Added simple smoothing brush.

plugin.yml

@@ -14,6 +14,9 @@ commands:
         description: Choose the clipboard brush
         usage: /<command> [-a] 
         aliases: ['copy']
+    smooth:
+        description: Choose the terrain softener brush
+        usage: /<command> [size] [iterations]
     chunkinfo:
         description: Get information about the chunk that you are inside
         usage: /<command> 
@@ -107,6 +110,9 @@ commands:
     up:
         description: Go upwards some distance
         usage: /<command> <block>
+    /smooth:
+        description: Smooth the elevation in the selection
+        usage: /<command> [iterations]
     /overlay:
         description: Set a block on top of blocks in the region
         usage: /<command> <block>
@@ -117,9 +123,6 @@ commands:
         description: Build the walls, ceiling, and roof of a selection
         usage: /<command> <block>
         aliases: ['/outline']
-    /smooth:
-        description: Smooth the elevation in the selection
-        usage: /<command> [iterations]
     /replace:
         description: Replace all blocks in the selection with another
         usage: /<command> [from-block] <to-block>

src/com/sk89q/worldedit/commands/BrushCommands.java

@@ -36,6 +36,7 @@ import com.sk89q.worldedit.tools.brushes.ClipboardBrush;
 import com.sk89q.worldedit.tools.brushes.CylinderBrush;
 import com.sk89q.worldedit.tools.brushes.HollowCylinderBrush;
 import com.sk89q.worldedit.tools.brushes.HollowSphereBrush;
+import com.sk89q.worldedit.tools.brushes.SmoothBrush;
 import com.sk89q.worldedit.tools.brushes.SphereBrush;
 
 /**
@@ -162,4 +163,35 @@ public class BrushCommands {
         
         player.print("Clipboard brush shape equipped.");
     }
+
+    @Command(
+        aliases = {"smooth"},
+        usage = "[size] [iterations]",
+        desc = "Choose the terrain softener brush",
+        min = 0,
+        max = 2
+    )
+    @CommandPermissions({"worldedit.brush.smooth"})
+    public static void smoothBrush(CommandContext args, WorldEdit we,
+            LocalSession session, LocalPlayer player, EditSession editSession)
+            throws WorldEditException {
+        
+        LocalConfiguration config = we.getConfiguration();
+
+        int radius = args.argsLength() > 0 ? args.getInteger(0) : 2;
+        if (radius > config.maxBrushRadius) {
+            player.printError("Maximum allowed brush radius: "
+                    + config.maxBrushRadius);
+            return;
+        }
+
+        int iterations = args.argsLength() > 1 ? args.getInteger(1) : 4;
+
+        BrushTool tool = session.getBrushTool(player.getItemInHand());
+        tool.setSize(radius);
+        tool.setBrush(new SmoothBrush(iterations));
+
+        player.print(String.format("Smooth brush equipped (%d x %dx).",
+                radius, iterations));
+    }
 }

src/com/sk89q/worldedit/tools/brushes/SmoothBrush.java

@@ -0,0 +1,49 @@
+// $Id$
+/*
+ * WorldEdit
+ * Copyright (C) 2010, 2011 sk89q <http://www.sk89q.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package com.sk89q.worldedit.tools.brushes;
+
+import com.sk89q.worldedit.EditSession;
+import com.sk89q.worldedit.HeightMap;
+import com.sk89q.worldedit.MaxChangedBlocksException;
+import com.sk89q.worldedit.Vector;
+import com.sk89q.worldedit.filtering.GaussianKernel;
+import com.sk89q.worldedit.filtering.HeightMapFilter;
+import com.sk89q.worldedit.patterns.Pattern;
+import com.sk89q.worldedit.regions.CuboidRegion;
+import com.sk89q.worldedit.regions.Region;
+
+public class SmoothBrush implements Brush {
+    private int iterations;
+    
+    public SmoothBrush(int iterations) {
+        this.iterations = iterations;
+    }
+    
+    public void build(EditSession editSession, Vector pos, Pattern mat, int size)
+            throws MaxChangedBlocksException {
+        int rad = size;
+        Vector min = pos.subtract(rad, rad, rad);
+        Vector max = pos.add(rad, rad + 10, rad);
+        Region region = new CuboidRegion(min, max);
+        HeightMap heightMap = new HeightMap(editSession, region);
+        HeightMapFilter filter = new HeightMapFilter(new GaussianKernel(5, 1.0));
+        heightMap.applyFilter(filter, iterations);
+    }
+}