Bradley T. Hughes at
Mon Mar 1 07:09:12 PST 2010

On 03/01/2010 03:14 PM, ext Daniel Stone wrote:
> And from the NSTouch (OS X) class documentation:
>      Touches do not have a corresponding screen location. The first touch
>      of a touch collection is latched to the view underlying the cursor
>      using the same hit detection as mouse events.  Additional touches on
>      the same device are also latched to the same view as any other
>      touching touches.  A touch remains latched to its view until the
>      touch has either ended or is cancelled.

Very quickly, since I forgot to mention it in my original reply:

Bear in mind that this documentation is for OS X, and current Apple hardware 
only has multi-touch support via track-pads. There is no touch-screen 
hardware running Mac OS X today. It's either iPhone, iPod touch, or the 
upcoming iPad. iPhone and iPod touch use a different API than the above, 
UITouch instead of NSTouch, which actually does give on-screen locations (iirc).

The multi-focii discussions really only apply to multi-touch capable touch 
screens, not to laptop track-pads or external multi-touch capable tablets 
like some (all?) of the Wacom Bamboo tablets.

Bradley T. Hughes (Nokia-D-Qt/Oslo), at
Sandakervn. 116, P.O. Box 4332 Nydalen, 0402 Oslo, Norway

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