Re: Comment on Device Orientation API

Hi Martin,

Thanks for your suggestion.  This is an interesting idea, and one that was discussed.  The draft states:

    The event should fire whenever a significant change in orientation occurs. The definition of a significant change in this context is left to the implementation. Implementations may also fire the event if they have reason to believe that the page does not have sufficiently fresh data.

I tend to think that Opera filtering at 4 degrees is a UA bug.  Maybe a RFE.  I do not think I want to expose tighter control here to web application.  Surely any change to the API allowing such control could be veto'ed by the UA.  Opera could still cap their notifications at 4 degree changes even though the web application asked for something tighter. 

It could also be an implementation concern.  I know when I fire lots of events, the over all browser performance suffers.  I think UA's need some flexibility here to provide the best possible performance.

Thanks again,

Doug Turner 



On Feb 29, 2012, at 6:46 AM, Martin Lechner wrote:

> Dear members of the Geolocation Working Group,
> 
> I am Martin Lechner, CTO of Wikitude, a member of W3C and developer of the Wikitude World Browser.
> 
> We are currently developing an augmented reality project on platforms based on the DeviceOrientation API, and do have a comment regarding some specific items in the draft specification.
> 
> The current specified update rate of the device orientation event is not sufficient for our usecase. Specifically the phrase: “the event should fire whenever a significant change in orientation occurs.” leaves it up to the implementation when exactly to fire an event.
> 
> We are already seeing different implementation in the prerelease versions of Opera (LAB Opera Mobile) and Mozilla (Aurora). While Mozilla reports events quite frequently (which is preferred by us), Opera matches the specification and reports events only if there is a change of approximately 4 degrees.
> 
> Our suggestion would be to let the web developer define how accurate the orientation changes should be reported. E.g. like the accuracy modes in Geolocation API. For AR it would be nice to have a high accuracy to achieve more events to get a smoother, more accurate calculation when moving the device.
> 
> Best regards,
> Martin Lechner
> 
> -- 
> - - -
> Martin Lechner
> CTO
> 
> Wikitude GmbH
> Ginzkeyplatz 11
> 5020 Salzburg/Austria
> Phone +43 662 243310
> Mobile +43 676 840 856 300
> 
> http://www.wikitude.com
> 
> 
>

Received on Wednesday, 29 February 2012 20:41:12 UTC