[Tagging] Feature Proposal - RFC - Crossing cleanup and deprecation

[Minh Nguyen]

Vào lúc 15:18 2022-11-28, Martin Koppenhoefer đã viết:
> crossing:markings is just about this, road markings, and while crossing_ref=zebra wasn’t documented for a long time, people that added it around here told me it was about the presence of road markings as well.
> 
> Crossing=zebra is about a zebra crossing, it implies also vertical signs- in some jurisdictions and some conditions at least - and it implies that there aren’t traffic signals.
> Neither crossing:markings nor crossing_ref (as it is applied here) say anything about traffic signals. Here you will usually have zebra markings on signal controlled crossings, but they aren’t zebra crossings of course, still crossing:markings=zebra applies. And many of them have the crossing_ref=zebra tag (I ignore this tag, it does not follow any consistent logics here, definitely not a tag I would want to base navigation decisions on). Maybe they are when the signals don’t work (not sure about it, the law here requires vertical signs for zebra crossings, unless at road intersections).

As you may be aware, iD used crossing=zebra for its Crosswalk preset 
between 2014 and 2019, during which the vast majority of occurrences 
were added. [1] So whatever it may have originally meant has already 
been diluted to the point that you're probably better off supplementing 
the tag with something more explicit if you care about the additional 
nuances you're describing here. In general, crossing_ref=* is supposed 
to be a localized, holistic approach to classifying crossings. If 
crossing_ref=zebra is itself too diluted, then perhaps you could use a 
different value. Unfortunately, it's a Monday, so all I can think of at 
the moment is crossing_ref=zebra2. XD

Even if it weren't for iD's long-gone preset, I don't think an 
ostensibly global tag should be defined based on the narrow provisions 
of a specific country's laws. But as you're only defending 
crossing=zebra from deprecation, rather than promoting its usage over 
less provincial tags, an alternative to deprecation would be to give up 
on crossing=* having any machine-readable meaning on its own and allow 
it to be an any-tags-you-like situation, similar to ref=* on ways.

[1] https://wiki.openstreetmap.org/wiki/Special:Diff/2396877#iD
[2] 
https://wiki.openstreetmap.org/wiki/Proposed_features/Crossing_signalization

-- 
minh at nguyen.cincinnati.oh.us