code: private void resolve(Collection<Tile> resolved, Collection<Tile> toResolve, Tile tile)
      {
          updateTile(resolved, toResolve, tile, -1, 0);
          updateTile(resolved, toResolve, tile, 1, 0);
          updateTile(resolved, toResolve, tile, 0, 1);
          updateTile(resolved, toResolve, tile, 0, -1);
  
          updateTile(resolved, toResolve, tile, -1, 1);
          updateTile(resolved, toResolve, tile, 1, 1);
          updateTile(resolved, toResolve, tile, -1, -1);
          updateTile(resolved, toResolve, tile, 1, -1);
      }
docs: Resolve current tile and add to resolve list extra tiles.
  
  @param resolved The resolved tiles.
  @param toResolve The next tiles to resolve.
  @param tile The tile to resolve.