[Geojson] [georss] simple 3D geocode for AR

Carl Reed creed at opengeospatial.org
Thu Aug 27 17:05:43 PDT 2009


Mike -

Interesting questions.

What is simple? There is an interesting quote by the mathematician 
Whitehead, "Seek simplicity but distrust it."

Interesting quote :-) especially given recent stories about folks using GPS 
and getting themselves into interesting situations with legal and liability 
issues.

Anyway, I will get off of my soapbox.

As to WGS 84 being explicit, as long as the supporting documentation is VERY 
clear about what is meant by WGS-84, e.g. 2d, 3d, projected, geodetic, 
geographic. I would suggest an explicit reference to the EPSG registry for 
code 4979 (3d geographic). I would also suggest checking out some IETF 
standards that deal with "simple" expressions for locations (ones I am 
familiar with), such as for DHCP ([RFC 3825] "Dynamic Host Configuration 
Protocol Option for Coordinate-based Location Configuration Information" and 
internet draft "A Uniform Resource Identifier for Geographic Locations 
('geo' URI)"

One of the issues we have been dealing with in all of these location 
protocols and encodings in the IETF, NENA and the OGC is the issue 
uncertainty. Without some expression of uncertainty, then how does one 
access the quality/value/appropriate usage for the coordinate(s)? And of 
course then there are the related legal and liability issues.

Hence, the above quote!

Regards

Carl



----- Original Message ----- 
From: "Mike Liebhold" <mnl at well.com>
To: <geowanking at geowanking.org>; <georss at lists.eogeo.org>; 
<geojson at geojson.org>; "Gene Becker" <gbecker8888 at gmail.com>
Sent: Thursday, August 27, 2009 5:35 PM
Subject: [georss] simple 3D geocode for AR


>A friend wrote me with a request for clarification on a topic we've
> discussed many times here,  but every time we've approached a consensus
> the answer seems elusive.
>
> Many devleopers are starting to create applications for iPhones and
> Android phones to view location specific data  through the viewfinder
> using the -imprecise- capabilities of the built in gps and compass and
> applications platforms like Layar.
>
> The question:
>
> What is the -simplest- way to geocode a geoannotation in 3D using
> geoRSS/Atom, geojson, KML ....?
>
> (Is there a practical reason why WGS '84 shouldn't be implicit, and a
> CRS  lookup NOT be required?)
>
>
> _______________________________________________
> georss mailing list
> georss at lists.eogeo.org
> http://lists.eogeo.org/mailman/listinfo/georss 




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