[GraphHopper] question on contraction

[Peter K]

>
> When the lazy updates are activated,
> * do we still need to update the neighbour points of a node we just
> contracted?

Lazy update is exactly for that purpose: updating the priorities of the
neighbour nodes of a contracted node

> * is it still needed to perform periodic updates of all the priorities?

we only do periodic updates for not yet contracted nodes

Keep in mind: all the ordering and preparation procedure is entirely
heuristic nature. But still it leads to an algorithm with correct
behaviour, no heuristics. The only difference e.g. if we don't do lazy
or periodic updates etc is the quality of how fast is the query, how
fast is the preparation itself and how many shortcuts were produced.

Peter.