multi-touch in X

Mark markitect at
Thu Jul 12 22:44:36 CEST 2007

All the touch screens I have ever worked with give an x and y value of
distance from a corner.  These have been 4-pin resistive touch
screens.  If thats the case then the controller would have to be able
to switch which pins are drive and which read the data in order to get
two points.  (and the screens electrical path would have to be free of

Which if we can do: a 2-touch touchscreen would be a piece of cake.
Then we would just have to process the distance between touches and
determine if its a big finger or two separate locations.  Also this
would allow the touches to be picked up by the middle of the finger
which im guessing is how the iphone gets good finger keyboard

On 7/12/07, Tim Newsom <cephdon at> wrote:
> On Thu, 12 Jul 2007 13:07, Joe Pfeiffer wrote:
> > It strikes me as highly unlikely -- that would require hardware
> > changes.
> Getting the packages into gta02 does not require any hardware change.
> Making use of that functionality most likely will. I am sure that's what
> you meant, but I wanted to state it explicitly.  Adding software is
> easy... Adding new functionality like this is much harder when its not
> supported by hardware.
> --Tim

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