Haruna: Performance issues on older and/or less powerful hardware

[Janet Blackquill]

Am Mi., 15. Dez. 2021 um 16:49 Uhr schrieb George Florea Banus
<georgefb899 at gmail.com>:
>
> Sorry, I messed up and didn't reply to the mailing list.
>
> On 15.12.2021 22:26, Janet Blackquill wrote:
> > Am Mi., 15. Dez. 2021 um 14:25 Uhr schrieb George Florea Banus
> > <georgefb899 at gmail.com>:
> >> Hello,
> >>
> >> I'm having some problems with playback stuttering
> >> on older and/or less powerful hardware (Intel i5-4590 3.30GHz, HD
> >> Graphics 4600),
> >> while in mpv (and VLC too) it plays smoothly.
> >> I'm rendering the video in a QOpenGLFramebufferObject
> >> (https://invent.kde.org/multimedia/haruna/-/blob/master/src/mpvobject.cpp).
> >>
> >> I'm thinking the problem could be what Jean-Baptiste Kempf mentions in a
> >> talk about VLC and Qt.
> >> The important part starts at 40:36 and ends at 42:30
> >> https://youtu.be/P1qMAupb2_Y?t=2436
> >> Basically he says that Qt's rendering loop "doesn't work for video".
> >> VLC (the new QML version) works around this by having two windows:
> >> a native window for the video and one for QML and making them act as one.
> >>
> >> I would like to avoid that.
> > Is there a reason why?
>
> I feel like it would complicate things a lot. Resizing, moving and also
> stacking them so they behave like one window.

The positioning stuff for this sort of usecase is mostly handled by
the windowing systems; Wayland via subsurfaces, and X11 via something
(transient parents?).

I don't recall what exactly you need to do in Qt to achieve this
behaviour, though. Someone else could clarify here.

> >> Is there anything I can do to so that the playback is on par with mpv?
> >>
> >> ----
> >>
> >> Here is a report I made on mpv's issue tracker with more details
> >> https://github.com/mpv-player/mpv/issues/9417