001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.imaging.color;
018
019/**
020 * Represents a color in the Hunter Lab color space.
021 *
022 * <p>
023 * Contains the constant values for black, white, red, green, and blue.
024 * </p>
025 *
026 * @see <a href="https://en.wikipedia.org/wiki/CIELAB_color_space#Hunter_Lab">https://en.wikipedia.org/wiki/CIELAB_color_space#Hunter_Lab</a>
027 * @since 1.0-alpha1
028 */
029public final class ColorHunterLab {
030
031    /**
032     * A constant for color black. Color components are:
033     *
034     * <pre>
035     *     L: 0
036     *     a: 0
037     *     b: 0
038     * </pre>
039     */
040    public static final ColorHunterLab BLACK = new ColorHunterLab(0, 0, 0);
041
042    /**
043     * A constant for color white. Color components are:
044     *
045     * <pre>
046     *     L: 100.000
047     *     a:  -5.336
048     *     b:   5.433
049     * </pre>
050     */
051    public static final ColorHunterLab WHITE = new ColorHunterLab(100, -5.336, 5.433);
052
053    /**
054     * A constant for color red. Color components are:
055     *
056     * <pre>
057     *     L: 46.109
058     *     a: 78.962
059     *     b: 29.794
060     * </pre>
061     */
062    public static final ColorHunterLab RED = new ColorHunterLab(46.109, 78.962, 29.794);
063
064    /**
065     * A constant for color green. Color components are:
066     *
067     * <pre>
068     *     L:  84.569
069     *     a: -72.518
070     *     b:  50.842
071     * </pre>
072     */
073    public static final ColorHunterLab GREEN = new ColorHunterLab(84.569, -72.518, 50.842);
074
075    /**
076     * A constant for color blue. Color components are:
077     *
078     * <pre>
079     *     L:   26.870
080     *     a:   72.885
081     *     b: -190.923
082     * </pre>
083     */
084    public static final ColorHunterLab BLUE = new ColorHunterLab(26.870, 72.885, -190.923);
085
086    public final double l;
087    public final double a;
088    public final double b;
089
090    public ColorHunterLab(final double l, final double a, final double b) {
091        this.l = l;
092        this.a = a;
093        this.b = b;
094    }
095
096    @Override
097    public boolean equals(final Object o) {
098        if (this == o) {
099            return true;
100        }
101        if (o == null || getClass() != o.getClass()) {
102            return false;
103        }
104
105        final ColorHunterLab that = (ColorHunterLab) o;
106        if (Double.compare(that.l, l) != 0) {
107            return false;
108        }
109        if (Double.compare(that.a, a) != 0) {
110            return false;
111        }
112        if (Double.compare(that.b, b) != 0) {
113            return false;
114        }
115
116        return true;
117    }
118
119    @Override
120    public int hashCode() {
121        int result;
122        long temp;
123        temp = Double.doubleToLongBits(l);
124        result = (int) (temp ^ temp >>> 32);
125        temp = Double.doubleToLongBits(a);
126        result = 31 * result + (int) (temp ^ temp >>> 32);
127        temp = Double.doubleToLongBits(b);
128        return 31 * result + (int) (temp ^ temp >>> 32);
129    }
130
131    @Override
132    public String toString() {
133        return "{L: " + l + ", a: " + a + ", b: " + b + "}";
134    }
135}