It is not a lookup table - think more of some additional shortcuts you introduce for a certain mode. This way you get lots of speed but loose flexibility. In Gr

It is not a lookup table - think more of some additional shortcuts you introduce for a certain mode. This way you get lots of speed but loose flexibility. In GraphHopper you can enable and disable it, the code is here https://github.com/graphhopper/graphhopper/blob/master/core/src/main/java/com/graphhopper/routing/ch/PrepareContractionHierarchies.java https://github.com/graphhopper/graphhopper/blob/master/core/...