OpenStreetMap
I was just wondering what the situation with the directionality of signs was.
I've come across a few nodes on roads which are tagged as maxspeed=
Quite apart from the fact that JOSM renders all these as "60", how can a "node" represent a maximum speed ? Surely, you want to know what speed it is in "that" direction and what speed it is in "this" direction.
If you can see the "whole" village, it is obvious which side is NSL and which 30 or whatever.
Is there any convention on which way a sign is facing, and how to have different "text" for each direction, especially when the node is on a way (which has an obvious direction), something like forward:maxspeed=50mph | backward:maxspeed=30mph.
I question the usage of maxspeed tags on nodes anyway, exept as a temporary measure. Surely it is redundant once the ways leading from that node have all been maxspeeded.
How do you represent multiple signs on a signpost, all pointing in different directions ?
How do you do signs indicating "this is the start of such-and-such a village" ? Again, my prefs would be to put them in as a temporary measure and then, when you've got the full set, join them up to make a bounding polygon.
Discussion
Comment from Vincent de Phily on 31 January 2011 at 12:05
I haven't checked the wiki or discussed this anywhere, but my gut feeling is that these tags have nothing to do on a node : they should be on ways and boundig polygons. If you really want a temporary measure on a node, I'd suggest a "fixme=speedlimit 60 northwards from here" or similar.
Comment from Zartbitter on 31 January 2011 at 12:15
Maxspeed is an attribute of the way. It can be unidirectional or bidirectional. Maybe someone wanted to map traffic signs and didn't know how to do it.
Start/end of a village is mapped on a node belonging to the street entering/leaving the village. Use traffic_sign=city_limit and name=.
Joining city limits to a polygon doesn't make any sense because there is no such boundary not even a virtual administrative boundary. City limits on steeets can be everywhere on the streets!
Comment from compdude on 31 January 2011 at 18:06
You have to put the maxspeed=* tag on a particular way to set the speed limit of the road. When the road's speed limit changes, then split the way at the point where it changes and tag the appropriate speed limits for those two ways. You're not supposed to tag it as a node because then it doesn't get attributed to a particular road.
Comment from hkucharek on 31 January 2011 at 21:09
You don't map the sign. For the driver, a sign just gives an attribute of the road ahead and that is what you map. Give a piece of a road an attribute maxspeed=* by tagging it.
Comment from c2r on 31 January 2011 at 23:59
I've only seen maxspeed= on a node where enforcement=maxspeed on the same node.
Comment from Baloo Uriza on 1 February 2011 at 03:00
I believe there should be a space before "mph" based on existing tags and the wiki.