Directions say 2nd exit, reality is 3rd exit

Hi. I just used Organic Maps to for directions, and noticed that one roundabout intructed me to take the 2nd exit, when the map clearly showed the 3rd, with the latter being correct. I tested the diections given by openstreetmap.org, and the same instruction to take the 2nd exit was given there. Below are screenshots of the behaviour:

Any idea what goes wrong here? Is it because the roundabout flare is tagged as a service road? If yes, would “unclassified” or “minor” be a more appropriate highway tag?

Service road seams right, as it leads to the parking of a school area. But with OSM and Organic maps both giving incorrect directions, something needs to be changed. When the data seems reasonable, perhaps the routing should be adjusted instead? How would one go about changing that behaviour?

Your link does not go to the specific location so wild guess, does this roundabout suffer ‘shortcuts’, meaning an on and off are connected with the same node of the roundabout? I see this warning frequently on newly mapped ones. There must be separation for the navigator to assess e.g. priority… yield > on > off.

I’m not really sure what’s wrong here (the map is fine), but only OSMR says 2nd exit, while Valhalla and GraphHopper say 3rd.

;Valhalla
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;GraphHopper
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Seems a OSMR problem, GrapHopper and Valhalla say to take the 3rd exit.

EDIT: Mannivu :ninja:

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Issue created for Organic maps here. I could not find a github page for OSMR, so assistance in creating that issue would be appreciated. Thanks for the help in investigating the issue!

It’s OSRM, not OSMR. Open Source Routing Machine. https://project-osrm.org has a link to the Github repository.

It’s possible (just guessing here) that it doesn’t count service roads towards the exit count.

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It actually looks like someone reported this issue years ago:

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The test would be to home in with the end pin, or start pin of the route and move it exit by exit to observe where the counter starts to deviate.

Organic Maps does not use OSRM. It could be that the service road is ignored. Please share a link to OSM object in the related issue.

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Confirmed

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GraphHopper gives for second north south to take the 2nd exit.

That can easily be tested, just change it (temporarily) to e.g. unclassified and try OSRM again.

This shouldn’t be done, the map shouldn’t be changed arbitrarily just to test something.

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… or you can keep on guessing!

correct: first exit

incorrect: first exit
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It is found in the code for Organic Maps at least:

The Valhalla’s OSRM’s and GraphHoppers need a little bit more I put into the A…Mapped on Tuesday, verified, reverified, all is right and in place yet travelling the roundabout wants to take the 5th exit and when the green pin is moved to the white entrance it does it correct, 3rd exit

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Notably this roundabout has not been cut up yet since the bus routes turning from E to NE have not been mapped yet.