Bugs in decoding of lat, lon from database files

[John Peterson <jaypee netcom com>]

Hi Everybody,

   (I think it's still just Michael and myself, but welcome to anyone
else who has since joined). Well, I'm not just treatening to get back to
work on fplan, I really am this time! Things have been busy at work,
but have finnaly calmed down considerably, and now the work related to
setting up "linux-aviation" is finally behind me too.

   Anyhow, just a quick note. An intrepid user from India has discovered
that the functions in db.c that decode the lat, lon (and magnetic var
too), don't work as advertised for deg < 0 (E longitudes, S latitudes,
and E variations respectively). The problem is that the sign is not
extended to the minutes field as the documentation claims.

   I will be working with db.c for the next few days. I thought I had a
quick fix, then I discovered it's a little trickier than I first
thought. (The example that broke it was something like -0 degrees, and
30 minutes. If you just let the input conversion handle the sign, you
"lose it" for the case of zero degrees). The magnetic variation
conversions were also affected, curious I didn't notice the problem
before. Oh well...

   I've also been thinking of fixing the "international date line"
problem in the preview code.  I think this can be fixed by introducing
another coordinate system "on top" of the usual -180 to +180 system
actually used for storing longitudes.  This new plot coordinate system
is either -180 to +180 as is used now, or +0 to +360 for plans that
span the +/- 180 region. (This would restrict plans to not span any
more than 90 degrees of longitude I guess). Any further thoughts?

Later, John

-- 
 ___|___  | John C. Peterson, KD6EKQ | How many times would you like to
  -(*)-   | mailto:jaypee@netcom.com | reboot Microsoft Windows today?
  o/ \o   | San Diego, CA   U.S.A    | See http://www.linux.org/ for info