I'm looking for a method in QGIS to clean the topology of a highway dataset from OpenStreetMap that contains bridges and tunnels.
I would like to break ways at every intersections which is represented by a node (more a vertex than a node since we speak of topology I think) but not where a way crosses another way without a common node ( which should involve a tunnel or bridge regarding the OpenStreetMap topology model).
Regarding what I have tested, it seams that v.clean can't do it and I can't find another method.
The best method I can think of is to filter bridges and tunnel before doing the v.clean but it is not perfect. Other method I have tested is to distinguish bridges and tunnels connected and disconnected to the network by playing with cross and touch spatial queries but it is not perfect too.
May be another way to explain my problem is : I'm looking for a method to clean topology of a network only on nodes.
v.clean
withtool=bpol
does the job but it is not clear (for me may be because of my English) in the manual. I am going to do more tests before answering my question.