Re: Philips Dexscape TouchScreen Problem

["darren_karp2001" <darren.karp@xxxxxxxxx>]

Hi Keith,

Even setting the main display to 1024 x 768 to match the TS screen
and cloning doesn't make much difference, its pretty accurate on the
far left side but gets worse the further to the right you move.

Extending the desktop and making the TS the primary has no effect,
in fact the TS doesn't work!

Darren



>
> Hi Darren,
>
> I did some work on touchscreens a year or so ago.
>
> They report their position as an absolute value that is the same
> irrespective of resolution. Windows then takes this value and
scales it
> based on the actual display resolution that the machine is running
and
> converts it to a pixel coordinate.
>
> Try running BOTH screens at the same resolution and it should then
be
> reasonable accurate.
>
> You say you are cloning the display, but in reality you are
scaling the
> display as you are running different resolutions on both screens
even though
> they look the same.
>
> Quite how you overcome the problem, I dont know, but I hope I
might have hit
> upon the cause.
>
> When I was messing about with reading the touch screen in VB I got
one of
> the calculations wrond and flipped the touch screen top left
corner to
> bottom right. Was quite fun to try and press on the wrong bit of
the screen
> to get the button you wanted :)
>
> Regards
>
> Keith
>
> > -----Original Message-----
> > From: ukha_d@xxxxxxx [mailto:ukha_d@xxxxxxx]On
Behalf Of
> > darren_karp2001
> > Sent: 02 May 2006 09:41
> > To: ukha_d@xxxxxxx
> > Subject: [ukha_d] Re: Philips Dexscape TouchScreen Problem
> >
> >
> > Something like that Phil, yes.
> >
> > As I said if I extend my desktop on to the touchscreen the
> > touchscreen does nothing (apart from displaying the desktop of
> > course), but if I clone it then the touchscreen works but its
out of
> > alignment. In the center of the screen it seems good but as you
move
> > out it gets worse.
> >
> > If I match the resolution to 1024 x 768 then at the lefthand
side of
> > the touchscreen its accurate but the further right I go the
worst it
> > gets!
> >
> > Very odd...and very annoying.
> >
> > Any tips?
> > Darren
> >
> >
> >
> > --- In ukha_d@xxxxxxx, "Phil Harris" <phil@>
wrote:
> > >
> > >
> > > > -----Original Message-----
> > > > From: ukha_d@xxxxxxx [mailto:ukha_d@xxxxxxx]
> > > > On Behalf Of darren_karp2001
> > > > Sent: 02 May 2006 08:52
> > > > To: ukha_d@xxxxxxx
> > > > Subject: [ukha_d] Re: Philips Dexscape TouchScreen
Problem
> > > >
> > > > Nice try Phil :)
> > >
> > > Why thankyou...
> > >
> > > > It's really rather weird. It appears from doing some
basic
> > > > research that when you extend a desktop on to a
touchscreen
> > > > monitor Windows no longer receives the input, but as a
clone
> > > > it works but as I said the alignment is WAY off (over
an
inch).
> > > >
> > > > I'm thinking that it has something to do with the fact
that
> > > > the resolution of the main desktop is 1280 x 1024 and
the
> > > > touchscreen is 1024 x 768 but that shouldn't really
matter
> > > > I would have thought.
> > >
> > > I'm assuming that the touchscreen driver probably reports
its
> > coordinates
> > > back on a scale of 1024 x 768 whereas you are feeding it a
desktop
> > image
> > > that is larger than that - does it at one corner get more
accurate
> > whilst at
> > > the diagonally opposite corner get further and further out?
> > >
> > > Phil
> > >
> >
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
>