Warp wrote:

> Greg M. Johnson <pte### [at] thecommononethatstartswithycom> wrote:
>> If the phenomenon I observed is valid, then it could be helpful to have
>> an less-predictable value by setting the seed based on something that
>> varies wildly as a function of frame_number: I was using cos & sin.
> 
>   What do you mean by "less predictable"?
> 
>   From any value returned by the random number generator it's possible
> to predict the next values. POV-Ray's RNG uses a very simple algorithm.
> 


Okay.  To restate, say I do this:

#declare RRR=seed(frame_number);
#declare a01=rand(RRR);
#declare a02=rand(RRR);
#declare a03=rand(RRR);
#declare a04=rand(RRR);
#declare a05=rand(RRR);
#declare a06=rand(RRR);
#declare a07=rand(RRR);
#declare a08=rand(RRR);
#declare a09=rand(RRR);
#declare a10=rand(RRR);
...
#declare an=rand(RRR);


Then for some n, n<20, if I then go plot out the values of an as a function
of frame_number when rendered, one of those values would be a straight
line. One but surely not all. 

That's not exactly predictable but it's entirely non random.

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