Minecraft map color matching

BasicEuclideanComparator.java

import java.awt.*;
import java.util.Comparator;

/**
 * The basic euclidean comparator is a simple comparator that compares two colors
 * based on their euclidean distance.
 *
 * @author Illusion
 */
public class BasicEuclideanComparator implements Comparator<Color> {

    @Override
    public int compare(Color color, Color t1) {
        int r1 = color.getRed();
        int g1 = color.getGreen();
        int b1 = color.getBlue();

        int r2 = t1.getRed();
        int g2 = t1.getGreen();
        int b2 = t1.getBlue();

        return (int) Math.sqrt(Math.pow(r1 - r2, 2) + Math.pow(g1 - g2, 2) + Math.pow(b1 - b2, 2));
    }
}

ColorMatcher.java

import java.awt.*;
import java.util.Comparator;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
 * The color matcher class is used to match a color to a Minecraft map color.
 * You can define a custom comparator to use for matching colors, which can be tuned to your liking.
 * The default comparator is the {@link BasicEuclideanComparator}.
 * Another option is the {@link WeightedEuclideanComparator}, which produces brighter yellows and oranges.
 * <p>
 * These colors are defined up to 1.18.2, and it is expected that you will update this class when a new Minecraft version with new map colors is released.
 *
 * @author Illusion
 */
public class ColorMatcher {

    private static final Color[] MAP_COLORS;

    private static final Comparator<Color> COMPARATOR = new BasicEuclideanComparator();
    private static final Map<Color, Integer> matchedColors = new ConcurrentHashMap<>();

    static {
        final Color[] baseMapColors = new Color[]
                {
                        new Color(0, 0, 0, 0), // transparent
                        new Color(127, 178, 56), // grass
                        new Color(247, 233, 163), // sand
                        new Color(199, 199, 199), // wool
                        new Color(255, 0, 0), // fire
                        new Color(160, 160, 255), // ice
                        new Color(167, 167, 167), // metal
                        new Color(0, 124, 0), // Plant
                        new Color(255, 255, 255), // Snow
                        new Color(164, 168, 184), // Clay
                        new Color(151, 109, 77), // Dirt
                        new Color(112, 112, 112), // Stone
                        new Color(64, 64, 255), // Water
                        new Color(143, 119, 72), // Wood
                        //new 1.7 colors (13w42a/13w42b)
                        new Color(255, 252, 245), // Quartz
                        new Color(216, 127, 51), // COLOR_ORANGE
                        new Color(178, 76, 216), // COLOR_MAGENTA
                        new Color(102, 153, 216), // COLOR_LIGHT_BLUE
                        new Color(229, 229, 51), // COLOR_YELLOW
                        new Color(127, 204, 25), // COLOR_LIGHT_GREEN
                        new Color(242, 127, 165), // COLOR_PINK
                        new Color(76, 76, 76), // COLOR_GREY
                        new Color(153, 153, 153), // COLOR_LIGHT_GREY
                        new Color(76, 127, 153), // COLOR_CYAN
                        new Color(127, 63, 178), // COLOR_PURPLE
                        new Color(51, 76, 178), // COLOR_BLUE
                        new Color(102, 76, 51), // COLOR_BROWN
                        new Color(102, 127, 51), // COLOR_GREEN
                        new Color(153, 51, 51), // COLOR_RED
                        new Color(25, 25, 25), // COLOR_BLACK
                        new Color(250, 238, 77), // GOLD
                        new Color(92, 219, 213), // Diamond
                        new Color(74, 128, 255), // lapis
                        new Color(0, 217, 58), // emerald
                        new Color(129, 86, 49), // podzol
                        new Color(112, 2, 0), // NETHER
                        //new 1.8 colors
                        new Color(209, 177, 161), // TERRACOTTA_WHITE
                        new Color(159, 82, 36), // TERRACOTTA_ORANGE
                        new Color(149, 87, 108), // terracotta magenta
                        new Color(112, 108, 138), // terracotta_light_blue
                        new Color(186, 133, 36), // terracotta_yellow
                        new Color(103, 117, 53), // terracotta_light_green
                        new Color(160, 77, 78), // terracotta_pink
                        new Color(57, 41, 35), // terracotta_grey
                        new Color(135, 107, 98), // terracotta_light_grey
                        new Color(87, 92, 92), // terracotta_cyan
                        new Color(122, 73, 88), // terracotta_purple
                        new Color(76, 62, 92), // terracotta_blue
                        new Color(76, 50, 35), // terracotta_brown
                        new Color(76, 50, 35), // terracotta_green
                        new Color(142, 60, 46), // terracotta_red
                        new Color(37, 22, 16), // terracotta_black
                        //1.16
                        new Color(189, 48, 49), // CRIMson_nylium
                        new Color(148, 63, 97), // crimson_stem
                        new Color(92, 25, 29), // crimson_hyphae
                        new Color(22, 126, 134), // warped_nylium
                        new Color(58, 142, 140), // warped_stem
                        new Color(86, 44, 62), // warped_hyphae
                        new Color(20, 180, 133), // warped_wart_block
                        // cliffs update (1.18 / 1.19)
                        new Color(100, 100, 100), // deepslate
                        new Color(216, 175, 147), // raw iron
                        new Color(127, 167, 150), // glow lichen
                };

        MAP_COLORS = new Color[baseMapColors.length * 4];

        for (int index = 0; index < baseMapColors.length; ++index) {
            Color baseColor = baseMapColors[index];

            MAP_COLORS[index * 4] = new Color(
                    (int) (baseColor.getRed() * 180.0 / 255.0 + 0.5),
                    (int) (baseColor.getGreen() * 180.0 / 255.0 + 0.5),
                    (int) (baseColor.getBlue() * 180.0 / 255.0 + 0.5),
                    baseColor.getAlpha()
            );

            MAP_COLORS[index * 4 + 1] = new Color(
                    (int) (baseColor.getRed() * 220.0 / 255.0 + 0.5),
                    (int) (baseColor.getGreen() * 220.0 / 255.0 + 0.5),
                    (int) (baseColor.getBlue() * 220.0 / 255.0 + 0.5),
                    baseColor.getAlpha()
            );

            MAP_COLORS[index * 4 + 2] = baseColor;

            MAP_COLORS[index * 4 + 3] = new Color(
                    (int) (baseColor.getRed() * 135.0 / 255.0 + 0.5),
                    (int) (baseColor.getGreen() * 135.0 / 255.0 + 0.5),
                    (int) (baseColor.getBlue() * 135.0 / 255.0 + 0.5),
                    baseColor.getAlpha()
            );
        }
    }

    /**
     * Returns the closest color index (in the map colors palette) for the given color.
     * Results are cached.
     *
     * @param color the color to match
     * @return the closest color index
     */
    public static byte getColor(Color color) {
        if (color.getAlpha() == 0) {
            return 0;
        }

        byte cached = matchedColors.getOrDefault(color, -1).byteValue();

        if (cached != -1) {
            return cached;
        }

        int best = 0;
        int bestDistance = Integer.MAX_VALUE;

        for (int i = 0; i < MAP_COLORS.length; ++i) {
            Color mappedColor = MAP_COLORS[i];

            if (mappedColor.getAlpha() == 0) {
                continue; // skip transparent colors
            }

            int distance = COMPARATOR.compare(color, mappedColor);
            if (distance < bestDistance) {
                bestDistance = distance;
                best = i;
            }
        }

        matchedColors.put(color, best);
        return (byte) best;
    }

    /**
     * Returns the color for the given index.
     *
     * @param original the original color
     * @return the closest color available in the map colors palette
     */
    public static Color getClosestColor(Color original) {
        if (original.getAlpha() == 0) {
            return new Color(0, 0, 0, 0);
        }

        int best = 0;
        int bestDistance = Integer.MAX_VALUE;

        for (int i = 0; i < MAP_COLORS.length; ++i) {
            Color mappedColor = MAP_COLORS[i];

            if (mappedColor.getAlpha() == 0) {
                continue; // skip transparent colors
            }

            int distance = COMPARATOR.compare(original, mappedColor);
            if (distance < bestDistance) {
                bestDistance = distance;
                best = i;
            }
        }

        return MAP_COLORS[best];
    }
}

WeightedEuclideanComparator.java

import java.awt.*;
import java.util.Comparator;

/**
 * The weighted euclidean comparator is a comparator that compares two colors
 * based on their euclidean distance, but with a weighted variance.
 *
 * @author Illusion
 */
public class WeightedEuclideanComparator implements Comparator<Color> {

    @Override
    public int compare(Color color, Color t1) {
        int r1 = color.getRed();
        int g1 = color.getGreen();
        int b1 = color.getBlue();

        int r2 = t1.getRed();
        int g2 = t1.getGreen();
        int b2 = t1.getBlue();

        int deltaR = r1 - r2;
        int deltaG = g1 - g2;
        int deltaB = b1 - b2;
        int redVariance = (int) (1 / 2f * (r1 + r2));

        if (redVariance < 128) {
            return (int) (Math.sqrt(
                    Math.pow(2 * deltaR, 2) + Math.pow(4 * deltaG, 2) + Math.pow(3 * deltaB, 2)));
        }

        return (int) (Math.sqrt(
                Math.pow(3 * deltaR, 2) + Math.pow(4 * deltaG, 2) + Math.pow(2 * deltaB, 2)));
    }
}