001/*
002 *                  BioJava development code
003 *
004 * This code may be freely distributed and modified under the
005 * terms of the GNU Lesser General Public Licence.  This should
006 * be distributed with the code.  If you do not have a copy,
007 * see:
008 *
009 *      http://www.gnu.org/copyleft/lesser.html
010 *
011 * Copyright for this code is held jointly by the individual
012 * authors.  These should be listed in @author doc comments.
013 *
014 * For more information on the BioJava project and its aims,
015 * or to join the biojava-l mailing list, visit the home page
016 * at:
017 *
018 *      http://www.biojava.org/
019 *
020 * Created on Aug 3, 2007
021 */
022package org.biojava.nbio.structure.gui.util.color;
023
024import java.awt.*;
025
026/**
027 * Maps colors by performing a transform of the input data and then passing
028 * the transformed value to a ContinuousColorMapper for rendering.
029 *
030 * For instance, to map [10^0, 10^10] to a rainbow gradient, use
031 *
032 * new LogColorMapper(GradientMapper.getGradientMapper(GradientMapper.RAINBOW_GRADIENT, 0, 10))
033 *
034 * @author Spencer Bliven
035 *
036 */
037public abstract class ContinuousColorMapperTransform implements ContinuousColorMapper {
038
039        protected ContinuousColorMapper mapper;
040
041        /**
042         * Creates a transform.
043         * @param submapper A color mapper which acts on the transformed input value.
044         */
045        public ContinuousColorMapperTransform(ContinuousColorMapper submapper) {
046                this.mapper = submapper;
047        }
048
049        /**
050         * Return the color corresponding to submapper.getColor(transform(value)).
051         *
052         * @param value Value to be mapped
053         * @return color corresponding to transform(value)
054         * @see org.biojava.nbio.structure.gui.util.color.ContinuousColorMapper#getColor(double)
055         */
056        @Override
057        public Color getColor(double value) {
058                return mapper.getColor(transform(value));
059        }
060
061        /**
062         * An arbitrary transform over reals
063         * @param the input value
064         * @return the transformed value
065         */
066        public abstract double transform(double value);
067}