[Xastir] Datum conversions

[James Ewen]

Okay, now you get to drag me around another learning curve.
 
I got ahold of a bunch of shapefiles for an area where we will be using APRS
to track assets for an upcoming cross-country ski race in February.
 
I stuffed them into my map directory, and found that I could not see them.
After a little head scratching, I finally figured out that the datum might
be wrong. shpinfo show me file bounds of 1369668.166, 923382.659 /
1386313.311, 934944.981
 
I would guess that this might be UTM values, but don't know how to determine
that for sure.
 
Reading Tom's tutorial, it looks like I have to be able to tell the
conversion program what datum it starts in, and what datum I'd like it to
end up in.
 
I would guess that there's no info encoded into the file to determine what
datum is used, otherwise the conversion program would only need to know the
desired output format.
 
The area in question is at about 53.5N, 112.8W.
 
Another thing I'd like to know, once I get the shapefiles working, is
whether there is a was to convert a shapefile to a gps track. I have a
shapefile theme that is the trace of the course to be skied. If I could turn
that into a GPS track, and upload it to my Garmin GPS II+, I could use the
trackback simulator to create a pseudo-lead skier.
 
It's a little tough to run a lead vehicle in front of the leader of this
race. Nothing is allowed on the course before the skiers. A snowmobile would
destroy the tracks that are set for the skiers, and would cause a great deal
of problems. The only way to track the lead skier is to give them a tracker
to carry, or to run a simulated tracker along the course.
 
James
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