Jim Wilson wrote:
> Those are from two different iterations.  I was just proving that the
> viewer and model were running on the same data, as it had been
> suggested they were not earlier.  The pairs within a single iteration
> match (this is the same data I posted earlier):

Yes, but even between iterations, the FPU error introduces a random
3mm value to the positions you are using.  It doesn't matter whether
the FDM is right or wrong -- even the tiniest different in input
values will result in a 3mm jitter.  If the FDM says that the position
is different by 4.44E-16 meters (the minimum delta value in a double
for a position value of 1m), the output will randomly get moved up to
3mm.

Also, not offense intended, but you still seem to be missing the core
point: the cockpit is locked down to the aircraft position by
definition.  No change in position, of any magnitude whatsoever,
should produce any detectable change in the cockpit pixels on the
screen.

Consider a FGLyingBastard FDM that gives you random values: if it
moves to the left by 3mm, the cockpit will still be in front of the
viewer.  If it moves to the right by 7m, the cockpit will still be in
front of the viewer.  If it warps to Kuala Lampur, ditto.  The moon?
Yup.  Anywhere in the representable universe you try to put the
aircraft, the cockpit should still be in front of the viewer.  But
it's not (quite), it's jittering around.

Andy

-- 
Andrew J. Ross                NextBus Information Systems
Senior Software Engineer      Emeryville, CA
[EMAIL PROTECTED]              http://www.nextbus.com
"Men go crazy in conflagrations.  They only get better one by one."
 - Sting (misquoted)


_______________________________________________
Flightgear-devel mailing list
[EMAIL PROTECTED]
http://mail.flightgear.org/mailman/listinfo/flightgear-devel

Reply via email to