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[supercollider.git] / HelpSource / Classes / Pdef.schelp

class:: Pdef
summary:: stream reference definition
categories:: Libraries>JITLib>Patterns
related:: Classes/Pdefn, Classes/PdefGui

description::
Pdef is a class that provides an interface to its superclass link::Classes/EventPatternProxy::, keeping a reference to a stream that can be replaced while playing. One pattern may be used in many streams in different places. A change in the pattern definition propagates through all streams.

code::
Pdef(key)       //returns the instance
Pdef(key, pat)  //stores the pattern and returns the instance, like Tdef and Ndef.
::

It can be used to store event Patterns globally. Changes in this global library have immediate effect.

For strong::non-event patterns:: link::Classes/Pdefn:: is used instead. For another use of Pdef see also link::Tutorials/JITLib/recursive_phrasing::. Graphical overview over all current Pdefs: link::Classes/PdefAllGui::. Overview: link::Overviews/JITLib::.

subsection::First Example

code::
s.boot;

Pdef(\x, Pbind(\note, Pbrown(0, 6, 0.1, inf)));
Pdef(\x).quant = 0; // no waiting.
Pbindf(Pdef(\x), \dur, 0.03).play;
Pbindf(Pdef(\x), \dur, 0.1, \ctranspose, 15).play;
Pbindf(Pdef(\x), \dur, 0.3, \ctranspose, 2).play;
// now change the definition
Pdef(\x, Pbind(\note, Pseq([0, 3, 5, 7, 9, 11], inf)));
Pdef(\x, Pbind(\freq, Pseq([1000, 1923, 245.2, 1718] / 1.2 + 0.1, inf)));
::

ClassMethods::

private::initClass

subsection::Creation

method::new
Store the pattern in a global dictionary under key, replacing its pattern with the new one. If the pattern is a strong::function::, Pdef creates a link::Classes/PlazyEnvir:: internall that dynamically creates the pattern returned from the function, applying the arguments from the inevent.

Using strong::*new(key):: you can access the pattern at that key (if none is given, a default silent event is created)

method::default
Default source, if none is given. The default is an Event.silent of 1.0 beat duration.

method::removeAll
Remove all proxies from the global dictionary ( link::#*all:: )

method::clear
Clear all proxies, setting their source to silence.

method::all
Set or return the environment ( link::Classes/IdentityDictionary:: ) that stores all Pdefs.

method::defaultQuant
Set the default quantisation for new instances (default: 1.0). This can be an array [quant, phase, timingOffset, outset]

InstanceMethods::

subsection::Changing the definition / setting the source

One pattern may have many streams in different places. A change in the pattern definition Pdef propagates through all streams. The change does not have to be immediate - there is a scheme to schedule when the change becomes effective: a strong::quant:: and strong::clock:: (like elsewhere) and a strong::condition::.

method::quant
Set the quantisation time for beat accurate scheduling.

argument::val
can be an array strong::[quant, phase, timingOffset, outset] ::, or just strong::[quant, phase]:: etc.

method::condition
Provide a condition under which the pattern is switched when a new one is inserted. The stream value and a count value is passed into the function.

method::count
Create and update condition that simply counts up to n and switches the pattern then

method::reset
Switch the pattern immediately (stuck conditions can be subverted by this).

method::fadeTime
When the synthdefs that are used contain an code::\amp:: control, the patterns are replaced by crossfading the previous with the new over this time (in beats)

method::envir
Set the event for the Pdef. It is used to filter the incoming stream before it is passed to the source pattern. This is similar to link::Classes/NodeProxy#-nodeMap::. When set for the first time, the pattern is rebuilt.

method::set
Set arguments in the default event. If there is none, it is created and the pattern is rebuilt.

method::map
Map Pdefn to the keys in the event.

method::clear
Set the source to nil

method::endless
Returns a link::Classes/Prout:: that plays the proxy endlessly, replacing strong::nil:: with a strong::default:: value (silent event). This allows to create streams that idle on until a new pattern is inserted.

subsection::Pdef as stream reference

A single Pdef may serve as a definition for multiple streams. These methods show how to fork off separate streams from one instance. Even if they run in different contexts, their definition may still be changed.

method::fork
Play an independent stream in parallel.

argument::quant
can be an array of [quant, phase, offset], or a link::Classes/Quant:: value.

method::embed
Pass a value (typically an link::Classes/Event::) into the pattern inval, and embed the Pdef in the stream.

embedInStream
just like any pattern, embeds itself in stream

subsection::Pdef as EventStreamPlayer

For live coding, each Pdef also may control one instance that plays one stream off it. This is an link::Classes/EventStreamPlayer::, accessible in the instance variable link::#-player::.

method::play
Starts the Pdef and creates a player.

argument::quant
can be an array of [quant, phase, offset] or a link::Classes/Quant:: value.

method::stop
Stops the player

method::player
Return the current player (if the Pdef is simply used in other streams this is nil)

method::pause, resume, reset
Perform this method on the player.

method::isPlaying
Returns true if player is running. If a Pdef is playing and its stream ends, it will schedule a stream for playing strong::as soon as a new one is assigned to it::. If it is stopped by strong::stop::, it won't.

Examples::

subsection::Pdef as stream reference

code::
(
SynthDef("Pdefhelp", { arg out, freq, sustain=1, amp=1, pan;
        var env, u=1;
        env = EnvGen.kr(Env.perc(0.03, sustain), 1, doneAction:2);
        3.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;

Pdef(\metronom, Pbind(\instrument, \Pdefhelp, \dur, 1, \degree, 16, \legato, 0.1)).play;

x = Pseq([Pdef(\a), Pdef(\b), Pdef(\c)], inf).play;

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.25, \degree, Pseq(#[0, 5, 4, 3])));
Pdef(\b, Pbind(\instrument, \Pdefhelp, \dur, 0.125, \degree, Pseq(#[7, 8, 7, 8])));
Pdef(\c, Pbind(\instrument, \Pdefhelp, \dur, 0.25, \degree, Pseq(#[0, 1, 2], 2)));




Pdef(\c, Pbind(\instrument, \Pdefhelp, \dur, 0.25, \degree, Pseq(#[4, 3, 1, 2]*3)));


// infinite loops are scheduled (to ths clock's next beat by default) and released:

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.753, \degree, Pseq(#[0, 5, 4, 3, 2], inf)));
Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.125, \degree, Pseq(#[0, 5, 4, 3] + 1, 1)));
Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.25, \degree, Pseq(#[0, 5, 4, 3] - 4, 1)));

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.125, \degree, Pseq(#[0, 5] - 1, 1)));
Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.753, \degree, Pshuf(#[0, 5, 4, 3, 2], inf)));

x.stop;
Pdef(\metronom).stop;

// Pdef can be used in multiple patterns:

(
x = Ppar([
        Pbindf(Pn(Pdef(\a), inf),
                \gtranspose, Pstutter(8, Pseq(#[0, 2, 0, 3],inf))
        ),
        Pbindf(Pn(Pdef(\a), inf),
                \gtranspose, Pstutter(8, Pseq(#[7, 4, 0, 3],inf)),
                \dur, 0.6
        ),
        Pbindf(Pn(Pdef(\a), inf),
                \degree, Pseq(#[0, 5, 4, 3, 2, 3, 2], 1)
        )
]).play;
)

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.1, \degree, Pseq(#[0, 1, 0, 1, 2], inf)));

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.2, \degree, Pseq([0, 4], inf)));

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 1, \degree, Pseq([0, 4], inf)));

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.2, \degree, Pseq([0, 4, Prand([6, 8b],2)], inf)));

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.1, \degree, Pseq(#[0, 1b, 1, 2b, 2, 3, 4b, 4, 5], inf)));

// using a fade time, the above changes are crossfaded
Pdef(\a).fadeTime = 2;

Pdef(\a, Pbind(\instrument, \Pdefhelp, \dur, 0.2, \degree, Pseq([0, 4, Prand([6, 8b],2)], inf)));

// ...

Pdef(\a).set(\detune, -50); // set environment
Pdef(\a).set(\detune, 0);

x.stop;
::

subsection::Pdef as EventStreamPlayer

code::
(
// load a synthdef
s.boot;
SynthDef("gpdef",
        { arg out=0, freq=440, sustain=0.05, amp=0.1, pan;
                var env;
                env = EnvGen.kr(Env.perc(0.01, sustain), doneAction:2) * amp;
                Out.ar(out, Pan2.ar(SinOsc.ar(freq, 0, env), pan))
        }).add;
)


Pdef(\x); // creates a Pdef with a default pattern.


Pdef(\x).play; // play it. A silent resting pattern is used.
Pdef(\y).play; // play a second one (automatically instantiated)


// assign various patterns to it:

Pdef(\x, Pbind(\dur, 0.25, \instrument, \gpdef));
Pdef(\x, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5b, 6], inf), \instrument, \gpdef));
Pdef(\x, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5b, 6]+1, inf), \instrument, \gpdef));
Pdef(\y, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5b, 6]-1, inf), \instrument, \gpdef));
Pdef(\y, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5b]-2, inf), \instrument, \gpdef));

// using fadeTime:

Pdef(\y).fadeTime = 8.0;
Pdef(\y, Pbind(\dur, 0.125, \degree, Pseq([3, 4, 5b, 6]+4.rand, inf), \instrument, \gpdef));
Pdef(\y, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5b, 6]-2, inf), \instrument, \gpdef));

(
Pdef(\x, Pbind(
                \dur, 1 / 6,
                \degree, Pseq([3, 4, Prand([8, 2, 3, 9, 10],1) - 5, 6]+1, inf),
                \instrument, \gpdef
                )
        );
)
(
Pdef(\x, Pbind(
                \dur, 0.25,
                \degree, Pseq([3, 4, Prand([8, 2, 3, 9, 10],1), 6], inf),
                \instrument, \gpdef)
        );
)
Pdef(\x).stop;

Pdef(\x).play;

// tempo change
TempoClock.default.tempo = 1.3;
Pdef(\y, Pbind(\dur, 0.25, \degree, Pseq([3, 4, 5, 6]+1, inf), \instrument, \gpdef));

// drop in ending patterns

Pdef(\x, Pbind(\dur, 0.25, \degree, Pseq([3, [7,4], 5, 6]-2), \instrument, \gpdef));
Pdef(\x, Pbind(\dur, 0.125, \degree, Pseq([3, [7,4], 5, 4]-3), \instrument, \gpdef));
Pdef(\x, Pbind(\dur, 0.35, \degree, Pseq([3, [7,4], 5, 4, 3]-3), \instrument, \gpdef));
Pdef(\x, Pbind(\dur, 0.25, \degree, Pshuf([3, [7,4], 5, 6]-2), \instrument, \gpdef));


// clear all.
Pdef(\x).clear;
Pdef(\y).clear;
TempoClock.default.tempo = 1.0;


// GUI example: see also
PdefAllGui(18);
::

subsection::Recursion

Pdefs can be used recursively under the condition that the stream call structure allows it. a structure like the following works:

code::
Pdef(\x, Pseq([Pbind(\instrument, \gpdef), Pdef(\x)], inf));
Pdef(\x).play;
::

but the following would crash, because code::.embedInStream:: is called recursively with no limit:

code::
// Pdef(\y, Pseq([Pdef(\y), Pbind(\instrument, \gpdef)], inf));
::

subsection::Quantizing and outset

When quantizing to a larger number of beats, the changes become very slow if one has to wait for the next beat. Providing an strong::outset:: quant value is a way to make the change so that it appears as if it had been done at the previous grid point already. The stream is fast forwarded to the current position relative to the quant grid. Providing a number larger than zero, the next possible quant point is used as outset.

For example, if quant is 32, and one has just missed the first beat when changing the pattern,
one has to wait for 32 beats until the change happens. Using an outset of 1, it is assumed that you had already
changed the pattern at the first beat, the stream is fast forwarded to the time it would be at now if you had done so. The new pattern is inserted at the next beat (outset=1).

quant can be: strong::[quant, phase, timingOffset, outset]::

note::
This fast forwarding might create a cpu peak if the pattern is very complex/fast or quant is very long. This is hard to avoid, so it simply has to be taken into account.
::

code::
(
Pdef(\x).quant_([8, 0, 0, 1]);
Pdef(\y).quant_([8, 0.5, 0, 1]); // phase: half a beat
Pdef(\x).play;
Pdef(\y).play;
)

Pdef(\x, Pbind(\degree, Pseq((0..7)+2, inf)));
Pdef(\y, Pbind(\degree, Pseq((0..7)-2, inf)));
Pdef(\x, Pbind(\degree, Pseq((0..7)+2, inf), \dur, 0.5));
Pdef(\y, Pbind(\degree, Pseq((0..7).scramble-2, inf), \dur, 0.25, \legato, 0.3));
Pdef(\x, Pbind(\degree, Pseq((0..7), inf)));

Pdef(\x, Pbind(\degree, Pseq([ 1, 5, 6, 7, 0, 3, 2, 4 ], inf), \dur, 1));
Pdef(\x, Pbind(\degree, Pseq([ 0, 2, 2, 4, 0, 4, 0, 4 ], inf), \dur, 1));

Pdef(\x).quant_([8, 1/3, 0, 1]); // phase: 1/6 beat relative to y
Pdef(\x, Pbind(\degree, Pseq([ 1, 1, 1, 7, 0, 2, 2, 4 ], inf), \legato, 0.1));
Pdef(\x, Pbind(\degree, Pseq([ 3, 3, 3, 4b ], inf), \legato, 0.1));
Pdef(\y, Pbind(\degree, Pseq((0..7).scramble-4, inf), \dur, 0.25, \legato, 0.3));




// some testing
(
var quant = #[8, 0, 0, 1]; // quantise to 8 beats, no phase, insert quant to 1 beat
Pdef(\x).quant_(quant);
Pdef(\x).play;
Routine { loop { 8.do { |i| ("uhr:"+i).postln; 1.wait } } }.play(quant:quant);
Pbind(\degree, Pseq((0..7), inf)).play(quant:quant);
)

Pdef(\x, Pbind(\degree, Pseq((0..7)+2, inf)).trace(\degree));
Pdef(\x, Pbind(\degree, Pseq((0..7), inf) + [0, 3]).trace(\degree));
Pdef(\x, Pbind(\degree, Pseq((0..7), inf) + [0, 6], \dur, 0.5).trace(\degree));


Pdef(\x).fadeTime = 8;

Pdef(\x, Pbind(\degree, Pseq((0..7), inf)).trace(\degree));
Pdef(\x, Pbind(\degree, Pseq((0..7).reverse, inf) + [0, 6], \dur, 0.5));

Pdef(\x).fadeTime = nil;
Pdef(\x).quant = 1;

Pdef(\x, Pbind(\degree, Pseq((0..7), inf)).trace(\degree));

Pdef(\x).quant = 8;
Pdef(\x, Pbind(\degree, Pseq((0..7), inf)).trace(\degree));
::

subsection::Update condition

In order to be able to switch to a new pattern under a certain link::#-condition::, the instance variable condition can be set to a function that returns a boolean. Value and a count index are passed to the function. The condition is always valid for the strong::next pattern:: inserted. For stuck conditions, the link::#-reset:: message can be used.

As counting up (such as emphasis::"every nth event, a swap can happen"::) is a common task, there is a method for this, called link::#-count::(n).

code::
Pdef(\x).play;
Pdef(\x).quant = 0; // we don't want quant here.
Pdef(\x, Pbind(\degree, Pseq((0..5), inf), \dur, 0.3)).condition_({ |val, i| i.postln % 6 == 0 });
Pdef(\x, Pbind(\degree, Pseq((0..7) + 5.rand, inf), \dur, 0.3)).condition_({ |val, i| (i % 8).postln == 0 });

// the above is equivalent to:
Pdef(\x, Pbind(\degree, Pseq((0..7) + 5.rand, inf), \dur, 0.3)).count(8);

// the value that is sent in is the event, so decisions can be made dependent on the event's fields
::

subsection::reset

code::
// reset to change immediately:
Pdef(\x).reset;
::