[Flightgear-devel] enhanced runway lighting.

[Curtis L. O. <cur...@fl...>]

I was fiddling with enhance runway lighting tonight and was wondering if 
we are using the distance attenuation extention optimally?

It appears that we specify a point size of 4.  As the lights get further 
in the distance they fade in terms of alpha, but they don't ever get 
smaller.  This makes the lights look really blurry and overlap in the 
distance ... kind a weird unnatural effect.

The spec seems to imply that it will change the point size until it hits 
a threshold (default =1.0) and below that it will start fading in alpha 
to approximate smaller point sizes.

However, with the quadratic coefficients we have, we never seem to get 
any smaller points, only the alpha fading.  This is on an nvidia card.

I played around with the quadratic coefficients and attempted to get 
smart about fitting the desired function so I could control point size 
versus distance.  But I could never get the point sizes to shrink.  In 
fact, I couldn't really get the display to change at all.

Am I misunderstanding something about the spec?  Is there something 
broke?  Does this extention not play well with our directional runway 
lighting scheme?

I think we ought to be able to do a lot better than what I'm seeing here 
on my hardware.  Any ideas?

Thanks,

Curt.

-- 
Curtis Olson        http://www.flightgear.org/~curt
HumanFIRST Program  http://www.humanfirst.umn.edu/
FlightGear Project  http://www.flightgear.org
Unique text:        2f585eeea02e2c79d7b1d8c4963bae2d