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

137 lines
2.8 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{BufRd}
Buffer reading oscillator.@section{related}
Classes/BufWr
@section{categories}
UGens>Buffer
@section{description}
Read the content of a buffer at an index.
In comparison to link::Classes/PlayBuf:: :
PlayBuf plays through the buffer by itself, BufRd only moves its read point by the phase input and
therefore has no pitch input. BufRd has variable interpolation.
@section{classmethods}
@section{private}
categories
@section{method}
ar, kr
@section{argument}
numChannels
Number of channels that the buffer will be. This must be a fixed
integer. The architecture of the SynthDef cannot change after it
is compiled.
@section{note}
If you supply a
@racketblock[bufnum:: of a buffer that has a
different ]
@racketblock[numChannels:: then you have specified to
the BufRd, it will post a warning and output the channels it can.
::
]
@section{argument}
bufnum
The index of the buffer to use.
@section{argument}
phase
Audio rate modulateable index into the buffer.
@section{Warning}
The phase argument only offers precision for addressing 2**24 samples (about 6.3 minutes at 44100Hz). ::
@section{argument}
loop
1 means true, 0 means false. This is modulateable.
@section{argument}
interpolation
1 means no interpolation, 2 is linear, 4 is cubic interpolation.
@section{instancemethods}
@section{private}
init, argNamesInputsOffset, checkInputs
@section{Examples}
@racketblock[
(
// read a whole sound into memory
s = Server.local;
// note: not *that* columbia, the first one
b = Buffer.read(s, Platform.resourceDir +/+ "sounds/a11wlk01.wav");
)
//use any AUDIO rate ugen as an index generator
{ BufRd.ar(1, b, SinOsc.ar(0.1) * BufFrames.ir(b)) }.play;
{ BufRd.ar(1, b, LFNoise1.ar(1) * BufFrames.ir(b)) }.play;
{ BufRd.ar(1, b, LFNoise1.ar(10) * BufFrames.ir(b)) }.play;
{ BufRd.ar(1, b, LFTri.ar(0.1) + LFTri.ar(0.23) * BufFrames.ir(b)) }.play;
// original duration
{ BufRd.ar(1, b, LFSaw.ar(BufDur.ir(b).reciprocal).range(0, BufFrames.ir(b)) ) }.play;
//use a phasor index into the file
{ BufRd.ar(1, b, Phasor.ar(0, BufRateScale.kr(b), 0, BufFrames.kr(b))) }.play;
//change rate and interpolation
(
x = { arg rate=1, inter=2;
BufRd.ar(1, b, Phasor.ar(0, BufRateScale.kr(b) * rate, 0, BufFrames.kr(b)), 1, inter)
}.play;
)
x.set(\rate, 0.9);
x.set(\rate, 0.6);
x.set(\inter, 1);
x.set(\inter, 0);
//write into the buffer with a BufWr
(
y = { arg rate=1;
var in;
in = SinOsc.ar(LFNoise1.kr(2, 300, 400), 0, 0.1);
BufWr.ar(in, b, Phasor.ar(0, BufRateScale.kr(b) * rate, 0, BufFrames.kr(b)));
0.0 //quiet
}.play;
)
//read it with a BufRd
(
x = { arg rate=1;
BufRd.ar(1, b, Phasor.ar(0, BufRateScale.kr(b) * rate, 0, BufFrames.kr(b)))
}.play;
)
x.set(\rate, 5);
y.set(\rate, 2.0.rand);
x.set(\rate, 2);
b.free
::
]