W3C home > Mailing lists > Public > whatwg@whatwg.org > September 2009

[whatwg] Orientation event in Firefox

From: Simon Fraser <smfr@mac.com>
Date: Fri, 18 Sep 2009 13:45:26 -0700
Message-ID: <F4FB2058-7DCB-4359-A342-99EF8AFFF5D6@mac.com>
I'm a little concerned about use of the word "orientation" for these  
kinds of events.

WebKit on iPhone already uses the term "orientation" to mean "which  
way up is the device", i.e. in portrait or landscape, right-way-up or  
upside-down:
<http://developer.apple.com/iphone/library/documentation/AppleApplications/Reference/SafariWebContent/HandlingEvents/HandlingEvents.html#//apple_ref/doc/uid/TP40006511-SW16 
 >

What you're talking about here is getting data from the accelerometer  
to describe arbitrary positions, so I think it would be clearer if  
these were called "accelerometer" events, or something else that  
distinguishes them from the usage that only applies to the cardinal  
angles.

Simon

On Sep 2, 2009, at 2:26 PM, Dave Burke wrote:

> On Mon, Aug 31, 2009 at 11:06 PM, Doug Turner  
> <doug.turner at gmail.com> wrote:
> Thanks Dave for your comments.
>
> I was thinking about update frequency.  right now, it is up to the  
> UA (we are using 50ms).
>
> To give an explicit example, if you want to run a high pass (say to  
> detect only sudden movements), you might code a simple k-order FIR  
> filter of the form:
>
>    y[n] = b0.x[n] + b1.x[n-1] + ... +  bk.x[n-k]
>
> The coefficient values b0 ... bk are a function of the sampling rate  
> ("update frequency") and hence needs to be settable or at least  
> known to allow code portability.
>
>
> units -- yes.  in g.  This is best.
>
> magnetometer -- but in a different API, right?  I do not see  
> directly how you would combined the two.
>
> It's a different API, but (can be) closely related. You can present  
> magnetometer information either as x, y, z of the magnetic field  
> vector or as the special case of compass orientation. For example,  
> Android has the same SensorEvent for both Sensor.TYPE_ACCELEROMETER  
> and Sensor.TYPE_MAGNETIC_FIELD. Lots of interesting use-cases for  
> compass ranging from map tile orientation, navigation, augmented  
> reality, etc.
>
>
> Also see: http://dougt.org/wordpress/2009/08/orientation-update/ for  
> some demos.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20090918/9f2821cc/attachment.htm>
Received on Friday, 18 September 2009 13:45:26 UTC

This archive was generated by hypermail 2.3.1 : Monday, 13 April 2015 23:08:52 UTC