Torsten Dreyer:

Torsten Dreyer:

Here is a little patch that changes the behaviour of the VOR CDI and OFF-flag
for indicators like the HSI when getting outside the range of the VOR
station.

Currently, when flying at a distance between the effective_range and twice the
effective_range of a VOR station, the in-range property is computed based on
a random value, causing the OFF Flag and the CDI bar to perform an ugly
jitter.

The attached patch introduces a new property signal-quality-norm which is
computed based on the distance to the station and the range. It is 1.0 when
the distance is less than the range and decreases by 1/x^2 for distances
greater than the range leading to a signal-quality-norm of 0.25 for distances
two times the range, 0.125 for three times the range and so on.
The in-range flag is tied to a signal-quality-norm greater than 0.2 (fixed
squelch).
The CDI and GS needle deflection is multiplied with the signal-quality-norm.

The benefit is:
- Ability to animate the OFF-Flag with a smooth transition.
- CDI and GS needle deflection shows correct values when in range
(signal-quality-norm=1.0) and show some wrong indication when the range is
exceeded
- CDI and GS needle start to move, even when the OFF flag is visible
- No more jitter for flag and needles

See the new SenecaII ki525a hsi as an example at
http://www.t3r.de/fg/navpatch.jpg
The numbers on the image are:
(1) the new property signal-quality-norm
(2) distance exceeds the effective-range by 30%
(3) NAV flag has a rotation animation bound to signal-quality-norm and is
partially visible
(4) CDI is partially deflected even with NAV flag shown

This implementation better matches reality - at least, how I observed it ;-)