Added getTileSetId() and getTileIndex().

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@2257 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/tile/TileUtil.java

@@ -1,5 +1,5 @@
 //
-// $Id: TileUtil.java,v 1.4 2003/01/13 22:49:46 mdb Exp $
+// $Id: TileUtil.java,v 1.5 2003/02/12 05:32:35 mdb Exp $
 
 package com.threerings.media.tile;
 
@@ -9,13 +9,27 @@ package com.threerings.media.tile;
 public class TileUtil
 {
     /**
-     * Generates a fully-qualified tileid given the supplied tileset id
+     * Generates a fully-qualified tile id given the supplied tileset id
-     * and tile index. This fully-qualified id can be used to fetch the
+     * and tile index.
-     * tile from the tileset repository which knows about the supplied
-     * tileset id.
      */
     public static int getFQTileId (int tileSetId, int tileIndex)
     {
         return (tileSetId << 16) | tileIndex;
     }
+
+    /**
+     * Extracts the tile set id from the supplied fully qualified tile id.
+     */
+    public static int getTileSetId (int fqTileId)
+    {
+        return (fqTileId >> 16);
+    }
+
+    /**
+     * Extracts the tile index from the supplied fully qualified tile id.
+     */
+    public static int getTileIndex (int fqTileId)
+    {
+        return (fqTileId & 0xFFFF);
+    }
 }