AbstractColorTransformer.java

/*
Copyright 2008-2010 Gephi
Authors : Mathieu Bastian, Mathieu Jacomy, Julian Bilcke
Website : http://www.gephi.org

This file is part of Gephi.

DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

Copyright 2011 Gephi Consortium. All rights reserved.

The contents of this file are subject to the terms of either the GNU
General Public License Version 3 only ("GPL") or the Common
Development and Distribution License("CDDL") (collectively, the
"License"). You may not use this file except in compliance with the
License. You can obtain a copy of the License at
http://gephi.org/about/legal/license-notice/
or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
specific language governing permissions and limitations under the
License.  When distributing the software, include this License Header
Notice in each file and include the License files at
/cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the
License Header, with the fields enclosed by brackets [] replaced by
your own identifying information:
"Portions Copyrighted [year] [name of copyright owner]"

If you wish your version of this file to be governed by only the CDDL
or only the GPL Version 3, indicate your decision by adding
"[Contributor] elects to include this software in this distribution
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your version of this file under either the CDDL, the GPL Version 3 or
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However, if you add GPL Version 3 code and therefore, elected the GPL
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Contributor(s):

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 */
package org.gephi.ranking.plugin.transformer;

import java.awt.Color;
import java.io.Serializable;
import java.util.Arrays;
import org.gephi.ranking.api.Transformer;
import org.openide.util.Exceptions;

/**
 * Color transformer. Uses a linear gradient to apply colors to objects.
 * 
 * @see Transformer
 * @author Mathieu Bastian
 */
public abstract class AbstractColorTransformer<Target> extends AbstractTransformer<Target> {

    protected LinearGradient linearGradient = new LinearGradient(new Color[]{Color.WHITE, Color.BLACK}, new float[]{0f, 1f});

    public AbstractColorTransformer() {
    }

    public AbstractColorTransformer(float lowerBound, float upperBound) {
        super(lowerBound, upperBound);
    }

    public AbstractColorTransformer(float lowerBound, float upperBound, Color[] colors, float[] positions) {
        super(lowerBound, upperBound);
        this.linearGradient = new LinearGradient(colors, positions);
    }

    public AbstractColorTransformer(Color[] colors, float[] positions) {
        this.linearGradient = new LinearGradient(colors, positions);
    }

    public LinearGradient getLinearGradient() {
        try {
            return (LinearGradient)linearGradient.clone();
        } catch (CloneNotSupportedException ex) {
            Exceptions.printStackTrace(ex);
        }
        return null;
    }

    public void setLinearGradient(LinearGradient linearGradient) {
        this.linearGradient = linearGradient;
    }

    public float[] getColorPositions() {
        return linearGradient.getPositions();
    }

    public Color[] getColors() {
        return linearGradient.getColors();
    }

    public void setColorPositions(float[] positions) {
        linearGradient.setPositions(positions);
    }

    public void setColors(Color[] colors) {
        linearGradient.setColors(colors);
    }

    public Color getColor(float normalizedValue) {
        return linearGradient.getValue(normalizedValue);
    }

    public static class LinearGradient implements Serializable, Cloneable {

        private Color[] colors;
        private float[] positions;

        public LinearGradient(Color colors[], float[] positions) {
            if (colors == null || positions == null) {
                throw new NullPointerException();
            }
            if (colors.length != positions.length) {
                throw new IllegalArgumentException();
            }
            this.colors = colors;
            this.positions = positions;
        }

        public Color getValue(float pos) {
            for (int a = 0; a < positions.length - 1; a++) {
                if (positions[a] == pos) {
                    return colors[a];
                }
                if (positions[a] < pos && pos < positions[a + 1]) {
                    float v = (pos - positions[a]) / (positions[a + 1] - positions[a]);
                    return tween(colors[a], colors[a + 1], v);
                }
            }
            if (pos <= positions[0]) {
                return colors[0];
            }
            if (pos >= positions[positions.length - 1]) {
                return colors[colors.length - 1];
            }
            return null;
        }

        private Color tween(Color c1, Color c2, float p) {
            return new Color(
                    (int) (c1.getRed() * (1 - p) + c2.getRed() * (p)),
                    (int) (c1.getGreen() * (1 - p) + c2.getGreen() * (p)),
                    (int) (c1.getBlue() * (1 - p) + c2.getBlue() * (p)),
                    (int) (c1.getAlpha() * (1 - p) + c2.getAlpha() * (p)));
        }

        public Color[] getColors() {
            return colors;
        }

        public float[] getPositions() {
            return positions;
        }

        public void setColors(Color[] colors) {
            this.colors = colors;
        }

        public void setPositions(float[] positions) {
            this.positions = positions;
        }

        @Override
        public boolean equals(Object obj) {
            if (obj == null) {
                return false;
            }
            if (getClass() != obj.getClass()) {
                return false;
            }
            final LinearGradient other = (LinearGradient) obj;
            if (!Arrays.deepEquals(this.colors, other.colors)) {
                return false;
            }
            if (!Arrays.equals(this.positions, other.positions)) {
                return false;
            }
            return true;
        }

        @Override
        public int hashCode() {
            int hash = 3;
            hash = 17 * hash + Arrays.deepHashCode(this.colors);
            hash = 17 * hash + Arrays.hashCode(this.positions);
            return hash;
        }

        @Override
        protected Object clone() throws CloneNotSupportedException {
            LinearGradient cl = new LinearGradient(colors, positions);
            return cl;
        }
    }
}