>Thanks James, that's pretty much what I've been proposing.
I know we aren't too far apart but what I am proosing is not what you
have been proposing - as I don't agree with your proposal to include both
USA->Florida->Miami->BuildingA->Floor4
and
USA -> Florida -> Miami -> Building A -> Floor 4 ->
Elevator -> Polygon Offset
in the same message. I am personally in favor of just having any one
<element> in the PIDF-LO once, such as this:
> > Civic: USA->Florida->Miami->BuildingA->Floor4
> > Relative: (ref-point=) <some point on 4th floor>->offset from that point
but I know Brian is the one who adamantly opposes the idea of
indicating which is the reference point/element - and I think that is
flawed. I believe my offering above is the one that interoperates
perfectly with existing implementations, given that any LR that
doesn't understand this particular extension can't confuse any of its
ref-point= or offset elements (in XML or in binary).
We also can't expect that an LR that does understand this extension
to somehow not understand the <ref-point=> element, so that argument
goes out the window in this proposal.
The key to the above proposal is to uniquely identify each "Relative"
<element>. You can call this another location type, you can call this
variations of the <INT> element type. I don't care as a practical
matter, just so long as they are uniquely identified so any LR that
doesn't understand this extension CAN'T misinterpret the information
(which is a fear you've stated over and over again).
There also needs to be MUST NOT level text about not allowing the
offset to be very far away from the perimeter of the property that is
understood within RFCs 4119 and 5139. If we agree on that idea, we
can then work on the distance that should be allowed, and what is too
far - as guidance. An example of this in urban areas is nothing
outside the parking lot perimeter surrounding the building in the
PIDF-LO. I'm not sure what is viable in rural areas, but perhaps the
property line in the PIDF-LO is good there too.
James
>
> > I think it should like this:
> >
> > Civic: USA->Florida->Miami->BuildingA->Floor4
> > Relative: (ref=) Elevator->offset
> >
> > where the reference <element> is identified, and everything in the
> > relative part is separately indicated to ensure there is no confusion.
> >
> > This both reduces the data to its minimum set, and for
> > interoperability - only what's understood will be used, with the
> > possibility that the recipient doesn't understand this extension,
> > meaning they don't understand the whole "Relative" part, leaving that
> > entity to believe the target is on <Floor>4</Floor>. We just have to
> > have firm text saying the target must be within x distance of floor
> > 4. An easy example of somewhere outside floor 4 that still needs to
> > be valid is a parking lot outside the building, or a window cleaner
> > hanging outside the windows of floor 4.
> >
> > James
> >
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