Pbrown brownian motion pattern

superclass: Pattern

Pbrown(lo, hi, step, length)

Returns a stream that behaves like a brownian motion. 

lo, hi - lower and upper boundary of values  (default: 0.0 and 1.0)

step - maximum change per step - the distribution is xrand2.  (default: 0.125)

length - number of values produced (default: inf)

See also: BrownNoise, Pgbrown

// example

(

var a;

a = Pbrown(0.0, 1.0, 0.1, inf);

c = a.asStream.nextN(500);

w = Window.new("Pbrown", Rect(10, 10, 540, 800));

// plot the values

c.plot(bounds: Rect(10, 10, 520, 380), discrete: true, parent: w);

// a histogram of the values

c.histo(500).plot(bounds: Rect(10, 410, 520, 380), parent: w);

)

(

var a;

a = Pbrown(0.0, 1.0, 0.2, inf);

a.asStream.nextN(1000).plot;

)

// sound example

(

SynthDef(\help_sinegrain, 

{ arg out=0, freq=440, sustain=0.05;

var env;

env = EnvGen.kr(Env.perc(0.01, sustain, 0.2), doneAction:2);

Out.ar(out, SinOsc.ar(freq, 0, env))

}).add;

)

(

var a;

a = Pbrown(0.0, 1.0, 0.1, inf).asStream;

{

loop {

Synth(\help_sinegrain, [\freq, a.next * 600 + 300]);

0.02.wait;

}

}.fork;

)

// parallel browninan motions

(

var a, x, f;

a = Pbrown(0.0, 1.0, 0.1, inf);

f = { |pattern, dt=0.02, min=300, max=900|

{

var x = pattern.asStream;

loop {

Synth.grain(\help_sinegrain, [\freq, x.next.linexp(0, 1, min, max), \sustain, dt]);

dt.wait;

}

}.fork;

}.flop;

// 3 parallel motions

f.(a, [0.02, 0.08, 0.16]);

)