Qt embedded screen rotation inside app

Question

In our target device, we run our QtE app with -qws argument. To rotate the screen, we specify \"-display transformed:rot90\" as the app argument and it works well.

H

Answer 1

Contrary to other qt documentation, documentation for the embedded part of qt is indeed poor. After few days of fiddling with it, I finally managed to solve it.

First thing to do is to compile the library with -qt-gfx-transformed option (along with whatever you need).

Then you compile your application, and start it with the option you already used to activate the transformation driver. I actually started like this :

export QWS_DISPLAY=Transformed:Rot90:0
./app

As a test, I implemented this, to test whether the rotation works :

class X : public QObject
{
  Q_OBJECT
public :
  X() :
    QObject()
  {
    QTimer *t = new QTimer( this );
    connect( t, SIGNAL(timeout()), this, SLOT(OnTimerEvent()));
    t->start( 2500 );
  }

public slots :
  inline void OnTimerEvent()
  {
    static int v = 0;
    ++v;

    QWSDisplay::setTransformation(v%4);

    std::cout<<v<<std::endl;
  }
};

So, in the timer slot, I am changing the orientation with QWSDisplay::setTransformation function.