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

118 lines
1.7 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{Index}
Index into a table with a signal@section{related}
Classes/WrapIndex, Classes/Shaper
@section{categories}
UGens>Buffer
@section{description}
Index into a table with a signal.
The input signal value is truncated to an integer value and used as an
index into the table. Out-of-range index values are clipped to the valid
range.
@section{classmethods}
@section{method}
ar, kr
@section{argument}
bufnum
Index of the buffer.
@section{argument}
in
The input signal.
@section{argument}
mul
Output will be multiplied by this value.
@section{argument}
add
This value will be added to the output.
@section{Examples}
@racketblock[
// indexing into a fixed table
(
{
SinOsc.ar(
Index.kr(
LocalBuf.newFrom([ 200, 300, 400, 500, 600, 800 ]),
LFSaw.kr(2.0).range(0, 7)
),
0,
0.5
)
}.play;
)
// with mouse control
(
{
SinOsc.ar(
Index.kr(
LocalBuf.newFrom([ 200, 300, 400, 500, 600, 800 ]),
MouseX.kr(0, 7)
),
0,
0.5
)
}.play;
)
(
// indexing into a changeable table
s = Server.local;
t = [ 200, 300, 400, 500, 600, 800 ];
b = Buffer(s, t.size, 1);
// alloc and set the values
s.listSendMsg( b.allocMsg( b.setnMsg(0, t) ).postln );
SynthDef(\help_Index, { arg out = 0, i_bufnum = 0;
Out.ar(0,
SinOsc.ar(
Index.kr(
i_bufnum,
LFSaw.kr(2).range(0, 7)
),
0,
0.5
)
)
}).play(s, [\i_bufnum, b]);
)
b.setn(*[ 200, 300, 400, 500, 600, 800 ].scramble.postln - 30);
(
SynthDef(\help_Index, { arg out=0,i_bufnum=0;
Out.ar(0,
SinOsc.ar(
Index.kr(
i_bufnum,
MouseX.kr(0, BufFrames.ir(i_bufnum))
),
0,
0.5
)
)
}).play(s, [\i_bufnum, b]);
)
b.free;
::
]