[Tagging] automated edits seem to remove crossing=zebra drastically

Matthew Woehlke mwoehlke.floss at gmail.com
Thu Sep 17 13:15:30 UTC 2020

On 16/09/2020 20.40, Taskar Center wrote:
> crossing has been a very poor tag because it seems to be the kitchen
> sink for all the questions pertaining to crossings... Many of the
> attributes that get values in "crossing" are potentially overlapping
> and not mutually exclusive, causing a lot of confusion and poorly
> tagged crossings. Nevertheless, specifying crossings is very
> important because it's a highly contested street region.
> The crossing tag has held many values that may overlap, and we should
> once and for all split out all these different tags so we can be
> mapping what we mean and mean what we map. Questions we should be
> answering when mapping a crossing: 1) How is this shared space
> controlled? A crossing is a high risk environment where traversal is
> shared between cars and pedestrians (they are of unequal footing). So
> the type of 'control' and 'right of way' in that space is important
> to specify. 'uncontrolled' is a very bad tag in this direction
> because it has an actual legal, non-intuitive meaning and many
> mappers mistakenly think a crossing that has no traffic signal is
> uncontrolled- so that's a really bad tag. crossing_control= ?

It's also atrocious because it can *only* be verified by survey. As much 
as we prefer surveys, the reality is that a lot of mapping happens just 
from aerials, where crossings (both marked and, in some cases, unmarked) 
can be seen, but signals cannot. As someone who's generated a fair 
number of "uncontrolled" crossings because that was the only "blessed" 
tag, I would much prefer separating the presence or absence of features 
that can be verified in an aerial (marked, unmarked, striped, island, 
...) from whether or not signals are present.

> 3) How can a pedestrian call up the signal and how can they sense
> whose right of way is currently allowed? Is there a call button? Does
> it chirp, speak out,  vibrate?

Id' be careful with this one; I've read that those buttons are often 
placebos. I suppose if we're just mapping whether a button is present or 
not, that's okay, but just because there *is* a button doesn't 
necessarily mean it has to be pressed.


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