[Tagging] OSM is a right mess (was: Craigslist OpenStreetMap Rendering Issue)

David Fisher djfisher81 at gmail.com
Fri Jun 5 09:33:15 UTC 2015


On Fri, Jun 5, 2015 at 12:33 AM, pmailkeey . <pmailkeey at googlemail.com> wrote:
>
>
> On 4 June 2015 at 10:46, David Fisher <djfisher81 at gmail.com> wrote:
>>
>> On 04/06/15 00:48, pmailkeey . wrote:
>> > A value of residential here  seems to need a key to identify whether it
>> > relates to a building or landuse. However, you suggest
>> > building=residential as possibly being redundant. In fact, I'd turn this
>> > on its head and make landuse=residential (with the exception of moles)
>> > redundant. The only residential landuse is directly under a building but
>> > by using landuse=residential, such areas cover gardens and highways -
>> > which are clearly not residences.
>>
>> The tag is "landuse = residenTIAL", not "landuse = residenCE".  In
>> other words, as Lester Caine says, it demarcates a residential zone,
>> i.e. an area containing (mostly) homes plus associated infrastructure
>> such as parks, gardens etc, as opposed to an area of shops, offices,
>> industry, farmland, or whatever else.
>>
>> I agree with some of your frustrations about the project, but I think
>> you sometimes jump to negative conclusions too quickly.
>> "landuse=residential" is clearly useful, and equally I don't see that
>> "directions=xx" is any improvement on "oneway=xx".  Pick your battles!
>>  (e.g. "amenity" I agree is a right mess.)
>>
>
>
> LOL !
>
> The issue with the 'oneway' key is that the key itself contains 'data'
> relating to the value. Oneway without a value would imply =yes whereas
> building without a value (or =yes) would give data independent of the value,
> IYSWIM
>
> building=
>
> hospital=
>
> The latter describes the building without the need for a value.
>
> I note your TIAL v CE above. Why do we need to know what the landuse is in
> any case ?
>

I do see what you mean.  I think the difference is that "building = x"
in some sense defines the presence of the object, as does "highway =
x" on a way.  So, if "building = x" is not set (presumably on a
"circular" way), or if "highway = x" is not set (presumably on a
"linear" way), then those ways are just collections of nodes, nothing
more.  But "oneway = x" defines a *characteristic* of a way.  A way
must fundamentally *be* something (e.g. a building or a highway), but
it may nor may not have any number of characteristics which don't
alter that fundamental *being*.  The only sensible way to deal with
*characteristics* (other than insisting that every way has hundreds of
tags) is to assume defaults.  "oneway=no" (that is, there are no legal
restrictions on the direction in which one must traverse a way) seems
a sensible default to me, and therefore if the "oneway" tag is not
set, the way defaults to two-way.  As I said in a separate post,
though, "oneway" does not imply anything about number of lanes, who
has priority, and so on.  Does that make sense?  (there are always
exceptions, of course, but that's how I see the overarching
philosophy.)

As for "landuse=residential" -- I agree that we could probably do
without it.  But it does add to the readability of the map, especially
at low zoom levels, as it enables you to see at a glance where places
are and how big they are.  Personally I'm an advocate of covering the
majority of the map (not necessarily 100%) with some form of landuse
area, e.g. residential, industrial, grass/meadow/parkland, farmland,
etc. -- though I appreciate that not everyone shares that view.

Cheers,

David (user Pgd81).



More information about the Tagging mailing list