util.ModSpringLayout1.java Source code

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/*
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 * and open the template in the editor.
 */
package util;

/**
 *
 * @author Knacky
 */
/*
 * 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.
 */
import edu.uci.ics.jung.algorithms.layout.AbstractLayout;
//import edu.uci.ics.jung.algorithms.layout.SpringLayout.LengthFunction;
import java.awt.Dimension;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.geom.Point2D;
import java.util.ConcurrentModificationException;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.collections15.Factory;
import org.apache.commons.collections15.Transformer;
import org.apache.commons.collections15.map.LazyMap;

import edu.uci.ics.jung.algorithms.util.IterativeContext;
import edu.uci.ics.jung.algorithms.layout.util.RandomLocationTransformer;
import edu.uci.ics.jung.graph.Graph;

/**
 * The SpringLayout package represents a visualization of a set of nodes. The
 * SpringLayout, which is initialized with a Graph, assigns X/Y locations to
 * each node. When called <code>relax()</code>, the SpringLayout moves the
 * visualization forward one step.
 * 
 * @author Danyel Fisher
 * @author Joshua O'Madadhain
 */
public class ModSpringLayout1<V, E> extends AbstractLayout<V, E> implements IterativeContext {

    protected double stretch = 0.70;
    protected Transformer<E, Integer> lengthFunction;
    protected int repulsion_range = 100;
    protected double force_multiplier = 1.0 / 3.0;
    Map<E, SpringEdgeData<E>> springEdgeData = LazyMap.decorate(new HashMap<E, SpringEdgeData<E>>(),
            new Transformer<E, SpringEdgeData<E>>() {

                public SpringEdgeData<E> transform(E e) {
                    return new SpringEdgeData<E>(e);
                }
            });
    Map<V, SpringVertexData> springVertexData = LazyMap.decorate(new HashMap<V, SpringVertexData>(),
            new Factory<SpringVertexData>() {

                public SpringVertexData create() {
                    return new SpringVertexData();
                }
            });

    /**
     * Constructor for a SpringLayout for a raw graph with associated
     * dimension--the input knows how big the graph is. Defaults to the unit
     * length function.
     */
    public ModSpringLayout1(Graph<V, E> g) {
        this(g, UNITLENGTHFUNCTION);
    }

    /**
     * Constructor for a SpringLayout for a raw graph with associated component.
     * 
     * @param g
     *            the input Graph
     * @param f
     *            the length function
     */
    public ModSpringLayout1(Graph<V, E> g, Transformer<E, Integer> f) {
        super(g);
        this.lengthFunction = f;
    }

    /**
     * @return the current value for the stretch parameter
     * @see #setStretch(double)
     */
    public double getStretch() {
        return stretch;
    }

    /* (non-Javadoc)
     * @see edu.uci.ics.jung.visualization.layout.AbstractLayout#setSize(java.awt.Dimension)
     */
    @Override
    public void setSize(Dimension size) {
        if (initialized == false) {
            setInitializer(new RandomLocationTransformer<V>(size));
        }
        super.setSize(size);
    }

    /**
     * <p>Sets the stretch parameter for this instance.  This value 
     * specifies how much the degrees of an edge's incident vertices
     * should influence how easily the endpoints of that edge
     * can move (that is, that edge's tendency to change its length).</p>
     * 
     * <p>The default value is 0.70.  Positive values less than 1 cause
     * high-degree vertices to move less than low-degree vertices, and 
     * values > 1 cause high-degree vertices to move more than 
     * low-degree vertices.  Negative values will have unpredictable
     * and inconsistent results.</p>
     * @param stretch
     */
    public void setStretch(double stretch) {
        this.stretch = stretch;
    }

    /**
     * @return the current value for the node repulsion range
     * @see #setRepulsionRange(int)
     */
    public int getRepulsionRange() {
        return repulsion_range;
    }

    /**
     * Sets the node repulsion range (in drawing area units) for this instance.  
     * Outside this range, nodes do not repel each other.  The default value 
     * is 100.  Negative values are treated as their positive equivalents.
     * @param range
     */
    public void setRepulsionRange(int range) {
        this.repulsion_range = range;
    }

    /**
     * @return the current value for the edge length force multiplier
     * @see #setForceMultiplier(double)
     */
    public double getForceMultiplier() {
        return force_multiplier;
    }

    /**
     * Sets the force multiplier for this instance.  This value is used to 
     * specify how strongly an edge "wants" to be its default length
     * (higher values indicate a greater attraction for the default length),
     * which affects how much its endpoints move at each timestep.
     * The default value is 1/3.  A value of 0 turns off any attempt by the
     * layout to cause edges to conform to the default length.  Negative
     * values cause long edges to get longer and short edges to get shorter; use
     * at your own risk.
     */
    public void setForceMultiplier(double force) {
        this.force_multiplier = force;
    }

    public void initialize() {
        Graph<V, E> graph = getGraph();
        Dimension d = getSize();
        if (graph != null && d != null) {

            try {
                for (E e : graph.getEdges()) {
                    SpringEdgeData<E> sed = getSpringEdgeData(e);
                    calcEdgeLength(sed, lengthFunction);
                }
            } catch (ConcurrentModificationException cme) {
                initialize();
            }
        }
    }

    /* ------------------------- */
    protected void calcEdgeLength(SpringEdgeData<E> sed, Transformer<E, Integer> f) {
        //        sed.length = f.getLength(sed.e);
        sed.length = f.transform(sed.e);
    }

    /* ------------------------- */
    /**
     * Relaxation step. Moves all nodes a smidge.
     */
    public void step() {
        try {
            for (V v : getGraph().getVertices()) {
                SpringVertexData svd = getSpringVertexData(v);
                if (svd == null) {
                    continue;
                }
                svd.dx /= 4;
                svd.dy /= 4;
                svd.edgedx = svd.edgedy = 0;
                svd.repulsiondx = svd.repulsiondy = 0;
            }
        } catch (ConcurrentModificationException cme) {
            step();
        }

        relaxEdges();
        calculateRepulsion();
        moveNodes();
        //       this.fireStateChanged();
    }

    protected V getAVertex(E e) {

        return getGraph().getIncidentVertices(e).iterator().next();
    }

    protected void relaxEdges() {
        try {
            for (E e : getGraph().getEdges()) {

                V v1 = getAVertex(e);
                V v2 = getGraph().getOpposite(v1, e);

                Point2D p1 = transform(v1);
                Point2D p2 = transform(v2);
                if (p1 == null || p2 == null) {
                    continue;
                }
                double vx = p1.getX() - p2.getX();
                double vy = p1.getY() - p2.getY();
                double len = Math.sqrt(vx * vx + vy * vy);

                SpringEdgeData<E> sed = getSpringEdgeData(e);
                if (sed == null) {
                    continue;
                }
                double desiredLen = sed.length;

                // round from zero, if needed [zero would be Bad.].
                len = (len == 0) ? .0001 : len;

                double f = force_multiplier * (desiredLen - len) / len;

                f = f * Math.pow(stretch, (getGraph().degree(v1) + getGraph().degree(v2) - 2));

                // the actual movement distance 'dx' is the force multiplied by the
                // distance to go.
                double dx = f * vx;
                double dy = f * vy;
                SpringVertexData v1D, v2D;
                v1D = getSpringVertexData(v1);
                v2D = getSpringVertexData(v2);

                sed.f = f;

                v1D.edgedx += dx;
                v1D.edgedy += dy;
                v2D.edgedx += -dx;
                v2D.edgedy += -dy;
            }
        } catch (ConcurrentModificationException cme) {
            relaxEdges();
        }
    }

    protected void calculateRepulsion() {
        try {
            for (V v : getGraph().getVertices()) {
                if (isLocked(v)) {
                    continue;
                }

                SpringVertexData svd = getSpringVertexData(v);
                if (svd == null) {
                    continue;
                }
                double dx = 0, dy = 0;

                for (V v2 : getGraph().getVertices()) {
                    if (v == v2) {
                        continue;
                    }
                    Point2D p = transform(v);
                    Point2D p2 = transform(v2);
                    if (p == null || p2 == null) {
                        continue;
                    }
                    double vx = p.getX() - p2.getX();
                    double vy = p.getY() - p2.getY();
                    double distance = vx * vx + vy * vy;
                    if (distance == 0) {
                        dx += Math.random();
                        dy += Math.random();
                    } else if (distance < repulsion_range * repulsion_range) {
                        double factor = 1;
                        dx += factor * vx / Math.pow(distance, 2);
                        dy += factor * vy / Math.pow(distance, 2);
                    }
                }
                double dlen = dx * dx + dy * dy;
                if (dlen > 0) {
                    dlen = Math.sqrt(dlen) / 2;
                    svd.repulsiondx += dx / dlen;
                    svd.repulsiondy += dy / dlen;
                }
            }
        } catch (ConcurrentModificationException cme) {
            calculateRepulsion();
        }
    }

    protected void moveNodes() {

        synchronized (getSize()) {
            try {
                for (V v : getGraph().getVertices()) {
                    if (isLocked(v)) {
                        continue;
                    }
                    SpringVertexData vd = getSpringVertexData(v);
                    if (vd == null) {
                        continue;
                    }
                    Point2D xyd = transform(v);

                    vd.dx += vd.repulsiondx + vd.edgedx;
                    vd.dy += vd.repulsiondy + vd.edgedy;

                    // keeps nodes from moving any faster than 5 per time unit
                    xyd.setLocation(xyd.getX() + Math.max(-5, Math.min(5, vd.dx)),
                            xyd.getY() + Math.max(-5, Math.min(5, vd.dy)));

                    Dimension d = getSize();
                    int width = d.width;
                    int height = d.height;

                    if (xyd.getX() < 0) {
                        xyd.setLocation(0, xyd.getY());//                     setX(0);
                    } else if (xyd.getX() > width) {
                        xyd.setLocation(width, xyd.getY()); //setX(width);
                    }
                    if (xyd.getY() < 0) {
                        xyd.setLocation(xyd.getX(), 0);//setY(0);
                    } else if (xyd.getY() > height) {
                        xyd.setLocation(xyd.getX(), height); //setY(height);
                    }

                }
            } catch (ConcurrentModificationException cme) {
                moveNodes();
            }
        }
    }

    public SpringVertexData getSpringVertexData(V v) {
        return springVertexData.get(v);
    }

    public SpringEdgeData<E> getSpringEdgeData(E e) {
        return springEdgeData.get(e);
    }

    public double getLength(E e) {
        return springEdgeData.get(e).length;
    }

    /**
     * Returns all edges as the same length: the input value
     * @author danyelf
     */
    public static final class UnitLengthFunction<E> implements Transformer<E, Double> {

        int length;

        public UnitLengthFunction(int length) {
            this.length = length;
        }

        //        public double getLength(E e) {
        //            return length;
        //        }
        public Double transform(E e) {
            return (double) length;
        }
    }

    public static final Transformer UNITLENGTHFUNCTION = new UnitLengthFunction(30);

    /* ---------------User Data------------------ */
    protected static class SpringVertexData {

        public double edgedx;
        public double edgedy;
        public double repulsiondx;
        public double repulsiondy;

        public SpringVertexData() {
        }

        /** movement speed, x */
        public double dx;
        /** movement speed, y */
        public double dy;
    }

    protected static class SpringEdgeData<E> {

        public double f;

        public SpringEdgeData(E e) {
            this.e = e;
        }

        E e;
        double length;
    }

    /* ---------------Resize handler------------------ */
    public class SpringDimensionChecker extends ComponentAdapter {

        @Override
        public void componentResized(ComponentEvent e) {
            setSize(e.getComponent().getSize());
        }
    }

    /**
     * This one is an incremental visualization
     */
    public boolean isIncremental() {
        return true;
    }

    /**
     * For now, we pretend it never finishes.
     */
    public boolean done() {
        return false;
    }

    public void reset() {
        // no counter, do nothing.
        //      locations.clear();
        //      initialize();
    }

    public Transformer<E, Integer> getLengthFunction() {
        return lengthFunction;
    }

    public void setLengthFunction(Transformer<E, Integer> lengthFunction) {
        this.lengthFunction = lengthFunction;
    }
}