Touchscreen that works with Linux?

Can anyone recommend touchscreen manufacturers whose hardware works with PTB’s GetTouchDeviceIndices and Touch*** functions? ELO offer well made but expensive screens and they have Linux drivers, but at least one previous report doesn’t make it look hopeful, unless the problem was just being an older model: multiple touch screens

Single-touch would be sufficient, any advice greatly appreciated!

I can tell you that the builtin touchscreen of my Microsoft Surface Pro 6 works splendidly under Ubuntu 20.04-LTS. My girlfriend will soon test a touchscreen with Ubuntu 20.04-LTS for lab use, so that will provide another data-point within the next week or two i guess, a positive one i hope.

I know of at least one RaspberryPi 7" Touchsceen i own that doesn’t work well, because it violates the touch protocol specification, firmware bug i guess.

Unfortunately i was not ever able to test two touchscreens at once, due to lack of a 2nd touch screen apart from that broken RPi 7 screen, so i don’t know what the multiple touchscreen support is like, ie. if any bugs remain. I think all the reported problems on the forum were always only wrt. a setup with more than one touchscreen. Single-Touchscreen worked. And setup with multiple screens but only one of them a touchscreen also worked with some small configuration change.

In general, half-way modern USB connected touchscreens that use the Windows 8 multitouch protocol, and maybe have some kind of sticker a la “optimized for Windows 8” or whatever, should work well. Iow. all modern USB touch screens. Ofc. it is a should, because some of them have firmware bugs, so they don’t support the protocol properly and that’s where the fun begins. Cfe. this list in the kernel for “Windows 8 multitouch compliant” monitors that are mildly broken in one way or another and need special workarounds.

It is now possible to contract myself for looking into such things, although i’m pretty much booked out for the rest of this year and early next year, except maybe for smaller work without hard deadlines. https://www.psychtoolbox.net/
In such cases one would have to pay for work time and parts and materials, e.g., a touch screen or touch screens.

Thanks Mario! We have a few brands of touchscreen being used by several groups in our department, I’ll try some of these out then feedback any more info back to the thread.

So Celia tested the touchscreen in her lab a little bit. First test, plugging into Ubuntu 20.04-LTS machine and running our touch demos worked fine. More detailed tests forthcoming when she goes to the lab next time. This is the model:

They bought it from Amazon:

And then @katsangati reported another working model under Linux: “Dell 24 Touch Monitor - P2418HT. So far it’s working well with Linux (Ubuntu 20.04).”

Fwiw, I may also mention that our KeyboardLatencyTest script, among various other input devices, can also test touch-input timing if one uses the modality parameter 10. This is via detecting hard taps – and the associated bump noise – via microphone + PsychPortAudio audio onset timestamping. Obviously you’ll get the combined touch timing and audio timing error as an upper bound for timing precision / touch latency.

I’ve now tested a fairly economical Chinese industrial 21.5" touchscreen (~$170 in China, available on Alibaba internationally: here), that uses an ILITEK capacitive touch panel. It works using a dual X-screen configuration with up to 10 touch positions fine, no drivers needed.

I’ve also made a wiki page with some instructions on how to set up and calibrate touchscreens using two X-screens:

If anyone has any tips or advice please add them to that page. We can add more working touchscreens there too…

Were the iiyama touchscreens tested as a single screen or multi-screen?

Were the iiyama touchscreens tested as a single screen or multi-screen?

It’s only one touchscreen, but that one was tested by Celia together with two standard monitors in a triple-display setup. First one X-Screen with all three screens, then a dual-X-Screen setup with one experimenter monitor on X-Screen 0, and two stimulation displays on X-Screen 1, one of it being the touchscreen.

One more comment. help TouchInput is a good read, especially wrt. to setting up Linux to provide more detailed info about touch-points beyond mere touch location. The default libinput driver will be rather low on details, but the alternative evdev driver as explained there can provide additional info like touch surface area, pressure, proximity, touch angle etc. - Depending on the specific touch screen that is. Many models will only provide a subset of that info. MultiTouchDemo shows those extra properties when called with the optional verbosity flag 1.

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