Stabilizing wl_scaler protocol extension

[Pekka Paalanen]

Hi,

wl_scaler has been sitting in Weston for quite some time now:
http://cgit.freedesktop.org/wayland/weston/tree/protocol/scaler.xml

I would like to collect comments and opinions on the protocol extension:
- Is it ready?
- Are the interfaces ok? As in, have a wl_viewport created for a
  wl_surface, instead of having wl_surface argument on a global request.
- Are the names ok?
- Should wl_viewport.set be removed as completely redundant?
- Do we care about maintaining compatibility with the current wl_scaler
  protocol, when moving it into Wayland?

Obviously, if we change anything, it won't be compatible with the
current version.

My goal is to move wl_scaler or equivalent into the Wayland repository.
That effort is now tracked at:
https://bugs.freedesktop.org/show_bug.cgi?id=83918

(Also that I wouldn't forget again, as I already did. :-p)

I don't know how widely or little it has been used so far, so simply
pointing out projects that already use it would be nice, too.

Originally, I was waiting for the Presentation queueing to mature a bit
before declaring wl_scaler as stable, because queueing seemed to
require a split in the scaler state. That split is there now, and while
I haven't really worked on Presentation for a long time, I do not see
further changes needed. And even this split was introduced in a
backwards compatible manner.

I don't have a deadline for this, but now would be a good time to bring
out all your critique about the wl_scaler/wl_viewport extension on the
record. :-)


Thanks,
pq