On 11/6/24 13:26, Bald Eagle wrote:
> How many Voronoi "seeds" are there in the unit cube before you reach the "edge"
> and there is a repeat?  Is that / can that be a variable?

The is one seed point per unit cubelet. To do the repeat the overall 
5x5x5 cube gets re-created as the evaluation point moves to another 
centered global cubelet location (tracked with unsigned integers in yuqk).

A trick of the repeat is to wrap in both in the forward direction as 
each x,y,z change - but also behind so the local 'center' see an 
environment valid for the range of supported distances(*).

(*) In yuqk the ip_strength vector lets you use >1.0 vector components 
and exceed the technically supported distances. Same can happen if the 
ip_exponent of the '0' / power ip_metric is <1.0. You still get a result 
usable for effect, but it doesn't look like a standard crackle / Voronoi 
result.

The repeat values are user variables.

The size of the supported cache for cubes of cubelets environments is 
done with build options / environment variables.

To date the max size of the cuble for experimentation is manually hacked 
into the code - I'm not sure what all I might be doing there in the end.

> 
> What are you doing at the edges/corners to make a space-filling tesselation by
> that "unit cube" of Voronoi pattern?  Essentially just a mod (<x, y, z>, N)?

Yes, fmod() (SDL's mod()) gets used to set up both the cubelet locations 
and the repeated cubelets.

With this I think the code is the best answer. In my re-write, I 
flattened the code so there is little (no?) jumping around in the 
overall code base required to see what is going on. Last time I counted, 
yuqk's crackle was roughly 400 lines of code or so. See:

CracklePattern::EvaluateRaw() in source/core/material/pattern.cpp

Bill P.

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