Sounds similar to https://en.wikipedia.org/wiki/Contraction_hierarchies https://en.wikipedia.org/wiki/Contraction_hierarchies There was a paper by Microsoft Re

Sounds similar to https://en.wikipedia.org/wiki/Contraction_hierarchies https://en.wikipedia.org/wiki/Contraction_hierarchies There was a paper by Microsoft Research where they find shortest path from one point to another in time equivalent to 5 memory reads + they sped up significantly the precomputation times and lowered memory requirements.