[Mesa-dev] [PATCH 3/4] st/mesa: Add support for ARB_post_depth_coverage

[Lyude Paul]

On Tue, 2017-05-23 at 15:24 -0400, Ilia Mirkin wrote:
> On Tue, May 23, 2017 at 3:19 PM, Ilia Mirkin <imirkin at alum.mit.edu>
> wrote:
> > On Tue, May 23, 2017 at 3:00 PM, Lyude <lyude at redhat.com> wrote:
> > > Signed-off-by: Lyude <lyude at redhat.com>
> > > ---
> > >  src/mesa/state_tracker/st_extensions.c     | 1 +
> > >  src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 6 +++++-
> > >  2 files changed, 6 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/src/mesa/state_tracker/st_extensions.c
> > > b/src/mesa/state_tracker/st_extensions.c
> > > index f3db702..7674156 100644
> > > --- a/src/mesa/state_tracker/st_extensions.c
> > > +++ b/src/mesa/state_tracker/st_extensions.c
> > > @@ -600,6 +600,7 @@ void st_init_extensions(struct pipe_screen
> > > *screen,
> > >        {
> > > o(ARB_occlusion_query2),             PIPE_CAP_OCCLUSION_QUERY    
> > >               },
> > >        {
> > > o(ARB_pipeline_statistics_query),    PIPE_CAP_QUERY_PIPELINE_STAT
> > > ISTICS        },
> > >        {
> > > o(ARB_point_sprite),                 PIPE_CAP_POINT_SPRITE       
> > >               },
> > > +      {
> > > o(ARB_post_depth_coverage),          PIPE_CAP_POST_DEPTH_COVERAGE
> > >               },
> > >        {
> > > o(ARB_query_buffer_object),          PIPE_CAP_QUERY_BUFFER_OBJECT
> > >               },
> > >        { o(ARB_robust_buffer_access_behavior),
> > > PIPE_CAP_ROBUST_BUFFER_ACCESS_BEHAVIOR   },
> > >        {
> > > o(ARB_sample_shading),               PIPE_CAP_SAMPLE_SHADING     
> > >               },
> > > diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > > b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > > index 76cd4dc..e038206 100644
> > > --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > > +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > > @@ -6376,9 +6376,13 @@ st_translate_program(
> > >     }
> > > 
> > >     if (procType == PIPE_SHADER_FRAGMENT) {
> > > -      if (program->shader->Program-
> > > >info.fs.early_fragment_tests)
> > > +      if (program->shader->Program-
> > > >info.fs.early_fragment_tests) {
> > >           ureg_property(ureg,
> > > TGSI_PROPERTY_FS_EARLY_DEPTH_STENCIL, 1);
> > > 
> > > +         if (program->shader->Program-
> > > >info.fs.post_depth_coverage)
> > > +            ureg_property(ureg,
> > > TGSI_PROPERTY_FS_POST_DEPTH_COVERAGE, 1);
> > 
> > From the spec,
> > 
> > "Use of this feature implicitly enables early fragment tests."
> > 
> > However I see nothing that would force early_fragment_tests to be
> > enabled when post_depth_coverage is enabled.
> 
> A decision point here, btw, is whether this is up to the frontend or
> the backend. My thought is that it's up to the frontend to flip both
> on rather than the backend to know that early frag tests are a || b
> ||
> c || d || ... .
Yeah, that was my thought as well. Toplevel gl plumbing seems like a
better place for this then gallium

-- 
Cheers,
	Lyude