[Mesa-dev] [PATCH] gallium: add API for setting window rectangles

[Nicolai Hähnle]

On 11.06.2016 21:14, Ilia Mirkin wrote:
> Window rectangles apply to all framebuffer operations, either in
> inclusive or exclusive mode. They may also be specified as part of a
> blit operation.
>
> In exclusive mode, any fragment inside any of the specified rectangles
> will be discarded.
>
> In inclusive mode, any fragment outside every rectangle will be
> discarded.
>
> The no-op state is to have 0 rectangles in exclusive mode.
>
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>
> Wanted to get some early feedback on the interface, while I go around adding pipe caps and the state tracker code (which is easy but a little time-consuming).

The API makes sense to me.

Cheers,
Nicolai

>
> This is for GL_EXT_window_rectangles.
>
>   src/gallium/docs/source/context.rst  | 15 ++++++++++++---
>   src/gallium/include/pipe/p_context.h |  5 +++++
>   src/gallium/include/pipe/p_state.h   |  6 ++++++
>   3 files changed, 23 insertions(+), 3 deletions(-)
>
> diff --git a/src/gallium/docs/source/context.rst b/src/gallium/docs/source/context.rst
> index 3a45f40..667d9a2 100644
> --- a/src/gallium/docs/source/context.rst
> +++ b/src/gallium/docs/source/context.rst
> @@ -79,6 +79,15 @@ 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_window_rectangle_states`` sets the window rectangles to be
> +  used for rendering, as defined by GL_EXT_window_rectangles. There
> +  are two modes - include and exclude, which define whether the
> +  supplied rectangles are to be used for including fragments or
> +  excluding them. All of the rectangles are ORed together, so in
> +  exclude mode, any fragment inside any rectangle would be culled,
> +  while in include mode, any fragment outside all rectangles would be
> +  culled. xmin/ymin are inclusive, while xmax/ymax are exclusive (same
> +  as scissor states above).
>   * ``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``.
> @@ -492,9 +501,9 @@ This can be considered the equivalent of a CPU memcpy.
>
>   ``blit`` blits a region of a resource to a region of another resource, including
>   scaling, format conversion, and up-/downsampling, as well as a destination clip
> -rectangle (scissors). It can also optionally honor the current render condition
> -(but either way the blit itself never contributes anything to queries currently
> -gathering data).
> +rectangle (scissors) and window rectangles. It can also optionally honor the
> +current render condition (but either way the blit itself never contributes
> +anything to queries currently gathering data).
>   As opposed to manually drawing a textured quad, this lets the pipe driver choose
>   the optimal method for blitting (like using a special 2D engine), and usually
>   offers, for example, accelerated stencil-only copies even where
> diff --git a/src/gallium/include/pipe/p_context.h b/src/gallium/include/pipe/p_context.h
> index 9d7a8eb..0ea18c7 100644
> --- a/src/gallium/include/pipe/p_context.h
> +++ b/src/gallium/include/pipe/p_context.h
> @@ -274,6 +274,11 @@ struct pipe_context {
>                                  unsigned num_scissors,
>                                  const struct pipe_scissor_state * );
>
> +   void (*set_window_rectangle_states)( struct pipe_context *,
> +                                        boolean include,
> +                                        unsigned num_rectangles,
> +                                        const struct pipe_scissor_state * );
> +
>      void (*set_viewport_states)( struct pipe_context *,
>                                   unsigned start_slot,
>                                   unsigned num_viewports,
> diff --git a/src/gallium/include/pipe/p_state.h b/src/gallium/include/pipe/p_state.h
> index 396f563..9c69355 100644
> --- a/src/gallium/include/pipe/p_state.h
> +++ b/src/gallium/include/pipe/p_state.h
> @@ -69,6 +69,7 @@ extern "C" {
>   #define PIPE_MAX_VIEWPORTS        16
>   #define PIPE_MAX_CLIP_OR_CULL_DISTANCE_COUNT 8
>   #define PIPE_MAX_CLIP_OR_CULL_DISTANCE_ELEMENT_COUNT 2
> +#define PIPE_MAX_WINDOW_RECTANGLES 8
>
>
>   struct pipe_reference
> @@ -710,6 +711,11 @@ struct pipe_blit_info
>      boolean scissor_enable;
>      struct pipe_scissor_state scissor;
>
> +   /* Window rectangles can either be inclusive or exclusive. */
> +   boolean window_rectangle_include;
> +   unsigned num_window_rectangles;
> +   struct pipe_scissor_state window_rectangles[PIPE_MAX_WINDOW_RECTANGLES];
> +
>      boolean render_condition_enable; /**< whether the blit should honor the
>                                       current render condition */
>      boolean alpha_blend; /* dst.rgb = src.rgb * src.a + dst.rgb * (1 - src.a) */
>