Support fancier packing of trimmed tilesets.

By default, it still does the same thing, but now you
can pass in a fancier packer.

Provided a SLIGHTLY fancier one that's still pretty dumb and
wasteful, but allows row wrapping instead of gluing everything
together into one super wide image; I've got some that otherwise
wind up SO insanely wide that it causes problems decoding them.

tools/src/main/java/com/threerings/media/tile/bundle/tools/TileSetBundler.java

@@ -31,6 +31,7 @@ import java.io.OutputStream;
 import java.awt.image.BufferedImage;
 import javax.imageio.ImageIO;
 
+import com.google.common.base.Supplier;
 import com.google.common.collect.Lists;
 
 import net.sf.json.JSONArray;
@@ -56,6 +57,7 @@ import com.threerings.media.tile.TrimmedObjectTileSet;
 import com.threerings.media.tile.bundle.BundleUtil;
 import com.threerings.media.tile.bundle.TileSetBundle;
 import com.threerings.media.tile.tools.xml.TileSetRuleSet;
+import com.threerings.media.tile.util.TileSetTrimmer;
 
 import static com.threerings.media.Log.log;
 
@@ -153,6 +155,15 @@ public class TileSetBundler
             return this;
         }
 
+        /**
+         * Sets the Packer to use when trimming.
+         */
+        public Writer usePacker (Supplier<TileSetTrimmer.Packer> packer)
+        {
+            this.packer = packer;
+            return trimImages(packer != null);
+        }
+
         /**
          * Sets whether or not we write out raw images.
          */
@@ -194,6 +205,7 @@ public class TileSetBundler
 
         boolean trim = true;
         boolean raw = true;
+        Supplier<TileSetTrimmer.Packer> packer;
         String imageBase;
         JSONConversion.Config json;
     }
@@ -429,7 +441,7 @@ public class TileSetBundler
                         // write the trimmed tileset image to the target file
                         TrimmedObjectTileSet tset =
                             TrimmedObjectTileSet.trimObjectTileSet((ObjectTileSet)set, dest,
-                                target.raw ? FastImageIO.FILE_SUFFIX : "png");
+                                target.raw ? FastImageIO.FILE_SUFFIX : "png", target.packer.get());
                         tset.setImagePath(imagePath);
                         // replace the original set with the trimmed
                         // tileset in the tileset bundle