1class:: PlazyEnvirN
2summary:: instantiate new patterns from a function and multichannel expand them
3related:: Classes/Plazy, Classes/PlazyEnvir, Classes/Pfunc
4categories:: Streams-Patterns-Events>Patterns>Function
5
6description::
7
8Evaluates a function that returns a pattern and embeds it in a stream.
9list::
10## In difference to link::Classes/Plazy::, the function is evaluated using the environment passed in by the stream.
11## In difference to link::Classes/PlazyEnvir::, PlayzEnvirN expands to strong::multiple parallel patterns:: if the function arguments receive multiple channels. This works only with event streams.
12::
13
14ClassMethods::
15
16method::new
17
18argument::func
19A link::Classes/Function:: that returns a pattern or any other valid pattern input.
20
21code::
22(
23f = { arg g=0, h=0, dur=1;
24	Pbind(\degree, Pseq([g, g, h, g, h], 2), \dur, Pseries(dur, 0.1))
25};
26// compare:
27a = Pchain(PlazyEnvirN(f), (g: [1, 2], h: 3, dur:0.2)).trace(\degree).asStream;
28c = Pchain(Plazy(f), (g: [1, 2], h: 3, dur:0.2)).asStream;
29)
30
31a.nextN(4);
32c.nextN(4); // no degrees, because stream ends
33::
34
35
36Examples::
37
38code::
39(
40SynthDef(\help_sinegrain,
41	{ arg out=0, freq=440, sustain=0.05, pan=0;
42		var env;
43		env = EnvGen.kr(Env.perc(0.01, sustain, 0.2), doneAction: Done.freeSelf);
44		Out.ar(out, Pan2.ar(SinOsc.ar(freq, 0, env), pan))
45	}).add;
46
47a = PlazyEnvirN({ arg g=0, h=0, dur=1;
48	postf("g: %, h: %, dur: %\n", g, h, dur);
49
50	Pbind(
51		\instrument, \help_sinegrain,
52		\dur, dur,
53		\degree, Pseq([g, g, h, g, h], 2)
54	)
55});
56)
57
58// different variants
59(a <> (g: 0, h: 3, dur:0.2)).play; // single stream
60(a <> (g: [0, 4], h: [3, -1], dur:0.2)).play; // same durations, two streams
61(a <> (g: [0, 4], h: [3, -1], dur: [0.2, 0.3])).play; // different durations, two streams
62::
63
64For more about the composition operator code::<>:: see: link::Classes/Pchain::.
65