- From: Raj Singh <rsingh@opengeospatial.org>
- Date: Mon, 13 Jun 2011 16:50:19 -0400
- To: Thomas Wrobel <darkflame@gmail.com>
- Cc: Jens de Smit <jens@layar.com>, public-poiwg@w3.org
I think we still do have the requirement that each POI specifies its own CRS with a default of WGS84. Some of your points refer to moving objects, which I think we have agreed are a slightly different type of POI than we will fully describe in the Core. So that we do a better job of sticking to Core discussion and finishing that -- while not losing the voices around the extensions of interest -- I've created a wiki page to capture this information: http://www.w3.org/2010/POI/wiki/Extensions --- Raj The OGC: Making location count... http://www.opengeospatial.org/contact On Jun 12, at 2:03 PM, Thomas Wrobel wrote: > Depending on accuracy, calculating between lat/lon and meters can be > massively, massively, complex. You get into such factors as the real > shape of the earth - its not a simple bit of trig sadly. > Of course these are all "solved problems", but if possible its nice if > a client doesn't have to do them. (or, rather, as little as possible - > working out a position in meters for lat/long, then displacements from > that is less cpu then working out a large batch of conversions). > Neither is insurmountable, however. > > From my perspective the most usefull scenario for relative > co-ordinates is simply with stuff that can move - it would be nice if > only one gps location change has to be passed to the client, rather > then everything attached as well. > > I'm also still favouring the idea that each POI should specify its own > reference system ( WGS84 default), and if it links to another POI > ("relative too" or something), then it positions its own reference > system (if not WGS84) relative to that one. This should make any > inter-POI positioning no more verbose then anything else. > This wouldn't solve multiple co-ordinate systems within the same > POI....but I'm not sure how much that will be used in the AR Field. > > -Thomas > > On 10 June 2011 17:26, Raj Singh <rsingh@opengeospatial.org> wrote: >> Jens, I think you probably mean to support both point formats, and only use the GeoRSS GML format (more brevity) for lines and polygons? I can live with that. >> >> --- >> Raj >> The OGC: Making location count... >> http://www.opengeospatial.org/contact >> >> >> On Jun 10, at 9:58 AM, Jens de Smit wrote: >> >>> I've heard (on the list and on the call yesterday) arguments for both >>> the short, space separated form and the long, individual key form. >>> Brevity and conformance to GML/GeoRSS are arguments for the short >>> form, ease of lookups/XSLT and explicit naming of lat/lon/alt for the >>> latter. >>> >>> Saying "let's use both" obviously places the burden on the >>> implementors... but I think this is still manageable, so I'd like to >>> see both. >> >> >>
Received on Monday, 13 June 2011 20:50:54 UTC