How do I tell a AudioBufferSourceNode to start and end in the middle of a buffer?

Question

I'm using the HTML5 audio app to incorporate sounds into my game. How do I create a AudioBufferSourceNode that starts and stops playing in the middle of an AudioBuffer? I found nothing in the AudioBufferSourceNode interface for creating an AudioBufferSourceNode that begins in the middle of a buffer: https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#AudioBufferSourceNode I suppose I could create the AudioBufferSourceNode with a slice of the original AudioBuffer, but I want to conserve memory since my game already uses up a lot of javascript heap memory, so I really don't want to duplicate AudioBuffers or create portions thereof. I just want to make several AudioBufferSourceNodes that each play portions of a single AudioBuffer. How I do that?

Accepted Answer

Just use the additional (optional) parameters to `AudioBufferSourceNode#start`

```
// begin playback immediately, starting at second 10 of the buffer 
// and lasting 20 seconds
sourceNode.start( audioContext.currentTime, 10, 20 );
```

First parameter is `when`, which you're probably familiar with. This just determines when the sound will start playing, using the coordinate system of `AudioContext#currentTime`.

Second parameter is `offset`. This is the number of seconds into your `AudioBuffer` instance. So if you want to start playback at 10 seconds into the buffer, you'd pass `10` here.

Third parameter is `duration`. Also in seconds, and hopefully pretty self explanatory. In case it's not, this determines how long the sound will play for.

How do I tell a AudioBufferSourceNode to start and end in the middle of a buffer?

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