How to avoid alpine regions and pyrenees?

[Bernd Welter]

Hi there,

I've been asked whether / how we can approach the requirements below in the Routing API:

Routings go through Pyrenees mountains in North Spain/South France, where no trucking companies go through. Companies go through either via ES17-FR66 or via ES20-FR64 .

If the route returned by the API doesn't match your requirements we need to

• identify whether there's a regular option that would tell the routing engine to go for a desired path, e.g. by using shortest/fastest...
• identify whether the reason why a route doesn't look as expected is triggered by some legal background ("we are forbidden to drive there") or whether it is a "other routes are preferred by the business because..." - e.g. because we don't want to drive on steep slopes in winter time or even through the whole year

If the second motivation applies we could offer the custom road attributes feature...

I used the showcase:CustomRoadAttributeScenarios to block several major, improper roads in the Pyrenees.

The routing then performs the expected detours.

Bernd

[Bernd Welter]

Here's an addendum to the approach with the segment blockings:

• The costs for violations apply for each contiguous group of segments. This usually works great in small, local areas. But with major areas such as alps or pyrenees with a sparse routing network the detours to adjacent valleys are so expensive that violations are tolerated.
• Therefore it makes sense to create groups of unconnected segment blockings which will cause the violated transit to be too expensive compared to the detour.

If a detour around a single segment is way more expensive than a single violation the routing stays on the violated pass. Furthermore in this example also the nearest alternative pass would cause violation costs.

several non-connected segments are blocked. Violating them for a transit would cause massive additional costs for the aggregated violations. Therefore a detour applies.

Thanks for the advice, Sebastien!

Bernd