Routing is completely broken if you change the source so that merging is also done for roads in res 24, so it must be handled with care,
The LineMergeFilter does not care about routing nodes. That should be the reason why routing fails when using it at res 24.
yes, but not the only one. I created a version that made sure to split roads so that they start and end with coordNode, but that (alone) did not help.
Anyhow I did not yet fully understand about the relation of the routing network (NOD) to the map data at resolution 24. Are there any ids that are shared? When selecting a street how does the Garmin find the correct entry into the routing network?
I wish I could say that I understand it :-O
but we may also allow it again for res < 24.
Unless there is a concrete example or a concrete explanation why it shouldn't be allowed I would allow it.
yes, I agree.