[vlc-devel] [PATCH 14/16] video_output: rename ambiguous refresh flag to redisplay_needed

[Alexandre Janniaux]

Hi,

On Sat, Oct 17, 2020 at 05:20:07PM +0300, Rémi Denis-Courmont wrote:
> Le lauantaina 17. lokakuuta 2020, 16.41.43 EEST Alexandre Janniaux a écrit :
> > Hi,
> >
> > I'm not sure why the renaming is needed, refresh is both for non
> > compositing window manager (see xrefresh)
>
> Not really. It's primarily there to refresh OSD during pause or with a slow
> frame rate.

Indeed, you're right, but that doesn't really invalidate my point.

> If the vout display plugin is not composited, it can (and should) hold the
> last picture and redraw it upon a damage event or a change of picture
> placement. There are no needs for the core to know about that. In fact, to
> handle partial damage in optimised fashion, you really don't want the core to
> be involved.
>
> Refreshing the display in the core is just legacy bug compatibility.

Sure, this is also tracked by your ticket https://trac.videolan.org/vlc/ticket/17700
and/or (if it does not match, I'm not sure to understand the ticket like this) more
generally the absence of real video clock signal usable in the video output to
resample the data video/spu clocks accordingly, leading to this arbitrary value.

But then, to fix my argument in this context, redisplay is not even a «correct»
wording since it's made for case where the OSD/SPU would actually change (like,
OSD being displayed earlier than the next frame, reusing the previous frame).

Regards,
--
Alexandre Janniaux
Videolabs