[Mesa-dev] [PATCH 08/19] gallium: add set_tess_state to configure default tessellation parameters

[Roland Scheidegger]

Seems a bit awkward that you have to set such state separately. I don't
know much about how this is supposed to work though, some quick grep
says these parameters are used when there's no tessellation control
shader, so I guess that's why it is separate state.
How does that actually work in hw, can you just switch tesselation
control shaders off or do you have to provide some kind of a default
tesselation ctrl shader?

Roland

Am 02.05.2015 um 22:16 schrieb Ilia Mirkin:
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>  src/gallium/docs/source/context.rst  | 5 +++++
>  src/gallium/include/pipe/p_context.h | 4 ++++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/src/gallium/docs/source/context.rst b/src/gallium/docs/source/context.rst
> index 5861f46..0908ee7 100644
> --- a/src/gallium/docs/source/context.rst
> +++ b/src/gallium/docs/source/context.rst
> @@ -79,6 +79,11 @@ objects. They all follow simple, one-method binding calls, e.g.
>    should be the same as the number of set viewports and can be up to
>    PIPE_MAX_VIEWPORTS.
>  * ``set_viewport_states``
> +* ``set_tess_state`` configures the default tessellation parameters:
> +  * ``default_outer_level`` is the default value for the outer tessellation
> +    levels. This corresponds to GL's ``PATCH_DEFAULT_OUTER_LEVEL``.
> +  * ``default_inner_level`` is the default value for the inner tessellation
> +    levels. This corresponds to GL's ``PATCH_DEFAULT_INNER_LEVEL``.
>  
>  
>  Sampler Views
> diff --git a/src/gallium/include/pipe/p_context.h b/src/gallium/include/pipe/p_context.h
> index 74c2f2f..afc5d7b 100644
> --- a/src/gallium/include/pipe/p_context.h
> +++ b/src/gallium/include/pipe/p_context.h
> @@ -231,6 +231,10 @@ struct pipe_context {
>                               unsigned start_slot, unsigned num_views,
>                               struct pipe_sampler_view **);
>  
> +   void (*set_tess_state)(struct pipe_context *,
> +                          float default_outer_level[4],
> +                          float default_inner_level[2]);
> +
>     /**
>      * Bind an array of shader resources that will be used by the
>      * graphics pipeline.  Any resources that were previously bound to
>