rsc3/doc-schelp/HelpSource/Classes/LeastChange.scrbl

96 lines
1.3 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{LeastChange}
Output least changed@section{related}
Classes/MostChange, Classes/LastValue
@section{categories}
UGens>Maths
@section{description}
Given two inputs
@racketblock[a:: and ]
@racketblock[b::, let ]
@racketblock[da[t] = abs(a[t] - a[t - 1]):: and ]
@racketblock[db[t] = abs(b[t] - b[t - 1])::. Output ]
@racketblock[a[t]:: if ]
@racketblock[da[t]:: is smaller, and output ]
@racketblock[b[t]:: if ]
@racketblock[db[t]:: is smaller. If ]
@racketblock[da[t] == db[t]::, use whichever input was used last (assume ]
@racketblock[a:: for the first sample of output).
]
@section{classmethods}
@section{method}
ar, kr
@section{argument}
a
Input signal A.
@section{argument}
b
Input signal B.
@section{examples}
@racketblock[
(
d = { arg amp=1.0;
var in1, in2;
in1 = LFNoise0.ar(800, amp);
in2 = SinOsc.ar(800);
LeastChange.ar(in1, in2) * 0.1;
}.play;
)
d.set(\amp, 0.1);
d.set(\amp, 0);
d.set(\amp, 3);
d.free;
::
the control that changed least is used as output:
]
@racketblock[
(
d = { arg freq=440;
var internalFreq;
internalFreq = LFNoise0.ar(0.3, 300, 800);
SinOsc.ar(
LeastChange.kr(freq, internalFreq) // two sources of change: one external, one internal
) * 0.1
}.play
);
d.set(\freq, 800);
d.set(\freq, 900);
d.free;
::
]