Frederik's description of colored polygons made me think of the French OSM instance, which can display admin level, ie http://layers.openstreetmap.fr/?zoom=5&lat=39.9597&lon=-78.77311&layers=0B000FFFFFFFFFFFTFFFFFFFFFF
Regarding Native American reservations, while there "is no consensus" there are a couple alternatives to admin_level (using boundary=* instead) mentioned here: http://wiki.openstreetmap.org/wiki/United_States_admin_level#Native_American_reservations On Tue, Jul 11, 2017 at 2:03 PM, Frederik Ramm <[email protected]> wrote: > Hi, > > On 07/11/2017 08:18 PM, OSM Volunteer stevea wrote: > > I'm glad Adam brings up the topic of Gores, as I'm also unclear on how > such "holes" get "punched into" larger (multi)polygons via tagging. For > example, I am "sort-of-sure" (but not positive) that in Vermont, a "gore" > (or grant, location, purchase, surplus, strip...usually the result of > "leftovers" from survey errors) get a tag of admin_level=4 to accurately > reflect that the governmental administration happens via state-level > bureaucracy. > > I think there might be a misunderstanding here and I would like to chip > in before this gets out of hand, even if I don't have any specialist USA > knowledge: > > If you have an admin_level 4 entity - like a state - then the boundaries > with admin_level 4 are the outer demarcation of that, i.e. they separate > the area where the state is responsible from the area where the state is > not responsible. > > The only reason to have an admin level 4 boundary inside a state, would > be if there was somehow a piece of *federal* territory inside the state. > Only then would the state have a "hole" in it that would be tagged with > admin level 4! An area inside the state that is state-governed because > of a lack of admin_level 5+ entity does not need its own boundary. It is > defined by the boundaries of the admin_level 5+ entities that surround it. > > > without using a multipolygon relation, > > You will be using boundary relations which are practically identical to > multipolygon relations. Any attempt to create a "lower 48 states" > polygon without relations would hit the 2000 node limit. > > > is it correct within OSM to tag, say a very large "lower 48 states" > polygon with admin_level=2 AND ALSO tag admin_level=2 on, say, a > national_park inside of it > > That would only be correct if the national park was *not* part of the > lower 48 states but somehow part of another nation. > > I'm not 100% sure what you want to achieve but think of it like coloured > polygons. If you have an admin_level 2 area for the USA, think of that > as one colour, and then you have a lot of states, each with a different > colour. In those areas where the "USA colour" shines through, because > they're not covered by any state, that's automatically federal territory > and you do *not* want an admin_level 2 boundary surrounding that > (because then not even the "USA colour" would shine through, there would > be nothing there). > > > Guidance by knowledgable people with real answers might guide us on a > number of these situations, not just "Gores" (et al) but other kinds of > "hole" tagging without multipolygons. > > If you mean not only "without multipolygons" but "without boundary > relations" too then I think you should stop right here and leave it to > people who can work with relations. > > Bye > Frederik > > -- > Frederik Ramm ## eMail [email protected] ## N49°00'09" E008°23'33" > > _______________________________________________ > Talk-us mailing list > [email protected] > https://lists.openstreetmap.org/listinfo/talk-us >
_______________________________________________ Talk-us mailing list [email protected] https://lists.openstreetmap.org/listinfo/talk-us
