[Talk-us] Park Boundary tagging

stevea 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:
leisure=nature_reserve
boundary=national_park
boundary:type=protected_area
protect_class=1b
protection_title=Wilderness
ownership=national
And change WILDERNE_1 tag to:
name=Name of Wilderness

For National Forests, these tags:
landuse=forest
boundary=national_park
boundary:type=protected_area
protect_class=6
protection_title=National Forest
ownership=national

Adding a tag like:
park:type=national_forest;wilderness

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): 
park_type=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]
boundary=[administrative, national_park]
boundary:type=[protected area]
protect_class=[many alphanumeric values possible, among them 1b=US 
Wilderness, 6=US National Forest)
protection_title=[]
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 
others]

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!

SteveA
California
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