improved audio graph

Author: chrisweb

source/library/audio.ts

@@ -3,10 +3,36 @@
 
 import { PlayerError, IPlayerError } from './error';
 
+// Note to self: AudioGraph documentation
+// https://developer.mozilla.org/en-US/docs/Web/API/AudioNode
+
 export interface IAudioGraph {
+    // https://developer.mozilla.org/en-US/docs/Web/API/GainNode
     gainNode: GainNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/PannerNode
     pannerNode?: PannerNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/StereoPannerNode
     stereoPannerNode?: StereoPannerNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/DelayNode
+    delayNode?: DelayNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/ScriptProcessorNode
+    scriptProcessorNode?: ScriptProcessorNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/AnalyserNode
+    analyserNode?: AnalyserNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/BiquadFilterNode
+    biquadFilterNode?: BiquadFilterNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/ChannelMergerNode
+    channelMergeNode?: ChannelMergerNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/ChannelSplitterNode
+    channelSplitterNode?: ChannelSplitterNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/ConvolverNode
+    convolverNode?: ConvolverNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/DynamicsCompressorNode
+    dynamicCompressorNode?: DynamicsCompressorNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/OscillatorNode
+    oscillatorNode?: OscillatorNode;
+    // https://developer.mozilla.org/en-US/docs/Web/API/WaveShaperNode
+    waveShaperNode?: WaveShaperNode;
 }
 
 export interface IAudioGraphOptions {
@@ -22,13 +48,16 @@ export class PlayerAudio {
 
     protected _context: AudioContext;
     protected _contextState: string;
-    protected _audioGraph: IAudioGraph | null;
+    protected _audioGraph: IAudioGraph | null = null;
 
-    constructor() {
+    constructor(customAudioGraph?: IAudioGraph) {
 
         // initial context state is still "closed"
         this._contextState = 'closed';
-        this._audioGraph = null;
+
+        if (customAudioGraph !== undefined) {
+            this._audioGraph = customAudioGraph;
+        }
 
         // TODO: to speed up things would it be better to create a context in the constructor?
         // and suspend the context upon creating it until it gets used?
@@ -69,7 +98,7 @@ export class PlayerAudio {
 
                 this._context = audioContext;
 
-                this._createAudioGraph();
+                this._connectAudioGraphGainToDestination();
 
                 resolve();
 
@@ -135,27 +164,26 @@ export class PlayerAudio {
 
     }
 
-    protected _createAudioGraph() {
+    protected _connectAudioGraphGainToDestination() {
 
-        // https://developer.mozilla.org/en-US/docs/Web/API/GainNode
+        if (this._audioGraph === null) {
 
-        let audioGraph = {
-            gainNode: this._context.createGain()
-        };
+            this._audioGraph = {
+                gainNode: this._context.createGain()
+            }
 
-        // connect the gain node to the destination (speakers)
-        audioGraph.gainNode.connect(this._context.destination);
+        }
 
-        this._audioGraph = audioGraph;
+        // connect the gain node to the destination (speakers)
+        // https://developer.mozilla.org/en-US/docs/Web/API/AudioDestinationNode
+        this._audioGraph.gainNode.connect(this._context.destination);
 
     }
 
     public setAudioGraph(audioGraph: IAudioGraph) {
 
         if (this._audioGraph !== null) {
-
             this._destroyAudioGraph();
-
         }
 
         this._audioGraph = audioGraph;
@@ -197,7 +225,7 @@ export class PlayerAudio {
 
     }
 
-    public connectSourceNodeToGraph(sourceNode: AudioBufferSourceNode) {
+    public connectSourceNodeToGraphGainNode(sourceNode: AudioBufferSourceNode) {
 
         sourceNode.connect(this._audioGraph.gainNode);
 

source/library/core.ts

@@ -2,7 +2,7 @@
 'use strict';
 
 import { PlayerSound, ISound, ISoundAttributes, ISoundSource } from './sound';
-import { PlayerAudio } from './audio';
+import { PlayerAudio, IAudioGraph } from './audio';
 import { PlayerRequest } from './request';
 import { PlayerError, IPlayerError } from './error';
 
@@ -12,6 +12,7 @@ export interface ICoreOptions {
     soundsBaseUrl?: string;
     playingProgressIntervalTime?: number;
     playNextOnEnded?: boolean;
+    audioGraph?: IAudioGraph;
 }
 
 export class PlayerCore {
@@ -31,11 +32,13 @@ export class PlayerCore {
     // playing progress time interval
     protected _playingProgressIntervalTime: number;
     // playing progress timeoutID
-    protected _playingTimeoutID: number | null;
+    protected _playingTimeoutID: number | null = null;
     // when a song finishes, automatically play the next one
     protected _playNextOnEnded: boolean;
     // do we start over gain at the end of the queue
     protected _loopQueue: boolean;
+    // a custon audioGraph created by the user
+    protected _customAudioGraph: IAudioGraph | null = null;
 
     // constants
     readonly WHERE_IN_QUEUE_AT_END: string = 'append';
@@ -67,6 +70,10 @@ export class PlayerCore {
         this._playNextOnEnded = options.playNextOnEnded;
         this._loopQueue = options.loopQueue;
 
+        if (typeof options.audioGraph !== 'undefined') {
+            this._customAudioGraph = options.audioGraph;
+        }
+
         this._initialize();
 
     }
@@ -90,7 +97,7 @@ export class PlayerCore {
         }
 
         // player audio library instance
-        this._playerAudio = new PlayerAudio();
+        this._playerAudio = new PlayerAudio(this._customAudioGraph);
 
     }
 
@@ -423,7 +430,7 @@ export class PlayerCore {
             sound.startTime = sourceNode.context.currentTime;
 
             // connect the source to the graph (destination)
-            this._playerAudio.connectSourceNodeToGraph(sourceNode);
+            this._playerAudio.connectSourceNodeToGraphGainNode(sourceNode);
 
             // start playback
             // start(when, offset, duration)
@@ -778,4 +785,20 @@ export class PlayerCore {
 
     };
 
+    public setAudioGraph(customAudioGraph: IAudioGraph) {
+
+        this._playerAudio.setAudioGraph(customAudioGraph);
+
+        this._customAudioGraph = customAudioGraph;
+
+    }
+
+    public getAudioGraph(): IAudioGraph {
+
+        this._customAudioGraph = this._playerAudio.getAudioGraph();
+
+        return this._customAudioGraph;
+
+    }
+
 }