[Interest] [SOLVED] Re: Slow pointer follow in Qt 5.2.2 (git) on freescale i.MX6 with tslib

[Stefano Cordibella]

Eureka!
I solved the issue setting the maximum CPU frequency for my board with 
the command:

   echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Forgive me for this spam topic, reading the board documentation it was 
written that the maximum cpu frequency was the default value, but it 
isn't...

Cheers,
Stefano.

> Thank you for reporting your experience Jacob! My problem is that I am 
> forced to use an ltib environment for cross compiling, so it isn't so 
> simple to compile the required libraries to support X11 backend... Btw 
> I see that using eglfs in an application that don't use QML (the Qt 
> fingerpaint example), the pointer follow the finger at higher speed, 
> as it should happen... IMHO I think that the problem is bound to the 
> new qml engine or in the interaction with the tslib plugin... But I 
> don't know the library internals, so I cannot find any solution right 
> now. Stefano. On 03/06/2014 10:45 AM, Jacob Kroon wrote:
>> On Thu, Mar 6, 2014 at 10:20 AM, Stefano Cordibella
>> <stefano.cordibella at edalab.it  <mailto:stefano.cordibella at edalab.it>>
>> wrote:
>>
>>      Thank you Jacob for your suggestion,
>>          for this application the choice of using eglfs is not under my
>>      direct control, in addition to this I suppose that the use of X11
>>      can degrade the performance of the application (the target is a
>>      imx6 Single...).
>>
>>      Did you noticed a decrease in performance moving from eglfs to X11?
>>      Which imx6 did you used? Single Dual or Quad?
>>
>>
>> It's just been some very rude basic testing, running a custom QML
>> application on Wandboard Solo and Wandboard Quad.
>> I can't say I've seen any particular overhead in performance in
>> comparing X11/eglfs, but eglfs should in theory use less resources as
>> I see it.
>> As a humble Qt5 user I'm simply suspecting that the eglfs backend has
>> seen less use, and is not as mature as the X11 backend yet.
>>
>>
>>      Stefano.
>>
>>
>>      On 03/06/2014 10:05 AM, Jacob Kroon wrote:
>>>      Hi Stefano,
>>>
>>>      On Thu, Mar 6, 2014 at 9:22 AM, Stefano Cordibella
>>>      <stefano.cordibella at edalab.it
>>>      <mailto:stefano.cordibella at edalab.it>> wrote:
>>>
>>>          Hi Jacob,
>>>              right, I did not specify that I use eglfs.
>>>
>>>
>>>      I can just talk from my own personal experience in using
>>>      Qt5+iMX6. In 5.1.1, eglfs had a hard time tracking the mouse
>>>      pointer, 5.2.0 improved things a lot. But best experience sofar
>>>      has been in using the X11 backend instead of eglfs.
>>>
>>>          Stefano.
>>>
>>>
>>>          On 03/06/2014 08:53 AM, Jacob Kroon wrote:
>>>>          Hi Stefano,
>>>>
>>>>          On Thu, Mar 6, 2014 at 8:47 AM, Stefano Cordibella
>>>>          <stefano.cordibella at edalab.it
>>>>          <mailto:stefano.cordibella at edalab.it>> wrote:
>>>>
>>>>              Hi list,
>>>>                  using qt 5.2.2 (release branch from git, but I
>>>>              noticed the same issue with 5.2.1) on I.MX6 it is
>>>>              impossible to flick on qml elements, because the pointer
>>>>              does not "follow" the finger on touchscreen...
>>>>
>>>>              The strange issue is that with non-qml application
>>>>              (fingerpaint example) or using tslib test application
>>>>              (ts_test) on device the cursor follow the finger at
>>>>              higher speed.
>>>>              Is this a libqtslibplugin.so or a qml issue?
>>>>              I generated the plugin without any option, only qmake,
>>>>              make and make install...
>>>>
>>>>              I am using tslib library because my touchscreen does not
>>>>              support evdev (it is resistive?); I mean, trying to use
>>>>              EvdevTouch does not work at all, using EvdevMouse I see
>>>>              the pointer moving on screen, but the click doesn't work...
>>>>
>>>>              Any suggestion will be appreciated...
>>>>
>>>>          Which qpa backend are you using, xcb, wayland or eglfs ?
>>>          --
>>>          *Stefano Cordibella*
>>>          EDALab s.r.l. - Networked Embedded Systems
>>>
>>>          Strada Le Grazie, 15 - 37134 Verona - Italy
>>>          email :stefano.cordibella at edalab.it
>>>          <mailto:stefano.cordibella at edalab.it>
>>>          skype : stefano.cordibella
>>>          tel. : +39 045 802 70 85 <tel:%2B39%20045%20802%2070%2085>
>>>          web :www.edalab.it  <http://www.edalab.it>
>>>
>>>
>>>
>>>
>>>      --
>>>        -- Jacob
>>      --
>>      *Stefano Cordibella*
>>      EDALab s.r.l. - Networked Embedded Systems
>>
>>      Strada Le Grazie, 15 - 37134 Verona - Italy
>>      email :stefano.cordibella at edalab.it
>>      <mailto:stefano.cordibella at edalab.it>
>>      skype : stefano.cordibella
>>      tel. : +39 045 802 70 85 <tel:%2B39%20045%20802%2070%2085>
>>      web :www.edalab.it  <http://www.edalab.it>
>>
>>
>>
>>
>> -- 
>>    -- Jacob
> -- *Stefano Cordibella* EDALab s.r.l. - Networked Embedded Systems 
> Strada Le Grazie, 15 - 37134 Verona - Italy email : 
> stefano.cordibella at edalab.it skype : stefano.cordibella tel. : +39 045 
> 802 70 85 web : www.edalab.it

-- 
*Stefano Cordibella*
EDALab s.r.l. - Networked Embedded Systems

Strada Le Grazie, 15 - 37134 Verona - Italy
email : stefano.cordibella at edalab.it
skype : stefano.cordibella
tel. : +39 045 802 70 85
web : www.edalab.it
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