mirror of
https://github.com/Tonejs/Tone.js
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66 lines
No EOL
1.6 KiB
JavaScript
66 lines
No EOL
1.6 KiB
JavaScript
define(["Tone/core/Tone", "Tone/signal/Abs"], function(Tone){
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/**
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* @class Follow the envelope of the incoming signal
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* Note: due to the nature of low-pass filters,
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* there is some rippling which is proportional
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* to the smoothTime
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*
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* @constructor
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* @extends {Tone}
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* @param {Tone.Time=} [smoothTime = 0.1]
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*/
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Tone.Follower = function(smoothTime){
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Tone.call(this);
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//default values
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smoothTime = this.defaultArg(smoothTime, 0.1);
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/**
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* @type {Tone.Abs}
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* @private
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*/
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this._abs = new Tone.Abs();
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/**
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* the lowpass filter which smooths the input
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* @type {BiquadFilterNode}
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* @private
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*/
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this._filter = this.context.createBiquadFilter();
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this._filter.type = "lowpass";
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this._filter.Q.value = -10;
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//the connections
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this.chain(this.input, this._abs, this._filter, this.output);
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this.setSmoothTime(smoothTime);
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};
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Tone.extend(Tone.Follower);
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/**
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* set the amount of time it takes to reach the destination value
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*
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* @param {Tone.Time} smoothTime the amount of time it takes
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* to reach the destination value
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*/
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Tone.Follower.prototype.setSmoothTime = function(smoothTime){
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this._filter.frequency.value = this.secondsToFrequency(smoothTime * 2);
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};
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/**
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* dispose
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*/
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Tone.Follower.prototype.dispose = function(){
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this._filter.disconnect();
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this.input.disconnect();
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this.output.disconnect();
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this._abs.dispose();
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this._filter = null;
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this.input = null;
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this.output = null;
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this._abs = null;
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};
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return Tone.Follower;
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}); |