Hi there, just thought I’d mention my new SimplexNoise-SC Quark, now in the main repository (just update your Quarks to see and install it, using Quarks.gui). It’s based on a public domain Java implementation of Simplex noise by Stefan Gustavson (and has his enthusiastic blessing ;-).
It is somewhat similar to the RedPerlin class from Frederik’s redUniverse, although that one isn’t actually Perlin (gradient-based) noise, it seems to be interpolated “value noise”. On the Server side, we have the Perlin3 UGen (although it has the unpleasant effect (bug?) of returning 0 a lot of the time, so it’s extra noisy (in the audio sense!), not being very continuous).
There is a different character to value noise vs Perlin noise vs Simplex noise (although the last two are gradient-based, so they’re more closely related).
You’ll find some basic examples in the Simplex class help page – you can use it to draw noisy pictures, create fake stock market graphs, or generate a set of “related” periodic Waveforms for Osc.ar synthesis.
(0,0.01..10).collect{ |x| Simplex.fBm2(x, 33.3, 8); }.plot
To get different noise, offset the coordinates. Nearby coordinates (e.g. change
yfrom 33.3 to 33.35) will produce different but “similar” results.
You can use it generate continuous streams of pseudo-random data for musical Events (similar to Pbrown, except that it’s more predictable and smoothly interpolated, and you can do things like make it periodic – a trick I like to do, by moving on a closed path through the higher noise dimensions).
You can use Simplex.periodic to make periodic waveforms that evolve over subsequent cycles if you gradually shift the offset:
(0,0.01..10).collect{ |x| Simplex.periodic(x, [0.02 * x, 3]); }.plot
And here is a teaser that generates an evolving melody (notes and durations) using a Routine (Prout):
(
f = { arg periodSteps = 8, variationRate = 0.005, offset = #[13, 14];
{
var x = 0;
loop{
Simplex.periodic(x, [variationRate * x, 0] + offset).yield;
x = x + periodSteps.reciprocal;
}
}.p
}
)
(
p = Pbind(
\degree, f.(8).linlin(-1.2,1.2,-14,7).round,
\dur, Pindex([Rest(0.125), 0.125,0.25,0.5,1], f.(16, offset: 77).linlin(-1,1,0,4.99).asInteger)
).play
)
p.stop
I will likely add a Pattern class to the Quark, to do something similar to the above f function (generate a series of periodic random value events), if I can settle on a name: Pperiodic, Psimplex, Pprand, Pcycrand, …? Any preferences?
I find this kind of pseudo-noise musically very useful and a source of all kinds of creative ideas; let me know if you find your own neat use for it. And any suggestions or (friendly) criticisms are welcome!
Glen.