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

Tue Sep 1 08:48:49 PDT 2009

Mike et. al.

Since URIs are mentioned, perhaps you might want to check out a document I 
have been helping with:  A Uniform Resource Identifier for Geographic 
Locations. The URL to this document is: 
http://tools.ietf.org/id/draft-ietf-geopriv-geo-uri-02.txt

This document is well on its way to becoming an internet RFC (standard)

Regards

Carl

----- Original Message ----- 
From: "Mike Liebhold" <mnl at well.com>
To: "Chris Goad" <chris at platial.com>
Cc: "Christian Willmes" <c.willmes at uni-koeln.de>; "geojson" 
<geojson at lists.geojson.org>; <geowanking at geowanking.org>; "GeoRSS" 
<georss at lists.eogeo.org>
Sent: Monday, August 31, 2009 6:55 PM
Subject: Re: [georss] [Geowanking] [Geojson] simple 3D geocode for AR

> Mike Liebhold wrote:
>>  wondering if the location semantics in the URI could be as plain
>> language simple
> also wondering, how much about rendering, viewing, and pov should be
> included in a uri.
>
> probably none.
>
>>
>> ?
>>
>> Chris Goad wrote:
>>> There is a substantive issue here to do with local coordinate
>>> systems.  When representing the features of a particular object it is
>>> sometimes useful to employ coordinates local to that object, and
>>> represent separately the position of the object in the world or
>>> relative to its parent in a heirarchy. Reasons: The  coordinates of
>>> features relative to the object may be known more accurately than
>>> global position of the object, and an AR device's relative position
>>> to the object might also be known with greater precision than its
>>> global position.  The object may not have a fixed position (eg AR on
>>> board a ship). The representation is more compact.
>>>
>>> 3d modeling formalisms support this (and full GML does too), but
>>> GeoRSS, GeoJSON, and KML do not. This is probably an argument for
>>> going to represententations  built for 3d in the first place for AR
>>> applications where local coordinates play a necessary role, but
>>> concievably there is a niche for our lightweight geo standards
>>> extended  by addition of a transformation node.
>>>
>>>
>>> -- Chris
>>>
>>> ----- Original Message ----- From: "Christian Willmes"
>>> <c.willmes at uni-koeln.de>
>>> To: "Mike Liebhold" <mnl at well.com>
>>> Cc: "Ron Lake" <rlake at galdosinc.com>; "geojson"
>>> <geojson at lists.geojson.org>; <geowanking at geowanking.org>; "GeoRSS"
>>> <georss at lists.eogeo.org>
>>> Sent: Friday, August 28, 2009 6:00 PM
>>> Subject: Re: [Geowanking] [georss] [Geojson] simple 3D geocode for AR
>>>
>>>
>>>> Hi,
>>>>
>>>> whats the problem here? Its simple coordiante transformation
>>>> stuff... or do I miss something?!
>>>>
>>>> The device gets the geocoordinates from the web, and computes those
>>>> using its own position and orientation to local camera coordinates....
>>>>
>>>> its that simple... I think. ;-)
>>>>
>>>> regards,
>>>> Christian
>>>>
>>>> Mike Liebhold schrieb:
>>>>> Ron Lake wrote:
>>>>>> The most logical coordinate
>>>>>> system for locating such items is a rectilinear coordinate system
>>>>>> (x-y-z
>>>>>> frame) centered (origin) at the focal point of the camera.
>>>>> What's the use case?
>>>>>
>>>>> In most cases, we probably can assume that the geo-annotations
>>>>> exist independent of the viewpoint; e.g. a viewer should be able to
>>>>> see the note attached to a restaurant from any perspective as they
>>>>> pass on a sidewalk, or drive by.
>>>>>
>>>>> In that case, we need absolute coordinates, not relative to the
>>>>> camera perspective.
>>>>>
>>>>> imho
>>>>>
>>>>> Mike
>>>>>> Cheers
>>>>>>
>>>>>> Ron
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Mike Liebhold [mailto:mnl at well.com] Sent: August 28, 2009
>>>>>> 2:05 PM
>>>>>> To: Ron Lake
>>>>>> Cc: Joshua Lieberman; geowanking at geowanking.org; geojson; GeoRSS
>>>>>> Subject: Re: [georss] [Geojson] simple 3D geocode for AR
>>>>>>
>>>>>> Ron Lake wrote:
>>>>>>> The use of geographic coordinates for [location of things in the
>>>>>>> field
>>>>>> of view relative to the camera] likely does not. [ make sense]
>>>>>>
>>>>>> Ron,
>>>>>>
>>>>>> This is really counter intuitive, Can you explain what you mean?
>>>>>>
>>>>>> - Mike
>>>>>>> -----Original Message-----
>>>>>>> From: georss-bounces at lists.eogeo.org
>>>>>>> [mailto:georss-bounces at lists.eogeo.org] On Behalf Of Joshua
>>>>>>> Lieberman
>>>>>>> Sent: August 28, 2009 11:03 AM
>>>>>>> To: geowanking at geowanking.org
>>>>>>> Cc: geojson; GeoRSS
>>>>>>> Subject: Re: [georss] [Geojson] simple 3D geocode for AR
>>>>>>>
>>>>>>> In both GeoRSS GML and GeoJSON, some explicit CRS needs to be
>>>>>>> specified to use 3-coordinate locations. The simplest one for
>>>>>>> GeoRSS seems to be epsg:4979 ( urn:ogc:def:crs:EPSG:4979 ). It
>>>>>>> would need a slight modification to support the GeoJSON long-lat
>>>>>>> encoding. Otherwise use GeoRSS Simple and the elev property.
>>>>>>>
>>>>>>> e.g.
>>>>>>>
>>>>>>> <georss:elev>346</georss:elev>
>>>>>>> <georss:point>42.3234 -173.234134</georss:point>
>>>>>>>
>>>>>>> Well-known text description of 4979
>>>>>>> (http://spatialreference.org/ref/epsg/4979/ )
>>>>>>> GEOGCS["WGS 84", DATUM["World Geodetic System 1984", SPHEROID["WGS
>>>>>> 84",
>>>>>>> 6378137.0,298.257223563, AUTHORITY["EPSG","7030"]],
>>>>>>> AUTHORITY["EPSG","6326"]], PRIMEM["Greenwich",0.0,
>>>>>>> AUTHORITY["EPSG","8901"]], UNIT["degree",0.017453292519943295],
>>>>>>> AXIS["Geodetic latitude",NORTH], AXIS["Geodetic longitude",EAST],
>>>>>>> AXIS["Ellipsoidal height",UP], AUTHORITY["EPSG","4979"]]
>>>>>>>
>>>>>>> Josh
>>>>>>>
>>>>>>> On Aug 28, 2009, at 1:05 PM, Ron Lake wrote:
>>>>>>>
>>>>>>>> Sorry my example should have been
>>>>>>>>
>>>>>>>> <Point id = "P1" CRS = "http://www.blah.bla/standardCRS.xml">
>>>>>>>> <coordinates>100 200 150</coordinates>
>>>>>>>> </Point>
>>>>>>>>
>>>>>>>> But the argument is the same. Similar encodings can be made in JSON
>>>>>>>> etc.
>>>>>>>>
>>>>>>>> R
>>>>>>>>
>>>>>>>> -----Original Message-----
>>>>>>>> From: georss-bounces at lists.eogeo.org
>>>>>>>> [mailto:georss-bounces at lists.eogeo.org] On Behalf Of Andrew Turner
>>>>>>>> Sent: August 28, 2009 9:57 AM
>>>>>>>> To: geowanking at geowanking.org; GeoRSS; geojson
>>>>>>>> Subject: Re: [georss] [Geojson] simple 3D geocode for AR
>>>>>>>>
>>>>>>>> Simplest?
>>>>>>>>
>>>>>>>> Just include a 3rd coordinate in GeoRSS-Simple point or GeoJSON
>>>>>> point.
>>>>>>>> No, this is not explicitly valid. But you see where that discussion
>>>>>>>> gets us. Long windy roads of elusive semantic talk (arguably
>>>>>> necessary
>>>>>>>> in the lon term, but not simple or useable *now*, which is when
>>>>>> people
>>>>>>>> are building these tools).
>>>>>>>>
>>>>>>>> If we lose interest without achieving a near term concensus,
>>>>>>>> developers will just do arbitrary, different solutions. Give them a
>>>>>>>> simple answer now, even if it makes your
>>>>>>>> strict-validation-only-skin
>>>>>>>> crawl just a little bit. :)
>>>>>>>>
>>>>>>>> So I say just do it, and we'll catch up with documenting it as uses
>>>>>>>> emerge.
>>>>>>>>
>>>>>>>> Also, KML already supports 3D points.
>>>>>>>>
>>>>>>>> Andrew
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> (via mobile)
>>>>>>>>
>>>>>>>> On Aug 27, 2009, at 4:35 PM, Mike Liebhold <mnl at well.com> wrote:
>>>>>>>>
>>>>>>>>> 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?)
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Geojson mailing list
>>>>>>>>> Geojson at lists.geojson.org
>>>>>>>>> http://lists.geojson.org/listinfo.cgi/geojson-geojson.org
>>>>>>>> _______________________________________________
>>>>>>>> georss mailing list
>>>>>>>> georss at lists.eogeo.org
>>>>>>>> http://lists.eogeo.org/mailman/listinfo/georss
>>>>>>>> _______________________________________________
>>>>>>>> georss mailing list
>>>>>>>> georss at lists.eogeo.org
>>>>>>>> http://lists.eogeo.org/mailman/listinfo/georss
>>>>>>> _______________________________________________
>>>>>>> georss mailing list
>>>>>>> georss at lists.eogeo.org
>>>>>>> http://lists.eogeo.org/mailman/listinfo/georss
>>>>>>> _______________________________________________
>>>>>>> georss mailing list
>>>>>>> georss at lists.eogeo.org
>>>>>>> http://lists.eogeo.org/mailman/listinfo/georss
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Geowanking mailing list
>>>>> Geowanking at geowanking.org
>>>>> http://geowanking.org/mailman/listinfo/geowanking_geowanking.org
>>>>
>>>>
>>>> _______________________________________________
>>>> Geowanking mailing list
>>>> Geowanking at geowanking.org
>>>> http://geowanking.org/mailman/listinfo/geowanking_geowanking.org
>>>
>>>
>>
>>
>
> _______________________________________________
> georss mailing list
> georss at lists.eogeo.org
> http://lists.eogeo.org/mailman/listinfo/georss 