[Talk-us] Park Boundary tagging
steveaOSM at softworkers.com
Mon Mar 4 03:04:53 UTC 2013
While Greg describes what "might be," I'll describe what "is." I'm
only scratching a surface or two as I do.
I described uploading both Forest Service boundaries for National
Forests and Wilderness areas. As we were using USFS data from a
particular source: source=http://fsgeodata.fs.fed.us/vector/lsrs.php
For Wilderness, these tags:
And change WILDERNE_1 tag to:
name=Name of Wilderness
For National Forests, these tags:
Adding a tag like:
is optional, but park:type is a tag gaining widespread use (starting
in California) to distinguish between national_forest, state_park,
state_beach, county_park, city_park, etc. When doing this, use the
correct value, with underscores for spaces, and separating with
semicolon any conflated areas (such as national_forest and
wilderness). For example, you might add (for a National Grassland):
>I suggest that the tags for parks/etc. be defined so that if there are
>no boundary tags, everything still makese sens. (I'll further suggest
>that once this is done, there is no need for boundary tags.)
I'm OK with positing that we need not use the boundary tag. But then
what will render a boundary, if any? Yes, we can point to mapnik
rules that say "if name key of a polygon or multipolygon = a value,
display it" being the reason that you see black text saying "Sequoia
National Park." But it is key=value pair boundary=national_park that
renders pretty green text out to z=6. We also notice that if
"leisure=park" mapnik renders a nice light-green fill color or if
"landuse=forest" we get dark-green with little trees. Likewise
leisure=nature_reserve gives us the "little NR" overlay. Yes,
landuse=forest (on national forest) and leisure=nature_reserve (on
wilderness) yields "dark-green + NR" (to pleasing effect) and
well-represents a wilderness inside of a national forest. But the
edge between these is difficult to see without a boundary
(=national_park) tag. So, I like using it, and think it is a good
idea to do so, as it sharpens that boundary where it is appropriate
to see that boundary. But I am open to "better" tags to achieve
these or similar desired results.
> landuse=conservation (because at least a co-primary purpose is to
> preserve the land for the future, and usually this is primary.)
> leisure=nature_reserve (because a co-primary, but really not
> quite-as-high-as-conservation is to allow access to the public)
The landuse and leisure keys are separate, and they have multiple
possible values. Before we get into the specifics (or maybe AS we
get into them, so that we may untangle them properly) let us ask
first if there are any mutually exclusive values.
>Then we get into tags that refer to the administrator of an area.
I will temporarily ask us to conflate "administrator" into
"administrator" + "operator" + "ownership" as it may be possible that
we can agree upon "certain tag groups for certain semantically
identical objects." (Though I could be wrong). Tangled up is
"admin_level" but that may (strongly?) imply boundary=administrative.
I'd like to see what happens with mapnik rendering when admin_level
is used with other boundary values, like boundary=national_park.
Maybe I'll play a bit with some boundary values and admin_levels,
non-destructively of course. I just want to see what mapnik is
doing, vs. what we mean to happen.
>And of course name of the park.
Agreed, this seems fairly straightforward as a text string in the
name= key. Just a caution that what paints the name of an object
(polygon, multipolygon) might be distinct from what its "boundary
tags" (if any) do.
>My bias is that the nature of the land use is more important than
>the identity of the manager.
>Another similar area is a "wildlife refuge". Ones that allow humans are
>perhaps appropriately tagged as above. Ones that do not allow humans as
>perhasp landuse=conservation and some other special wildlife_refuge tag.
So, a short catalog for possible tags to "untangle semantics" regarding parks:
landuse [forest, wood, conservation...]
leisure [park, nature_reserve...]
name=[Text String for name of park]
protect_class=[many alphanumeric values possible, among them 1b=US
Wilderness, 6=US National Forest)
ownership=[national, state, county, city, neighborhood_association, private]
park:type=[state_park, county_park, city_park, private_park,
state_beach, county_beach, national_forest, national_wilderness,
state_wilderness, national_monument, state_historic_monument, many
I already see a slight problem with landuse=conservation because it
could be all meadow, all wood, all forest, all farm... and yet ANY or
ALL of those can ALSO still be landuse=conservation. We'll need to
solve this, as it is a clear slash between syntax and semantics for
exactly that/those reason(s).
I'm not even touching "boundary" (to possibly paint/render a boundary
where otherwise an 'edge' just gets a fill-color without a boundary
-- as noted in the case of leisure=park simply rendering light-green
fill with no 'border' around it, or how it is nice to see the
distinction of "little trees" vs. "no little trees" when NR vs. not
NR are swimming in a large landuse=forest).
More tags, more possible key-value pairs: keep going! We are rolling now!
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