Re: [Mesa3d-dev] X renderer speedup (write_span_mono_pixmap optimization)

[Brian P. <br...@va...>]

Jeff Epler wrote:
> 
> I tried Keith's code this morning.  It appears to be the same speed
> as my original code.
> 
> I wanted to verify that it gives the same results as the old code, but
> chose a rather low-tech way to do it -- grab a screenshot with gimp from
> each version, and use the "difference" mode to find any differences.
> 
> The version I first compared against was actually Mesa 3.2-2 from
> RedHat 6.2, and I noticed something weird -- The background was
> cleared to RGB (0,4,0) rather than (0,0,0) in 3.4.1 + patch.  Is
> this just a bug that was fixed in the meantime?

What is your glClearColor() and what depth is your rendering window?
I seem to recall making a change to clear color months ago but I
don't remember the details.


> When I compare
> 3.4.1 vs 3.4.1 + patch, the results are identical in all pixels.

OK, I'll apply Keith's version of the patch.


> One question -- if we use a Mesa with this patch in XFree86 4.0 glx,
> will the optimization apply when not using hardware acceleration?

Yes.  The indirect GLX renderer will also benefit from this.

-Brian