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Re: POI Core strawman: encoding geography + namespaces/serialisation format

From: Raj Singh <rsingh@opengeospatial.org>
Date: Wed, 4 May 2011 23:36:20 -0400
Cc: "public-poiwg@w3.org" <public-poiwg@w3.org>
Message-Id: <66E2A542-BB74-4264-91AC-2E0272A4806F@opengeospatial.org>
To: roBman@mob-labs.com
Even though I suggested it, I'm actually against namespaces also, as I recently blogged about [1]. The pros and cons of namespaces is better left to a teleconference than an email discussion, but bottom line is that I think they do more harm than good, and I wouldn't mind dropping them. 

[1] http://www.rajsingh.org/2010/10/namespaces-ruin-xml/

---
Raj
The OGC: Making location count...
http://www.opengeospatial.org/contact


On May 4, at 6:43 PM, Rob Manson wrote:

> This raises the question about serialisation format though.
> 
> If we're using these types of external namespaces (e.g. gml: atom: etc.
> - which I think is a good idea to support) then this is almost
> exclusively XML (at the moment).
> 
> JSON does not in general support namespaces and many people seem opposed
> to this concept. Although, geojson had a go at it with @namespaces [1]
> but this doesn't seem to be actually specified anywhere.  And there's
> been a bit of debate and a few proposals that got shouted down on the
> JSON Schema list, etc.
> 
> If we go with the simple model outlined in the wiki link [1] then we
> could benefit from all these existing namespaces/data models and have a
> relatively consistent model across both XML and JSON...along with making
> it more extensible.
> 
> 
> roBman
> 
> 
> [1] http://wiki.geojson.org/GeoJSON_draft_version_6#Including_additional_members
> 
> 
> On Wed, 2011-05-04 at 14:21 -0400, Raj Singh wrote:
>> Here are notes on modifying geometry to harmonize with the W3C Geospatial Vocabulary report [1] and GeoRSS [2]
>> 
>> [1] http://www.w3.org/2005/Incubator/geo/XGR-geo-20071023/
>> [2] http://www.georss.org/gml
>> 
>> There's more specifying to do here, put I've put some examples below.
>> 
>> CHANGE:
>> <point latitude="42.360890561289295" longitude="-71.09139204025269"/>
>> TO:
>> <gml:Point><gml:pos>42.360890561289295 -71.09139204025269</gml:pos></gml:Point>
>> 
>> CHANGE:
>> <point id="mainpoint" latitude="27.174799" longitude="78.042111" altitude="10m"/>
>> TO:
>> <gml:Point id="mainpoint" srsName="urn:ogc:def:crs:EPSG:6.6:4979" srsDimension="3">
>> 	<gml:pos>27.174799 78.042111 10</gml:pos>
>> </gml:Point>
>> 
>> reference: http://www.georss.org/gml
>> "If your GeoRSS GML data is in a coordinate reference system other than lat/lon WGS84 (often technically referred to as EPSG:4236), add in an srsName attribute to your geometry. 3D decimal degrees CRS example The key thing here is to use CRS epsg:4979, specify the srsDimension attribute, and include a third number in your coordinate tuple."
>> 
>> 
>> CHANGE:
>> <route>
>> 	<point order="0" latitude="42.360890561289295" longitude="-71.09139204025269"/>
>> 	<point order="1" latitude="42.361176" longitude="-71.09018"/>
>> 	<point order="2" latitude="42.36272976137689" longitude="-71.09049081802368"/>
>> 	<point order="3" latitude="42.36318955298668" longitude="-71.09677791595459"/>
>> 	<point order="4" latitude="42.363617631805496" longitude="-71.10156297683716"/>
>> </route>
>> 
>> TO:
>> <gml:LineString>
>> 	<gml:posList>
>> 		42.360890561289295 -71.09139204025269 42.361176 -71.09018 42.36272976137689 -71.09049081802368 ...
>> 	</gml:posList>
>> </gml:LineString>
>> 
>> CHANGE:
>> <area>
>> 	<point order="0" latitude="42.360890561289295" longitude="-71.09139204025269"/>
>> 	<point order="1" latitude="42.361176" longitude="-71.09018"/>
>> 	<point order="2" latitude="42.36272976137689" longitude="-71.09049081802368"/>
>> 	<point order="3" latitude="42.36318955298668" longitude="-71.09677791595459"/>
>> 	<point order="4" latitude="42.363617631805496" longitude="-71.10156297683716"/>
>> 	<point order="5" latitude="42.360890561289295" longitude="-71.09139204025269"/>
>> </area>
>> 			
>> TO:
>> <gml:Polygon>
>> 	<gml:exterior><gml:LinearRing>
>> 		42.360890561289295 -71.09139204025269 42.361176 -71.09018 42.36272976137689 -71.09049081802368 ...
>> 	</gml:LinearRing></gml:exterior>
>> </gml:Polygon>
>> 
>> 
>> 
>> ---
>> Raj
>> The OGC: Making location count...
>> http://www.opengeospatial.org/contact
>> 
>> 
>> 
>> 
> 
> 
Received on Thursday, 5 May 2011 03:36:45 GMT

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