Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. Mobile and Embedded
  4. Touchscreen cannot rotate with linuxfb evdevtouch
Forum Updated to NodeBB v4.3 + New Features

Touchscreen cannot rotate with linuxfb evdevtouch

Scheduled Pinned Locked Moved Unsolved Mobile and Embedded
1 Posts 1 Posters 304 Views
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • E Offline
    E Offline
    Edmond.Yu
    wrote on last edited by
    #1

    I'm using QT 5.11 on Raspbian GNU/Linux 10 (buster),
    The display is rotated but the touchscreen cannot rotate by the following startup parameters:

    pi@raspberrypi:~ $ export QT_QPA_EVDEV_TOUCHSCREEN_PARAMETERS="rotate=270"
    pi@raspberrypi:~ $ ./ucapp -platform linuxfb  -plugin evdevtouch
    

    Refer the document:
    https://doc.qt.io/qt-5/embedded-linux.html
    https://doc.qt.io/qt-5/inputs-linux-device.html

    After hook the QEvent as the following:

    bool MainWindow::eventFilter(QObject *obj, QEvent *event)
    {
        if(event->type()==QEvent::HoverMove)
        {
            auto e = (QHoverEvent*) event;
            auto p = e->pos();
            qDebug()<<"rx "<<p.rx() <<";ry "<<p.ry()<<"\n";
        }
    
        return QMainWindow::eventFilter(obj, event);
    }
    

    There are two line messages when I touch the left-top point on touchscreen.
    It seems one for original point and one for transformed point.

    09-29 07:52:25 Debug: rx  39 ;ry  767
    09-29 07:52:25 Debug: rx  19 ;ry  65
    

    when I set rotate=0, there is only one line message for one touch:

    export QT_QPA_EVDEV_TOUCHSCREEN_PARAMETERS="rotate=0",
    

    I haven't digged into the source code qevdevtouchhandler.cpp.
    https://github.com/qt/qtbase/blob/dev/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp

    Please give me ideals to fix the issue. I have struggled and searched for several days

    1 Reply Last reply
    0

    • Login

    • Login or register to search.
    • First post
      Last post
    0
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Groups
    • Search
    • Get Qt Extensions
    • Unsolved