Implement more noise patterns

worldedit-core/src/main/java/com/boydti/fawe/object/random/NoiseRandom.java

@@ -0,0 +1,34 @@
+package com.boydti.fawe.object.random;
+
+import com.sk89q.worldedit.math.Vector3;
+import com.sk89q.worldedit.math.noise.NoiseGenerator;
+
+public class NoiseRandom implements SimpleRandom {
+
+    private final NoiseGenerator generator;
+    private final double scale;
+
+    /**
+     * Create a new NoiseRandom instance using a specific {@link NoiseGenerator} and a scale.
+     *
+     * @param generator The generator to use for the noise
+     * @param scale     The scale of the noise
+     */
+    public NoiseRandom(NoiseGenerator generator, double scale) {
+        this.generator = generator;
+        this.scale = scale;
+    }
+
+    @Override
+    public double nextDouble(int x, int y, int z) {
+        return cap(this.generator.noise(Vector3.at(x, y, z).multiply(this.scale)));
+    }
+
+    // workaround for noise generators returning [0, 1]
+    private double cap(double d) {
+        if (d >= 1.0) {
+            return 0x1.fffffffffffffp-1; // very close to 1 but less
+        }
+        return d;
+    }
+}

worldedit-core/src/main/java/com/boydti/fawe/object/random/SimpleRandom.java

@@ -2,10 +2,29 @@ package com.boydti.fawe.object.random;
 
 public interface SimpleRandom {
 
+    /**
+     * Generate a random double from three integer components.
+     * The generated value is between 0 (inclusive) and 1 (exclusive).
+     *
+     * @param x the first component
+     * @param y the second component
+     * @param z the third component
+     * @return a double between 0 (inclusive) and 1 (exclusive)
+     */
     double nextDouble(int x, int y, int z);
 
-    default int nextInt(int x, int y, int z, int len) {
+    /**
+     * Generate a random integer from three integer components.
+     * The generated value is between 0 (inclusive) and 1 (exclusive)
+     *
+     * @param x the first component
+     * @param y the second component
+     * @param z the third component
+     * @param bound the upper bound (exclusive)
+     * @return a random integer between 0 (inclusive) and {@code bound} (exclusive)
+     */
+    default int nextInt(int x, int y, int z, int bound) {
         double val = nextDouble(x, y, z);
-        return (int) (val * len);
+        return (int) (val * bound);
     }
 }

worldedit-core/src/main/java/com/boydti/fawe/object/random/SimplexRandom.java

@@ -1,14 +0,0 @@
-package com.boydti.fawe.object.random;
-
-public class SimplexRandom implements SimpleRandom {
-    private final double scale;
-
-    public SimplexRandom(double scale) {
-        this.scale = scale;
-    }
-
-    @Override
-    public double nextDouble(int x, int y, int z) {
-        return (SimplexNoise.noise(x * scale, y * scale, z * scale) + 1) * 0.5;
-    }
-}