location providers

hello.

i am still not quite sure where to look up open issues, could somebody 
please point me to the right place?

a while ago i raised two questions about altitude, one was about the 
model of altitude (WGS vs. EGM), and the other was about GPS vs. 
barometric altitude. then we had the more general remark about the fact 
that there can be various location providers, and in fact both of the 
above issues could be summarized under that more general topic (even 
though WGS vs. EGM also could be regarded as a simple unit issue; but 
alas one that requires decidedly non-trivial conversions).

the comments on that list mostly seemed to argue that having multiple 
location providers (such as multiple altitude values, or even multiple 
locations) would complicate the API. and i guess there is no denying 
that this would be the case. however, i am still curious to hear from 
the proponents of the "there can only be one" (location) approach how 
they assume implementers of the APIs would deal with the problem of 
having to decide on for example "the altitude", when the device has two 
conflicting readings from GPS and barometric sensors.

it seems to me that having only one location is a simplification that 
either can take place in the API's implementation, or in the code using 
the API. there are advantages and disadvantages to both approaches. API 
simplicity is definitely an advantage of doing the simplification in the 
API's implementation, and i am still curious to hear how the API's 
implementation is supposed to do this.

cheers,

erik wilde   tel:+1-510-6432253 - fax:+1-510-6425814
        dret@berkeley.edu  -  http://dret.net/netdret
        UC Berkeley - School of Information (ISchool)

Received on Wednesday, 21 January 2009 17:23:28 UTC