53 lines
1.2 KiB
Text
53 lines
1.2 KiB
Text
|
#lang scribble/manual
|
||
|
|
@(require (for-label racket))
|
||
|
|
|
||
|
|
@title{Warp}
|
||
|
|
specification of a shape for a mapping of numerical input@section{related}
|
||
|
|
Classes/ControlSpec, Classes/Spec
|
||
|
|
@section{categories}
|
||
|
|
Control, Spec
|
||
|
|
|
||
|
|
@section{description}
|
||
|
|
|
||
|
|
The subclasses of Warp specify translations from input (a number) to an output (another number). This is an abstract class - already available shapes are emphasis::linear, exponential, sine, cosine, decibel, curve:: (this is similar to the curves in envelopes, see also link::Classes/Env::).
|
||
|
|
|
||
|
|
Warps are internally created by link::Classes/ControlSpec::. Usually they are created by the message strong::asWarp::, understood by symbols and numbers. A warp has a link::Classes/Spec:: to specify a certain range of input and output values.
|
||
|
|
|
||
|
|
|
||
|
|
@racketblock[
|
||
|
|
// create a new warp:
|
||
|
|
a = \exp.asWarp;
|
||
|
|
a = -4.asWarp; // a curve warp;
|
||
|
|
::
|
||
|
|
|
||
|
|
]
|
||
|
|
@section{ClassMethods}
|
||
|
|
|
||
|
|
|
||
|
|
@section{private}
|
||
|
|
initClass
|
||
|
|
|
||
|
|
@section{InstanceMethods}
|
||
|
|
|
||
|
|
|
||
|
|
@section{method}
|
||
|
|
map
|
||
|
|
Maps and constrains a strong::value:: between 0 and 1 to the output domain.
|
||
|
|
|
||
|
|
@section{method}
|
||
|
|
unmap
|
||
|
|
in the output domain to a value in the range between 0 and 1.
|
||
|
|
|
||
|
|
|
||
|
|
@racketblock[
|
||
|
|
g = -3.asWarp;
|
||
|
|
g.map(0.5);
|
||
|
|
g.unmap(0.9);
|
||
|
|
|
||
|
|
// fore and back translation should be identical:
|
||
|
|
g.unmap(g.map(0.5));
|
||
|
|
::
|
||
|
|
]
|
||
|
|
|
||
|
|
|