Hi.  It appears that in initialization, if an airport and heading are
specified on the command line, a runway is immediately chosen based
upon the heading, and latitude/longitude is set to that runway's
threshhold.  This is sensible if the user is starting *at* the airport;
but if the user is starting somewhere else, and using the airport
as a reference point via --offset-azimuth and --offset-distance,
the result is that starting position can jump by a large amount
simply by changing the starting heading.  Changing the heading
changes the runway fg_init thinks is relevant, and the offset is
taken from the position that's been set to an irrelevant runway
threshold location.

I ran into this tonight while trying to contrive some aliases for
quickly starting FlightGear with the ufo at a specific vantage
point near a structure I'm modelling.  I decided I wanted to be on
the other side of the structure, so I added a couple of degrees to
my --offset-azimuth value, and changed my heading by 90 degrees.
Upon restart, I didn't see the structure.  I spent quite a while
trying to determine why it wasn't loading before I realized that
it *was* loading, and that the reason I didn't see it was because
I was a kilometer and a half away from where I thought.

Not very important at all -- it probably takes a fairly contrived
situation (like mine) to get bit by this -- but figured I'd
mention it.


Chris Metzler                   [EMAIL PROTECTED]
                (remove "snip-me." to email)

"As a child I understood how to give; I have forgotten this grace since I
have become civilized." - Chief Luther Standing Bear

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