ControlSpec specification for a control input


superclass: Spec


The original, and most common spec.  (see Spec )


ControlSpec.new( minval, maxval, warp, step, default,units);


A ControlSpec is used by GUI sliders and knobs to specify the range and curve of the controls.  They also have widespread use in the crucial library to specify Instr inputs and player outputs.  ControlSpec may be used in many ways to map from linear 0..1 range to your desired range and back.


The most common way to create one is by 


anObject.asSpec


// array is used as arguments to ControlSpec.new( minval, maxval, warp, step, default)

[300,3000,\exponential,100].asSpec.dump

Instance of ControlSpec {    (0313FC08, gc=00, fmt=00, flg=00, set=03)

  instance variables [6]

    minval : Integer 300

    maxval : Integer 3000

    warp : Symbol 'exponential'

    step : Integer 100

    default : Integer 300

}


// partially specified ...

[-48,48].asSpec.dump

Instance of ControlSpec {    (0313FF18, gc=00, fmt=00, flg=00, set=03)

  instance variables [6]

    minval : Integer -48

    maxval : Integer 48

    warp : Symbol 'linear'

    step : Float 0

    default : Integer -48

}


// a Symbol

\freq.asSpec.dump

Instance of ControlSpec {    (180F4910, gc=3C, fmt=00, flg=00, set=03)

  instance variables [8]

    minval : Integer 20

    maxval : Integer 20000

    warp : instance of ExponentialWarp (17FEDB30, size=1, set=1)

    step : Integer 0

    default : Integer 440

    units : " Hz"

    clipLo : Integer 20

    clipHi : Integer 20000

}

In this case \freq was looked up in the Specs dictionary.  See Spec

Some common mappings are initialized in ControlSpec.initClass

and also (for the moment) in Crucial-initClass


// nil becomes a default ControlSpec

nil.asSpec.dump

Instance of ControlSpec {    (0313FF18, gc=00, fmt=00, flg=00, set=03)

  instance variables [6]

    minval : Float 0

    maxval : Float 1

    warp : Symbol 'linear'

    step : Float 0

    default : Float 0

}





constrain (value)

clips and rounds the value to within the spec

map (value)

maps a value from [0..1] to spec range


unmap (value)

maps a value from the spec range to [0..1]





// example


// make a frquency spec with an exponential range from 20 to 20000, 

// give it a rounding of 30 (Hz)

a = \freq.asSpec;

a.step = 100;


// equivalent:

a = [20, 20000, 'exp', 100, 440].asSpec;

a.dump;


a.constrain(800); // make sure it is in range and round it.

a.constrain(803); // make sure it is in range and round it.


a.map(0.5);

a.map(0.0); // returns min

a.map(1.5); // exceeds the area: clip, returns max


a.unmap(4000);

a.unmap(22.0);

// using spec for sliders:

(

var w, c, d;

w = GUI.window.new("control", Rect(128, 64, 340, 160));

w.front;

c = GUI.slider.new(w, Rect(10, 10, 300, 30));

d = GUI.staticText.new(w, Rect(10, 40, 300, 30));

c.action = { 

d.string = "unmapped value"

+ c.value.round(0.01) 

+ "......" 

+ "mapped value" 

+ a.map(c.value)

};

)


ControlSpec-map can also be used to map ugens 

(

var spec;

spec = [ 100,18000,\exp].asSpec;

{

var freq,osc;

osc = SinOsc.kr(0.1).range(0,1);

freq = spec.map(  osc );

freq.dump;// BinaryOpUGen


SinOsc.ar(

  freq

)

}.play


)