Comment 15 for bug 883319

http://patchwork.freedesktop.org/patch/6217/
http://patchwork.freedesktop.org/patch/6209/
I like the much more the approach in the above, as it tries to harness whatever the benefits claimed by adherents of mouse-bound check, may be.

I noticed the comment 'v2: Since crtc_bounds() is called a lot ...' means that the crtc_bounds() is called several times perhaps by mouse bound check code.
and speculate if that the reason for the alternate approach of disabling bound checking if panning is configured ?
am seeing code on
http://cgit.freedesktop.org/xorg/xserver/tree/randr/rrcrtc.c

I was wondering if the compute once, query many paradigm can be employed here.
as the crtc bounds change only when some event changes the screen size.
so crtc_bounds() may return a pre-computed bound per CRTC
and maybe a crtc_bounds_compute() is invoked to recompute only when the pre-computation has become stale.

Also, I just wish to point out, while its nice to fix panning and scaling together, it is not necessary. The use cases for those needing scaling fixed may be different, and can be incrementally fixed with another patch and bug report.

please ignore, if I don't make sense, as I'm just a just user, not developer.