().getEdges()) {
calcAttraction(e);
}
break;
} catch(ConcurrentModificationException cme) {}
}
while(true) {
try {
for(V v : getGraph().getVertices()) {
if (isLocked(v)) continue;
calcPositions(v);
}
break;
} catch(ConcurrentModificationException cme) {}
}
cool();
}
protected synchronized void calcPositions(V v) {
Point2D fvd = this.frVertexData.get(v);
if(fvd == null) return;
Point2D xyd = transform(v);
double deltaLength = Math.max(EPSILON,
Math.sqrt(fvd.getX()*fvd.getX()+fvd.getY()*fvd.getY()));
double newXDisp = fvd.getX() / deltaLength
* Math.min(deltaLength, temperature);
assert Double.isNaN(newXDisp) == false : "Unexpected mathematical result in FRLayout:calcPositions [xdisp]";
double newYDisp = fvd.getY() / deltaLength
* Math.min(deltaLength, temperature);
double newX = xyd.getX()+Math.max(-5, Math.min(5,newXDisp));
double newY = xyd.getY()+Math.max(-5, Math.min(5,newYDisp));
newX = Math.max(innerBounds.getMinX(), Math.min(newX, innerBounds.getMaxX()));
newY = Math.max(innerBounds.getMinY(), Math.min(newY, innerBounds.getMaxY()));
xyd.setLocation(newX, newY);
}
protected void calcAttraction(E e) {
Pair endpoints = getGraph().getEndpoints(e);
V v1 = endpoints.getFirst();
V v2 = endpoints.getSecond();
boolean v1_locked = isLocked(v1);
boolean v2_locked = isLocked(v2);
if(v1_locked && v2_locked) {
// both locked, do nothing
return;
}
Point2D p1 = transform(v1);
Point2D p2 = transform(v2);
if(p1 == null || p2 == null) return;
double xDelta = p1.getX() - p2.getX();
double yDelta = p1.getY() - p2.getY();
double deltaLength = Math.max(EPSILON, p1.distance(p2));
double force = deltaLength / attraction_constant;
assert Double.isNaN(force) == false : "Unexpected mathematical result in FRLayout:calcPositions [force]";
double dx = xDelta * force;
double dy = yDelta * force;
Point2D fvd1 = frVertexData.get(v1);
Point2D fvd2 = frVertexData.get(v2);
if(v2_locked) {
// double the offset for v1, as v2 will not be moving in
// the opposite direction
fvd1.setLocation(fvd1.getX()-2*dx, fvd1.getY()-2*dy);
} else {
fvd1.setLocation(fvd1.getX()-dx, fvd1.getY()-dy);
}
if(v1_locked) {
// double the offset for v2, as v1 will not be moving in
// the opposite direction
fvd2.setLocation(fvd2.getX()+2*dx, fvd2.getY()+2*dy);
} else {
fvd2.setLocation(fvd2.getX()+dx, fvd2.getY()+dy);
}
}
protected void calcRepulsion(V v1) {
Point2D fvd1 = frVertexData.get(v1);
if(fvd1 == null) return;
fvd1.setLocation(0, 0);
boolean v1_locked = isLocked(v1);
try {
for(V v2 : getGraph().getVertices()) {
boolean v2_locked = isLocked(v2);
if (v1_locked && v2_locked) continue;
if (v1 != v2) {
Point2D p1 = transform(v1);
Point2D p2 = transform(v2);
if(p1 == null || p2 == null) continue;
double xDelta = p1.getX() - p2.getX();
double yDelta = p1.getY() - p2.getY();
double deltaLength = Math.max(EPSILON, p1.distanceSq(p2));
double force = (repulsion_constant * repulsion_constant);// / deltaLength;
double forceOverDeltaLength = force / deltaLength;
assert Double.isNaN(force) == false : "Unexpected mathematical result in FRLayout:calcPositions [repulsion]";
if(v2_locked) {
// double the offset for v1, as v2 will not be moving in
// the opposite direction
fvd1.setLocation(fvd1.getX()+2 * xDelta * forceOverDeltaLength,
fvd1.getY()+ 2 * yDelta * forceOverDeltaLength);
} else {
fvd1.setLocation(fvd1.getX()+xDelta * forceOverDeltaLength,
fvd1.getY()+yDelta * forceOverDeltaLength);
}
}
}
} catch(ConcurrentModificationException cme) {
calcRepulsion(v1);
}
}
private void cool() {
temperature *= (1.0 - currentIteration / (double) maxIterations);
}
/**
* Sets the maximum number of iterations.
*/
public void setMaxIterations(int maxIterations) {
this.maxIterations = maxIterations;
}
/**
* This one is an incremental visualization.
*/
public boolean isIncremental() {
return true;
}
/**
* Returns true once the current iteration has passed the maximum count,
* MAX_ITERATIONS.
*/
public boolean done() {
if (currentIteration > maxIterations || temperature < 1.0/max_dimension) {
if (!checked)
{
// System.out.println("current iteration: " + currentIteration);
// System.out.println("temperature: " + temperature);
checked = true;
}
return true;
}
return false;
}
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