noise gen

src/main/java/carpet/script/utils/SimplexNoiseSampler.java

@@ -0,0 +1,67 @@
+package carpet.script.utils;
+
+import java.util.Random;
+
+public class SimplexNoiseSampler extends PerlinNoiseSampler {
+    private static final double sqrt3 = Math.sqrt(3.0D);
+    private static final double SKEW_FACTOR_2D;
+    private static final double UNSKEW_FACTOR_2D;
+
+    public static SimplexNoiseSampler instance = new SimplexNoiseSampler(new Random(0));
+
+    public SimplexNoiseSampler(Random random) {
+        super(random);
+    }
+
+    private double grad(int hash, double x, double y, double z, double d) {
+        double e = d - x * x - y * y - z * z;
+        double g;
+        if (e < 0.0D) {
+            g = 0.0D;
+        } else {
+            e *= e;
+            g = e * e * PerlinNoiseSampler.dot3d(PerlinNoiseSampler.gradients3d[hash], x, y, z);
+        }
+
+        return g;
+    }
+
+    public double sample(double x, double y) {
+        double d = (x + y) * SKEW_FACTOR_2D;
+        int i = PerlinNoiseSampler.floor(x + d);
+        int j = PerlinNoiseSampler.floor(y + d);
+        double e = (double)(i + j) * UNSKEW_FACTOR_2D;
+        double f = (double)i - e;
+        double g = (double)j - e;
+        double h = x - f;
+        double k = y - g;
+        byte n;
+        byte o;
+        if (h > k) {
+            n = 1;
+            o = 0;
+        } else {
+            n = 0;
+            o = 1;
+        }
+
+        double p = h - (double)n + UNSKEW_FACTOR_2D;
+        double q = k - (double)o + UNSKEW_FACTOR_2D;
+        double r = h - 1.0D + 2.0D * UNSKEW_FACTOR_2D;
+        double s = k - 1.0D + 2.0D * UNSKEW_FACTOR_2D;
+        int t = i & 255;
+        int u = j & 255;
+        int v = this.getGradient(t + this.getGradient(u)) % 12;
+        int w = this.getGradient(t + n + this.getGradient(u + o)) % 12;
+        int z = this.getGradient(t + 1 + this.getGradient(u + 1)) % 12;
+        double aa = this.grad(v, h, k, 0.0D, 0.5D);
+        double ab = this.grad(w, p, q, 0.0D, 0.5D);
+        double ac = this.grad(z, r, s, 0.0D, 0.5D);
+        return 70.0D * (aa + ab + ac);
+    }
+
+    static {
+        SKEW_FACTOR_2D = 0.5D * (sqrt3 - 1.0D);
+        UNSKEW_FACTOR_2D = (3.0D - sqrt3) / 6.0D;
+    }
+}