wl_scaler (Re: wayland-devel Digest, Vol 34, Issue 44)

[Pekka Paalanen]

On Mon, 22 Jul 2013 18:11:54 +0800
Juan Zhao <juan.j.zhao at linux.intel.com> wrote:

> Hi pq,
> 
> On Mon, 15 Jul 2013 09:14:36 -0700
> wayland-devel-request at lists.freedesktop.org wrote:
> 
> > On Sat, 13 Jul 2013 11:34:03 +0000
> > "Wu, Zhiwen" <zhiwen.wu at intel.com> wrote:
> > 
> > > Hi pq,
> > > I didn't meet you at the IRC today for the time zone issue. So I
> > > send this mail. Our team are using subsurface to display the video
> > > within application UI. It works fine, but there is a common
> > > requirement on the video playback case, that is scaling. We would
> > > like to extend subsurface interface to support scaling the buffer
> > > on compositor side, instead of client side. What is your opinion
> > > about this? 
> > 
> > Hi,
> > 
> > I already had a first go on that a while back:
> > http://lists.freedesktop.org/archives/wayland-devel/2013-April/008927.html
> 
> This sounds interesting. And I just saw the protocol part here, is
> there any further implementation for this wl_scaler implementation?

Hi Juan,

no, not yet, it was just a protocol RFC to get an idea. I may have
few changes to it not posted to the list, but I won't get to them
until next week. And the interaction with the surface/output scale
(HiDPI) really needs to be figured out.

I don't mind if someone takes a shot at this, since I'm still away
for a week, and uncertain of my immediately following schedule.

I'm not aware of anyone else working on it, but then I have been
pretty ignorant of Wayland discussions in the recent weeks.


Thanks,
pq

> > Notice, how it is not a wl_subsurface addition, but an independent
> > extension. This way scaling and cropping can be applied to all
> > wl_surfaces, not just sub-surfaces, and it is independent of
> > sub-surface support.
> > 
> > I would strongly suggest to go through that thread and see my and
> > Daniel Stone's replies to the comments. There were quite some
> > differing opinions on how it should work. It would be nice to hear,
> > how my proposal fits your use cases.zjy
> > 
> > A new, unexplored issue is how it will interact with the hidpi
> > support.