Missing a way to set the start time of sound components

[JonathannJacobs]

Hi, well first thing, it's not a bug but a missing feature.

I wish to have a way to play a sound entirely at first loop and then rewind at some specific start loop value different than zero.
So far i had the following code :

this.el.removeAttribute('sound')
this.el.setAttribute('sound', 'src', 'assets/some.mp3');
this.el.components.sound.playSound()
this.el.addEventListener('sound-ended', () => {
// Missing here a way to set the next playSound start value
this.el.components.sound.playSound()
});

And that is sad because i could totally do it with a regular audio html element that lacks positionnal audio and pool.

Currently my best shot is to split my file into two mp3: one for the intro and another for the looping part.

• A-Frame Version: 1.4.2
• Platform / Device: All

[mrxz]

It would be nice for the built-in sound component to expose a loopStart and loopEnd, but currently it doesn't. Luckily you can quite easily reach into the sound component and get to the THREE.Audio instance or even further to the underlying WebAudio Nodes.

For example:

const soundComponent = this.el.components['sound'];
const audio = soundComponent.pool.children[0]; // THREE.Audio
audio.setLoopStart(/* start time in seconds */);
audio.setLoopEnd(audio.buffer.duration)

It can be a bit tricky when to execute this, as it needs to take place after the sound component has initialized (and the sound loaded, for the duration), but before playing the audio (otherwise the loopStart and loopEnd of THREE.Audio don't apply). Should be good to handle it in sound-loaded: this.el.addEventListener('sound-loaded', e => {})

[JonathannJacobs]

Indeed, that's usefull info. Thank you
I also found out that playSound does take a callback for preprocessing sounds which can be used for this purpose, but there is also an issue here : if the sound isn't loaded yet, mustPlay will be set to true and function will return immediatly, forgetting to save whatever callback we did set. And this is a bug actually.

[JonathannJacobs]

Wrote a fix and commited it. If it is accepted here should be the solution to my issue :
this.el.removeAttribute('sound')
this.el.setAttribute('sound', 'src', 'assets/some.mp3');
this.el.components.sound.playSound((snd) => {
snd.setLoop(true)
snd.setLoopStart(playbackTime) // set your loop restart time here, in seconds
snd.setLoopEnd(snd.buffer.duration) // Up to the end or else
})

[dmarcos]

Fixed by #5365