QEvent::TouchUpdate event is not coming with any touch/multi-touch events

[sachintikare]

Hello,

I am following the steps specified in the mtdev installation guide for enabling multi-touch support for Embedded Qt in the below link,

http://www.ptrackapp.com/apclassys-notes/embedded-linux-multitouch/

When I run the pinchzoom example provided in the qTUIO/examples on my device, I am getting only QEvent::TouchBegin and QEvent::TouchEnd, but not getting QEvent::TouchUpdate. The multi-touch events are received as multiple touch events with only QEvent::TouchBegin/TouchEnd.

After some debugging I found that, qTUIO is not getting the calls to QTuio::updateTuioCursor() function, which is responsible for sending the QEvent::TouchUpdate event to Qt framework.

How do I fix this issue ?

Device details:
ARM compiler
Qt 4.8.5 for embedded linux
mtdev, tslib libraries

Thanks and Regards,
Sachin

[x29a]

Hi,

can you verify that your TUIO source is actually sending TouchUpdates? TuioClient::ProcessMessage() would be convenient to look at the TUIO packets.

Looking at the network traffic with wireshark might also shed some light into the nature of the packets.

[sachintikare]

Hi,

Thanks for replying.

I have verified this as well, the state of the frame cursor is always either "TUIO_REMOVED" or "TUIO_ADDED". The control is never going to the default case present in the switch case.

Thanks and Regards,
Sachin