On Tue, Oct 12, 2010 at 12:04 PM, Colin Smale <[email protected]> wrote: > What layer is the road on which connects the rest of the road network at > ground level (layer=0) to the bridge itself (layer=n>0)? I seem to remember > a discussion about joining ways on different layers..can't remember the full > conclusion but I believe it was that the layer tag is only for rendering > purposes and doesn't imply anything reliably about above/below.
If the road's on an embankment until it reaches the bridge, it's still on the (artificially-raised) ground and hence (implied) layer=0. If anything passes under the embankment it's either a short separate bridge or a tunnel (there's no clear line between the two). Two ways on different layers should not cross, and one could argue that if a node has more than two ways all should be the same layer. But there's no way to avoid a change in layers along a way (such as in a trefoil knot). _______________________________________________ Tagging mailing list [email protected] http://lists.openstreetmap.org/listinfo/tagging
