Uh, base 4 is exactly what I meant. I guess I wasn't very clear that I mean positions are encoded as bitstrings, with one pair of bits for each level (and tripl

Uh, base 4 is exactly what I meant. I guess I wasn't very clear that I mean positions are encoded as bitstrings, with one pair of bits for each level (and triples of bits for octrees). Is that clear enough for you?