[Mesa-dev] [PATCH v4 2/3] mesa/st: enable EXT_sRGB_write_control for Gallium drivers that support it

[Gert Wollny]

Am Dienstag, den 30.10.2018, 16:52 -0400 schrieb Ilia Mirkin:

[snip]
> > >     }
> > >  #endif
> > > 
> > > +   extensions->EXT_sRGB_write_control =
> > > +         screen->is_format_supported(screen,
> > > PIPE_FORMAT_B8G8R8A8_SRGB,
> > > +                                     PIPE_TEXTURE_2D, 0, 0,
> > > +                                     (PIPE_BIND_DISPLAY_TARGET |
> > > +                                      PIPE_BIND_RENDER_TARGET));
> > 
> > 
> > This is kinda a hack because DISPLAY_TARGET has nothing to do with
> > sRGB. sRGB is a 3D/framebuffer feature, unrelated to the window
> > system. The sRGB property of the format is private within the
> > application and is not visible outside of it. The window system
> > doesn't care what is and isn't sRGB. I think you are just hiding a
> > bug in your driver.
> 
> Yeah, it's unclear to me what GL_EXT_sRGB_write_control does beyond
> using a sRGB framebuffer format for a FBO. Either you can handle that
> format or you can't...
> 
This is actually just some copy-paste problem, i.e. I took what is used
in st_manager.c:st_framebuffer_create to check for sRGB support of the
sepcific format used there, adjusted the pipe format to a defined
format and cleaned the sample parameters. If this is not needed for
some other reason, then I'll just drop it.

Best, 
Gert