[GRASSLIST:9934] Re: GPS Tracklog points to lines (GPS Babel)

[Hamish]

re. v.in.garmin loading track-as-point but not track-as-line

Dave:
> 2. I used what was in grass6.0 and 6.0.1 and then downloaded a CVS 
> version from a mailing archived in the list May 2005. All gave the
> same results

Please get the lastest 6.1 CVS snapshot version and try with it. There
have been 9 revisions to the module since last May. Here is the link to
it from online CVS interface:
http://freegis.org/cgi-bin/viewcvs.cgi/*checkout*/grass6/scripts/v.in.garmin/v.in.garmin?rev=HEAD&content-type=text/plain


Dylan:
> >> I, and many others on this list have had similar problems.
> >>
> >> I know that it is possible to get tracklog _lines_ imported into
> >> GRASS via v.in.garmin , but it seemed like that functionality was
> >> broken sometime in the last 7 months or so.

me:
> > I wasn't aware the problems were that widespread. Could be I am
> > using a Debian awk extension that isn't standard across distros??

I have now tested the latest CVS version on Debian/stable (sarge) and 
Redhat 9. It works fine for me on both.


Dave:
> 5. You need a field assistant that knows GRASS (apart from the
> GPS interface apparently)? I'm for hire and have wheels.

You'd need wings or gills... I'm in the south pacific. :)


> 7. GPS is native rs232 but I have had the same successes and
> challenges through a Prolific serial2usb convertor ("iconcepts"
> pl232). Laptop has no serial.

gpstrans is known to have problems over USB. But as you've been able to
get point data through, gpstrans is most likely working for you and the
problem is possibly in the awk or cs2cs processing steps?


> 8. Another GRASS head (Scott Mitchell) was helping out with 
> troubleshooting and some thoughts on changes to how GRASS imports
> ASCII came up when the ASCII module started screaming. This would
> happen when we did not force conversion to points.

Need to see the exact error messages to diagnose. But update to the 
latest CVS version first.


> 9. The same problem existed in the lab (Fedora core) and my home
> machine (Gentoo).

Again, v.in.garmin works fine for me when I test it on Debian/sarge & 
Redhat 9. So maybe the trouble lies elsewhere.

does this work?

gpstrans -p/dev/gps -i 


> I've seen reference to awk scripts to change points to lines, but
> alwasy looked hack and slash (mainly cause I don't know awk).

Ascii import as a line with 'v.in.ascii -n format=standard' is fairly
simple, only annoying bit is you need to calculate how many vertices in
each line before you present the data.

hint: steal the awk commands from the v.in.garmin script.


> 10. if this lab goes well we might play with some insitu stuff.
..
> Let me know if your gpsd becomes part of grass.

No, my client for gpsd is just a datalogging routine, not much to do
with a GIS. If you want one, I recommend the gpxlogger program that
comes with gpsd 2.30.
  http://gpsd.berlios.de/

I had written a m.realtime_gps module using gpsd to do real time GPS
plotting into GRASS 5, but the display driver really isn't made for that
sort of thing. I have mostly abandoned it in favour of gpsdrive with 
backdrop maps created with the GRASS 6.1cvs d.out.gpsdrive module.
  http://www.gpsdrive.cc/
  http://grass.ibiblio.org/grass61/manuals/html61_user/d.out.gpsdrive.html


> 11. I'm using Garmin Etrex Vista. I imagine the garmin protocol has
> not changed.

Someone here has an etrex, I'll try and get hold of it to test. I have
no idea what garmin has done or not done to their protocol. You can 
test it in linux using the gpsman or gpsbabel Garmin interface.


> I am looking to enslave a Garmin RINO with a home made cable to do
> some  post processing corrections. perhaps your GPSD might be useful.

Gpsd isn't mine, I just wrote a simple client for it. See above link.
It's nice.


me:
> > can you run gpstrans by itself and send me the -dt track file so I
> > can test your data?

?

> >And a copy of what is written to the console (use -v verbose mode)
> >when you attempt to load a track?

?


Hamish