[Interest] iOS and openGL

[maitai]

Hi,

I have a QWidget app running on many platforms including iOS, using 
QGraphicsScene/View, Qt 5.15.2. The scene can contains many items, be 
rotated, etc.

We enable openGL QGraphicsview's viewport as it is stated in the 
documentation, i.e.

         QOpenGLWidget *gl = new QOpenGLWidget();
         QSurfaceFormat format;
         format.setSamples(4);
         gl->setFormat(format);
         setViewport(gl);

That works pretty well on all platforms and improves the performances, 
except on iOS (tested on iOS 14), where it is exactly the opposite: all 
become very very slow even in not complicated situations.

Is there something we can do to about that?

I know openGL is deprecated on iOS (replaced by Metal) does Qt supports 
that?

Thanks
Philippe.