[Mesa-dev] [PATCH 0.5/5] i965/gen9/fast-clear: Handle linear???SRGB conversion

[Pohjolainen, Topi]

On Tue, Dec 01, 2015 at 05:27:19PM +0000, Neil Roberts wrote:
> "Pohjolainen, Topi" <topi.pohjolainen at intel.com> writes:
> 
> >> +   /* Handle linear???SRGB conversion */
> >> +   if (brw->ctx.Color.sRGBEnabled &&
> >> +       _mesa_get_srgb_format_linear(mt->format) != mt->format) {
> >
> > Patch five disables fast clear for single-sampled if
> > brw->ctx.Color.sRGBEnabled is set. How about something like this:
> >
> >          /* Fast clears are disabled for single-sampled buffers when
> >           * sRGBEnabled is set.
> >           */
> >          assert(mt->num_samples > 1);
> 
> That could be a good idea but the thing that makes me a little
> uncomfortable is that it should actually be fine to do a fast clear with
> GL_FRAMEBUFFER_SRGB enabled and it's only actually a problem when it
> comes to rendering. Eg, if we didn't have patch 5 you could clear with
> SRGB enabled and then disable it before rendering something else and
> everything would be fine.
> 
> Patch 5 is really only an optimisation which implements the heuristic
> that if GL_FRAMEBUFFER_SRGB is enabled when you do the clear then it's
> very likely that it's still going to be enabled when you render
> something else. The patch isn't a hard requirement because without it it
> would just do the resolve before rendering so it would still work, but
> it's just a bit wasteful.
> 

Thanks for explaining again. So the assert should go to patch five if
anywhere. This patch is:

Reviewed-by: Topi Pohjolainen <topi.pohjolainen at intel.com>