Breaking up roads for turn restrictions, changes in the number of lanes etc is perfectly fine.
I've always found it a bit silly to break up roundabouts for route relations, but not everything supports leaving them intact.
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Breaking up roads for turn restrictions, changes in the number of lanes etc is perfectly fine.
I've always found it a bit silly to break up roundabouts for route relations, but not everything supports leaving them intact.
Yes, this is the way(s). You can map nicely where the bus (or any other) route enters and exits the roundabout: https://www.openstreetmap.org/relation/2453566#map=18/33.789672/-118.143028
It's not compulsory, it's fine if you leave it as single circular road. But if you edit a bus route with Relatify it will automatically split the roundabouts to segments like this.
Note that route relation such as bus relations are added sometimes with entire roundabout without splitting it, that is also fine but splitting it is also fine and there is no consensus which is preferable
https://wiki.openstreetmap.org/wiki/Tag:junction%3Droundabout
I think it would be more useful to regard this as a StreetComplete/editor flaw than an OSM flaw.
If you set the surface before the path is split, it's applied to all of them and many desktop editors have some sort of Ctrl-Select/multiselect support that makes this no real hassle.