POV-Ray : Newsgroups : povray.unofficial.patches : FFT internal function? : Re: FFT internal function? Server Time27 Mar 2023 07:13:52 EDT (-0400)
 Re: FFT internal function?
 From: Bald Eagle Date: 6 Feb 2017 10:15:01 Message:
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clipka <ano### [at] anonymousorg> wrote:

> You'd need to provide a use case though, and one or more proposals for
> the scene description syntax, as I've never used FFT in the context of
> raytracing, so I have no bloody idea what it could be used for in POV-Ray ;)

I'll see what I can do.

As with many things, it's a tool that looks very useful, and something I'd like
to explore.

I had wanted to use it for "simple" signal processing - to extract the
fundamental frequencies of the data in the vibrating plate animation I did.
I'm sure that given the various transcendent, repeating, and other functions
that are used to generate various scene elements, that some clever person could
apply the Fourier transform and its inverse to do some wicked cool stuff that I
can't currently imagine or articulate.  ;)

From some of my reading, it looks like it can be used for some formas of
antialiasing, image deconvolution (sharpening), simulating types of noise, water
surfaces, etc.

http://www.bugman123.com/Fractals/index.html
(CTRL-F to search for 'fourier')
Frequency Filtered Random Noise - Mathematica 4.2, 9/5/04

http://www.bugman123.com/Physics/index.html#Caustics
"Water Caustics - Mathematica 4.2, POV-Ray 3.1, 4/22/06
This water-like surface was generated in Mathematica using frequency filtered
random noise, and then it was raytraced in POV-Ray and water caustics were added

http://www.bialith.com/Research/BARclockblur.htm
http://www.deconvolve.net/index.html
```