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refactor decodeSound function, to only use sound data buffer to decode the sound instead of relying metadata from the project json

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Karishma Chadha 2018-04-13 11:40:34 -04:00
parent 84fdf5c76a
commit 158adb0868
1 changed files with 31 additions and 25 deletions
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56
src/index.js
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@ -189,7 +189,6 @@ class AudioEngine {
* Store a reference to it the sound in the audioBuffers dictionary, indexed by soundId * Store a reference to it the sound in the audioBuffers dictionary, indexed by soundId
* @param {object} sound - an object containing audio data and metadata for a sound * @param {object} sound - an object containing audio data and metadata for a sound
* @property {Buffer} data - sound data loaded from scratch-storage. * @property {Buffer} data - sound data loaded from scratch-storage.
* @property {string} format - format type, either empty or adpcm.
* @returns {?Promise} - a promise which will resolve to the soundId if decoded and stored. * @returns {?Promise} - a promise which will resolve to the soundId if decoded and stored.
*/ */
decodeSound (sound) { decodeSound (sound) {
@ -197,38 +196,45 @@ class AudioEngine {
let loaderPromise = null; let loaderPromise = null;
// Make a copy of the buffer because decoding detaches the original buffer // Make a copy of the buffer because decoding detaches the original buffer
const bufferCopy = sound.data.buffer.slice(0); const bufferCopy1 = sound.data.buffer.slice(0);
switch (sound.format) { // Attempt to decode the sound using the browser's native audio data decoder
case '': // Check for newer promise-based API
// Check for newer promise-based API if (this.audioContext.decodeAudioData.length === 1) {
if (this.audioContext.decodeAudioData.length === 1) { loaderPromise = this.audioContext.decodeAudioData(bufferCopy1);
loaderPromise = this.audioContext.decodeAudioData(bufferCopy); } else {
} else { // Fall back to callback API
// Fall back to callback API loaderPromise = new Promise((resolve, reject) => {
loaderPromise = new Promise((resolve, reject) => { this.audioContext.decodeAudioData(bufferCopy1,
this.audioContext.decodeAudioData(bufferCopy, decodedAudio => resolve(decodedAudio),
decodedAudio => resolve(decodedAudio), error => reject(error)
error => reject(error) );
); });
});
}
break;
case 'adpcm':
loaderPromise = (new ADPCMSoundDecoder(this.audioContext)).decode(bufferCopy);
break;
default:
return log.warn('unknown sound format', sound.format);
} }
const storedContext = this; const storedContext = this;
return loaderPromise.then( return loaderPromise.then(
decodedAudio => { decodedAudio => {
storedContext.audioBuffers[soundId] = decodedAudio; storedContext.updateSoundBuffer(soundId, decodedAudio);
return soundId; return soundId;
}, },
error => { () => {
log.warn('audio data could not be decoded', error); // The audio context failed to parse the sound data
// we gave it, so try to decode as 'adpcm'
// First we need to create another copy of our original data
const bufferCopy2 = sound.data.buffer.slice(0);
// Try decoding as adpcm
return (new ADPCMSoundDecoder(this.audioContext)).decode(bufferCopy2)
.then(
decodedAudio => {
storedContext.updateSoundBuffer(soundId, decodedAudio);
return soundId;
},
sndError => {
log.warn('audio data could not be decoded', sndError);
}
);
} }
); );
} }