[Tagging] Feature Proposal – RFC – natural=peninsula (Was: Feature Proposal – RFC – place=peninsula)

[Kevin Kenny]

On Fri, Jan 18, 2019 at 2:49 PM Markus <selfishseahorse at gmail.com> wrote:
> Regarding areas with fuzzy boundaries, i could imagine a new kind of
> relation that contains one multipolygon relation for the part of area
> that certainly belongs to the area feature ('minimal area') and one
> multipolygon relation for the fuzzy area (= 'maximal area' - 'minimal
> area'). However, this is not part of this proposal.

We deal with indefinite objects more often than some people are
comfortable with. (I've mentioned previously that my state has such
things as county lines that are in part unsurveyed!)

Rather than a new relation type, I think it would be simpler to tag
the indefinite part of the boundary of whatever area feature with a
key like "indefinite=yes". An indefinite boundary will normally have
no reason to have tags of its own other than this one - because it
would need to be a 'real' feature in order to have most of them be
meaningful. It would ordinarily be there only to close a multipolygon
topologically, and the tags of the multipolygon of which it's an inner
or outer way would ordinarily be the only other information pertaining
to it.

If we try to fix "maximal" and "minimal" area, we'll simply run into
more haggling- because the maximum and minimum do not have bright-line
definitions, any more than the indefinite line does. We'll have
interminable arguments over what land might and might not be
considered part of a peninsula. I'd like to nip that in the bud by
simply declaring that any choice is arbitrary, and that the drawing of
an arbitrary boundary of an area feature should be informed in part by
what the locals think. Is Wareham, Massachusetts on Cape Cod? I have
no idea, but I bet that the locals have a rough consensus - and if
they don't, that they'd at least be unsurprised if a mapper were to
choose the Cape Cod Canal or the Plymouth County line as the cutoff
with an 'indefinite' indication.

Simply having the tagging allow for an 'indefinite line', I think,
could be a near-universal solution to the fact that bays, peninsulas,
channels, isthmuses, lakes with broad inlets/outlets, rivers with
broad mouths, administrative regions with unsurveyed boundaries,
mountain ranges,  etc. all are area features that have a distinct
shape, except for the fact that part of their margin may be
indefinite.

Try as we might to make them go away, there are objects, observable
and named in the real world, that are areas, part of whose boundaries
are indefinite. Saying that such things can be only point features is
shortsighted.

I support the 'peninsula' proposal, with the caveat that the Wiki
should indicate that large (we need guidance on just how large)
peninsulas should not yet be mapped, because of the technical problems
in enormous relations. If Arabia, Malaya, Kamchatka, Gaspé  or
Delmarva are likely to choke the servers, then we need at least
temporarily to exclude them - just as we exclude the Gulf of Bothnia
or the Sea of Cortez. I'm certainly willing to concede that the
technical limitation needs to be respected - without ruling out the
idea that someday it may be relaxed or eliminated.