Subject: [Geopriv] Question on draft-linsner-geopriv-relativeloc-01

From: [email-masked]
Date: Fri, 6 Jul 2007 15:16:07 -0400

Hi Marc, list, 

First, I find this draft to be marginally useful.  There will be some 
cases where such relative offsets are helpful, but I expect not too many. 

That said, I have a comment/question on Z dimmension.  Sec 4 sez: 
        "If the altitude (Z) parameter is expressed, it is assumed to 
   utilize locally significant ground level (the ground directly below 
   the relative location) as the reference point from which to measure."

So, is this intended to mean Z is measured relative to the reference point 
taken as Z=0, or actual ground level (ie. "dirt") below the X-Y offset 
point.  Both interpretations seem possible, but it seems to say more the 
latter. 

I would think the latter would be quite confusing to try to use in 
practice (how to know whether the actual ground level slopes below the 
building the user is in, how many meters to account for each floor etc). 

But, the former interpretation seems much more intuitive, since it would 
normally be relative to whatever surface the user is actually standing on 
when standing at the reference point (e.g. Z = 2 would be 2 meters above 
floor level, on whatever floor the rest of civic location gave you). Also, 
since both X and Y offsets are relative to the reference point (0,0) it 
would be consistent for Z to also be relative to that reference point (ie. 
reference point is 0,0,0). 

What's the intent, why? 

( Also a tiny nit I spotted in sec 1, para 4, should read " ... address 
SHOULD NOT be allowed ..." .  )

-- Peter
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From: "Marc Linsner" <[email-masked]>
Date: Sat, 21 Jul 2007 16:34:59 -0400

Rohan,

> 
> My question is if this is free text or machine readable encoding?
> 

Machine readable encoding of local significance.

-Marc-