Plex-FAWE/worldedit-core/src/main/java/com/boydti/fawe/util/RandomTextureUtil.java

package com.boydti.fawe.util;

import com.sk89q.worldedit.world.block.BlockType;
import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;

import java.io.FileNotFoundException;
import java.util.concurrent.ThreadLocalRandom;

public class RandomTextureUtil extends CachedTextureUtil {

    public RandomTextureUtil(TextureUtil parent) throws FileNotFoundException {
        super(parent);
    }

    private int index;
    private final int[] biomeMixBuffer = new int[3];
    private final Int2ObjectOpenHashMap<Integer> offsets = new Int2ObjectOpenHashMap<>();
    private final Int2ObjectOpenHashMap<int[]> biomeMixes = new Int2ObjectOpenHashMap<>();

    protected int addRandomColor(int c1, int c2) {
        int red1 = (c1 >> 16) & 0xFF;
        int green1 = (c1 >> 8) & 0xFF;
        int blue1 = (c1 >> 0) & 0xFF;
        byte red2 = (byte) (c2 >> 16);
        byte green2 = (byte) (c2 >> 8);
        byte blue2 = (byte) (c2 >> 0);
        int red = MathMan.clamp(red1 + random(red2), 0, 255);
        int green = MathMan.clamp(green1 + random(green2), 0, 255);
        int blue = MathMan.clamp(blue1 + random(blue2), 0, 255);
        return (red << 16) + (green << 8) + (blue << 0) + (255 << 24);
    }

    private int random(int i) {
        if (i < 0) {
            int i1 = -i;
            return -ThreadLocalRandom.current().nextInt(i1);
        } else {
            return ThreadLocalRandom.current().nextInt(i);
        }
    }

    @Override
    public boolean getIsBlockCloserThanBiome(char[] blockAndBiomeIdOutput, int color, int biomePriority) {
        BlockType block = getNearestBlock(color);
        int[] mix = biomeMixes.getOrDefault(color, null);
        if (mix == null) {
            int average = getBiomeMix(biomeMixBuffer, color);
            mix = new int[4];
            System.arraycopy(biomeMixBuffer, 0, mix, 0, 3);
            mix[3] = average;
            biomeMixes.put(color, mix);
        }
        if (++index > 2) index = 0;
        int biomeId = mix[index];
        int biomeAvColor = mix[3];
        int blockColor = getColor(block);
        blockAndBiomeIdOutput[0] = block.getDefaultState().getOrdinalChar();
        blockAndBiomeIdOutput[1] = (char) biomeId;
        if (colorDistance(biomeAvColor, color) - biomePriority > colorDistance(blockColor, color)) {
            return true;
        }
        return false;
    }


    @Override
    public BiomeColor getNearestBiome(int color) {
        int[] mix = biomeMixes.getOrDefault(color, null);
        if (mix == null) {
            int average = getBiomeMix(biomeMixBuffer, color);
            mix = new int[4];
            System.arraycopy(biomeMixBuffer, 0, mix, 0, 3);
            mix[3] = average;
            biomeMixes.put(color, mix);
        }
        if (++index > 2) index = 0;
        int biomeId = mix[index];
        return getBiome(biomeId);
    }

    @Override
    public BlockType getNearestBlock(int color) {
        int offsetColor = offsets.getOrDefault((Object)color, 0);
        if (offsetColor != 0) {
            offsetColor = addRandomColor(color, offsetColor);
        } else {
            offsetColor = color;
        }
        BlockType res = super.getNearestBlock(offsetColor);
        if (res == null) return null;
        int newColor = getColor(res);
        byte dr = (byte) (((color >> 16) & 0xFF) - ((newColor >> 16) & 0xFF));
        byte dg = (byte) (((color >> 8) & 0xFF) - ((newColor >> 8) & 0xFF));
        byte db = (byte) (((color >> 0) & 0xFF) - ((newColor >> 0) & 0xFF));
        offsets.put(color, (Integer) ((dr << 16) + (dg << 8) + (db << 0)));
        return res;
    }
}