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Use “audioContext” to refer to webAudioContext

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This commit is contained in:
Eric Rosenbaum 2017-06-22 10:51:57 -04:00
parent 90af375b03
commit 0bc892f03d
6 changed files with 43 additions and 31 deletions
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10
src/ADPCMSoundDecoder.js
View file

@ -9,8 +9,12 @@ const log = require('./log');
* https://github.com/LLK/scratch-flash/blob/master/src/sound/WAVFile.as
*/
class ADPCMSoundDecoder {
constructor (context) {
this.context = context;
/**
* @param {AudioContext} audioContext - a webAudio context
* @constructor
*/
constructor (audioContext) {
this.audioContext = audioContext;
}
/**
* Data used by the decompression algorithm
@ -79,7 +83,7 @@ class ADPCMSoundDecoder {
const samples = this.imaDecompress(this.extractChunk('data', stream), this.adpcmBlockSize);
const buffer = this.context.createBuffer(1, samples.length, this.samplesPerSecond);
const buffer = this.audioContext.createBuffer(1, samples.length, this.samplesPerSecond);
// @todo optimize this? e.g. replace the divide by storing 1/32768 and multiply?
for (let i = 0; i < samples.length; i++) {

10
src/DrumPlayer.js
View file

@ -3,11 +3,11 @@ const SoundPlayer = require('./SoundPlayer');
class DrumPlayer {
/**
* A prototype for the drum sound functionality that can load drum sounds, play, and stop them.
* @param {AudioContext} context - a webAudio context
* @param {AudioContext} audioContext - a webAudio context
* @constructor
*/
constructor (context) {
this.context = context;
constructor (audioContext) {
this.audioContext = audioContext;
const baseUrl = 'https://raw.githubusercontent.com/LLK/scratch-audio/develop/sound-files/drums/';
const fileNames = [
@ -34,7 +34,7 @@ class DrumPlayer {
this.drumSounds = [];
for (let i = 0; i < fileNames.length; i++) {
this.drumSounds[i] = new SoundPlayer(this.context);
this.drumSounds[i] = new SoundPlayer(this.audioContext);
// download and decode the drum sounds
// @todo: use scratch-storage to manage these sound files
@ -44,7 +44,7 @@ class DrumPlayer {
request.responseType = 'arraybuffer';
request.onload = () => {
const audioData = request.response;
this.context.decodeAudioData(audioData).then(buffer => {
this.audioContext.decodeAudioData(audioData).then(buffer => {
this.drumSounds[i].setBuffer(buffer);
});
};

10
src/InstrumentPlayer.js
View file

@ -9,11 +9,11 @@ class InstrumentPlayer {
* play note or set instrument block runs, causing a delay of a few seconds.
* Using this library we don't have a way to set the volume, sustain the note beyond the sample
* duration, or run it through the sprite-specific audio effects.
* @param {AudioContext} context - a webAudio context
* @param {AudioContext} audioContext - a webAudio context
* @constructor
*/
constructor (context) {
this.context = context;
constructor (audioContext) {
this.audioContext = audioContext;
this.outputNode = null;
// Instrument names used by Musyng Kite soundfont, in order to
@ -42,7 +42,7 @@ class InstrumentPlayer {
this.loadInstrument(instrumentNum)
.then(() => {
this.instruments[instrumentNum].play(
note, this.context.currentTime, {
note, this.audioContext.currentTime, {
duration: sec,
gain: gain
}
@ -59,7 +59,7 @@ class InstrumentPlayer {
if (this.instruments[instrumentNum]) {
return Promise.resolve();
}
return Soundfont.instrument(this.context, this.instrumentNames[instrumentNum])
return Soundfont.instrument(this.audioContext, this.instrumentNames[instrumentNum])
.then(inst => {
inst.connect(this.outputNode);
this.instruments[instrumentNum] = inst;

10
src/SoundPlayer.js
View file

@ -4,8 +4,12 @@ const log = require('./log');
* A SoundPlayer stores an audio buffer, and plays it
*/
class SoundPlayer {
constructor (context) {
this.context = context;
/**
* @param {AudioContext} audioContext - a webAudio context
* @constructor
*/
constructor (audioContext) {
this.audioContext = audioContext;
this.outputNode = null;
this.buffer = null;
this.bufferSource = null;
@ -60,7 +64,7 @@ class SoundPlayer {
return;
}
this.bufferSource = this.context.createBufferSource();
this.bufferSource = this.audioContext.createBufferSource();
this.bufferSource.buffer = this.buffer;
this.bufferSource.playbackRate.value = this.playbackRate;
this.bufferSource.connect(this.outputNode);

10
src/effects/PanEffect.js
View file

@ -5,9 +5,13 @@
* Clamped -100 to 100
*/
class PanEffect {
constructor (context) {
this.context = context;
this.panner = this.context.createStereoPanner();
/**
* @param {AudioContext} audioContext - a webAudio context
* @constructor
*/
constructor (audioContext) {
this.audioContext = audioContext;
this.panner = this.audioContext.createStereoPanner();
this.value = 0;
}

24
src/index.js
View file

@ -26,11 +26,11 @@ class AudioPlayer {
// Create the audio effects
this.pitchEffect = new PitchEffect();
this.panEffect = new PanEffect(this.audioEngine.context);
this.panEffect = new PanEffect(this.audioEngine.audioContext);
// Chain the audio effects together
// effectsNode -> panEffect -> audioEngine.input -> destination (speakers)
this.effectsNode = this.audioEngine.context.createGain();
this.effectsNode = this.audioEngine.audioContext.createGain();
this.effectsNode.connect(this.panEffect.panner);
this.panEffect.connect(this.audioEngine.input);
@ -58,7 +58,7 @@ class AudioPlayer {
}
// create a new soundplayer to play the sound
const player = new SoundPlayer(this.audioEngine.context);
const player = new SoundPlayer(this.audioEngine.audioContext);
player.setBuffer(this.audioEngine.audioBuffers[md5]);
player.connect(this.effectsNode);
this.pitchEffect.updatePlayer(player);
@ -150,21 +150,21 @@ class AudioPlayer {
class AudioEngine {
constructor () {
const AudioContext = window.AudioContext || window.webkitAudioContext;
this.context = new AudioContext();
this.audioContext = new AudioContext();
this.input = this.context.createGain();
this.input.connect(this.context.destination);
this.input = this.audioContext.createGain();
this.input.connect(this.audioContext.destination);
// global tempo in bpm (beats per minute)
this.currentTempo = 60;
// instrument player for play note blocks
this.instrumentPlayer = new InstrumentPlayer(this.context);
this.instrumentPlayer = new InstrumentPlayer(this.audioContext);
this.instrumentPlayer.outputNode = this.input;
this.numInstruments = this.instrumentPlayer.instrumentNames.length;
// drum player for play drum blocks
this.drumPlayer = new DrumPlayer(this.context);
this.drumPlayer = new DrumPlayer(this.audioContext);
this.numDrums = this.drumPlayer.drumSounds.length;
// a map of md5s to audio buffers, holding sounds for all sprites
@ -204,10 +204,10 @@ class AudioEngine {
switch (sound.format) {
case '':
loaderPromise = this.context.decodeAudioData(bufferCopy);
loaderPromise = this.audioContext.decodeAudioData(bufferCopy);
break;
case 'adpcm':
loaderPromise = (new ADPCMSoundDecoder(this.context)).decode(bufferCopy);
loaderPromise = (new ADPCMSoundDecoder(this.audioContext)).decode(bufferCopy);
break;
default:
return log.warn('unknown sound format', sound.format);
@ -297,8 +297,8 @@ class AudioEngine {
if (!this.mic && !this.connectingToMic) {
this.connectingToMic = true; // prevent multiple connection attempts
navigator.mediaDevices.getUserMedia({audio: true}).then(stream => {
this.mic = this.context.createMediaStreamSource(stream);
this.analyser = this.context.createAnalyser();
this.mic = this.audioContext.createMediaStreamSource(stream);
this.analyser = this.audioContext.createAnalyser();
this.mic.connect(this.analyser);
this.micDataArray = new Float32Array(this.analyser.fftSize);
})