Pixman Accessors

Soeren Sandmann sandmann at daimi.au.dk
Tue Jun 9 10:17:03 PDT 2009


Maarten Maathuis <madman2003 at gmail.com> writes:

> Have you benchmarked this? I know it wasn't fast, but if it becomes
> even (significantly) slower that's not very nice.  I'm not near a
> system where i can test this for the forseeable future.

I don't buy the performance argument. We are talking about software
compositing of data in video memory by the slow path in pixman where
both reads and writes are done with two indirect function calls per
pixel.

The new scheme uses the accessor functions to move the data to host
memory, then running whatever fast paths are available, then copying
back to video memory.

I would guess that the new scheme is faster, but I don't really care
if it isn't. The best you can hope for is "unusable, but benchmarks
show this is faster" vs. "unusable".


Soren


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