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 CIELCH color space.
021 *
022 * <p>
023 * Contains the constant values for black, white, red, green, and blue.
024 * </p>
025 *
026 * @see <a href=
027 *      "https://en.wikipedia.org/wiki/CIELUV#Cylindrical_representation_(CIELCH)">https://en.wikipedia.org/wiki/CIELUV#Cylindrical_representation_(CIELCH)</a>
028 * @since 1.0-alpha1
029 */
030public final class ColorCieLch {
031
032    /**
033     * A constant for color black. Color components are:
034     *
035     * <pre>
036     *     L*: 0
037     *     C*: 0
038     *     h: 0
039     * </pre>
040     */
041    public static final ColorCieLch BLACK = new ColorCieLch(0, 0, 0);
042
043    /**
044     * A constant for color white. Color components are:
045     *
046     * <pre>
047     *     L*: 100
048     *     C*:   0
049     *     h: 297
050     * </pre>
051     */
052    public static final ColorCieLch WHITE = new ColorCieLch(100, 0, 297);
053
054    /**
055     * A constant for color red. Color components are:
056     *
057     * <pre>
058     *     L*: 53
059     *     C*: 80
060     *     h: 67
061     * </pre>
062     */
063    public static final ColorCieLch RED = new ColorCieLch(53, 80, 67);
064
065    /**
066     * A constant for color green. Color components are:
067     *
068     * <pre>
069     *     L*:  88
070     *     C*: -86
071     *     h:  83
072     * </pre>
073     */
074    public static final ColorCieLch GREEN = new ColorCieLch(88, -86, 83);
075
076    /**
077     * A constant for color blue. Color components are:
078     *
079     * <pre>
080     *     L*:   32
081     *     C*:   79
082     *     h: -108
083     * </pre>
084     */
085    public static final ColorCieLch BLUE = new ColorCieLch(32, 79, -108);
086
087    /** L* lightness. */
088    public final double l;
089
090    /** C* chroma. */
091    public final double c;
092
093    /** Hue. */
094    public final double h;
095
096    /**
097     * Constructs a new instance.
098     *
099     * @param l L* lightness.
100     * @param c chroma.
101     * @param h hue.
102     */
103    public ColorCieLch(final double l, final double c, final double h) {
104        this.l = l;
105        this.c = c;
106        this.h = h;
107    }
108
109    @Override
110    public boolean equals(final Object o) {
111        if (this == o) {
112            return true;
113        }
114        if (o == null || getClass() != o.getClass()) {
115            return false;
116        }
117
118        final ColorCieLch that = (ColorCieLch) o;
119        if (Double.compare(that.c, c) != 0) {
120            return false;
121        }
122        if (Double.compare(that.h, h) != 0) {
123            return false;
124        }
125        if (Double.compare(that.l, l) != 0) {
126            return false;
127        }
128
129        return true;
130    }
131
132    @Override
133    public int hashCode() {
134        int result;
135        long temp;
136        temp = Double.doubleToLongBits(l);
137        result = (int) (temp ^ temp >>> 32);
138        temp = Double.doubleToLongBits(c);
139        result = 31 * result + (int) (temp ^ temp >>> 32);
140        temp = Double.doubleToLongBits(h);
141        return 31 * result + (int) (temp ^ temp >>> 32);
142    }
143
144    @Override
145    public String toString() {
146        return "{L: " + l + ", C: " + c + ", h: " + h + "}";
147    }
148}