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Forum Update on Monday, May 27th 2025

QWS VNC doesn't work on Portrait mode

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #8

    If I understand the patch correctly, it only check other screens if the main screen is not transformed. Since you have more that one screen transformed, you should check all screens (main + sub-screens)

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

    K 1 Reply Last reply
    0
    • SGaistS SGaist

      If I understand the patch correctly, it only check other screens if the main screen is not transformed. Since you have more that one screen transformed, you should check all screens (main + sub-screens)

      K Offline
      K Offline
      kumararajas
      wrote on last edited by
      #9

      @SGaist Then it means that, the else part of code, should be done for if condition as well?

          if (qt_screen->isTransformed()) 
          {
              QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
              tpos = qt_screen->mapFromDevice(pos, s);
          } 
          //tpos = pos;
          // Only in case of Multi Display
          // If main screen is not transformed, then check if sub screens are transformed
          QList<QScreen*> screens = qt_screen->subScreens();
          if (screens.size() && !bRemote) 
          {
              for (int i = 0; i < screens.size(); ++i) 
              {
                  QScreen *screen = screens.at(i);
                  if (screen->isTransformed())
                  {
                      QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                      tpos = screen->mapFromDevice(pos, s);
                      break;
                  }
              }
          }
      

      Is it like that?

      --Kumar

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #10

        I'd remove also the bRemote, just check them all

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        K 1 Reply Last reply
        0
        • SGaistS SGaist

          I'd remove also the bRemote, just check them all

          K Offline
          K Offline
          kumararajas
          wrote on last edited by
          #11

          @SGaist Hmm, let me test this.

          Just for better understanding attaching the modified code:

          if (qt_screen->isTransformed()) 
              {
                  QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                  tpos = qt_screen->mapFromDevice(pos, s);
              } 
              //tpos = pos;
              // Only in case of Multi Display
              // If main screen is not transformed, then check if sub screens are transformed
              QList<QScreen*> screens = qt_screen->subScreens();
              if (screens.size()) 
              {
                  for (int i = 0; i < screens.size(); ++i) 
                  {
                      QScreen *screen = screens.at(i);
                      if (screen->isTransformed())
                      {
                          QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                          tpos = screen->mapFromDevice(pos, s);
                          break;
                      }
                  }
              } 
          

          I'll test and keep you posted..

          --Kumar

          K 1 Reply Last reply
          0
          • K kumararajas

            @SGaist Hmm, let me test this.

            Just for better understanding attaching the modified code:

            if (qt_screen->isTransformed()) 
                {
                    QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                    tpos = qt_screen->mapFromDevice(pos, s);
                } 
                //tpos = pos;
                // Only in case of Multi Display
                // If main screen is not transformed, then check if sub screens are transformed
                QList<QScreen*> screens = qt_screen->subScreens();
                if (screens.size()) 
                {
                    for (int i = 0; i < screens.size(); ++i) 
                    {
                        QScreen *screen = screens.at(i);
                        if (screen->isTransformed())
                        {
                            QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                            tpos = screen->mapFromDevice(pos, s);
                            break;
                        }
                    }
                } 
            

            I'll test and keep you posted..

            K Offline
            K Offline
            kumararajas
            wrote on last edited by
            #12

            No success yet!

            While running the application with Multi for VNC, still the touch inputs on the device is still not rotated.

            --Kumar

            K 1 Reply Last reply
            0
            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #13

              Silly idea (and just to verify) but what about just dropping the if and do the transform for all screens anyway ?

              Interested in AI ? www.idiap.ch
              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

              K 2 Replies Last reply
              0
              • K kumararajas

                No success yet!

                While running the application with Multi for VNC, still the touch inputs on the device is still not rotated.

                K Offline
                K Offline
                kumararajas
                wrote on last edited by kumararajas
                #14

                Just for more information:

                export QWS_DISPLAY="Multi: VNC:0:size=480x640 Transformed:rot0"
                

                This displays the UI in a landscape mode and the touch input works as per the UI.

                export QWS_DISPLAY="Multi: VNC:0:size=480x640 Transformed:rot90"
                

                This rotates the UI to 90 degrees. But the touch input is as same as 0 degrees.

                This clearly indicates that the display transformation works good but the transformation to touch input mapping is not working.

                --Kumar

                1 Reply Last reply
                0
                • SGaistS SGaist

                  Silly idea (and just to verify) but what about just dropping the if and do the transform for all screens anyway ?

                  K Offline
                  K Offline
                  kumararajas
                  wrote on last edited by
                  #15

                  @SGaist Sam, can you please send me the code snippet to be on same page?

                  Thanks,
                  Kumara

                  --Kumar

                  1 Reply Last reply
                  0
                  • SGaistS SGaist

                    Silly idea (and just to verify) but what about just dropping the if and do the transform for all screens anyway ?

                    K Offline
                    K Offline
                    kumararajas
                    wrote on last edited by
                    #16

                    @SGaist You mean to try this kind of code:

                    QList<QScreen*> screens = qt_screen->subScreens();
                    if (screens.size()) 
                    {
                        for (int i = 0; i < screens.size(); ++i) 
                        {
                            QScreen *screen = screens.at(i);
                            QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                            tpos = screen->mapFromDevice(pos, s);
                            break;
                        }
                    }
                    

                    instead of

                    if (qt_screen->isTransformed()) 
                        {
                            QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                            tpos = qt_screen->mapFromDevice(pos, s);
                        } 
                        else 
                        {
                            //tpos = pos;
                            // Only in case of Multi Display
                            // If main screen is not transformed, then check if sub screens are transformed
                            QList<QScreen*> screens = qt_screen->subScreens();
                            if (screens.size() && !bRemote) 
                            {
                                for (int i = 0; i < screens.size(); ++i) 
                                {
                                    QScreen *screen = screens.at(i);
                                    if (screen->isTransformed())
                                    {
                                        QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                                        tpos = screen->mapFromDevice(pos, s);
                                        break;
                                    }
                                }
                            }
                        }
                    

                    Sam, if you confirm, I can make these changes and build my packages.

                    Thanks,
                    Kumara

                    --Kumar

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                    0
                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #17

                      Yes that's what I had in mind, without forgetting the main screen first.

                      Interested in AI ? www.idiap.ch
                      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                      K 2 Replies Last reply
                      0
                      • SGaistS SGaist

                        Yes that's what I had in mind, without forgetting the main screen first.

                        K Offline
                        K Offline
                        kumararajas
                        wrote on last edited by
                        #18

                        @SGaist Oh ya, I missed the main screen

                        So here is the code which I can do the test:

                        // Main screen
                        QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                        tpos = qt_screen->mapFromDevice(pos, s);
                        
                        // Subscreens
                        QList<QScreen*> screens = qt_screen->subScreens();
                        if (screens.size()) 
                        {
                            for (int i = 0; i < screens.size(); ++i) 
                            {
                                QScreen *screen = screens.at(i);
                                QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                                tpos = screen->mapFromDevice(pos, s);
                                break;
                            }
                        }
                        

                        Right?

                        --Kumar

                        1 Reply Last reply
                        0
                        • SGaistS SGaist

                          Yes that's what I had in mind, without forgetting the main screen first.

                          K Offline
                          K Offline
                          kumararajas
                          wrote on last edited by
                          #19

                          @SGaist Below the patch code, I see

                              QPoint tpos;
                              // Main screen
                              QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                              tpos = qt_screen->mapFromDevice(pos, s);
                          
                              // Sub screens
                              QList<QScreen*> screens = qt_screen->subScreens();
                              if (screens.size()) 
                              {
                                  for (int i = 0; i < screens.size(); ++i) 
                                  {
                                      QScreen *screen = screens.at(i);
                                      QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                                      tpos = screen->mapFromDevice(pos, s);
                                      break;
                                  }
                              }
                          
                              if (qt_last_x) {
                                   *qt_last_x = tpos.x();
                                   *qt_last_y = tpos.y();
                              }
                              QWSServer::mousePosition = tpos;
                              qwsServerPrivate->mouseState = state;
                          

                          We use the tpos and mouse the mousePosition just once. Even though, we have many subscreens, we just do it once.

                          Is this correct?

                          Should we not do this in a loop for all the screens?

                          Please let me know.

                          --Kumar

                          K 1 Reply Last reply
                          0
                          • K kumararajas

                            @SGaist Below the patch code, I see

                                QPoint tpos;
                                // Main screen
                                QSize s = QSize(qt_screen->deviceWidth(), qt_screen->deviceHeight());
                                tpos = qt_screen->mapFromDevice(pos, s);
                            
                                // Sub screens
                                QList<QScreen*> screens = qt_screen->subScreens();
                                if (screens.size()) 
                                {
                                    for (int i = 0; i < screens.size(); ++i) 
                                    {
                                        QScreen *screen = screens.at(i);
                                        QSize s = QSize(screen->deviceWidth(), screen->deviceHeight());
                                        tpos = screen->mapFromDevice(pos, s);
                                        break;
                                    }
                                }
                            
                                if (qt_last_x) {
                                     *qt_last_x = tpos.x();
                                     *qt_last_y = tpos.y();
                                }
                                QWSServer::mousePosition = tpos;
                                qwsServerPrivate->mouseState = state;
                            

                            We use the tpos and mouse the mousePosition just once. Even though, we have many subscreens, we just do it once.

                            Is this correct?

                            Should we not do this in a loop for all the screens?

                            Please let me know.

                            K Offline
                            K Offline
                            kumararajas
                            wrote on last edited by
                            #20

                            Looks like I am in a wrong direction.

                            I suspect "Transformed" driver is not having problem.

                            I think, it is "multi" screen driver is what not working good.

                            Because, when VNC option is selected, Transformed works food.
                            When LinuxFb is selected, Transformed works good.

                            When both are used, there lies the problem.

                            I guess, we may have to look at Multi Screen driver source code to see how it has been implemented.

                            Can you please point me to the right location?

                            Thanks,
                            Kumara

                            --Kumar

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                            0
                            • SGaistS Offline
                              SGaistS Offline
                              SGaist
                              Lifetime Qt Champion
                              wrote on last edited by
                              #21

                              I'd take a look a the qscreenmulti_qws.cpp file

                              Interested in AI ? www.idiap.ch
                              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                              K 2 Replies Last reply
                              0
                              • SGaistS SGaist

                                I'd take a look a the qscreenmulti_qws.cpp file

                                K Offline
                                K Offline
                                kumararajas
                                wrote on last edited by
                                #22

                                @SGaist Oh!
                                Any thing you found?

                                --Kumar

                                1 Reply Last reply
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                                • SGaistS SGaist

                                  I'd take a look a the qscreenmulti_qws.cpp file

                                  K Offline
                                  K Offline
                                  kumararajas
                                  wrote on last edited by
                                  #23

                                  @SGaist Later I gave a try with

                                  export QWS_DISPLAY="VNC:Transformed:Rot270"
                                  

                                  I dont know the magic behind this.

                                  In my LCD display UI, looks good. And even touch works well.

                                  And now, in the VNC client, Application was rotated. So, I used RealVNC client and rotated the screen to 270.
                                  With that, UI looks good and even operation works well.

                                  I dont know what magic behind the scene.

                                  But the problem I see is, display refresh in VNC client. The screen doesnt gets refreshed. There is a hug lag while updating the screen..

                                  I am totally confused now, to understand the problem.

                                  Based on your experience,
                                  Where do you see the problem?

                                  Thanks a lot for your immense support!

                                  --Kumar

                                  1 Reply Last reply
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                                  • SGaistS Offline
                                    SGaistS Offline
                                    SGaist
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #24

                                    90 and 270 are "complementary" meaning that 270 is equivalent to -90 so it might be that the position calculation were done wrong (or just not taking the angle in account correctly)

                                    Do you mean that with 90, the refreshing is done correctly on both but not the mouse handling and with 270, the refreshing is wrong but the mouse move are handled correctly ?

                                    Interested in AI ? www.idiap.ch
                                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    K 2 Replies Last reply
                                    0
                                    • SGaistS SGaist

                                      90 and 270 are "complementary" meaning that 270 is equivalent to -90 so it might be that the position calculation were done wrong (or just not taking the angle in account correctly)

                                      Do you mean that with 90, the refreshing is done correctly on both but not the mouse handling and with 270, the refreshing is wrong but the mouse move are handled correctly ?

                                      K Offline
                                      K Offline
                                      kumararajas
                                      wrote on last edited by
                                      #25

                                      @SGaist No. With both 90 or 270, I can see the mouse move is perfect. But the refreshing is not working good.

                                      --Kumar

                                      1 Reply Last reply
                                      0
                                      • SGaistS SGaist

                                        90 and 270 are "complementary" meaning that 270 is equivalent to -90 so it might be that the position calculation were done wrong (or just not taking the angle in account correctly)

                                        Do you mean that with 90, the refreshing is done correctly on both but not the mouse handling and with 270, the refreshing is wrong but the mouse move are handled correctly ?

                                        K Offline
                                        K Offline
                                        kumararajas
                                        wrote on last edited by kumararajas
                                        #26

                                        @SGaist Sam, any further thoughts?

                                        I don't want to give up. I want to fix this Qt bug. For sure, I will need your / Qt experts help.

                                        Thank you,
                                        Kumara

                                        --Kumar

                                        K 1 Reply Last reply
                                        0
                                        • K kumararajas

                                          @SGaist Sam, any further thoughts?

                                          I don't want to give up. I want to fix this Qt bug. For sure, I will need your / Qt experts help.

                                          Thank you,
                                          Kumara

                                          K Offline
                                          K Offline
                                          kumararajas
                                          wrote on last edited by
                                          #27

                                          Still no success so far.

                                          Any thoughts on how to handle this?

                                          Thank you!
                                          Kumara

                                          --Kumar

                                          1 Reply Last reply
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