[vlc-devel] [PATCH 1/4] mmal: update the code from the one actually used in Raspbian

[Rémi Denis-Courmont]

Le lauantaina 18. tammikuuta 2020, 7.18.54 EET Steve Lhomme a écrit :
> This is a hack to know which display id is used when going in full-screen.

It won't work anyway. There's no guarantees that the Qt plugin is providing 
the window, or if it is, how it counts displays.

> It's either HDMI0 or HDMI1 and the display module needs to know that to go
> in the right mode.

You're assuming a specific hardware version and Qt back-end there. I don't know 
if Raspian patched Qt to guarantee that Qt provides the same numbers as XRR 
(on local display). But it's not generally valid. E.g., I've been using Ubuntu 
on rPI3 since Raspian can't be bothered to support 64-bits, and they AFAIK, 
they just ship normal Qt, not some rPI-specific fork of it.

> That corresponds to the Qt variable that can use a
> different display when going in full-screen. I suppose it takes the widget
> with the VLC window and send it to the other screen. But the display module
> isn't told about it.

The display module can find what subrectangle of the window is visible on each 
output by monitoring the window and output events. It's just not "supposed" to 
care. E.g. what will it do if two active outputs are clones?

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