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

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

@title{PatternProxy}
 stream reference@section{categories}
  Libraries>JITLib>Patterns, Live Coding
@section{related}
  Classes/Pdefn

@section{description}

Keeps a reference to a stream that can be replaced while playing. Multiple streams are thus handled without creating dependencies.

@section{ClassMethods}
 

@section{private}
 at, hasGlobalDictionary, parallelise, postRepository, removeAll, basicNew, clear, event

@section{method}
 new
create a new instance with a pattern (the source). the pattern should be a emphasis::value pattern:: (see link::Classes/Pdefn::).

for event pattern proxy, see: link::Classes/EventPatternProxy::. instead of a pattern, a strong::function:: can be passed in, creating a routine.

@section{method}
 default
a default source, if none is given. the default is 1.0 (it is not 0.0 in order to make it safe for durations)

@section{method}
 defaultQuant
set the default quantization value for the class. (default: nil)

@section{method}
 defaultValue
a default return value, if no source is given. the default is 1.0 (it is not 0.0 in order to make it safe for durations). This is used in link::#-endless::.

@section{InstanceMethods}
 

@section{method}
 asStream
Return a link::Classes/Stream:: from this pattern. One pattern proxy can be used to produce any number of independent streams.


@racketblock[
a = PatternProxy.new;
a.source = Pgeom(1, Pwhite(1.01, 1.2), inf);
b = a.asStream; c = a.asStream;

b.next;
b.next;
b.next;

c.next; // c is independent from b
c.next;

a.source = Pgeom([1, 2, 3], Pwhite(1.01, 1.2), inf); // replace the source

b.next;
c.next;

::

]
@section{method}
 embedInStream
Given a link::Classes/Stream:: like e.g. link::Classes/Routine::, yield all values from the pattern in the proxy before continuing. One pattern proxy can be used to produce values for any number of independent streams.

@section{argument}
 inval
The inval is passed into all substreams and can be used to control how they behave from the outside.

@section{argument}
 embed
See link::Classes/Object#-streamArg:: for explanation.

@section{argument}
 default
Replacement for 
@racketblock[nil:: outputs of the source pattern. One use case is link::#-endless::.

]

@racketblock[
a = PatternProxy.new;
a.source = Pgeom(1, Pwhite(1.01, 1.2), 4);
r = Routine { loop { 2.yield; 3.yield; a.embedInStream }; };
r.nextN(12); // the next 12 values from r
a.source = Pgeom([1, 2, 3], Pwhite(1.01, 1.2), inf); // replace the source
r.nextN(12); // the next 12 values from r
::


]
@section{method}
 source
set the source. If a quantization is given, schedule this change to the next beat

@section{method}
 clear
set the source to nil

@section{method}
 quant
set or get the quantization value

@section{method}
 condition
provide a condition under which the pattern is switched when a new one is inserted. the stream value and a count is passed into the function. the methods strong::count_(n):: simply counts up to n and switches the pattern then

@section{method}
 embedInStream
just like any pattern, embeds itself in stream

@section{subsection}
 Methods implemented for subclasses

PatternProxy implements some methods for the benefits of its subclasses link::Classes/Pdefn:: / link::Classes/Pdef:: / link::Classes/Tdef:: which are not useful for link::Classes/PatternProxy:: and link::Classes/TaskProxy::.

@section{method}
 envir
provide a default environment for the proxy. If given, it is used as an environment for the routine function. When set for the first time, the routine pattern is rebuilt.

@section{method}
 set
set arguments in the environment. If there is none, it is created and the pattern is rebuilt.

@section{method}
 endless
returns a Prout that plays the proxy endlessly, replacing strong::nil:: with a strong::default:: value (1). This allows to create streams that idle on until a new pattern is inserted.

@section{Examples}
 


@racketblock[
a = PatternProxy(Pseq([1, 2, 3], inf));

x = Pseq([0, 0, a], inf).asStream;

t = Task({ loop({ x.next.postln; 0.3.wait }) }).play;


a.source = Pseq([55, 66, 77], inf);
a.source = Pseq([55, 66, 77], 1);

t.stop;
::

]

@racketblock[
// PatternProxy, like Pdefn can be accessed in multiple streams

(
SynthDef("Pdefhelp", { arg out, freq, sustain=1, amp=1, pan;
	var env, u=1;
	env = EnvGen.kr(Env.perc(0.03, sustain), 1, doneAction: Done.freeSelf);
	5.do { var d; d = exprand(0.01, 1); u = SinOsc.ar(d * 300, u, rrand(0.1,1.2) * d, 1) };
	Out.ar(out, Pan2.ar(SinOsc.ar(u + 1 * freq, 0, amp * env), pan));

}).add;
s.boot;
)

(
x = PatternProxy.new;
x.source = Pseq([0, 3, 2], inf);

Pset(\instrument, \Pdefhelp,
	Ppar([
	Pbind(\degree, x),
	Pbind(\degree, x, \dur, 1/3)
])
).play;
)

x.source = Prand([0, 3, [1s, 4]], inf);

x.source = Pn(Pshuf([0, 3, 2, 7, 6], 2), inf);



// if quant is set, the update is done at the next beat or whatever is specified:

x.quant = 4;
x.source = Pn(Pseries(0, 1, 8), inf);

x.quant = nil; // reactivate immediacy

(
x.source = Prout {
	loop {
	4.do { |i|
		#[2, 3, 4].choose.yield;
		#[5, 0, 11].choose.yield;
		#[6, 3, 4].choose.do { |j| (i % j).yield };
	}
	}
}
)
::
]