This is closely related to issue #926.

We're creating routes based on GPS data. Occasionally, the GPS indicates that a start or end location is situated in a place where there is no entry or exit, an island of sorts as described in #926, when the real location is probably on a main road a few meters away.

Is there any way to route between what I would call the "nearest viable point"? In effect, this would mean detecting when a point cannot be routed to and scanning for the nearest point that can be reached.

I believe this is similar to the z parameter, but adapted for when the nearest location cannot be routed to.

Example failing query to the API:

http://router.project-osrm.org/viaroute?loc=40.4221205,-3.707557599999973&loc=40.4576797,-3.692164400000024&z=10

Thanks for any advice!