QWS VNC doesn't work on Portrait mode

[kumararajas]

@SGaist Ok Sam. Do you see any way to fix this problem?

Thank you.

[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)

[kumararajas]

@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?

[SGaist]

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

[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..

[kumararajas]

No success yet!

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

[SGaist]

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

[kumararajas]

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.

[kumararajas]

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

Thanks,
Kumara

[kumararajas]

@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

[SGaist]

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

[kumararajas]

@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?

[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.

[kumararajas]

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

[SGaist]

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

[kumararajas]

@SGaist Oh!
Any thing you found?

[kumararajas]

@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!

[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 ?

[kumararajas]

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

[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