SimplexNoise.java

package micdoodle8.mods.galacticraft.core.perlin;

import java.util.Random;

public class SimplexNoise
{
    int[] perm = new int[512];

    public int[][] grad2d = new int[][] { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 1, 0 } };

    public SimplexNoise(long seed)
    {
        final Random rand = new Random(seed);
        for (int i = 0; i < 256; i++)
        {
            this.perm[i] = i; // Fill up the random array with numbers 0-256
        }

        for (int i = 0; i < 256; i++) // Shuffle those numbers for the random
        // effect
        {
            final int j = rand.nextInt(256);
            this.perm[i] = this.perm[i] ^ this.perm[j];
            this.perm[j] = this.perm[i] ^ this.perm[j];
            this.perm[i] = this.perm[i] ^ this.perm[j];
        }

        System.arraycopy(this.perm, 0, this.perm, 256, 256);
    }

}