Java Color Interpolate interpolateColor(final Color minColor, final Color maxColor, final int currentClass, final int numOfClasses)

Description

returns the interpolated color of a color map defined by start and end color.

License

Open Source License

Parameter

Parameter	Description
currentClass	current class
numOfClasses	number of all classes in which the colormap is divided.

Declaration

public static Color interpolateColor(final Color minColor,
        final Color maxColor, final int currentClass,
        final int numOfClasses) 

Method Source Code

//package com.java2s;
/*----------------    FILE HEADER KALYPSO ------------------------------------------
 *
 *  This file is part of kalypso.//ww w  .j a va 2 s.com
 *  Copyright (C) 2004 by:
 *
 *  Technical University Hamburg-Harburg (TUHH)
 *  Institute of River and coastal engineering
 *  Denickestra?e 22
 *  21073 Hamburg, Germany
 *  http://www.tuhh.de/wb
 *
 *  and
 *
 *  Bjoernsen Consulting Engineers (BCE)
 *  Maria Trost 3
 *  56070 Koblenz, Germany
 *  http://www.bjoernsen.de
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  Contact:
 *
 *  E-Mail:
 *  belger@bjoernsen.de
 *  schlienger@bjoernsen.de
 *  v.doemming@tuhh.de
 *
 *  ---------------------------------------------------------------------------*/

import java.awt.Color;

public class Main {
    /**
     * returns the interpolated color of a color map defined by start and end color.
     * 
     * @param currentClass
     *          current class
     * @param numOfClasses
     *          number of all classes in which the colormap is divided.
     */
    public static Color interpolateColor(final Color minColor,
            final Color maxColor, final int currentClass,
            final int numOfClasses) {
        // interpolate color
        final float[] minhsb = Color.RGBtoHSB(minColor.getRed(),
                minColor.getGreen(), minColor.getBlue(), null);
        final float[] maxhsb = Color.RGBtoHSB(maxColor.getRed(),
                maxColor.getGreen(), maxColor.getBlue(), null);

        final float minHue = minhsb[0];
        final float maxHue = maxhsb[0];

        final float minSat = minhsb[1];
        final float maxSat = maxhsb[1];

        final float minBri = minhsb[2];
        final float maxBri = maxhsb[2];

        final double Hue = minHue
                + (currentClass * (maxHue - minHue) / (numOfClasses - 1));
        final double Sat = minSat
                + (currentClass * (maxSat - minSat) / (numOfClasses - 1));
        final double Bri = minBri
                + (currentClass * (maxBri - minBri) / (numOfClasses - 1));

        final Color hsbColor = Color.getHSBColor((float) Hue, (float) Sat,
                (float) Bri);
        final Color rgbColor = new Color(hsbColor.getRed(),
                hsbColor.getGreen(), hsbColor.getBlue());

        return rgbColor;
    }
}

Related

1. interpolate(final Color aBaseColor, final Color aSecondaryColor, final float aDelta)
2. interpolate(final Color from, final Color to, final double t)
3. interpolate(java.awt.Color a, java.awt.Color b, float portion)
4. interpolate2Color(final Color first, final Color second, float fraction)
5. interpolateColor(Color color0, Color color1, double mixer, boolean useHue)
6. interpolateRGB(Color start, Color end, float p)