[EMAIL PROTECTED] wrote >Sent: 13 March 2008 3:34 PM >To: talk@openstreetmap.org >Subject: [OSM-talk] How do we tag passing/slow lanes? > >Hi, >I'm a new comer working in/on Southern Alberta. Just getting to grips with >the range of tags available, and have a question about passing/slow lanes. > >By passing lane, I mean a section of non-segregated road which has an >additional lane in one direction. This is often on an up-hill section >where larger traffic would slow, however this is not always the case. Here >they have built a series of passing lanes on Highway 3 (Crowsnest Pass to >Lethbridge) instead of building segregated lanes. >
To annotate the physical: Break the way at the start and end of each passing section and tag with lanes=2 for the normal sections (assuming its normally a two lane undivided highway) and lanes=3 where the way includes the passing lane. This doesn't deal with solid white line restrictions that might be present along sections of the way, but then we don't really attempt to get to that level of detail for normal roads at the moment anyway. >The same situation can occur where you have turn left/right turn lanes at >junctions, which is very common here. > > >The only suggestion I had was to set lanes to '1+2', which would mean 1 >lane in the forward direction (of the way) and 2 in the reverse direction. That's not a particularly good idea because anyone could flip the way direction easily enough and then it wouldn't be valid. > >If by convention the user was to use the 'normal' width as the first >parameter then renderers which did not support this extra feature would be >able to easy parse out the data. This obviously means sections of road >might have the opposite way direction, but I don't think that matters. generally speaking the majority of maps don't try to be too clever and show streets at the real width as it physically varies. Trying to get too smart with rendering will probably lead to more errors through missing or inconsistent data anyway so it's probably not going to be worth it. > >It would also require some fine tuning of which lane merged back into the >normal flow, ie. did the 1st or 2nd lane have to merge? > Do we really care? >Comments? > >Cheers, >Mungewell. > > >_______________________________________________ >talk mailing list >talk@openstreetmap.org >http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
