[Gdal-dev] UTM to MGRS.

[Curt, WE7U]

On Wed, 30 Mar 2005, Frank Warmerdam wrote:

> Sorry, no OGR does not support MGRS.   It has been several months
> since I did something with MGRS so my memory is a bit foggy on the
> details, but I believe that MGRS coordinates interleave the X and Y
> digits including some non-numeric prefixes to identify a grid square.
> So it is hard to represent MGRS as a "coordinate system definition"
> and a set of x/y points.   For that reason, I don't think it is really practical
> to talk about having OGR support MGRS as a coordinate system.

Huh?  Think of MGRS as UTM but with different letters/numbers in
there.  That's all it is.

I implemented MGRS in a GPL'ed program within the last year or two.
We already had UTM in there, but I had to implement all of the
special zones in the Europe area and north of there that vary
between 3 degrees and 12 degrees, instead of the default 6 degrees
for everywhere else.  That grid turned out to be needed for some
countries' (and NATO's) UTM anyway.  I had to implement UPS as well
at that time (coordinate system used at the poles for UTM/UPS), as
that's also needed for MGRS.

So... MGRS is just like UTM, just a different number representation.

If you're working on a GPL'ed program I can point you to the code
and you can lift it directly.  Generic C code.  If it's a commercial
program, talk to me about it.  I wrote that part so I can license
that portion in other manners as well.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
"Lotto:    A tax on people who are bad at math." -- unknown
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