Intel modesetting and tearing

[Christian Weisgerber]

I recently switched from an obsolescent Radeon card to the built-in
Intel HD Graphics P4600 with i915kms.ko and the modesetting driver.
That works fine, but there is very noticeable tearing whenever
something moves on-screen.  If you google for it, you'll find plenty
of complaints on Linux, so this is not a FreeBSD issue.

For MPlayer, replacing the default Xvideo with GL video output (-vo gl)
eliminates tearing.

And as I found out just today and quite by accident, in Firefox
toggling layers.acceleration.force-enabled to true will also eliminate
all tearing, whether from soft-scrolling or when playing YouTube
videos.  Hallelujah!

-- 
Christian "naddy" Weisgerber                          naddy at mips.inka.de