1 package org.opentrafficsim.draw;
2
3 import java.awt.Color;
4
5 /**
6 * List of colors to use for various legends.
7 * <p>
8 * Copyright (c) 2023-2024 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
9 * BSD-style license. See <a href="https://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
10 * </p>
11 * @author <a href="https://github.com/peter-knoppers">Peter Knoppers</a>
12 * @author <a href="https://github.com/wjschakel">Wouter Schakel</a>
13 */
14 public final class Colors
15 {
16
17 /** 3-color scale from green to red. */
18 public static final Color[] GREEN_RED = new Color[] {Color.GREEN, Color.YELLOW, Color.RED};
19
20 /** 5-color scale from green to red with dark edges. */
21 public static final Color[] GREEN_RED_DARK =
22 new Color[] {Color.GREEN.darker(), Color.GREEN, Color.YELLOW, Color.RED, Color.RED.darker()};
23
24 /** 6-color scale from magenta, through red-green, to blue. */
25 public static final Color[] ULTRA =
26 new Color[] {Color.MAGENTA, Color.RED, Color.ORANGE, Color.YELLOW, Color.GREEN, Color.BLUE};
27
28 /** 10-color scale for enumeration. */
29 public static final Color[] ENUMERATE = new Color[] {Color.BLACK, new Color(0xa5, 0x2a, 0x2a), Color.RED, Color.ORANGE,
30 Color.YELLOW, Color.GREEN, Color.BLUE, Color.MAGENTA, Color.GRAY, Color.WHITE};
31
32 /** Names of the enumerated colors. */
33 public static final String[] ENUMERATE_NAMES =
34 new String[] {"black", "brown", "red", "orange", "yellow", "green", "blue", "magenta", "gray", "white"};
35
36 /**
37 * Constructor.
38 */
39 private Colors()
40 {
41 //
42 }
43
44 /**
45 * Reverses the color array.
46 * @param colors array of colors
47 * @return reversed color array
48 */
49 public static Color[] reverse(final Color[] colors)
50 {
51 Color[] out = new Color[colors.length];
52 for (int i = 0; i < colors.length; i++)
53 {
54 out[colors.length - i - 1] = colors[i];
55 }
56 return out;
57 }
58
59 /**
60 * Creates an array of {@code n} colors with varying hue.
61 * @param n number of colors.
62 * @return array of {@code n} colors with varying hue
63 */
64 public static Color[] hue(final int n)
65 {
66 Color[] out = new Color[n];
67 for (int i = 0; i < n; i++)
68 {
69 out[i] = new Color(Color.HSBtoRGB(((float) i) / n, 1.0f, 1.0f));
70 }
71 return out;
72 }
73
74 /**
75 * Returns a color for the index. Modulo is applied for indices outside of the normal range.
76 * @param index index.
77 * @return color for index.
78 */
79 public static Color getEnumerated(final int index)
80 {
81 return ENUMERATE[mod(index)];
82 }
83
84 /**
85 * Returns the name of a color for the index. Modulo is applied for indices outside of the normal range.
86 * @param index index.
87 * @return name of color for index.
88 */
89 public static String nameEnumerated(final int index)
90 {
91 return ENUMERATE_NAMES[mod(index)];
92 }
93
94 /**
95 * Returns the modulo of the index given the number of colors we have.
96 * @param index index.
97 * @return index in range of colors.
98 */
99 private static int mod(final int index)
100 {
101 return Math.abs(index % ENUMERATE.length);
102 }
103
104 /**
105 * Returns a color from an array, where the used index is determined based on the id. If the last character of the id is a
106 * digit, that value is used. Otherwise it is the absolute hash code of the id. The modulo of either of these values given
107 * the number of colors is the index in the array of the color returned.
108 * @param id object id
109 * @param colors colors to select from
110 * @return color
111 */
112 public static Color getIdColor(final String id, final Color[] colors)
113 {
114 return colors[Character.isDigit(id.charAt(id.length() - 1)) ? id.charAt(id.length() - 1) - '0'
115 : Math.abs(id.hashCode()) % colors.length];
116 }
117
118 }