[Mesa-dev] [PATCH v3 3/6] gallium: add API for setting window rectangles

[Ilia Mirkin]

On Mon, Jun 13, 2016 at 10:45 AM, Brian Paul <brianp at vmware.com> wrote:
> On 06/12/2016 12:36 AM, 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>
>> ---
>>   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
>
>
> What about clearing?
>
> As-is, our pipe_context::clear() function doesn't support scissors or color
> channel masking.  Is it now supposed to support window rects? That could put
> a new burden on drivers.  Some drivers might have to fallback to drawing a
> list of rects.  The 'exclusive' mode seems tricky.  That's the kind of thing
> the state tracker has done for us so far.  Or maybe we need a new util
> helper for converting window rect clears into quad drawing.
>
> Similar question for clear_render_target() and clear_depth_stencil().

Nope. Clears ignore the window rects, like they ignore scissors and
everything else. The state tracker falls back to the clear_with_quads
path if any window rectangles are set.

>
>
>
>> +  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 *
>> );
>> +
>
>
> I realize you're just following other examples, but I think
> set_window_rectangles would be nicer.  I'd be in favor of renaming
> set_viewport_states to set_viewports someday too.

Sure, will do.

>
>
>
>>      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) */
>>
>