[Mesa-dev] [PATCH 2/6] mesa: wire up InvalidateSubFramebuffer

[Ian Romanick]

On 12/11/18 2:50 PM, Rob Clark wrote:
> Signed-off-by: Rob Clark <robdclark at gmail.com>
> ---
>  src/mesa/main/dd.h       |  3 +++
>  src/mesa/main/fbobject.c | 34 +++++++++++++++++++++++++++++++++-
>  2 files changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/src/mesa/main/dd.h b/src/mesa/main/dd.h
> index 1214eeaa474..c7112677223 100644
> --- a/src/mesa/main/dd.h
> +++ b/src/mesa/main/dd.h
> @@ -786,6 +786,9 @@ struct dd_function_table {
>                             GLbitfield mask, GLenum filter);
>     void (*DiscardFramebuffer)(struct gl_context *ctx, struct gl_framebuffer *fb,
>                                struct gl_renderbuffer_attachment *att);
> +   void (*DiscardSubFramebuffer)(struct gl_context *ctx, struct gl_framebuffer *fb,
> +                                 struct gl_renderbuffer_attachment *att, GLint x,
> +                                 GLint y, GLsizei width, GLsizei height);

After looking at the rest of the series... I wonder if some higher layer
should be responsible for detecting the case where the subrect size of
the DiscardSubFramebuffer is the size of the entire attachment (which
may be different than the renderable size of the framebuffer) and call
DiscardFramebuffer instead.  It seems like many implementations won't do
anything for DiscardSubFramebuffer but will do something for
DiscardFramebuffer.

Maybe just leave a note in discard_sub_framebuffer so that the first
person working on a driver that would benefit from this will implement it?

>  
>     /**
>      * \name Functions for GL_ARB_sample_locations
> diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
> index f931e8f76b1..8ef5eb747c0 100644
> --- a/src/mesa/main/fbobject.c
> +++ b/src/mesa/main/fbobject.c
> @@ -4699,12 +4699,41 @@ discard_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb,
>     }
>  }
>  
> +static void
> +discard_sub_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb,
> +                        GLsizei numAttachments, const GLenum *attachments,
> +                        GLint x, GLint y, GLsizei width, GLsizei height)
> +{
> +   GLint i;
> +
> +   if (!ctx->Driver.DiscardSubFramebuffer)
> +      return;
> +
> +   for (i = 0; i < numAttachments; i++) {
> +      struct gl_renderbuffer_attachment *att =
> +            get_fb_attachment(ctx, fb, attachments[i]);
> +
> +      if (!att)
> +         continue;
> +
> +      ctx->Driver.DiscardSubFramebuffer(ctx, fb, att, x, y, width, height);
> +   }
> +}
> +
>  void GLAPIENTRY
>  _mesa_InvalidateSubFramebuffer_no_error(GLenum target, GLsizei numAttachments,
>                                          const GLenum *attachments, GLint x,
>                                          GLint y, GLsizei width, GLsizei height)
>  {
> -   /* no-op */
> +   struct gl_framebuffer *fb;
> +   GET_CURRENT_CONTEXT(ctx);
> +
> +   fb = get_framebuffer_target(ctx, target);
> +   if (!fb)
> +      return;
> +
> +   discard_sub_framebuffer(ctx, fb, numAttachments, attachments,
> +                           x, y, width, height);
>  }
>  
>  
> @@ -4727,6 +4756,9 @@ _mesa_InvalidateSubFramebuffer(GLenum target, GLsizei numAttachments,
>     invalidate_framebuffer_storage(ctx, fb, numAttachments, attachments,
>                                    x, y, width, height,
>                                    "glInvalidateSubFramebuffer");
> +
> +   discard_sub_framebuffer(ctx, fb, numAttachments, attachments,
> +                           x, y, width, height);
>  }
>  
>  
>