- From: Doug Turner <doug.turner@gmail.com>
- Date: Tue, 11 Nov 2008 15:40:58 -0800
- To: Richard Barnes <rbarnes@bbn.com>
- Cc: Andrei Popescu <andreip@google.com>, "Thomson, Martin" <Martin.Thomson@andrew.com>, Greg Bolsinga <bolsinga@apple.com>, public-geolocation <public-geolocation@w3.org>
Hi RIchard, I think you missed my point. On the web, you want a required universal data type for gelocation as basis. Fragmentation will arise if you don't have this. Doug On Nov 11, 2008, at 3:17 PM, Richard Barnes wrote: > Doug, > > We should remember the distinction between "mandatory to implement" > and "mandatory to use"; what we're talking about here is the > former. All the API does is define a data structure, which is how a > web page gets data *if* the browser provides it. Adding a field to > the API entails no cost for implementers that don't want to use it > -- either on the location provider end or the consumer end. > Providers don't have to fill the field if they don't want to, and > web pages don't have to look at it. A location provider that > wants to do reverse geocoding *can*, but it certainly wouldn't have > to. > > By way analogy: Just because there are lat/long fields doesn't mean > a UA has to have GPS. In the same way, just because there are civic > fields doesn't mean a UA has to do reverse geocoding. In fact, > neither case makes any requirement of the UA except to create an > object that's either null or has a particular structure. > > On the other hand, if you enable location provider to provide civic > location, you enable a whole other class of location based > applications (ones that prefer civic addresses, e.g., postage rate > calculators, to pick a random example), and location providers (ones > that can only return civic addresses, like the IETF network I > described earlier). > > --Richard > > > Doug Turner wrote: >> Richard, >> We also have to worry about adoption. We want interop between all >> UAs and the web. There is a significant cost to reverse >> geolcoation and/or Civic addresses. For example, the base >> implementation of a UA and a GPS device has no understand of how to >> translate the location data from lat/lon to anything greater. My >> concern is that if we push ahead and provide a civic address as a >> non-optional part of the Position element, you will effectively cut >> off the base UAs from participation in the geolocation enabled web. >> For this reason, we pushed any non-lat-lon-location data until v.2 >> Doug >> On Nov 11, 2008, at 1:09 PM, Richard Barnes wrote: >>> Andrei, >>> >>> Discussion of how you populate a civic address field is completely >>> separate from the format of the field itself. Just because we've >>> got a lat/long in the current version doesn't mean we have to say >>> how a location provider uses GPS, right? The point of this API is >>> just to provide access to whatever location is there, not to >>> specify how to get it. How the location gets there (into the >>> browser) is up to the location provider. >>> >>> If you're curious though, by and large civic location has to be >>> manually configured or reverse-geocoded. The IETF networks at the >>> last few IETF meetings have been location-enabled, and we've >>> provided civic addresses (down to an individual room) >>> corresponding to the 802.11 AP that a client is connected to. >>> This is a good example of a case where civic is a lot easier to >>> use that geodetic -- it would have been a huge pain to set up any >>> sort of geodetic positions for APs. >>> >>> As far as the syntax I was suggesting, I was imagining a compound >>> position object, for example: >>> interface Position { >>> readonly attribute Geodetic geodetic; >>> readonly attribute Civic civic; >>> readonly attribuet UsageRules rules >>> } >>> (This is what a Position looks like in the current HELD location >>> provider.) A client would then get civic information like I >>> showed before, geodetic information with something like >>> "loc.geodetic.latitude", rules with something like >>> "loc.rules.retransmissionAllowed". >>> >>> Cheers, >>> --Richard >>> >>> >>> Andrei Popescu wrote: >>>> On Tue, Nov 11, 2008 at 6:40 PM, Richard Barnes <rbarnes@bbn.com> >>>> wrote: >>>>> I though the group had discussed "reverse geocoding", which, I >>>>> admit, is >>>>> more complicated. This is just defining a format. >>>> I'm not sure why we'd define a new interface (i.e. 'Civic') if >>>> there >>>> is no way to produce objects that implement it. Or if we do >>>> specify a >>>> way to produce such objects (e.g. your example suggests adding a >>>> 'civic' attribute to the Position interface) then I don't see how >>>> we'd >>>> be able to completely separate the discussion from reverse >>>> geocoding. >>>> I think the two should be discussed at the same time. >>>> Andrei
Received on Tuesday, 11 November 2008 23:41:38 UTC