rsc3/doc-schelp/HelpSource/Classes/LinExp.schelp

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class:: LinExp
summary:: Map a linear range to an exponential range
related:: Classes/LinLin
categories:: UGens>Maths
Description::
Converts a linear range of values to an exponential range of values.
classmethods::
method::ar, kr
argument::in
The input signal to convert.
argument::srclo
Lower limit of input range.
argument::srchi
Upper limit of input range.
argument::dstlo
Lower limit of output range.
argument::dsthi
Upper limit of output range.
discussion::
The code::dstlo:: and code::dsthi:: arguments
must be nonzero and have the same sign.
Examples::
code::
// compare:
(
{
var mod = SinOsc.kr(Line.kr(1, 10, 10));
SinOsc.ar(mod * 400 + 500) * 0.1
}.play;
)
(
{
var mod = SinOsc.kr(Line.kr(1, 10, 10));
SinOsc.ar(LinExp.kr(mod, -1,1, 100, 900)) * 0.1
}.play;
)
// modulating destination values.
(
{
var mod = LFNoise2.ar(80);
SinOsc.ar(LinExp.ar(mod, -1,1, MouseX.kr(200, 8000, 1), MouseY.kr(200, 8000, 1))) * 0.1
}.play;
)
::
code::linexp:: and code::exprange:: can be used to create a LinExp implicitly from a ugen, mapping its output values from linear range to an exponential one. The rate is derived from the ugen.
code::
// linexp
(
{
var mod = LFNoise2.ar(80);
SinOsc.ar(mod.linexp(-1,1, MouseX.kr(200, 8000, 1), MouseY.kr(200, 8000, 1))) * 0.1
}.play;
)
// exprange
(
{
var mod = LFNoise2.ar(80).exprange(MouseX.kr(200, 8000, 1), MouseY.kr(200, 8000, 1));
SinOsc.ar(mod) * 0.1
}.play;
)
::