[Interest] What's up with Qt's graphic stack (6.2.1) (and WebEngine)?

[Allan Sandfeld Jensen]

On Mittwoch, 24. November 2021 12:24:23 CET Nils Jeisecke wrote:
> Thanks for your response Allan.
> 
> On Tue, Nov 23, 2021 at 4:28 PM Allan Sandfeld Jensen <kde at carewolf.com> 
wrote:
> > We only support two backends in WebEngine currently, either WGL OpenGL or
> > the software backend. The software backend should work just fine though.
> > If you have any other QSG backend than OpenGL, it should automatically be
> > used, but you can also force it by selecting the software QSG backend or
> > using the chromium flag --disable-gpu.
> 
> Looks like overriding the renderer with
> QQuickWindow::setGraphicsApi(QSGRendererInterface::Software) *after*
> calling QtWebEngineQuick::initialize() seems to activate software
> rendering in Chromium. However, performance with Video (JITSI in my
> use case) is subpar :-( Any plans to enable Hardware Acceleration in
> Chromium with the "native" RHI backends (D3D11, metal)? Or is this
> technically imbossible (due to Chromium limitations)?
> 
We are planning to do that, but it is somewhat complicated. The QQuickWidget 
we use, only support OpenGL and Software in Qt 6.2, and there is no other 
QRHIWidget available or planned. We will be trying with a QWindow approach for 
6.3 or 6.4.

Another issue is that Chrome itself is still using OpenGL, on Windows using 
ANGLE, which Qt removed support for :/ 

Perhaps we can run QtWebEngine under ANGLE and the rest of Qt under D3D, but 
it is still at a research stage, and we are low on manpower.

So it is definitely something we would like to get working, but there are many 
pieces not fitting together at the moment.

Best regards
Allan