[Pixman] [PATCH 1/3] Move miTrapezoids() into fb as fbTrapezoids().
sandmann at cs.au.dk
Wed Oct 5 04:44:31 PDT 2011
Michel Dänzer <michel at daenzer.net> writes:
> On Die, 2011-10-04 at 15:52 -0700, Aaron Plattner wrote:
>> This caused a performance regression because previously, miTrapezoids
>> would render its mask image into a scratch pixmap and then perform the
>> final composite using a possibly-accelerated RENDER Composite call.
>> Now, fbTrapezoids does the final composite in software, leading to, for
>> example, http://www.nvnews.net/vbulletin/showthread.php?t=166698
>> Of course, I could simply copy the old miTrapezoids implementation into
>> our driver, but it seems hard to believe that our driver is the only one
>> that benefited from the "rasterize in software, composite in hardware"
>> behavior of the old code. Should I re-add miTrapezoids as a helper that
>> drivers can plug in when they want the old behavior, just revert this
>> change, or go the "only nvidia gets to go fast" copy & paste route?
> FWIW, EXA already had a copy of miTrapezoids before this change to avoid
> GPU<->CPU ping-pong (GPU clear, CPU rasterization, GPU composition).
Yes, and uxa inherited that. There were no open source users of
miTrapezoids() when I wrote the patch.
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