protected void defineWorld(int worldType) {
    world = new HashMap<Position,Tile>();
    String[] layout;
    if ( worldType == 1 ) {
      layout = new String[] {
          "...ooMooooo.....",
          "..ohhoooofffoo..",
          ".oooooMooo...oo.",
          ".ooMMMoooo..oooo",
          "...ofooohhoooo..",
          ".ofoofooooohhoo.",
          "...ooo..........",
          ".ooooo.ooohooM..",
          ".ooooo.oohooof..",
          "offfoooo.offoooo",
          "oooooooo...ooooo",
          ".ooMMMoooo......",
          "..ooooooffoooo..",
          "....ooooooooo...",
          "..ooohhoo.......",
          ".....ooooooooo..",
         };
    } else {
      layout = new String[] {
          "...ooo..........",
          ".ooooo.ooohooM..",
          ".ooooo.oohooof..",
          "offfoooo.offoooo",
          "oooooooo...ooooo",
          ".ooMMMoooo......",
          ".....ooooooooo..",
          "...ooMooooo.....",
          "..ohhoooofffoo..",
          "...ofooohhoooo..",
          ".oooooMooo...oo.",
          ".ooMMMoooo..oooo",
          ".ofoofooooohhoo.",
          "..ooooooffoooo..",
          "....ooooooooo...",
          "..ooohhoo.......",
         };      
    }
    String line;
    for ( int r = 0; r < GameConstants.WORLDSIZE; r++ ) {
      line = layout[r];
      for ( int c = 0; c < GameConstants.WORLDSIZE; c++ ) {
        char tileChar = line.charAt(c);
        String type = "error";
        if ( tileChar == '.' ) { type = GameConstants.OCEANS; }
        if ( tileChar == 'o' ) { type = GameConstants.PLAINS; }
        if ( tileChar == 'M' ) { type = GameConstants.MOUNTAINS; }
        if ( tileChar == 'f' ) { type = GameConstants.FOREST; }
        if ( tileChar == 'h' ) { type = GameConstants.HILLS; }
        Position p = new Position(r,c);
        world.put( p, new StubTile(p, type));
      }
    }
  }