I recently made a post about rolling your own random noise generators 
with f_hash() over in the v4.0 forum:

https://news.povray.org/povray.pov4.discussion.general/thread/%3C674b018b%40news.povray.org%3E/

I found myself with a few hours to burn this afternoon so I gave 
creating a special noise video a try based upon f_hash(). The core
of the code is:

     #include "functions.inc"
     #declare Seed00 = 7834.5540283051168443;
     #declare Delta = 880+frame_number*0.00002;
     #declare Step = sqrt(Delta)      *0.00025;

     #declare Fn2Dlen = function (x,y) {
         f_2x_f32_vlength(f_enc2x_f32(x,y))
     }
     #declare Fn00 = function {
         f_hash(
             (
             f_hash(Fn2Dlen(x+Delta,y+Delta),Seed00,Step,0)+
             f_hash(Fn2Dlen(x-Delta,y+Delta),Seed00,Step,0)+
             f_hash(Fn2Dlen(x+Delta,y-Delta),Seed00,Step,0)+
             f_hash(Fn2Dlen(x-Delta,y-Delta),Seed00,Step,0)
             ),
         Seed00,0,0)
     }

     #declare Pigm00 = pigment {
         function { Fn00(x,y,z) }
     }

Above there are four distance to x,y coordinate based f_hash()s feeding 
a final f_hash() function - all using the same seed value. An mp4 video 
attached.

Bill P.

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Attachments:
Download 'try.mp4.dat' (2790 KB)

William F Pokorny <ano### [at] anonymousorg> wrote:
> I recently made a post about rolling your own random noise generators
> with f_hash() over in the v4.0 forum:
>
>
https://news.povray.org/povray.pov4.discussion.general/thread/%3C674b018b%40news.povray.org%3E/
>
> I found myself with a few hours to burn this afternoon so I gave
> creating a special noise video a try based upon f_hash(). The core
> of the code is:
>
>      #include "functions.inc"
>      #declare Seed00 = 7834.5540283051168443;
>      #declare Delta = 880+frame_number*0.00002;
>      #declare Step = sqrt(Delta)      *0.00025;
>
>      #declare Fn2Dlen = function (x,y) {
>          f_2x_f32_vlength(f_enc2x_f32(x,y))
>      }
>      #declare Fn00 = function {
>          f_hash(
>              (
>              f_hash(Fn2Dlen(x+Delta,y+Delta),Seed00,Step,0)+
>              f_hash(Fn2Dlen(x-Delta,y+Delta),Seed00,Step,0)+
>              f_hash(Fn2Dlen(x+Delta,y-Delta),Seed00,Step,0)+
>              f_hash(Fn2Dlen(x-Delta,y-Delta),Seed00,Step,0)
>              ),
>          Seed00,0,0)
>      }
>
>      #declare Pigm00 = pigment {
>          function { Fn00(x,y,z) }
>      }
>
> Above there are four distance to x,y coordinate based f_hash()s feeding
> a final f_hash() function - all using the same seed value. An mp4 video
> attached.
>
> Bill P.

This is hypnotic, but maybe too small scaled to let us gaze at its evolution...
Unless it can't show bigger cells ?

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On 12/2/24 05:47, Mr wrote:
> This is hypnotic, but maybe too small scaled to let us gaze at its evolution...
> Unless it can't show bigger cells ?

Thanks. It's admittedly a bit small at its native size. It was what I 
could do quickly while aiming for a 10 second animation at under 3MB. If 
your browser or viewer supports a full screen mode, you might find it 
some help - my old eyes do.

I have a two minute animation in my space with a slightly larger pixel 
resolution, larger 'noise-steps' and a much slower frame rate. The 
slower frame rate is better for viewing the evolution. The mp4, though, 
is a little over 29MB. I've attached the last frame of that animation.

The slower frame rates compress much less well (with my ffmpeg novice 
settings).

Bill P.

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Attachments:
Download 'asrandomnoiseon_xyz480.jpg' (140 KB)

Preview of image 'asrandomnoiseon_xyz480.jpg'