On Jan 17, 2008 3:39 PM, Martin Trautmann <[EMAIL PROTECTED]> wrote: > Karl Newman wrote: > > > It seems to me we're going about this all wrong. Instead of splitting up > > ways just because any of its attributes change (or to break it up for a > > route), it seems like a way which denotes the same street (or other > linear > > feature) should be as long as possible. Then we could hang attributes on > > subsections of it: i.e., for way 1234, the speed limit from node 5522 to > > node 5595 is 100 km/h. Or, way 1234 is a part of route "blue bus" from > node > > 9553 to node 2558. Relations could accomplish this, but they don't have > a > > rigorous structure to enforce all the parts/data integrity. > > It sounds much more reasonable. Sinces ways are derived from the nodes, > it should be more reasonable to add the speed limit to the node itself, > but then including a direction in order to find the start of a speed > limit. However, this would require a matching end designation, such as > maxspeed = default > (or null or "-"...) > > A reasonable assumption is that the matching speed limit in one > direction is the end of a speed limit in the opposit direction. There > may be many exceptions where speed limits apply for one direction only, > or where start and end differ. > > Merging segments by name and moving tags from segments to nodes could be > done by a conversion script automatically. > > - Martin >
I don't think it's a good idea to tag these sorts of things directly on nodes, because nodes can be shared between different ways. That's why I was suggesting relations, but it seems to require a more rigorous structure. Maybe it could be a special type of relation called a sub-way (hee) or way-section (I'd hate to use the word segment, even though it's apropos) which designates a particular part of a way. That would allow the editor tools to deal with it in a uniform way (ensure the data integrity). It might also be useful to be able to designate a single node in a way with a similar type of relation (I'm specifically thinking of house/street numbers). Basically looking for slightly more structure to a certain kind of relation. Karl
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