Re: compassCalibrated vs accuracy?

Hi Dean,

Thanks for the email!

On Mon, Feb 14, 2011 at 7:04 PM, Dean Jackson <dino@apple.com> wrote:
> Hi,
>
> One of the engineers who worked on Apple's Core Motion API passed on some feedback related to compassCalibrated. He suggests that a float property called "accuracy" would be better suited - taking a value between 0 and 1.
>
> The reasoning is that a developer shouldn't really be concerned with calibration. All they really need to know is the accuracy of the data they are seeing. Also, future hardware may not need calibration, but will still have variance in accuracy.
>
> A value of 0 for accuracy could still trigger a dialog by the system asking for compass calibration (on iOS this prompts the user to do a figure-8 movement with the device). A value of 1 would mean that your data is as accurate as possible. Anything in between could be used in the UI to suggest you're not getting perfect data.
>

This sounds reasonable, although I am wondering what exactly would the
application do with the numerical value. The above usecase seems to
split the values into 3 buckets:

0 - calibration needed,
(0, 1)  - data isn't perfect,
1 - data is as accurate as possible

which makes me wonder if it wouldn't be simpler if we rather had
'accuracy' as an enumeration (e.g. ACCURACY_LOW/MEDIUM/HIGH) ? Or are
there a usecases where the actual numeric value could be used for
something other than prompting the user to calibrate?

> I don't want to hold up FPWD for this comment. Please consider it simply feedback on the draft.
>

Thanks for considering this :) My guess is that such a change wouldn't
hold up FPWD.

All the best,
Andrei

Received on Monday, 14 February 2011 19:28:05 UTC