[Tagging] Cartpath RFC

[Minh Nguyen]

Vào lúc 16:55 2020-12-23, Paul Allen đã viết:
> On Thu, 24 Dec 2020 at 00:47, Mike Thompson 
> <miketho16 at gmail.com 
> <mailto:miketho16 at gmail.com>> wrote:
> 
> 
>     If I was on a golf course and I saw a sign that said "cart path", or
>     I was looking at a map specifically of a golf course, I would know
>     what "cart path" meant based on context.  If I saw a general map
>     with the term "cart path", or if the term came up in general
>     conversation, I either wouldn't know to what it referred, or I would
>     assume it was a path for animal drawn carts as another person posted
>     in this thread.
> 
> 
> Those were my thoughts, too.  But then I looked at the proposal.
> In the context of golf=cart_path there is no ambiguity.  I expect
> others may object to the golf key rather than the highway key,
> but with the golf key it's not ambiguous.

As of writing, the proposal is to deprecate the golf=cartpath tag that 
had previously come into use. [1] As a non-golfer who had nonetheless 
dodged plenty of golf carts on a university campus, I would find the 
tagging more intuitive with "golf" somewhere in there. But it doesn't 
have to be in the key, and good documentation and editor support can 
mitigate confusion with other kinds of carts.

In 2021, look out for a bestseller history of golf cart paths in OSM, 
but in the meantime, here's an attempt at a concise, abridged, blameless 
summary:

* highway=path/track/footway variously used ad hoc for years
* golf=cartpath (by itself) introduced as an editor preset to 
consolidate usage and distinguish from walking paths [2]
* Game renderer adds support for golf=cartpath [3]
* Mainstream renderer declines to support golf=cartpath per se [4]
* Editor preset modified to combine golf=cartpath with highway=service 
to work around lack of renderer support [5]
* Game players use the editor preset quite heavily to improve gameplay
* Routing issues occur due to this usage of highway=service breaking 
longstanding assumptions [6]
* Proposal to deprecate highway=service golf=cartpath in favor of 
highway=cart_path [7]
* Proposal adjusted to highway=service service=cartpath to reuse 
existing concepts
* Proposal adjusted to highway=cart_path in light of routing concerns

In parallel, the golf_cart=* key has also come into use, but that's just 
an access restriction key, not a primary feature tag that describes the 
physical infrastructure.

I've left out a lot of details, but hopefully this helps get people up 
to speed about why the proposal takes the rare step of introducing a new 
highway=* value. There's an interesting tension here between the needs 
of editor, renderer, and router developers, but hopefully an amicable 
solution is possible.

[1] https://wiki.openstreetmap.org/wiki/Special:PermanentLink/2076308
[2] https://github.com/openstreetmap/iD/pull/5862
[3] 
https://github.com/chadrockey/TGC-Designer-Tools/commit/e73c663ea1f3204e089cdcded67b9c629166e64e
[4] https://github.com/gravitystorm/openstreetmap-carto/issues/3734
[5] https://github.com/openstreetmap/iD/issues/6165
[6] https://github.com/openstreetmap/id-tagging-schema/issues/48
[7] 
https://wiki.openstreetmap.org/wiki/Proposed_features/Tag:golf%3Dcartpath

-- 
minh at nguyen.cincinnati.oh.us