POV-Ray : Newsgroups : povray.unofficial.patches : Bug in glow calculation? : Re: Bug in glow calculation? Server Time
1 Sep 2024 22:19:31 EDT (-0400)
  Re: Bug in glow calculation?  
From: Nicolas Calimet
Date: 18 Oct 2000 09:11:26
Message: <39EDA30A.8F60D91@free.fr>
> They don't do what you want, but it is not a bug. The size keyword is
> buggy, but fade_power does exactly what it is supposed to do: it adjusts
> the final results of the glow falloff functions. This causes an
> unrealistic result when reflected or seen through transparent objects,
> but that is not a bug in the feature.

	But Warp mentionned that the result is wrong also when the transparent
object is *behind* the glow, and that's true. He was right when he said that it
might be a problem of ray length (my guess).
	In the Do_Glow code, the scattering depends both on the last intersection
found (Ray->Initial) and the next one (through Depth). I would expect the glow
to depend mostly on the Frame.Camera->Location which distance is constant to the
glow, and not from Ray->Initial that may change due to transparent objects. But
replacing that is not enough, Depth should be corrected also. Yet I didn't find
how. I also wonder how refraction would work...
	Or am I completely wrong ?
	Chris, I'm sure you know the answer ;-)


*** Nicolas Calimet
*** http://pov4grasp.free.fr


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