Terminology and tagging
Folks on IRC seem to
hate initialisms like "asl" or "atm". We can probably/should probably move instances of this to cycleway=advanced_stop or something like that at Some Convenient Point. Sound fair? --achadwick 13:58, 11 April 2011 (BST)
- Just tried mapping a few, and seemed more natural to tag them highway=advanced_stop than cycleway. They really are a feature of the whole highway rather than just affecting cyclists. It does seem slightly odd to be tagging the back of the box with the advanced_stop_line when presumably that is really the line at the front of the box. Won't do more for now as its only something I've noted in passing. -- SK53 22:29, 11 April 2011 (BST)
- Yeah, like the main page says, don't map the line at the back of the box, map the one at the front since that's more useful to the road users the things are for. Maybe I should make this a bit clearer, though the current text is "ideally level with the stop line at the front of the painted box". Is that unclear or too parochial? It's legally a "stop line" in the UK at least. I may need to make a picture (any freely available and clear sat photos or overheads we can use in this context?) --achadwick 15:26, 12 April 2011 (BST)
- Arguably the one at the back of the bike area is a highway=stop (even though that's documented as being about stop signs, which frankly aren't the things carrying legal force :-/) --achadwick
- Definitely agree that it should eventually be a foo=advanced_stop rather than a foo=asl or a foo=advanced_stop_line. I still think it'd be useful to convey the notions that it's a feature intended for cyclist use (just how many other modes have such a facility, really? any counterexamples?), and that the line is in front of the general one. --achadwick
- If its at the front of the box, then it logically should be on same node as traffic_signals, but not infrequently that is shared with a crossing. Instead of reading the wiki, I just thought I'd go & see what was natural to tag (as a non-cyclist). If you want it at the front of the box then I'm afraid it's more sensible to use the relation instead of converting a junction with one traffic_signal node to 4 nodes & adding stop lines. ASL's affect motorists because the location of the traffic signals is not the point to stop. Unlikely to use a GPS/SatNav for this, but it is apparent to the non-cyclist. Decent Bing imagery around Canning Circus, Nottingham (I probably have ground photos too). -- SK53 16:20, 12 April 2011 (BST)
- The problem with sharing the node with the traffic signals is that you lose information, such as whether there is an ASL in one direction but not another. Smsm1 15:22, 7 November 2012 (UTC)
I found advanced stop lines for other vehicles than bicycles, in Barcelona it seems quite common to have them for motorcycles: . See also this comment on stop lines in Japan: [] So, I doubt that cycleway=* is a good tag for this, it should imho be more like highway=stop_line with additional access tags. Theoretically there could be one for motorcycles and one for bicycles (but I haven't seen one yet). Unfortunately, highway=traffic_signals can not be on the same node anymore because of two highway=* tags. --Jlcod (talk) 13:59, 5 July 2016 (UTC)
Way and Area forms for wide highways
There might be some benefit in allowing this for advanced stopping areas or lines on wide highways using the area=yes convention. Not sure how we'd go about this yet. Feel free to try things out though...
Keeping a "line" term out of any future expanded is probably wise since we don't quite know what form this might eventually take. --achadwick 14:03, 11 April 2011 (BST)
Is this really a problem in practice? Is it sufficient to just have the node be near the junction and on the same way, or are there concrete corner cases? Obviously I'd prefer to tag a few more and eyeball the road layouts, but can anyone find a good real-world example of a junction where a simple nearest-junction approach fails? --achadwick 15:50, 12 April 2011 (BST)
Possible corner cases to consider. If anyone can paste a concrete example, it's back to the drawing board... --achadwick 15:50, 12 April 2011 (BST)
- An unrelated junction midpoint is closer to the ASL front line than the midpoint of the related junction.
- Junctions with no clear midpoint concept (is that even a thing?)
- Not-a-road-junction cases. Pedestrian crossings or railway level crossings probably need to be documented...
One possible workaround should this tagging scheme fail: make the tagging way-direction-dependent: advanced_stop[=:]forward[=yes], perhaps... --achadwick 15:50, 12 April 2011 (BST)
Not-a-road-junction: https://www.openstreetmap.org/node/281619158 is a crossing (pedestrian+cycle across a road) with ASLs on the road. Good image at https://www.mapillary.com/app/?pKey=1eNy7myml6Wgt1VqazqWTw&focus=photo&lat=51.461303999999984&lng=-0.1461500000000342&z=17 --Ecatmur (talk) 08:51, 20 July 2017 (UTC)
And are we overthinking it?
Do we even need to associate (highway, ASL, and the physical reason traffic might stop) in some ghastly turn-restriction-like triple or relation? Is it sufficient to apply the KISS principle and say "bikes make have to stop here, but will get a head start"? --achadwick 15:50, 12 April 2011 (BST)
Do not use abbreviation as value
Please, do not use an abbreviation as value. This is stated by many discussions on tagging@osm. We should switch to advanced_stop_line.--Skyper 18:08, 28 October 2013 (UTC)
- This is covered in the earlier discussion. Yes, we probably should avoid abbreviations. I'd prefer cycleway=advanced_stop because it's neater, terser, unabbreviated, unambiguous, and closer in spirit to highway=stop. If you want to correct it in the database and then document that change in the wiki, please do. --achadwick (talk) 15:11, 29 October 2013 (UTC)
Why as a node?
To me it would make a lot more sense to tag this as cycleway=bike_box or cycleway=headstart_for_bicycles on the way, instead of a node (which node anyway?), in analogy to cycleway=lane/track. The way needs to be split, maybe twice, then. But at least it's mapped very explicitely that way. Alternatively as cycleway=advanced_stop_line.
- I agree that it would make more sense to tag a way - but maybe in combination with a node for the stop line. How about tagging this section of the cycleway with <cycleway:side=stop_area> and the actual stop line with <cycleway=asl> (or to make it more descriptive: <cycleway:side=stop_line>? The tag <cycleway=stop_line> could also be used in cases where the stop_line is not really advanced, just to indicate where cyclists have to stop. --Biff (talk)