On Mon, Apr 29, 2019 at 9:05 AM Greg Troxel <g...@lexort.com> wrote: > The other case is a large area with subareas that are each clearly one > or the other. Consider: > > 1000 acre parcel, almost entirely forest in a natural state, with dirt > hiking paths > > a 40 acre sub-piece of this on the edge, that is different: > - paved parking lot > - visitor center / bathroom building > - grass and a few trees (city park like) > - picnic tables, grills > > probably there are different rules for the two pieces. Dogs might be > allowed in the 40-acre chunk, but not in the larger forest, for > example. > > the entire thing is called "Foo State Park", owned by a state > government. Legally it is one parcel, and run by the same state > agency. > > I think the basic issue is that we tend to focus on the larger > definition of area and think we must give it one tag, so we frame the > question: "Is this 1000 acre place a =park or a =nature_reserve?". > Stepping back, I see a park and a nature_reserve as separate and related > things. > > So, I'd be in favor of having a way on the parcel boundary, and another > denoting the park-type sub-piece, calling those outer and inner and > tagging: > > outer: name="Foo State Park" > inner: leisure=park > relation wtih outer/inner: leisure=nature_reserve > > Or, perhaps not having a relation and putting leisure=nature_reserve on > the outer, with the expectation that renderers/etc. will resolve the > overapping landuse to the smaller geometry. > > (As I see it this applies to many National Parks too, but we don't worry > about that because we just call them national_park.)
That's more or less what I've been doing - tag the outer ring, but without cutouts for the inner ring(s). (It's also slightly more complicated than you describe, since the developed areas are frequently, if indeed not usually, on the margin of the larger park, but I do understand multipolygon topology and can deal with that case readily as well.) There's nothing wrong with embedding a protect_class=1b or a protect_class=4 within a protect_class=2. The reason for avoiding cutouts is to make it clear what is and is not part of the named park. Many of the parks that I deal with have private inholdings that are not part of the park but may be completely surrounded by it. Those do get cutouts. I haven't even attempted yet to map the strange intermediate beasts like public-access conservation easements - common on lumber-company land - or private leaseholds of public land - common to allow the larger parks to embed facilities like youth camps that restrict public access. I'm doing what I can manage! The smaller state parks - the thousand-acre type that you contemplate - are often not what IUCN considers to be protected areas, and so I've taken to using protected_area tagging, but with protection classes such as 21 (which woud be accompanied with 'protection_object=recreation'). That doesn't render, so as a stopgap, I've been tagging them 'leisure=nature_reserve' or 'leisure=park', whichever seems to fit, recognizing that further developments are likely eventually to make the dual tagging unneccessary. https://www.openstreetmap.org/relation/6442393 is typical. What I struggle with is are more complex situations - that may always necessitate some 'abuse' of tagging. The thousand-acre park with a forty-acre developed section is handled quite nicely with your scheme. When you have a 'park' comprising hundreds of thousands, or millions of acres, operated in public-private partnership, things start to break down. This is true of New York's two huge parks; of the USA's larger National Parks; and of US National Monuments, National Forests, and BLM recreation lands. The outer ring - the legally designated area - may not really enclose anything recognizable as a 'park', while the stricter 'park' land management may be somewhat diffuse, in many discrete protected areas. The larger area is also protected, but limited sustainable development is often permitted. Looking at the IUCN definitions, the only class that fits these large parks is '2' - 'national park'. IUCN, like our Wiki, doesn't actually require that 'national park' be constituted by a national government. It simply embodies a hidden assumption that only a nation-state has the resources to constitute one. leaving the bigger state-defined facilities in terminologic limbo. Another odd case that I've mapped a lot of are the undeveloped recreation areas owned by New York City to protect its water supply. The city bought them to protect them from development, and allows public access (in some cases requiring that the user apply for a free permit, in others, "come one, come all!") I've tagged these with boundary=protected_area protect_class=12 protection_object=water, and then added leisure=nature_reserve as a rendering stopgap (because class 12 doesn't render either). One reason that I disfavour 'leisure=park' is, simply, the renderer. (I know, don't tag for the renderer!) The objects that render with borders (nature_reserve, national_park, protected_area for classes 1-6) don't obscure landcover, so those who wish to map landcover in these large areas can do so without collision. The only place where I've really tried to do that has been Bear Mountain - where I was producing a detailed map for a group outing a couple of years ago. I didn't push beyond the specific area that I needed. https://www.openstreetmap.org/relation/6467468 The huge protect_class=2 areas in New York tend to turn into unreadable messes with this scheme, but they'd turn into unreadable messes with *any* scheme. The land management is simply that complicated. The area around https://www.openstreetmap.org/relation/6442393#map=10/44.0624/-73.9723 is simply a patchwork, and nothing will make it pretty. _______________________________________________ Talk-us mailing list Talk-us@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-us
