- 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