Add blob brush

- simplex distortions with a configurable frequency/amplitude

core/src/main/java/com/boydti/fawe/object/brush/BlobBrush.java

@@ -0,0 +1,51 @@
+package com.boydti.fawe.object.brush;
+
+import com.boydti.fawe.object.random.SimplexNoise;
+import com.sk89q.worldedit.EditSession;
+import com.sk89q.worldedit.MaxChangedBlocksException;
+import com.sk89q.worldedit.Vector;
+import com.sk89q.worldedit.command.tool.brush.Brush;
+import com.sk89q.worldedit.function.pattern.Pattern;
+import java.util.concurrent.ThreadLocalRandom;
+
+public class BlobBrush implements Brush {
+    private final double amplitude;
+    private final double frequency;
+
+    public BlobBrush(double frequency, double amplitude) {
+        this.frequency = frequency;
+        this.amplitude = amplitude;
+    }
+
+    @Override
+    public void build(EditSession editSession, Vector position, Pattern pattern, double size) throws MaxChangedBlocksException {
+        double seedX = ThreadLocalRandom.current().nextDouble();
+        double seedY = ThreadLocalRandom.current().nextDouble();
+        double seedZ = ThreadLocalRandom.current().nextDouble();
+
+        int px = position.getBlockX();
+        int py = position.getBlockY();
+        int pz = position.getBlockZ();
+
+        double distort = this.frequency / size;
+
+        int radiusSqr = (int) (size * size);
+        int sizeInt = (int) size * 2;
+        for (int x = -sizeInt; x <= sizeInt; x++) {
+            double nx = seedX + x * distort;
+            int d1 = x * x;
+            for (int y = -sizeInt; y <= sizeInt; y++) {
+                int d2 = d1 + y * y;
+                double ny = seedY + y * distort;
+                for (int z = -sizeInt; z <= sizeInt; z++) {
+                    double nz = seedZ + z * distort;
+                    double distance = d2 + z * z;
+                    double noise = this.amplitude * SimplexNoise.noise(nx, ny, nz);
+                    if (distance + distance * noise < radiusSqr) {
+                        editSession.setBlock(px + x, py + y, pz + z, pattern);
+                    }
+                }
+            }
+        }
+    }
+}

core/src/main/java/com/sk89q/worldedit/command/BrushCommands.java

@@ -26,6 +26,7 @@ import com.boydti.fawe.config.Settings;
 import com.boydti.fawe.object.FaweLimit;
 import com.boydti.fawe.object.FawePlayer;
 import com.boydti.fawe.object.brush.BlendBall;
+import com.boydti.fawe.object.brush.BlobBrush;
 import com.boydti.fawe.object.brush.BrushSettings;
 import com.boydti.fawe.object.brush.CatenaryBrush;
 import com.boydti.fawe.object.brush.CircleBrush;
@@ -286,6 +287,24 @@ public class BrushCommands extends MethodCommands {
                 .setFill(fill);
     }
 
+    @Command(
+            aliases = {"blob", "rock"},
+            usage = "<pattern> [radius=10] [frequency=30] [amplitude=50]",
+            flags = "h",
+            desc = "Creates a distorted sphere",
+            min = 1,
+            max = 4
+    )
+    @CommandPermissions("worldedit.brush.blob")
+    public BrushSettings blobBrush(Player player, EditSession editSession, LocalSession session, Pattern fill, @Optional("10") double radius, @Optional("30") double frequency, @Optional("50") double amplitude, CommandContext context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        Brush brush = new BlobBrush(frequency / 100, amplitude / 100);
+        return get(context)
+                .setBrush(brush)
+                .setSize(radius)
+                .setFill(fill);
+    }
+
     @Command(
             aliases = {"sphere", "s"},
             usage = "<pattern> [radius=2]",