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Re: [sensors] Batching API for sensor readings

From: Tobie Langel via GitHub <sysbot+gh@w3.org>
Date: Fri, 24 Feb 2017 12:27:27 +0000
To: public-device-apis-log@w3.org
Message-ID: <issue_comment.created-282279751-1487939246-sysbot+gh@w3.org>
> To meet this use case we need an uninterrupted recording all the 
time, note that samples can be lost even during notification that the 
given buffer is full and while refreshing the buffer.

Would you write to the buffer directly as you get the samples from the
 HAL (or equivalent) or would you write to it with each animation 
frame?

If its the former, we indeed need a buffer swapping mechanism of some 
sort. If it's the latter the buffer can be swapped synchronously by 
the API consumer during rAF (or right before? I'm not sure about the 
particulars of this) if they're advised the buffer is about to be 
filled, no?

```js
let gyro = new Gyroscope();
let bufferA = Float64Array(gyro.getReadingSize() * n);
let bufferB = Float64Array(gyro.getReadingSize() * n);
gyro.onbufferfull = _ => {
  if (gyro.buffer === bufferA) {
    gyro.buffer = bufferB;
  } else {
    gyro.buffer = bufferA;
  }
};
```

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Received on Friday, 24 February 2017 12:27:35 UTC

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