It reminds me of Bill Gosper’s old code for Conway’s game of life from back in the 1980s. It used spatial and temporal hashing so it took several minute to do the first 1000 generations of the F pentonimo but just another second for the next 2^31 generations.
Hashing, sometimes using K-D trees, was common in image processing in the early 80s and into the 90s. There just wasn’t enough processing power, but if you created your tables cleverly you could get pretty good results a lot faster. (Professor Pentland at MIT got our group on the right track with this, way back when.) I suppose you never really have enough processing power.
