The previous method of using a uniform scalar of the MSL wind speed for
higher altitudes didn't offer enough control. In particular, the shape
needs to be quite different to skew low, mid, high.
This patch reworks that system so the parameters of each distribution
are configured per-altitude level. To keep some continuity between
altitudes (on a windy day, all levels should have higher wind speeds on
average), the wind speed of the lower altitude will be added to the
scale value of the higher altitude.
Since it wasn't practical to approximate the previous behavior with the
new system, this also handles the tuning of each. The low altitude
speeds remain mostly unchanged (typically around 5 knots expect for
thunderstorms), but the average speeds for other altitudes went up to
more closely match the previous intent but without the massive
overshoot. At 2000m wind speeds are typically in the 20-25 knot range
now, and 8000m 30-50 knots.
https://www.quora.com/What-is-the-average-wind-speed-at-different-altitudes
has some of the source data, and Quora is the most authoritative source
there is. It claims that cruise altitude winds can get "as high as 150
knots", but doesn't claim anything about the average. I had a
surprisingly difficult time finding good data for cruise altitude air
speeds for non-jet stream paths (though many of our maps are in jet
streams), so I just eyeballed it from
https://turbli.com/wind-during-flights/.
https://github.com/dcs-liberation/dcs_liberation/issues/2861
Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2863.
Wind speeds should not be uniformly distributed. This switches to a
Weibull distribution which allegedly (see the bug) is good enough.
Experimentally that seems true as well, though I know nothing about how
wind works irl. This at least looks like it'll generate reasonable
variation in missions while keeping the 1st through 3rd quartile
behaviors from getting out of hand.
I'm very uncertain about the scaling factor aspect of this. Naively the
wind speeds at different altitudes ought to be somewhat correlated, but
I'm not sure how much, and whether this kind of scaling is at all the
right way to do it. As before, meh, close enough?
Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2861.
