random seed not initialized by global variation?

Hi Sphinx,

I ran into that same thing, this is what Vlad had to say.

I do agree it should be connected by default.

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ThreeDee wrote: Quote Vladimir Golovin wrote: You can the VARIATION variable, which is visible to scripts that have the "Makes use of the global Variation setting" flag turned on in their Script Settings. Ok, thanks, I got that now. You can control the variations by calling math.randomseed(VARIATION) during prepare. Without this, the random numbers were different EVERY time, even when using a stored preset, which is fine if you wanted it to be that way, but if the variation happed to the exact one you wanted to keep... TD

THreeDee, I have the same question as Sphinx, I tried this before you wrote this and got the same errors as Sphinx.

Yes, that's the place, right under your script input field when you are in edit mode and have a Script component selected. The global Size slider and a few other things are there, too.

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Sphinx. wrote: Use of math.random will create variations from rendering to rendering even though global variation slider has not been changed.

That shouldn't happen. We'll investigate this.

yeah, but I'm not sure this is really a problem anymore

function prepare()
math.randomseed(VARIATION)
rx = math.random() - 0.5
ry = math.random() - 0.5
end;

function get_sample(x, y)
return get_sample_map(x + rx, y + ry, SOMETHING)
end;

if "Makes use of the global variation setting" is not checked, you will get a script error because VARIATION is nil, but I don't think thats a bug - any other nil variable would cause this too, its expected behaviour I'd say. But perhaps you should set VARIATION even when the "Makes use.." option is not checked?

Now if you do not set the randomseed at all (but have "Makes use.." checked), the position will change for every new rendering. This non deterministic behaviour is not ok I think. You should initialize the randomseed with a constant before rendering.