[Tagging] Feature Proposal - RFC - parking (redux)

[M∡rtin Koppenhoefer]

2011/3/18 Flaimo <flaimo at gmail.com>:
> just relying on a surrounding amenity=parking area without a relation
> also has another flaw: underground parking. basically nobody maps
> underground parking facilities as areas with layer=-1. all of those i
> have seen so far in OSM are mapped as nodes at the entrances. and that
> is the problem. underground parking facilities often have more than
> one entrance. right now, each entrance is interpreted as its own
> parking lot. the relation would group them together to one parking
> facility.


Yes, it can be a possibility (and indeed to group nodes a relation
different then multipolygons is needed), but I'd consider this not the
better approach, as a simple area will be more useful then a relation
with some nodes (and easier to map as it would be "mapping as usual"
instead of "exception"/new relation type). Reasons that the area
currently is not used a lot this might be:
- the exact size and position are not known to the mapper (I'd suggest
to map it approximately, still better then nodes)
- the renderers currently don't support underground buildings in a
nice way (will maybe change in the future), maybe even render them not
distinguishable from surface buildings (which is discouraging).
- documentation in the wiki suggests that a node is sufficient, or is
not very specific. (could be changed)

Btw.: you wrote that "nobody" mapped underground parkings as area with
a layer=-1 but I found that people indeed do it.
I found 90 nodes with parking='underground' (of which 4 with layer=-1)
in my extract versus 40 polygons (of which 15 had layer=-1), so almost
one third of the underground parkings in my region are indeed mapped
as areas.

This is opposite to all amenity=parking (8000 nodes vs 16000 polygons)

cheers,
Martin