How does Kurviger handle the subtypes of a road that is tagged highway=service in OSM?
Let’s look at this example (it’s only an example! Please don’t simply go and “fix” that road in OSM, I want to talk about the behaviour of the algorithm in general)
As you can see in the OSM info window, this road is highway = service with service = parking_aisle.
Kurviger routes there, but says it might be a closed road, which in my opinion is the wrong thing to show for a parking aisle. Should the Kurviger algorithm know the subtypes of the service roads and only block access to some? Is that even programmable? Is this the reason it was implemented that way, because not all subtypes are distinguishable and Robin wanted to let us drive there but still give a (red) flag that it might be a closed road?
Again: there are several more examples for this in Norway, please don’t go ahead and fix this one without discussing a more general strategy here first
The idea here is that some parking_aisles might be used to access some other roads as well. So access is not blocked, but you get a hint that there might be an issue and you can decide if you want to use it or not.
Hmmm that true, interesting.
So there is no way to distinguish which ones have a connection to only that road where they are coming from? Yeah I think the red “blocked” sign is the wrong behaviour here, since kurviger already has a mental connotation for that. Kurviger usually uses it for things that might be blocked for all traffic - sometimes. But not for roads that are blocked for all traffic at all times.
In the case you described it’s plain illegal to use the parking_aisle as a connection. So wow… maybe in the end it even is the case that this has to be edited. Maybe highway=service is just wrong here, for parking lots that are totally drivable
Yeah I get that this is the best possible kind of “fallback” at the moment, defer the decision to the user. But in a perfect world, the best solution would be to have “normal” parking spaces drivable without that warning and decision making from the user. And to have parking spaces that may be misused (illegaly) by drivers not drivable
Speaking of the highway=service tag, I noticed that routing allows driving on bus lanes. This is quite a specific (and clever) case where city buses run on tram tracks. Normal vehicles cannot access it, the more so because there is a no-left-turn sign there.
Maybe someone skilled in OSM would like to take a look?
I don’t know which tag allows this. I can see: access=no and motor_vehicle=designated… Perhaps something else relevant to Kurviger.
motor_vehicle=designated is definitely wrong, if only buses are allowed. designated is a synonym for preferred
See Key:access - OpenStreetMap Wiki
“designated: A preferred or designated route for the class of traffic specified by the tag key”
A typical case for designated would be: bicycle=designated
In my opinion motor_vehicle=designated should be replaced with bus=designated
Additionally maybe even replace highway=service with highway=busway
Thanks for your concern. You are certainly right, but I wouldn’t want to alter the OSM data at a fairly complicated (downright scary) intersection. I do not have enough knowledge, and maybe there is a reason for this use of tags? In addition to buses, there are also trams, emergency services, maybe a taxi?
Since everything is OK from the Kurviger routing side, I can write to the author of this fragment or simply leave a note.
Yes, doing that differentiation is actually quite hard right now.
If you know the area, please feel free to modify it . Since the designated tag is a common tag for tagging error (designated != destination) I went ahead and removed the tag to fix the wrong tag, but please feel free to improve this for bus routing .
. Since the designated tag is a common tag for tagging error (designated != destination) I went ahead and removed the tag to fix the wrong tag, but please feel free to improve this for bus routing 
.