[Mesa-dev] [PATCH 1/2] mesa: Implement ARB_texture_filter_minmax

[Ian Romanick]

On 11/14/2017 02:54 PM, Scott D Phillips wrote:
> This extension provides a new texture and sampler parameter
> (TEXTURE_REDUCTION_MODE_ARB) which allows applications to produce
> a filtered texel value by computing a component-wise minimum (MIN)
> or maximum (MAX) of the texels that would normally be averaged.
> ---
> CTS tests KHR-GL45.texture_filter_minmax_tests.* need a little TLC to
> pass with this series. Details in VK-GL-CTS issue: 849
> 
>  src/mesa/main/attrib.c           |  4 ++++
>  src/mesa/main/extensions_table.h |  1 +
>  src/mesa/main/formatquery.c      | 10 ++++++++++
>  src/mesa/main/mtypes.h           |  2 ++
>  src/mesa/main/samplerobj.c       | 37 +++++++++++++++++++++++++++++++++++++
>  src/mesa/main/texobj.c           |  2 ++
>  src/mesa/main/texobj.h           |  2 +-
>  src/mesa/main/texparam.c         | 33 +++++++++++++++++++++++++++++++++
>  8 files changed, 90 insertions(+), 1 deletion(-)
> 

[lots of stuff trimmed]

> diff --git a/src/mesa/main/extensions_table.h b/src/mesa/main/extensions_table.h
> index 5b66e7d30d..c51ad80742 100644
> --- a/src/mesa/main/extensions_table.h
> +++ b/src/mesa/main/extensions_table.h
> @@ -146,6 +146,7 @@ EXT(ARB_texture_env_combine                 , ARB_texture_env_combine
>  EXT(ARB_texture_env_crossbar                , ARB_texture_env_crossbar               , GLL,  x ,  x ,  x , 2001)
>  EXT(ARB_texture_env_dot3                    , ARB_texture_env_dot3                   , GLL,  x ,  x ,  x , 2001)
>  EXT(ARB_texture_filter_anisotropic          , ARB_texture_filter_anisotropic         , GLL, GLC,  x ,  x , 2017)
> +EXT(ARB_texture_filter_minmax               , ARB_texture_filter_minmax              , GLL, GLC,  x ,  x , 2017)

Is this right?  The extension says OpenGL 3.3 is required, and we don't
(until Marek is done) do OpenGL 3.3 compatibility profile.

>  EXT(ARB_texture_float                       , ARB_texture_float                      , GLL, GLC,  x ,  x , 2004)
>  EXT(ARB_texture_gather                      , ARB_texture_gather                     , GLL, GLC,  x ,  x , 2009)
>  EXT(ARB_texture_mirror_clamp_to_edge        , ARB_texture_mirror_clamp_to_edge       , GLL, GLC,  x ,  x , 2013)
> diff --git a/src/mesa/main/texparam.c b/src/mesa/main/texparam.c
> index 4a0f61eda8..94883b2210 100644
> --- a/src/mesa/main/texparam.c
> +++ b/src/mesa/main/texparam.c
> @@ -630,6 +630,25 @@ set_tex_parameteri(struct gl_context *ctx,
>        }
>        goto invalid_pname;
>  
> +   case GL_TEXTURE_REDUCTION_MODE_ARB:
> +      if (ctx->Extensions.ARB_texture_filter_minmax) {
> +

Extra blank line here should be deleted.

> +         if (!_mesa_target_allows_setting_sampler_parameters(texObj->Target))
> +            goto invalid_enum;
> +
> +         if (texObj->Sampler.ReductionMode == params[0])
> +            return GL_FALSE;
> +         if (params[0] == GL_MIN ||
> +             params[0] == GL_MAX ||
> +             params[0] == GL_WEIGHTED_AVERAGE_ARB) {
> +            flush(ctx);
> +            texObj->Sampler.ReductionMode = params[0];
> +            return GL_TRUE;
> +         }
> +         goto invalid_param;
> +      }
> +      goto invalid_pname;
> +
>     default:
>        goto invalid_pname;
>     }