On Fri, Sep 3, 2010 at 9:59 AM, John F. Eldredge <[email protected]> wrote: > The problem is that, even if you have a tag on the shared way indicating "use > this only for zoom X or below", and tags on the separate ways saying "use > this only for zoom Y and above", there are likely to be some rendering > programs that will show all three ways, leading to confusion.
Let's not assume all implementations of any new idea will be faulty :) Similarly, if the possibility that an existing renderer will badly render some new tag is considered a blocker, then OSM is essentially already dead. We're not at the stage where backward compatibility is essential, IMHO. That said, I can think of ways to implement such an idea while maintaining backward compatibility. Let's say three are three ways: A: north bound train track B: south bound train track C: placed between A and B, to represent the higher level abstraction of the train line, as opposed to the individual tracks. A: railway=rail B: railway=rail C: railway=train_line (or some new, unused tag) relation Z: type=grouping grouping=train_line Any existing renderer would not render C at all. Any renderer (or other tool) that added support for railway=train_line, would presumably also add support for the relation. Remember, this is all just a hypothetical example, not just about train tracks. I imagine there are other examples, though I don't have any in mind atm. Steve _______________________________________________ Tagging mailing list [email protected] http://lists.openstreetmap.org/listinfo/tagging
