[Bug 94816] Nearest neighbor scaling?

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=94816

--- Comment #9 from Chris Wilson <chris at chris-wilson.co.uk> ---
(In reply to nw9165-3201 from comment #8)
> (In reply to Chris Wilson from comment #5)
> > but you can't set it (unless I am blind).
> 
> Would it make sense to submit a issue/feature request for this?

It's underway: https://patchwork.freedesktop.org/patch/79564/

> > The attached should automatically use nearest neighbour with the panel
> > fitter.
> 
> Thank you. Sorry for sounding stupid again, but could you please tell me how
> I could test this when running Ubuntu for example?

You would use xrandr --output DP1 --mode 3840x2160 --scale-from 1920x1080 (with
an updated xrandr).

> And would this also allow playing 3D games with nearest neighbor scaling
> (i.e. running a game natively at 1920x1080 on a 3840x2160 display)?

In theory, yes. In practice, I imagine the games will be querying the list of
monitor resolutions and do something different. Ideally, the games would do the
upscaling themselves (that also allows for something like the UI overlay being
high definition for sharp text, whilst upscaling the heavy content). Doing the
upscaling late in the chain incurs an additional step (that is less likely to
be as efficient as doing it earlier in the client).

With the panel fitter it is even easier as we just use xrandr --output eDP1
--mode 1920x1080 and the hardware scales automatically to the native resolution
of the panel from the source buffer (but we still want to ideally disable the
filter here even though the hardware should be using a higher quality filter
than bilinear).

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20160404/5f37ea5d/attachment.html>