Replace ScriptProcessorNode in p5.SoundFile with AudioWorkletNode

Author: oshoham

lib/p5.sound.js

@@ -1,6 +1,7 @@
 const p5sound = require('master');
 const moduleSources = [
-  require('raw-loader!./recorderProcessor').default
+  require('raw-loader!./recorderProcessor').default,
+  require('raw-loader!./soundFileProcessor').default
 ];
 const ac = p5sound.audiocontext;
 

lib/p5.sound.js.map

@@ -1,3 +1,4 @@
 module.exports = {
-  recorderProcessor: 'recorder-processor'
+  recorderProcessor: 'recorder-processor',
+  soundFileProcessor: 'sound-file-processor'
 };

lib/p5.sound.min.js

@@ -0,0 +1,16 @@
+// import processor name via preval.require so that it's available as a value at compile time
+const processorNames = preval.require('./processorNames');
+
+class SoundFileProcessor extends AudioWorkletProcessor {
+  process(inputs) {
+    const input = inputs[0];
+    const inputChannel = input[0];
+    const position = inputChannel[inputChannel.length - 1] || 0;
+
+    this.port.postMessage({ name: 'position', position: position });
+
+    return true;
+  }
+}
+
+registerProcessor(processorNames.soundFileProcessor, SoundFileProcessor);

lib/p5.sound.min.js.map

@@ -7,6 +7,7 @@ define(function (require) {
   var ac = p5sound.audiocontext;
   var midiToFreq = require('helpers').midiToFreq;
   var convertToWav = require('helpers').convertToWav;
+  var processorNames = require('./audioWorklet/processorNames');
 
   /**
    *  <p>SoundFile object with a path to a file.</p>
@@ -94,7 +95,7 @@ define(function (require) {
     //  position of the most recently played sample
     this._lastPos = 0;
     this._counterNode = null;
-    this._scopeNode = null;
+    this._workletNode = null;
 
     // array of sources so that they can all be stopped!
     this.bufferSourceNodes = [];
@@ -1238,23 +1239,28 @@ define(function (require) {
     var now = ac.currentTime;
     var cNode = ac.createBufferSource();
 
-    // dispose of scope node if it already exists
-    if (self._scopeNode) {
-      self._scopeNode.disconnect();
-      self._scopeNode.removeEventListener('audioprocess', self._onAudioProcess);
-      delete self._scopeNode;
+    // dispose of worklet node if it already exists
+    if (self._workletNode) {
+      self._workletNode.disconnect();
+      delete self._workletNode;
     }
-    self._scopeNode = ac.createScriptProcessor( 256, 1, 1 );
+    self._workletNode = new AudioWorkletNode(ac, processorNames.soundFileProcessor);
+    self._workletNode.port.onmessage = function(event) {
+      if (event.data.name === 'position') {
+        this._lastPos = event.data.position;
+
+        // do any callbacks that have been scheduled
+        this._onTimeUpdate(self._lastPos);
+      }
+    }.bind(self);
 
     // create counter buffer of the same length as self.buffer
     cNode.buffer = _createCounterBuffer( self.buffer );
 
     cNode.playbackRate.setValueAtTime(self.playbackRate, now);
 
-    cNode.connect( self._scopeNode );
-    self._scopeNode.connect( p5.soundOut._silentNode );
-
-    self._scopeNode.addEventListener('audioprocess', self._onAudioProcess);
+    cNode.connect(self._workletNode);
+    self._workletNode.connect(p5.soundOut._silentNode);
 
     return cNode;
   };