Future of location services on OM

Gergely Imreh imrehg at gmail.com
Sat Jan 10 05:42:58 CET 2009


Hi,

  I was wondering if there's any plan, what kind of gps positioning /
location discovery services the OM should have or will have?
  Right now, as much as I see there are a number of ways: the 2008.x
releases have gpsd, the FSO has gypsy, and Android - I don't know
whether the GPS services work on that one yet.

  The problem with this is that it's hard to develop for this variety
of options that are not compatible. The IMHO best would be a d-bus
interaction with the userspace software, because it will put the
burden of interpreting the NMEA  (and possible other) messages on the
LocationProvider, so the userspace software does not have to duplicate
the functionality (less possible points of failure).
  Now, gpsd says it has dbus interface, just one has to check the
source code and it is not finalized. Is the gpsd included in the
2008.x compiled with the dbus option? Probably most people only use
TangoGPS or Navit, which interprets the NMEA messages themselves, so
they didn't see the need for any other interface option. Also, gpsd
has been tested, and seems to be reasonably reliable.
  Gypsy was working generally alright, and could use it, but sometimes
it had weird behaviour - maybe just not what I'd expect but otherwise
fine.

  Also, the last gpsd release was was 11 months ago, though there
seems to be some SVN activity[1]. The last Gypsy release was about 10
months ago, last Git activity ~8 months ago, so not sure how much is
that one alive...

  When checked Android, they have a few interesting features in the
positioning area. I think they have their own GPS hardware interfacing
and interpretation, which is then supplied to the userspace. Also,
they have a number of different location providers, like the gps
satellites, GSM cell information, Wifi hotspots.... [3]
  Previously, a few of us tried to make a fast positioning app based
on GSM cell info [4-5], but we had to map the cell tower positions
ourselves (pretty imprecise) and do the position discovery algorithm
(I think I borked that a bit, sometimes it was good, by chance, most
of the time it was very off).  Andorid uses Google's on cell database,
but I'll check it out, whether we too would be able to / allowed to
use that info. Will try to learn from them, not to clone, but to make
less mistakes.

  I was thinking, what route you think would be more advantageous for OM?
  Gpsd / gypsy / multi-provider Android-type / other? There might not
be a single preferred way, and you might say that it's not the core
teams responsibility. In any case, I'd be interested in your opinion.
(I hope I'm not replicating a previous discussion either :)

  Cheers,
      Greg




[1] http://svn.berlios.de/viewcvs/gpsd/
[2] git://anongit.freedesktop.org/git/gypsy
[3] http://android.git.kernel.org/?p=platform/frameworks/base.git;a=tree;hb=HEAD
 ("location" folder)
[4] http://projects.openmoko.org/projects/rocinante/
[5] http://repo.or.cz/w/CellLocator.git



More information about the devel mailing list