these cases are not covered by the splitting algorithm at the moment:
* typicall, only a part of the roundabout should be part of the resulting route
* when multiple routes meet at a roundabout coming from different angles, the roundabout must be split at any of those entry/exit point simutaneously, such that all routes remain correct
as a workaround, a mapper can remove the route relation(s) from the roundabout, split it accordingly and then re-add the respective parts to the relation(s) again.
Martin Raifer
82af60115d