Re: [Dri-devel] R100 GL_ATI_texture_env_combine3

[Ian R. <id...@us...>]

Martin Spott wrote:
> Ian, now that you've merged in the software support for combine3 from the
> Mesa trunk, I'm trying to get it working in hardware on R100 with texmem
> (impatient as I am ;) ).
> 
> 
> Where do I find at least a short explanation on the effect this patch should
> show to me (to the user) ? The only impression I have after a short test is
> decreased frame rate in FlightGear under certain conditions. I'm pretty
> shure this is not your primary intention with this patch  ;-)
> So obviously this patch is considered to improve something else that
> FlightGear das not benefit from,

Which patch do you mean?  Do you mean the patch in Leif's e-mail in this 
thread or the patch in his e-mail with the "[PATCH] texmem-0-0-1 branch" 
subject?  Or do you mean something else? :)

The patch in this thread should not have any impact on performance.  It 
adds a couple of extra combine modes to the list in 
ARB_texture_env_combine.  The patch in the other thread fixes some bugs 
that can lead to texture corruption when there are multiple active GL 
contexts.  It's possible that could effect performance, but only in the 
case of multiple active contexts.

That would be easy enough to verify with oprofile.  Just take a profile 
with and without the patch.  In order to get profile data on the GL 
driver, do this:

oprofpp -l /usr/X11R6/lib/modules/dri/radeon_dri.so

Or whatever your driver is.

If more time shows up in any of the functions in 
lib/GL/mesa/src/drv/common/texmem.c or in the texture upload functions 
in the driver, then you can blame the patch. :)  Either way, it would be 
interesting to see profiles of common apps.