[Sidefx-houdini-list] One dimensional noise() expression??

Pablo Giménez pablogipi at gmail.com
Mon Mar 8 10:17:57 EST 2010


2010/3/8 François Duchesneau <sidefx at trinix.ca>

> You can create your own expression like this and use it like that in a
> position y of a Point Sop.
> noise1d($TX*1.3)
>
> # New function noise1d
> noise1d(val)
> {
> vector nresult = noise(val, 1.1435, 993.782);
> return nresult[1];
> }
>
> You could even create with that signature noise1d(val, freq, offset) to
> make things easier.
>
> I almost don't use Point Sop anymore, just to set normals to point or
> something like that. I prefer to do everything in Vop Sop and the
> Anti-Aliased Noise Vop allows you to do that out of the box and it's so
> much faster.
>

I also use vop sop almost for everything.
Thanks for the new expression function tip.


>
> François
>
> Chris Mangnall wrote:
> > perlin noise is always zero at lattice points (ie. integers), so
> >
> > noise($FF, rand($FF + 10), rand($FF  + 56))
> >
> > will always return 0 when $FF is an integer.
> > Try:
> >
> > noise($FF * 0.1, 0, 0)
> >
> > where 0.1 is the frequency.
> >
> >
> > Pablo Giménez wrote:
> >
> >> Hi there.
> >> Well many times I have been thinking about what useful would be to have
> one
> >> and tw odimensional noise() expressions.
> >> The current one needs three parameters, that is fine for a lot of
> situations
> >> but I really prefer to use a noise function ratehr than rand and having
> >> something like noise($F) would be good aI think.
> >> Maya noise function for instance allows this and is really handy.
> >>
> >> BTW I have tried to use expressions like:
> >> noise($FF, $FF + 10, $FF +56) and it always return 0, am I missing
> >> something?
> >> On the other side this works fine:
> >> noise($FF, rand($FF + 10), rand($FF  + 56))
> >> But I think is to heavy, I mean we are calculating 3 pseudo-ransom
> numbers
> >> in one call, too expensive.
> >> If I want to get a noise pattern but just from one value, what is the
> best
> >> way? Adding offset to every parameter, multiplying, although this will
> >> affect frequency ...
> >> Ideas welcome :)
> >> Cheers
> >>
> >>
> >>
> > _______________________________________________
> > Sidefx-houdini-list mailing list
> > Sidefx-houdini-list at sidefx.com
> > https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
> >
> >
> _______________________________________________
> Sidefx-houdini-list mailing list
> Sidefx-houdini-list at sidefx.com
> https://lists.sidefx.com:443/mailman/listinfo/sidefx-houdini-list
>



-- 
Un saludo
Best Regards
Pablo Giménez



More information about the Sidefx-houdini-list mailing list