Hiyas

Once again, I turn to the experts here for help with a simple prob...

Basically, I have a tile map. I need every tile to have 3 states - lit (explored), dark (unexplored) and dim (in sight but unexplored).

The hero steps on a tile, and that tile becomes "lit". The 9 tiles around hero become "dim".

I can't see any way to do this without changing the tile array and redrawing the whole map every time the hero moves. Am I missing something easier?

Thanks,

RM.