cleanup, WIP converting webaudio nodes to Tone objects

src/vocoder.js

@@ -1,68 +1,30 @@
 var Tone = require('tone');
 
-var modulatorNode = null;
-var carrierNode = null;
-var vocoding = false;
-
-var FILTER_QUALITY = 6;  // The Q value for the carrier and modulator filters
-
-// These are "placeholder" gain nodes - because the modulator and carrier will get swapped in
-// as they are loaded, it's easier to connect these nodes to all the bands, and the "real"
-// modulator & carrier AudioBufferSourceNodes connect to these.
-var modulatorInput = null;
-var carrierInput = null;
-
-var modulatorGain = null;
-var modulatorGainValue = 1.0;
-
-// noise node added to the carrier signal
-var noiseBuffer = null;
-var noiseNode = null;
-var noiseGain = null;
-var noiseGainValue = 0.2;
-
-// Carrier Synth oscillator stuff
-var oscillatorNode = null;
-var oscillatorType = 4;   // CUSTOM
-var oscillatorGain = null;
-var oscillatorGainValue = 1.0;
-var oscillatorDetuneValue = 0;
-var FOURIER_SIZE = 4096;
-var SAWTOOTHBOOST = 0.40;
-
-// These are the arrays of nodes - the "columns" across the frequency band "rows"
-var modFilterBands = null;    // tuned bandpass filters
-var modFilterPostGains = null;  // post-filter gains.
-var heterodynes = null;   // gain nodes used to multiply bandpass X sine
-var powers = null;      // gain nodes used to multiply prev out by itself
-var lpFilters = null;   // tuned LP filters to remove doubled copy of product
-var lpFilterPostGains = null;   // gain nodes for tuning input to waveshapers
-var carrierBands = null;  // tuned bandpass filters, same as modFilterBands but in carrier chain
-var carrierFilterPostGains = null;  // post-bandpass gain adjustment
-var carrierBandGains = null;  // these are the "control gains" driven by the lpFilters
-
-var vocoderBands;
-var numVocoderBands;
-
-var hpFilterGain = null;
-
-var outputGain;
-
 function Vocoder () {
     Tone.Effect.call(this);
 
-    outputGain = new Tone.Gain();
+    this.FILTER_QUALITY = 6;  // The Q value for the carrier and modulator filters
 
-    this.generateVocoderBands(55, 7040, 28);
+    this.modulatorInput = new Tone.Gain();
+    this.carrierInput = new Tone.Gain();
+    this.outputGain = new Tone.Gain();
+
+    this.oscillatorNode;
+
+    this.vocoderBands = this.generateVocoderBands(55, 7040, 10);
     this.initBandpassFilters();
     this.createCarrier();
 
-    this.effectSend.connect(modulatorInput);
+    this.effectSend.connect(this.modulatorInput);
-    outputGain.connect(this.effectReturn);
+    this.outputGain.connect(this.effectReturn);
 }
 
 Tone.extend(Vocoder, Tone.Effect);
 
+Vocoder.prototype.setCarrierOscFrequency = function (freq) {
+    this.oscillatorNode.frequency.rampTo(freq, 0.05);
+};
+
 // this function will algorithmically re-calculate vocoder bands, distributing evenly
 // from startFreq to endFreq, splitting evenly (logarhythmically) into a given numBands.
 // The function places this info into the vocoderBands and numVocoderBands variables.
@@ -73,7 +35,7 @@ Vocoder.prototype.generateVocoderBands = function (startFreq, endFreq, numBands)
     var centsPerBand = totalRangeInCents / numBands;
     var scale = Math.pow( 2, centsPerBand / 1200 );  // This is the scaling for successive bands
 
-    vocoderBands = [];
+    var vocoderBands = [];
     var currentFreq = startFreq;
 
     for (var i=0; i<numBands; i++) {
@@ -83,41 +45,20 @@ Vocoder.prototype.generateVocoderBands = function (startFreq, endFreq, numBands)
         currentFreq = currentFreq * scale;
     }
 
-    numVocoderBands = numBands;
+    return vocoderBands;
 };
 
 Vocoder.prototype.initBandpassFilters = function () {
-    // When this function is called, the carrierNode and modulatorAnalyser
-    // may not already be created.  Create placeholder nodes for them.
-    modulatorInput = Tone.context.createGain();
-    carrierInput = Tone.context.createGain();
 
-    if (modFilterBands == null)
+    var modFilterBands = new Array();           // tuned bandpass filters
-      modFilterBands = new Array();
+    var modFilterPostGains = new Array();       // post-filter gains.
-
+    var heterodynes = new Array();              // gain nodes used to multiply bandpass X sine
-    if (modFilterPostGains == null)
+    var powers = new Array();                   // gain nodes used to multiply prev out by itself
-      modFilterPostGains = new Array();
+    var lpFilters = new Array();                // tuned lowpass filters to remove doubled copy of product
-
+    var lpFilterPostGains = new Array();        // gain nodes for tuning input to waveshapers
-    if (heterodynes == null)
+    var carrierBands = new Array();             // tuned bandpass filters, same as modFilterBands but in carrier chain
-      heterodynes = new Array();
+    var carrierFilterPostGains = new Array();   // post-bandpass gain adjustment
-
+    var carrierBandGains = new Array();         // these are the "control gains" driven by the lpFilters
-    if (powers == null)
-      powers = new Array();
-
-    if (lpFilters == null)
-      lpFilters = new Array();
-
-    if (lpFilterPostGains == null)
-      lpFilterPostGains = new Array();
-
-    if (carrierBands == null)
-      carrierBands = new Array();
-
-    if (carrierFilterPostGains == null)
-      carrierFilterPostGains = new Array();
-
-    if (carrierBandGains == null)
-      carrierBandGains = new Array();
 
     var waveShaperCurve = new Float32Array(65536);
     // Populate with a "curve" that does an abs()
@@ -126,24 +67,22 @@ Vocoder.prototype.initBandpassFilters = function() {
 
     for (var i = 0; i < n2; ++i) {
         var x = i / n2;
-
         waveShaperCurve[n2 + i] = x;
         waveShaperCurve[n2 - i - 1] = x;
     }
 
     // Set up a high-pass filter to add back in the fricatives, etc.
-    // (this isn't used by default in the "production" version, as I hid the slider)
     var hpFilter = Tone.context.createBiquadFilter();
-    hpFilter.type = "highpass";
+    hpFilter.type = 'highpass';
-    hpFilter.frequency.value = 8000; // or use vocoderBands[numVocoderBands-1].frequency;
+    hpFilter.frequency.value = 8000;
     hpFilter.Q.value = 1; //  no peaking
-    modulatorInput.connect( hpFilter);
+    this.modulatorInput.connect( hpFilter);
 
-    hpFilterGain = Tone.context.createGain();
+    var hpFilterGain = Tone.context.createGain();
-    hpFilterGain.gain.value = 0.0;
+    hpFilterGain.gain.value = 1.0;
 
     hpFilter.connect(hpFilterGain);
-    hpFilterGain.connect( outputGain );
+    hpFilterGain.connect(this.outputGain);
 
     //clear the arrays
     modFilterBands.length = 0;
@@ -157,26 +96,27 @@ Vocoder.prototype.initBandpassFilters = function() {
     carrierBandGains.length = 0;
 
     var rectifierCurve = new Float32Array(65536);
-    for (var i=-32768; i<32768; i++)
+    for (i=-32768; i<32768; i++) {
         rectifierCurve[i+32768] = ((i>0)?i:-i)/32768;
+    }
 
-    for (var i=0; i<numVocoderBands; i++) {
+    for (i=0; i<this.vocoderBands.length; i++) {
         // CREATE THE MODULATOR CHAIN
         // create the bandpass filter in the modulator chain
         var modulatorFilter = Tone.context.createBiquadFilter();
-      modulatorFilter.type = "bandpass";  // Bandpass filter
+        modulatorFilter.type = 'bandpass';  // Bandpass filter
-      modulatorFilter.frequency.value = vocoderBands[i].frequency;
+        modulatorFilter.frequency.value = this.vocoderBands[i].frequency;
-      modulatorFilter.Q.value = FILTER_QUALITY; //  initial quality
+        modulatorFilter.Q.value = this.FILTER_QUALITY; //  initial quality
-      modulatorInput.connect(modulatorFilter);
+        this.modulatorInput.connect(modulatorFilter);
         modFilterBands.push(modulatorFilter);
 
         // Now, create a second bandpass filter tuned to the same frequency -
         // this turns our second-order filter into a 4th-order filter,
         // which has a steeper rolloff/octave
         var secondModulatorFilter = Tone.context.createBiquadFilter();
-      secondModulatorFilter.type = "bandpass";  // Bandpass filter
+        secondModulatorFilter.type = 'bandpass';  // Bandpass filter
-      secondModulatorFilter.frequency.value = vocoderBands[i].frequency;
+        secondModulatorFilter.frequency.value = this.vocoderBands[i].frequency;
-      secondModulatorFilter.Q.value = FILTER_QUALITY; //  initial quality
+        secondModulatorFilter.Q.value = this.FILTER_QUALITY; //  initial quality
         modulatorFilter.chainedFilter = secondModulatorFilter;
         modulatorFilter.connect(secondModulatorFilter);
 
@@ -188,7 +128,7 @@ Vocoder.prototype.initBandpassFilters = function() {
 
         // Create the sine oscillator for the heterodyne
         var heterodyneOscillator = Tone.context.createOscillator();
-      heterodyneOscillator.frequency.value = vocoderBands[i].frequency;
+        heterodyneOscillator.frequency.value = this.vocoderBands[i].frequency;
 
         heterodyneOscillator.start(0);
 
@@ -229,17 +169,17 @@ Vocoder.prototype.initBandpassFilters = function() {
 
         // Create the bandpass filter in the carrier chain
         var carrierFilter = Tone.context.createBiquadFilter();
-      carrierFilter.type = "bandpass";
+        carrierFilter.type = 'bandpass';
-      carrierFilter.frequency.value = vocoderBands[i].frequency;
+        carrierFilter.frequency.value = this.vocoderBands[i].frequency;
-      carrierFilter.Q.value = FILTER_QUALITY;
+        carrierFilter.Q.value = this.FILTER_QUALITY;
         carrierBands.push(carrierFilter);
-      carrierInput.connect(carrierFilter);
+        this.carrierInput.connect(carrierFilter);
 
         // We want our carrier filters to be 4th-order filter too.
         var secondCarrierFilter = Tone.context.createBiquadFilter();
-      secondCarrierFilter.type = "bandpass";  // Bandpass filter
+        secondCarrierFilter.type = 'bandpass';  // Bandpass filter
-      secondCarrierFilter.frequency.value = vocoderBands[i].frequency;
+        secondCarrierFilter.frequency.value = this.vocoderBands[i].frequency;
-      secondCarrierFilter.Q.value = FILTER_QUALITY; //  initial quality
+        secondCarrierFilter.Q.value = this.FILTER_QUALITY; //  initial quality
         carrierFilter.chainedFilter = secondCarrierFilter;
         carrierFilter.connect(secondCarrierFilter);
 
@@ -255,18 +195,17 @@ Vocoder.prototype.initBandpassFilters = function() {
         bandGain.gain.value = 0.0;  // audio-rate inputs are summed with initial intrinsic value
         waveshaper.connect(bandGain.gain);  // connect the lp controller
 
-      bandGain.connect(outputGain);
+        bandGain.connect(this.outputGain);
     }
 };
 
 Vocoder.prototype.createCarrier = function () {
-    oscillatorNode = new Tone.Oscillator(110, 'sawtooth8').start();
+    this.oscillatorNode = new Tone.Oscillator('C3', 'sawtooth').start();
-    oscillatorNode.connect(carrierInput);
+    this.oscillatorNode.connect(this.carrierInput);
 
-    noiseNode = new Tone.Noise('white').start();
+    var noiseNode = new Tone.Noise('white').start();
-    noiseGain = new Tone.Gain(noiseGainValue);
+    noiseNode.volume.value = -12;
-    noiseNode.connect(noiseGain);
+    noiseNode.connect(this.carrierInput);
-    noiseGain.connect(carrierInput);
+};
-  }
 
 module.exports = Vocoder;