Audio: Move to let/const.

src/audio/Audio.js

@@ -112,7 +112,7 @@ Audio.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 		this._startedAt = this.context.currentTime + delay;
 
-		var source = this.context.createBufferSource();
+		const source = this.context.createBufferSource();
 		source.buffer = this.buffer;
 		source.loop = this.loop;
 		source.loopStart = this.loopStart;
@@ -190,7 +190,7 @@ Audio.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 			this.source.connect( this.filters[ 0 ] );
 
-			for ( var i = 1, l = this.filters.length; i < l; i ++ ) {
+			for ( let i = 1, l = this.filters.length; i < l; i ++ ) {
 
 				this.filters[ i - 1 ].connect( this.filters[ i ] );
 
@@ -214,7 +214,7 @@ Audio.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 			this.source.disconnect( this.filters[ 0 ] );
 
-			for ( var i = 1, l = this.filters.length; i < l; i ++ ) {
+			for ( let i = 1, l = this.filters.length; i < l; i ++ ) {
 
 				this.filters[ i - 1 ].disconnect( this.filters[ i ] );
 

src/audio/AudioAnalyser.js

@@ -25,9 +25,10 @@ Object.assign( AudioAnalyser.prototype, {
 
 	getAverageFrequency: function () {
 
-		var value = 0, data = this.getFrequencyData();
+		let value = 0;
+		const data = this.getFrequencyData();
 
-		for ( var i = 0; i < data.length; i ++ ) {
+		for ( let i = 0; i < data.length; i ++ ) {
 
 			value += data[ i ];
 

src/audio/AudioContext.js

@@ -2,7 +2,7 @@
  * @author mrdoob / http://mrdoob.com/
  */
 
-var _context;
+let _context;
 
 var AudioContext = {
 

src/audio/AudioListener.js

@@ -8,10 +8,10 @@ import { Clock } from '../core/Clock.js';
 import { Object3D } from '../core/Object3D.js';
 import { AudioContext } from './AudioContext.js';
 
-var _position = new Vector3();
-var _quaternion = new Quaternion();
-var _scale = new Vector3();
-var _orientation = new Vector3();
+const _position = new Vector3();
+const _quaternion = new Quaternion();
+const _scale = new Vector3();
+const _orientation = new Vector3();
 
 function AudioListener() {
 
@@ -104,8 +104,8 @@ AudioListener.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 		Object3D.prototype.updateMatrixWorld.call( this, force );
 
-		var listener = this.context.listener;
-		var up = this.up;
+		const listener = this.context.listener;
+		const up = this.up;
 
 		this.timeDelta = this._clock.getDelta();
 
@@ -117,7 +117,7 @@ AudioListener.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 			// code path for Chrome (see #14393)
 
-			var endTime = this.context.currentTime + this.timeDelta;
+			const endTime = this.context.currentTime + this.timeDelta;
 
 			listener.positionX.linearRampToValueAtTime( _position.x, endTime );
 			listener.positionY.linearRampToValueAtTime( _position.y, endTime );

src/audio/PositionalAudio.js

@@ -7,10 +7,10 @@ import { Quaternion } from '../math/Quaternion.js';
 import { Audio } from './Audio.js';
 import { Object3D } from '../core/Object3D.js';
 
-var _position = new Vector3();
-var _quaternion = new Quaternion();
-var _scale = new Vector3();
-var _orientation = new Vector3();
+const _position = new Vector3();
+const _quaternion = new Quaternion();
+const _scale = new Vector3();
+const _orientation = new Vector3();
 
 function PositionalAudio( listener ) {
 
@@ -108,13 +108,13 @@ PositionalAudio.prototype = Object.assign( Object.create( Audio.prototype ), {
 
 		_orientation.set( 0, 0, 1 ).applyQuaternion( _quaternion );
 
-		var panner = this.panner;
+		const panner = this.panner;
 
 		if ( panner.positionX ) {
 
 			// code path for Chrome and Firefox (see #14393)
 
-			var endTime = this.context.currentTime + this.listener.timeDelta;
+			const endTime = this.context.currentTime + this.listener.timeDelta;
 
 			panner.positionX.linearRampToValueAtTime( _position.x, endTime );
 			panner.positionY.linearRampToValueAtTime( _position.y, endTime );