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Posts: 43 | Thanked: 32 times | Joined on Jan 2010
#31
I have been thinking this for a while and I think it would be easier to emulate a touch on the screen via software (so it could be set to run with a key press or shortcutd)? I did a little research and found this http://forum.chumby.com/viewtopic.php?id=4585 . I tried to do something similar doing as root:
Code:
cat /dev/input/ts > ~/ts
left it running, touched the top left corner, back to xterminal and ctrl+c to stop it and seems to work as expected, but when I try
Code:
cat ~/ts > /dev/input/ts
I get "Permission denied".

I'm guessing new drivers might be needed.
Does anybody know how to get this to work?
 
Posts: 329 | Thanked: 505 times | Joined on Jul 2008 @ Israel
#32
Has anyone tried replacing the touch screen to a multitouch one?
http://www.mobile-phone-lcd.com/noki...dca-p-402.html

My digitizer died so I wondered if it is a possible upgrade... Obviously the software does not support multitouch but what if it did.

According to wikipedia there are resistive multitouch digitizers out there http://en.m.wikipedia.org/wiki/Resis...edirected=true
 
Posts: 323 | Thanked: 116 times | Joined on Jul 2010
#33
Why should I?

I prefere a resistive touch screen to a capacitive.

Better is an software emulation for (multitouch) pinch gesture.
I suggest "tap&swipe"

There are more important hardware mods to do:
(Upgrade of RAM memory e.g.)

A multitouch screen is useless for such little devices.
(The ipod nano touc 6g e.g. has a multitouch screen only to turn the content of the display: Stupid!!!)
 
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Posts: 234 | Thanked: 175 times | Joined on Jun 2010 @ Genova (Italy)
#34
I think you can't have multi touch emulation if you don't have multi-touch support in X server. You can send two input signal to the server at the same time, but it will always see one signal at a time without mulitouch support.
 
Posts: 256 | Thanked: 92 times | Joined on Oct 2010
#35
if you have multiple signals supporting multi touch you need no emulation(and in this case a x driver can help).

if you emulate, you interpret a single signal, and simulate some usecases by giving some sequences of signals special meaning(->gestures). but this is not that easy for a gesture may collide with other usecases.

Originally Posted by MaddogG View Post
I think you can't have multi touch emulation if you don't have multi-touch support in X server. You can send two input signal to the server at the same time, but it will always see one signal at a time without mulitouch support.
 
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Moderator | Posts: 2,622 | Thanked: 5,447 times | Joined on Jan 2010
#36
In the current implementation of resistive screens there are two films one with horizontal and one with vertical "cables". When they touch each other, there is current at the end of those cables, just off the screen. Correct me if I am wrong.
Theoretically, such a screen cannot support multitouch because when you touch two points, there are 2 horizontal and 2 vertical points that get current (except if the touches are aligned on one axis)
The question is: who interpolates the touch points and produces the midpoint, the controller or the software? Can we tap into the controller fw? If we get those 4 coordinates, then we can narrow down the possible touch points to 4. Perfectly enough for all common multitouch gestures.

Code:
     x1                       x2
--------------------------------------------
|    o                        x            |  y1
|                                          | 
|    x                        o            |  y2
--------------------------------------------
o --> real touch points
x --> possible touch points
________
LIVE SEX WEBSHOWS

Last edited by qwazix; 2011-08-21 at 10:44.
 
Posts: 256 | Thanked: 92 times | Joined on Oct 2010
#37
there were attempts to do that. all such attempts - afaik - failed..

Originally Posted by qwazix View Post
In the current implementation of resistive screens there are two films one with horizontal and one with vertical "cables". When they touch each other, there is current at the end of those cables, just off the screen. Correct me if I am wrong.
Theoretically, such a screen cannot support multitouch because when you touch two points, there are 2 horizontal and 2 vertical points that get current (except if the touches are aligned on one axis)
The question is: who interpolates the touch points and produces the midpoint, the controller or the software? Can we tap into the controller fw? If we get those 4 coordinates, then we can narrow down the possible touch points to 4. Perfectly enough for all common multitouch gestures.

Code:
     x1                       x2
--------------------------------------------
|    o                        x            |  y1
|                                          | 
|    x                        o            |  y2
--------------------------------------------
o --> real touch points
x --> possible touch points
 
Posts: 323 | Thanked: 116 times | Joined on Jul 2010
#38
Originally Posted by lunat View Post
if you have multiple signals supporting multi touch you need no emulation(and in this case a x driver can help).

if you emulate, you interpret a single signal, and simulate some usecases by giving some sequences of signals special meaning(->gestures). but this is not that easy for a gesture may collide with other usecases.
I think that a multi-touch x-driver could be useful also for emulating.
A multitouch driver also treats single touch events.

We could write a program that reads the events from the x-driver and writes back to the x-driver multi-touch events, when a specific combination of single touch events happens.

If we want to do this, the x-driver has to understand multi-touch events.
 
Posts: 256 | Thanked: 92 times | Joined on Oct 2010
#39
if you want to go there you might want to repeat to a second device.
and in this case i agree that it might be a good idea to have a look at how x drivers support multi touch.


Originally Posted by gerdich View Post
I think that a multi-touch x-driver could be useful also for emulating.
A multitouch driver also treats single touch events.

We could write a program that reads the events from the x-driver and writes back to the x-driver multi-touch events, when a specific combination of single touch events happens.

If we want to do this, the x-driver has to understand multi-touch events.
 

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Posts: 323 | Thanked: 116 times | Joined on Jul 2010
#40
Originally Posted by lunat View Post
if you want to go there you might want to repeat to a second device.
Like a second (multitouch) touchpad but fully emulated.

(P.S.: A driver for multitouch touchpads is useful in any case. I think of an external USB-Touchpad.)

Last edited by gerdich; 2010-12-01 at 17:56.
 
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