112 lines
1.6 KiB
Racket
112 lines
1.6 KiB
Racket
#lang scribble/manual
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@(require (for-label racket))
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@title{PV_ConformalMap}
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Complex plane attack.@section{related}
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Classes/FFT, Classes/IFFT
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@section{categories}
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UGens>FFT
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@section{description}
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Applies the conformal mapping
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@racketblock[
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z → (z - a) / (1 - za*)
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::
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to the phase vocoder bins z with a given by the real and imag inputs to
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the UGen.
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Makes a transformation of the complex plane so the output is full of
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phase vocoder artifacts but may be musically fun. Usually keep
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]
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@racketblock[
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|a| < 1
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::
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but
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you can of course try bigger values to make it really noisy.
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]
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@racketblock[
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a = 0
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::
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should
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give back the input mostly unperturbed.
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See link::http://mathworld.wolfram.com/ConformalMapping.html:: .
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]
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@section{classmethods}
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@section{method}
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new
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@section{argument}
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buffer
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FFT buffer.
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@section{argument}
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areal
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Real part of a.
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@section{argument}
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aimag
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Imaginary part of a.
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@section{Examples}
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@racketblock[
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//explore the effect
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(
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SynthDef("conformer1", {
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var in, chain;
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in = SoundIn.ar(0, 0.5);
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chain = FFT(LocalBuf(1024), in);
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chain=PV_ConformalMap(chain, MouseX.kr(-1.0,1.0), MouseY.kr(-1.0,1.0));
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Out.ar(0, Pan2.ar(IFFT(chain),0));
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}).add;
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)
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a = Synth("conformer1")
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a.free
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(
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SynthDef("conformer2", {
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var in, chain, out;
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in = Mix.ar(LFSaw.ar(SinOsc.kr(Array.rand(3,0.1,0.5),0,10,[1,1.1,1.5,1.78,2.45,6.7]*220),0,0.3));
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chain = FFT(LocalBuf(2048), in);
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chain=PV_ConformalMap(chain, MouseX.kr(0.01,2.0, 'exponential'), MouseY.kr(0.01,10.0, 'exponential'));
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out=IFFT(chain);
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Out.ar(0, Pan2.ar(CombN.ar(out, 0.1, 0.1, 10, 0.5, out), 0, 0.3));
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}).add;
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)
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a = Synth("conformer2")
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a.free
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::
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]
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