On Fri, May 6, 2011 at 10:02 AM, Tobias Knerr <o...@tobias-knerr.de> wrote: > Some physical keys could be added to the list, such as width and lanes. > However, I wonder whether a total ordering is the best approach. > > Look at the physical descriptions from your example (bridges, tunnels, > surface). They are quite independent from legal limitations (access, > oneway, turn restrictions, ...). As you have already hinted at, what you > want to map first really depends on the applications that you have in > mind: many renderers, for example, don't use turn restriction data, but > do use bridge attributes; for routing the situation is reversed. > > I could use other examples, but the bridges are what I immediately > wondered about when reading your list. When I started OSM mapping, > bridges would naturally be among the first things I would map. The > bridge/tunnel attributes are also much older historically than turn > restrictions, and adding them requires a lot less editing skills than > relation handling. >
I thought about that same issue regarding bridges and tunnels, which is why I changed "for routing" to "slight orientation towards routing", you're exactly right about the application dependence. Tunnels and bridges are one of the more satisfying things to map, and so it's one of the first things I do. > May I ask why you want to assign numbers to these "levels" at all, > rather than providing a checklist? If it's also intended as a guide for > new mappers, then the complexity of the data structures involved should > also be considered (i.e. things requiring relations should be closer to > the bottom, stuff that just requires adding a tag should be higher up). > My primary goal is to use this for methodically going through all the state routes in Virginia. Other states have pages which focus on creating relations for all state routes, and simply say whether they're "Complete" or not. That got me wondering what complete meant, and of course in this context they mean that all ways which are part of a given route are members of that route relation. Instead of just saying whether a route was "complete" or not, I thought it would be more useful to say that a given route is "completed" to level 1, 2, 3, etc. But your point about a checklist is valid, and it would be nearly as easy and more informative to create multiple columns for bridges/tunnels, oneway, turn restrictions, etc. However even with this it's worth having a logical grouping, with perhaps no more than 10 groups. > The Ramm/Topf/Chilton books contain a suggestion of mapping priorities > (including not only roads, but other features, too). They also group the > features into numbered levels, similar to your approach. It's about time I buy those books! Thanks, -Josh _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
