rsc3/doc-schelp/HelpSource/Classes/Gendy3.scrbl

#lang scribble/manual
@(require (for-label racket))

@title{Gendy3}
 Dynamic stochastic synthesis generator.@section{related}
  Classes/Gendy1, Classes/Gendy2
@section{categories}
   UGens>Generators>Stochastic


@section{description}


See  link::Classes/Gendy1::  help file for background. This variant of
GENDYN normalises the durations in each period to force oscillation at
the desired pitch. The breakpoints still get perturbed as in
link::Classes/Gendy1:: .

There is some glitching in the oscillator caused by the stochastic
effects - control points as they vary cause big local jumps of amplitude.
Put  
@racketblock[ampscale::  and  ]

@racketblock[durscale::
low to minimise the rate of this.

SuperCollider implementation by Nick Collins

]
@section{classmethods}
 

@section{method}
 ar, kr

@section{argument}
 ampdist

Choice of probability distribution for the next perturbation of
the amplitude of a control point.

The distributions are (adapted from the GENDYN program in Formalized Music):

@section{table}
 
## 0: || LINEAR.
## 1: || CAUCHY.
## 2: || LOGIST.
## 3: || HYPERBCOS.
## 4: || ARCSINE.
## 5: || EXPON.
## 6: || SINUS.
::

Where the sinus (Xenakis' name) is in this implementation taken
as sampling from a third party oscillator. See example below.


@section{argument}
 durdist

Choice of distribution for the perturbation of the current inter
control point duration.


@section{argument}
 adparam

A parameter for the shape of the amplitude probability
distribution, requires values in the range 0.0001 to 1 (there are
safety checks in the code so don't worry too much if you want to
modulate!).


@section{argument}
 ddparam

A parameter for the shape of the duration probability
distribution, requires values in the range 0.0001 to 1.


@section{argument}
 freq

Oscillation frequency.


@section{argument}
 ampscale

Normally 0.0 to 1.0, multiplier for the distribution's delta
value for amplitude. An ampscale of 1.0 allows the full range
of  -1 to 1 for a change of amplitude.


@section{argument}
 durscale

Normally 0.0 to 1.0, multiplier for the distribution's delta
value for duration. An ampscale of 1.0 allows the full range of
-1 to 1 for a change of duration.


@section{argument}
 initCPs

Initialise the number of control points in the memory.
Xenakis specifies 12. There would be this number of control
points per cycle of the oscillator, though the oscillator's
period will constantly change due to the duration distribution.


@section{argument}
 knum

Current number of utilised control points, allows modulation.

@section{argument}
 mul

@section{argument}
 add

@section{discussion}
 
All parameters can be modulated at control rate except for 
@racketblock[initCPs:: which is used only at initialisation.


]
@section{Examples}
 


@racketblock[

//LOUD! defaults like a rougher Gendy1
{Pan2.ar(Gendy3.ar(mul:0.5))}.play

{Pan2.ar(Gendy3.ar(freq:MouseX.kr(220,880,'exponential'), durscale:0.01, ampscale:0.02, mul:0.2))}.play

//stochastic waveform distortion- also play me at the same time as the previous example...
{Pan2.ar(Gendy3.ar(1,2,0.3,-0.7,MouseX.kr(55,110,'exponential'),0.03,0.1))}.play


(
{Pan2.ar(
Normalizer.ar(
RLPF.ar(
RLPF.ar(Mix.new(Gendy3.ar(freq:[230, 419, 546, 789])),
MouseX.kr(10,10000,'exponential'),0.05),
MouseY.kr(10,10000,'exponential'),0.05)
,0.9)
,Lag.kr(LFNoise0.kr(1),0.5))}.play
)


//concrete pH?
(
{Pan2.ar(
Mix.new(Gendy3.ar(freq:([1,1.2,1.3,1.76,2.3]*MouseX.kr(3,17,'exponential')),mul:0.2)))}.play
)

//glitch low, mountain high
(
{Pan2.ar(
Mix.new(Gendy3.ar(3,5,1.0,1.0,(Array.fill(5,{LFNoise0.kr(1.3.rand,1,2)})*MouseX.kr(100,378,'exponential')),MouseX.kr(0.01,0.05),MouseY.kr(0.001,0.016),5,mul:0.1)))}.play
)

//play me
{Pan2.ar(RLPF.ar(Gendy3.ar(1,3,freq:MouseX.kr(100,1000), durscale:0.0, ampscale:MouseY.kr(0.0,0.1), initCPs:7, knum: MouseY.kr(7,2)), 500,0.3, 0.2), 0.0)}.play



//used as an LFO
(
{Pan2.ar(SinOsc.ar(Gendy3.kr(2,5,SinOsc.kr(0.1,0,0.49,0.51),SinOsc.kr(0.13,0,0.49,0.51), 0.34, SinOsc.kr(0.17,0,0.49,0.51), SinOsc.kr(0.19,0,0.49,0.51),10,10,mul:50, add:350), 0, 0.3), 0.0)}.play
)

//buzzpipes
{Pan2.ar(Mix.new(Gendy3.ar(0, 0, SinOsc.kr(0.1, 0, 0.1, 0.9),1.0, [100,205,410], 0.011,0.005, 12, 12, 0.12)), 0.0)}.play


//modulate distributions
//change of pitch as distributions change the duration structure and spectrum
{Pan2.ar(Gendy3.ar(MouseX.kr(0,7),MouseY.kr(0,7),mul:0.2), 0.0)}.play


//modulate num of CPs
{Pan2.ar(Gendy3.ar(knum:MouseX.kr(2,13),mul:0.2), 0.0)}.play


//Gendy1 into Gendy2 into Gendy3...with cartoon side effects
(
{Pan2.ar(Gendy3.ar(1,2,freq:Gendy2.ar(maxfreq:Gendy1.kr(5,4,0.3, 0.7, 0.1, MouseY.kr(0.1,10), 1.0, 1.0, 5,5, 25,26),minfreq:24, knum:MouseX.kr(1,13),mul:150, add:200), durscale:0.01, ampscale:0.01, mul:0.1), 0.0)}.play
)

//use SINUS to track any oscillator and take CP positions from it, use adparam and ddparam as the inputs to sample
{Pan2.ar(Gendy3.ar(6,6,LFPulse.kr(LFNoise0.kr(19.0,0.5,0.6), 0, 0.4, 0.5), Gendy1.kr(durscale:0.01,ampscale:0.01), MouseX.kr(10,100),mul:0.2), 0.0)}.play



//wolf tones
(
{
Mix.fill(10,{
var freq;

freq= exprand(130,1160.3);
Pan2.ar(SinOsc.ar(Gendy3.ar(6.rand,6.rand,SinOsc.kr(0.1,0,0.49,0.51),SinOsc.kr(0.13,0,0.49,0.51),freq, SinOsc.kr(0.17,0,0.0049,0.0051), SinOsc.kr(0.19,0,0.0049,0.0051), 12, 12, 200, 400), 0, 0.1), 1.0.rand2)
});
}.play
)

//CAREFUL! mouse to far right causes explosion of sound-
//notice how high frequency and num of CPs affects CPU cost
(
{Pan2.ar(
CombN.ar(
Resonz.ar(
Gendy3.ar(2,3,freq:MouseX.kr(10,700), initCPs:100),
MouseY.kr(50,1000), 0.1)
,0.1,0.1,5, 0.16
)
, 0.0)}.play
)


//storm
(
{
var n;
n=15;

0.5*Mix.fill(n,{
var freq, numcps;

freq= rrand(130,160.3);
numcps= rrand(2,20);
Pan2.ar(Gendy3.ar(6.rand,6.rand,10.0.rand,10.0.rand,freq*exprand(1.0,2.0), 10.0.rand, 10.0.rand, numcps, SinOsc.kr(exprand(0.02,0.2), 0, numcps/2, numcps/2), 0.5/(n.sqrt)), 1.0.rand2)
});
}.play
)



//another glitchy moment
(
{
var n;
n=10;

Resonz.ar(
Mix.fill(n,{
var freq, numcps;

freq= rrand(50,560.3);
numcps= rrand(2,20);
Pan2.ar(Gendy3.ar(6.rand,6.rand,1.0.rand,1.0.rand,freq, 1.0.rand, 1.0.rand, numcps, SinOsc.kr(exprand(0.02,0.2), 0, numcps/2, numcps/2), 0.5/(n.sqrt)), 1.0.rand2)
})
,MouseX.kr(100,2000), MouseY.kr(0.01,1.0), 0.3)
;
}.play
)
::

]