Proposed new features: filtering, distortion and convolution (reverb)

src/soundjs/AbstractSoundInstance.js

@@ -217,6 +217,20 @@ this.createjs = this.createjs || {};
 			set: this.setDistortionAmount
 		});
 
+		/**
+		 * The convolver buffer to use on the convolver node. This can be an audioBuffer or a filepath, and will be handled appropriately depending on which.
+		 * Note that convolver is not supported by HTML Audio.
+		 *
+		 * @property convolverBuffer
+		 * @type {String} || {AudioBuffer}
+		 * @default null
+		 */
+		this._convolverBuffer =  null;
+		Object.defineProperty(this, "convolverBuffer", {
+			get: this.getConvolverBuffer,
+			set: this.setConvolverBuffer
+		});
+
 		/**
 		 * Audio sprite property used to determine the starting offset.
 		 * @property startTime
@@ -735,6 +749,44 @@ this.createjs = this.createjs || {};
 		return this._distortionAmount;
 	};
 
+	/**
+	 * DEPRECATED, please use {{#crossLink "AbstractSoundInstance/convolverBuffer:property"}}{{/crossLink}} directly as a property
+	 *
+	 * @deprecated
+	 * @method setConvolverBuffer
+	 * @param {String} The filepath to an impulse response WAV || {AudioBuffer} The audio buffer to use as the convoler's buffer.
+	 * @return {AbstractSoundInstance} Returns reference to itself for chaining calls
+	 */
+	p.setConvolverBuffer = function (buffer) {
+		if (typeof buffer === 'string') {
+			//if a filepath is passed, must import it as an arraybuffer and decode
+			this._getConvolverBufferFromFilepath(buffer);
+		}
+		else {
+			if (typeof AudioBuffer !== 'undefined' && buffer instanceof AudioBuffer) {
+				//audio buffer is passed, set it directly
+				this._convolverBuffer = buffer;
+				this._updateConvolver();
+			}
+			else {
+				return false;
+			}
+		}
+		return this;
+	};
+
+	/**
+	 * DEPRECATED, please use {{#crossLink "AbstractSoundInstance/convolverBuffer:property"}}{{/crossLink}} directly as a property
+	 *
+	 * @deprecated
+	 * @method getConvolverBuffer
+	 * @return {AudioBuffer} The audio buffer being used as the convolver's buffer.
+	 */
+	p.getConvolverBuffer = function () {
+		return this._convolverBuffer;
+	};
+
+
 	/**
 	 * DEPRECATED, please use {{#crossLink "AbstractSoundInstance/position:property"}}{{/crossLink}} directly as a property
 	 *

src/soundjs/webaudio/WebAudioSoundInstance.js

@@ -80,13 +80,24 @@ this.createjs = this.createjs || {};
 
 		/**
 		 * NOTE this is only intended for use by advanced users.
-		 * <br />A filterNode allowing frequency filtering. Connected to WebAudioSoundInstance {{#crossLink "WebAudioSoundInstance/panNode:property"}}{{/crossLink}}.
+		 * <br />A  ConvolverNode allowing application of convolver buffers (e.g. reverb) Connected to WebAudioSoundInstance {{#crossLink "WebAudioSoundInstance/panNode:property"}}{{/crossLink}}.
+		 * @property  convolverNode
+		 * @type { ConvolverNode}
+		 * @since 0.6.?
+		 */
+		this.convolverNode = s.context.createConvolver();
+		this.convolverNode.buffer = this.testBuffer;
+		this.convolverNode.connect(this.panNode); //convolver node => pan node => gain node
+
+		/**
+		 * NOTE this is only intended for use by advanced users.
+		 * <br />A filterNode allowing frequency filtering. Connected to WebAudioSoundInstance {{#crossLink "WebAudioSoundInstance/convolverNode:property"}}{{/crossLink}}.
 		 * @property filterNode
 		 * @type {BiquadFilterNode}
 		 * @since 0.6.?
 		 */
 		this.filterNode = s.context.createBiquadFilter();
-		this.filterNode.connect(this.panNode); //filter node => pan node => gain node
+		this.filterNode.connect(this.convolverNode); //filter node => convolver node => pan node => gain node
 
 		/**
 		 * NOTE this is only intended for use by advanced users.
@@ -96,7 +107,7 @@ this.createjs = this.createjs || {};
 		 * @since 0.6.?
 		 */
 		this.distortionNode = s.context.createWaveShaper();
-		this.distortionNode.connect(this.filterNode); //distortion node => filter node => pan node => gain node
+		this.distortionNode.connect(this.filterNode); //distortion node => filter node => convolver node => pan node => gain node
 
 		/**
 		 * NOTE this is only intended for use by advanced users.
@@ -244,6 +255,27 @@ this.createjs = this.createjs || {};
 		this.distortionNode.curve = this._makeDistortionCurve(this._distortionAmount);
 	};
 
+	p._updateConvolver = function() {
+		this.convolverNode.buffer = this._convolverBuffer;
+	};
+
+	p._getConvolverBufferFromFilepath = function(filepath) {
+		// grab audio track via XHR for convolver node
+		var req = new XMLHttpRequest();
+		req.open('GET', filepath, true);
+		req.responseType = 'arraybuffer';
+
+		var self = this; //save this reference
+		req.onload = function() {
+		  var audioData = req.response;
+		  s.context.decodeAudioData(audioData, function(buffer) {
+		  	self._convolverBuffer = buffer;
+		  	self._updateConvolver();
+		    }, function(e){"Error with decoding audio data" + e.err});
+		}
+		req.send();
+	};
+
 	p._removeLooping = function(value) {
 		this._sourceNodeNext = this._cleanUpAudioNode(this._sourceNodeNext);
 	};
@@ -317,10 +349,13 @@ this.createjs = this.createjs || {};
 	 * @since 0.4.1
 	 */
 	p._createAndPlayAudioNode = function(startTime, offset) {
+		console.log('createandplayaudionode');
 		var audioNode = s.context.createBufferSource();
 		audioNode.buffer = this.playbackResource;
-		//audioNode.connect(this.panNode);
 		audioNode.connect(this.distortionNode);
+		//audioNode.connect(this.convolverNode);
+		console.log('connected to convolverNode');
+
 		var dur = this._duration * 0.001;
 		audioNode.startTime = startTime + dur;
 		audioNode.start(audioNode.startTime, offset+(this._startTime*0.001), dur - offset);