[GRASSLIST:3314] GPS - Raster overlay

[Paul Wefel]

Hi, 

I am relatively new to the world of GIS and escpecially GRASS.  What I am
trying to do is to plot a track from my Garmin GPS and then plot specific
points on top of that track.  Then I would like to overlay that data ontop of
a digital orthophoto quarter quad.

I have written the necessary Perl glue to convert the GPS data so that
s.in.ascii will import it.  I created a location in grass5 using lat-long and
set the boundaries to be equal to the lat-long boundaries of my DOQ.  I then
used d.sites to display my track data and point data.  This worked well.

Next I opened the MrSid formatted DOQ in a MrSid viewer and saved it as a
GeoTiff file.  I then tried to import the geotiff into my lat-long region
using both r.in.tiff and r.in.gdal but kept getting errors about north lat
out of range.

I did some searching on the lists and found a suggestion to import the
geotiff into a new location defined as x-y and set to equal the resolution
of the geotiff,  I did this and was able to import the file and display it
with d.rast.  Now I am trying to move either the lat-long sites data into
the x-y location or move the x-y raster into the lat-long location. 

Any suggestions on how I can get the lat-long data to overlay the DOQ?

Thanks, 

-paul

-- 
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|Paul Wefel            NCSA                 Network Engineer    |
|phone: 217-244-2193   cell: 217-840-9929   pwefel at ncsa.uiuc.edu|
|CAB 269, 605 E Springfield, Champaign IL 61820                 |
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