Add ability to pan sounds

src/sound/BaseSound.js

@@ -128,7 +128,8 @@ var BaseSound = new Class({
             detune: 0,
             seek: 0,
             loop: false,
-            delay: 0
+            delay: 0,
+            pan: 0
 
         };
 
@@ -217,7 +218,8 @@ var BaseSound = new Class({
                 detune: 0,
                 seek: 0,
                 loop: false,
-                delay: 0
+                delay: 0,
+                pan: 0
             }
         }, marker);
 
@@ -418,6 +420,7 @@ var BaseSound = new Class({
         this.rate = this.currentConfig.rate;
         this.detune = this.currentConfig.detune;
         this.loop = this.currentConfig.loop;
+        this.pan = this.currentConfig.pan;
     },
 
     /**

src/sound/events/PAN_EVENT.js

@@ -0,0 +1,27 @@
+/**
+ * @author       pi-kei
+ * @copyright    2020 Photon Storm Ltd.
+ * @license      {@link https://opensource.org/licenses/MIT|MIT License}
+ */
+
+/**
+ * The Sound Pan Event.
+ *
+ * This event is dispatched by both Web Audio and HTML5 Audio Sound objects when their pan changes.
+ *
+ * Listen to it from a Sound instance using `Sound.on('pan', listener)`, i.e.:
+ *
+ * ```javascript
+ * var sound = this.sound.add('key');
+ * sound.on('pan', listener);
+ * sound.play();
+ * sound.setPan(0.5);
+ * ```
+ *
+ * @event Phaser.Sound.Events#PAN
+ * @since 3.0.0
+ *
+ * @param {(Phaser.Sound.WebAudioSound|Phaser.Sound.HTML5AudioSound)} sound - A reference to the Sound that emitted the event.
+ * @param {number} pan - The new pan of the Sound.
+ */
+module.exports = 'pan';

src/sound/events/index.js

@@ -32,6 +32,7 @@ module.exports = {
     STOP_ALL: require('./STOP_ALL_EVENT'),
     STOP: require('./STOP_EVENT'),
     UNLOCKED: require('./UNLOCKED_EVENT'),
-    VOLUME: require('./VOLUME_EVENT')
+    VOLUME: require('./VOLUME_EVENT'),
+    PAN: require('./PAN_EVENT')
 
 };

src/sound/html5/HTML5AudioSound.js

@@ -916,6 +916,49 @@ var HTML5AudioSound = new Class({
     {
         this.loop = value;
 
+        return this;
+    },
+
+    /**
+     * Gets or sets the pan of this sound, a value between -1 (full left pan) and 1 (full right pan).
+     * Has no effect on HTML5 Audio Sound.
+     *
+     * @name Phaser.Sound.HTML5AudioSound#pan
+     * @type {number}
+     * @default 0
+     * @fires Phaser.Sound.Events#PAN
+     * @since 3.0.0
+     */
+    pan: {
+
+        get: function ()
+        {
+            return this.currentConfig.pan;
+        },
+
+        set: function (value)
+        {
+            this.currentConfig.pan = value;
+
+            this.emit(Events.PAN, this, value);
+        }
+    },
+
+    /**
+     * Sets the pan of this Sound. Has no effect on HTML5 Audio Sound.
+     *
+     * @method Phaser.Sound.HTML5AudioSound#setPan
+     * @fires Phaser.Sound.Events#PAN
+     * @since 3.4.0
+     *
+     * @param {number} value - The pan of the sound.
+     *
+     * @return {Phaser.Sound.HTML5AudioSound} This Sound instance.
+     */
+    setPan: function (value)
+    {
+        this.pan = value;
+
         return this;
     }
 

src/sound/noaudio/NoAudioSound.js

@@ -70,7 +70,8 @@ var NoAudioSound = new Class({
             detune: 0,
             seek: 0,
             loop: false,
-            delay: 0
+            delay: 0,
+            pan: 0
         }, config);
 
         this.currentConfig = this.config;
@@ -80,6 +81,7 @@ var NoAudioSound = new Class({
         this.detune = 0;
         this.seek = 0;
         this.loop = false;
+        this.pan = 0;
         this.markers = {};
         this.currentMarker = null;
         this.pendingRemove = false;
@@ -178,7 +180,9 @@ var NoAudioSound = new Class({
 
     setSeek: returnThis,
 
-    setLoop: returnThis
+    setLoop: returnThis,
+
+    setPan: returnThis
 
 });
 

src/sound/typedefs/SoundConfig.js

@@ -11,4 +11,5 @@
  * @property {number} [seek=0] - Position of playback for this sound, in seconds.
  * @property {boolean} [loop=false] - Whether or not the sound or current sound marker should loop.
  * @property {number} [delay=0] - Time, in seconds, that should elapse before the sound actually starts its playback.
+ * @property {number} [pan=0] - A value between -1 (full left pan) and 1 (full right pan). 0 means no pan.
  */

src/sound/webaudio/WebAudioSound.js

@@ -91,6 +91,15 @@ var WebAudioSound = new Class({
          */
         this.volumeNode = manager.context.createGain();
 
+        /**
+         * Panner node responsible for controlling this sound's pan.
+         *
+         * @name Phaser.Sound.WebAudioSound#pannerNode
+         * @type {StereoPannerNode}
+         * @private
+         */
+        this.pannerNode = manager.context.createStereoPanner();
+
         /**
          * The time at which the sound should have started playback from the beginning.
          * Based on BaseAudioContext.currentTime value.
@@ -165,7 +174,9 @@ var WebAudioSound = new Class({
 
         this.muteNode.connect(this.volumeNode);
 
-        this.volumeNode.connect(manager.destination);
+        this.volumeNode.connect(this.pannerNode);
+
+        this.pannerNode.connect(manager.destination);
 
         this.duration = this.audioBuffer.duration;
 
@@ -493,6 +504,8 @@ var WebAudioSound = new Class({
         this.muteNode = null;
         this.volumeNode.disconnect();
         this.volumeNode = null;
+        this.pannerNode.disconnect();
+        this.pannerNode = null;
         this.rateUpdates.length = 0;
         this.rateUpdates = null;
     },
@@ -892,6 +905,49 @@ var WebAudioSound = new Class({
     {
         this.loop = value;
 
+        return this;
+    },
+
+    /**
+     * Gets or sets the pan of this sound, a value between -1 (full left pan) and 1 (full right pan).
+     *
+     * @name Phaser.Sound.WebAudioSound#pan
+     * @type {number}
+     * @default 0
+     * @fires Phaser.Sound.Events#PAN
+     * @since 3.0.0
+     */
+    pan: {
+
+        get: function ()
+        {
+            return this.pannerNode.pan.value;
+        },
+
+        set: function (value)
+        {
+            this.currentConfig.pan = value;
+            this.pannerNode.pan.setValueAtTime(value, this.manager.context.currentTime);
+
+            this.emit(Events.PAN, this, value);
+        }
+    },
+
+    /**
+     * Sets the pan of this Sound.
+     *
+     * @method Phaser.Sound.WebAudioSound#setPan
+     * @fires Phaser.Sound.Events#PAN
+     * @since 3.4.0
+     *
+     * @param {number} value - The pan of the sound.
+     *
+     * @return {Phaser.Sound.WebAudioSound} This Sound instance.
+     */
+    setPan: function (value)
+    {
+        this.pan = value;
+
         return this;
     }