"Tek" <tek### [at] evilsuperbraincom> wrote:
> Le_Forgeron <lef### [at] freefr> wrote:
> > Le 12/11/2010 11:36, Tek a écrit :
> >
> > > Quite simply, I have no way to guarantee, or even to make it likely, that pixels
> > > on the next frame will use a different blur sample to this frame.
> > >
> >
> > If you use a deterministic pattern (whatever it be, with high contrast
> > area in <0,0><1,1>...) then from frame to frame, you can rotate and
> > translate it as your seed wants to govern it. you might for instance use
> > a checkered b&w, scaled to 1/10 (so that's potentially 50 spots out of
> > 100), rotated on the plane by a random value (your choice of seed),
> > translated randomly...
>
> I'm pretty sure that's what I just said.
>
> e.g. I sample the bokeh filter for a pixel this frame and it hits a white bit,
> so the sample goes through in that position. On the next frame I try to sample
> the exact same position (because the halton sequence is the same), but I've
> animated the bokeh pattern so there's a 50% chance it will hit white again. If
> it does then the sample is in the same position, not animated.
>
> So 50% of the noise from one frame to the next will be identical, not random. Am
> I missing something?

So basically you want a pattern with ~50% average brightness that's guaranteed
to be black in spots that haven't been sampled in the last N frames?

That's...  possible, but ugly.  You'd need to look at the source to determine
the primes being used for the Halton sequence in question, then design your
pattern around that.

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