"Christoph Hormann" <chr### [at] gmxde> schreef in bericht
news:3E0F156E.AB321B83@gmx.de...
> Zeger Knaepen wrote:
> >
> > > Because it uses a fixed table for the sample directions.  If you know
a
> > > way for generating an arbitrary number of sample directions on the fly
> > > with random yet uniform distribution (and cos theta density
distribution)
> > > you are welcome to share it... ;-)
> >
> > Why is a fixed table necessary?
>
> Have you read what i wrote?
Yep, and although I did misunderstand your question :) , my question
remains: if it's possible to calculate 1600 fixed sample directions, it
should also be possible (using the same or a similar algorythm) to calculate
an arbitrary amount of fixed sample directions before the actual raytracing
starts.  That way, you don't have to calculate the sample directions on the
fly, and there wouldn't be an upperlimit of 1600 samples.  Or am I talking
nonsense here?

> I don't know a method to generate such a distribution in high quality that
> would be fast enough to be run before every render - if you do feel free
> to implement it.
I don't know what a "cos theta density distribution" is, but aren't just
random (and not (perfectly) uniform distributed) rays good enough?

Oh, and an other question: reading the POV-Ray manual gave me the impression
that the re-use of samples is based on the distance of the previous sample.
As far as I can remember, there's nothing about the surface-normal in the
manual.  But IMHO, the surface normal is more (or equaly) important to
decide if samples could be re-used.  Am I wrong?  Or is this maybe already
implemented?
Just a thought... :)  Don't shoot me if I'm wrong :)

cu!
--
ZK AKA SaD
http://www.povplace.be.tf
"Smoke me a kipper, I'll be back for breakfast."

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