[Mesa-dev] [PATCH 2/2] intel/blorp: Take an explicit filter parameter in blorp_blit

Chad Versace chadversary at chromium.org
Thu Jun 28 01:08:44 UTC 2018


On Tue 26 Jun 2018, Jason Ekstrand wrote:
> This lets us move the glBlitFramebuffer nonsense into the GL driver and
> make the usage of BLORP mutch more explicit and obvious as to what it's
> doing.
> ---
>  src/intel/blorp/blorp.h               |  3 +-
>  src/intel/blorp/blorp_blit.c          | 44 ++-----------------
>  src/intel/vulkan/anv_blorp.c          | 34 +++++++++++----
>  src/mesa/drivers/dri/i965/brw_blorp.c | 63 ++++++++++++++++++++++++++-
>  4 files changed, 93 insertions(+), 51 deletions(-)

> @@ -2253,39 +2250,6 @@ blorp_blit(struct blorp_batch *batch,
>        wm_prog_key.x_scale = 2.0f;
>     wm_prog_key.y_scale = params.src.surf.samples / wm_prog_key.x_scale;
>  
> -   const bool bilinear_filter = filter == GL_LINEAR &&
> -                                params.src.surf.samples <= 1 &&
> -                                params.dst.surf.samples <= 1;
> -
> -   /* We are downsampling a non-integer color buffer, so blend.
> -    *
> -    * Regarding integer color buffers, the OpenGL ES 3.2 spec says:
> -    *
> -    *    "If the source formats are integer types or stencil values, a
> -    *    single sample's value is selected for each pixel."
> -    *
> -    * This implies we should not blend in that case.
> -    */
> -   const bool blend =
> -      (params.src.surf.usage & ISL_SURF_USAGE_DEPTH_BIT) == 0 &&
> -      (params.src.surf.usage & ISL_SURF_USAGE_STENCIL_BIT) == 0 &&
> -      !isl_format_has_int_channel(params.src.surf.format) &&
> -      params.src.surf.samples > 1 &&
> -      params.dst.surf.samples <= 1;
> -
> -   if (blend && !blit_scaled) {
> -      wm_prog_key.filter = BLORP_FILTER_AVERAGE;
> -   } else if (blend && blit_scaled) {
> -      wm_prog_key.filter = BLORP_FILTER_BILINEAR;
> -   } else if (bilinear_filter) {
> -      wm_prog_key.filter = BLORP_FILTER_BILINEAR;
> -   } else {
> -      if (params.src.surf.samples > 1)
> -         wm_prog_key.filter = BLORP_FILTER_SAMPLE_0;
> -      else
> -         wm_prog_key.filter = BLORP_FILTER_NEAREST;
> -   }
> -
>     params.wm_inputs.rect_grid.x1 =
>        minify(params.src.surf.logical_level0_px.width, src_level) *
>        wm_prog_key.x_scale - 1.0f;

Crazy GL silliness, be gone! You are not welcome here, in this clean,
pure, do-what-i-say-not-what-i-mean Vulkan driver! Be banished to GL
silly-land forever!

[snip]

The following two hunks, combined, are large improvements.  It's crazy
that blorp correctly applied average filtering for multisampled
non-integer color attachments here *despite* the hardcoded GL_NEAREST in
hunk #1.

> @@ -1181,7 +1182,7 @@ resolve_surface(struct blorp_batch *batch,
>                ISL_FORMAT_UNSUPPORTED, ISL_SWIZZLE_IDENTITY,
>                src_x, src_y, src_x + width, src_y + height,
>                dst_x, dst_y, dst_x + width, dst_y + height,
> -              0x2600 /* GL_NEAREST */, false, false);
> +              filter, false, false);
>  }
>  
>  static void
> @@ -1220,13 +1221,22 @@ resolve_image(struct anv_device *device,
>                                          dst_surf.aux_usage,
>                                          dst_level, dst_layer, 1);
>  
> +      enum blorp_filter filter;
> +      if ((src_surf.surf->usage & ISL_SURF_USAGE_DEPTH_BIT) ||
> +          (src_surf.surf->usage & ISL_SURF_USAGE_STENCIL_BIT) ||
> +          isl_format_has_int_channel(src_surf.surf->format)) {
> +         filter = BLORP_FILTER_SAMPLE_0;
> +      } else {
> +         filter = BLORP_FILTER_AVERAGE;
> +      }
> +
>        assert(!src_image->format->can_ycbcr);
>        assert(!dst_image->format->can_ycbcr);
>  
>        resolve_surface(batch,
>                        &src_surf, src_level, src_layer,
>                        &dst_surf, dst_level, dst_layer,
> -                      src_x, src_y, dst_x, dst_y, width, height);
> +                      src_x, src_y, dst_x, dst_y, width, height, filter);
>     }
>  }
>  
> @@ -1341,6 +1351,13 @@ anv_cmd_buffer_resolve_subpass(struct anv_cmd_buffer *cmd_buffer)
>           assert(src_iview->aspect_mask == VK_IMAGE_ASPECT_COLOR_BIT &&
>                  dst_iview->aspect_mask == VK_IMAGE_ASPECT_COLOR_BIT);
>  
> +         enum blorp_filter filter;
> +         if (isl_format_has_int_channel(src_iview->planes[0].isl.format)) {
> +            filter = BLORP_FILTER_SAMPLE_0;
> +         } else {
> +            filter = BLORP_FILTER_AVERAGE;
> +         }
> +
>           struct blorp_surf src_surf, dst_surf;
>           get_blorp_surf_for_anv_image(cmd_buffer->device, src_iview->image,
>                                        VK_IMAGE_ASPECT_COLOR_BIT,

[snip]

> @@ -324,6 +324,65 @@ brw_blorp_blit_miptrees(struct brw_context *brw,
>        src_format = dst_format = MESA_FORMAT_R_FLOAT32;
>     }
>  
> +   enum blorp_filter blorp_filter;
> +   if (fabs(dst_x1 - dst_x0) == fabs(src_x1 - src_x0) &&
> +       fabs(dst_y1 - dst_y0) == fabs(src_y1 - src_y0)) {

You should use fabsf() here because all params are floats.

> +      if (src_mt->surf.samples > 1 && dst_mt->surf.samples <= 1) {
> +         /* From the OpenGL ES 3.2 specification, section 16.2.1:
> +          *
> +          *    "If the read framebuffer is multisampled (its effective value
> +          *    of SAMPLE_BUFFERS is one) and the draw framebuffer is not (its
> +          *    value of SAMPLE_BUFFERS is zero), the samples corresponding to
> +          *    each pixel location in the source are converted to a single
> +          *    sample before being written to the destination.  The filter
> +          *    parameter is ignored. If the source formats are integer types
> +          *    or stencil values, a single sample’s value is selected for each
> +          *    pixel.  If the source formats are floating-point or normalized
> +          *    types, the sample values for each pixel are resolved in an
> +          *    implementation-dependent manner.  If the source formats are
> +          *    depth values, sample values are resolved in an implementation-
> +          *    dependent manner where the result will be between the minimum
> +          *    and maximum depth values in the pixel."
> +          *
> +          * For depth and stencil resolves, we choose to always use the value
> +          * at sample 0.
> +          */
> +         GLenum base_format = _mesa_get_format_base_format(src_mt->format);
> +         if (base_format == GL_DEPTH_COMPONENT ||
> +             base_format == GL_STENCIL_INDEX ||
> +             base_format == GL_DEPTH_STENCIL ||
> +             _mesa_is_format_integer(src_mt->format)) {
> +            /* The OpenGL ES 3.2 spec says:
> +             *
> +             *    "If the source formats are integer types or stencil values,
> +             *    a single sample's value is selected for each pixel."
> +             *
> +             * Just take sample 0 in this case.
> +             */
> +            blorp_filter = BLORP_FILTER_SAMPLE_0;
> +         } else {
> +            blorp_filter = BLORP_FILTER_AVERAGE;
> +         }
> +      } else {
> +         /* From the OpenGL 4.6 specification, section 18.3.1:
> +          *
> +          *    "If the source and destination dimensions are identical, no
> +          *    filtering is applied."
> +          *
> +          * Using BLORP_FILTER_NONE will also handle the upsample case by
> +          * replicating the one value in the source to all values in the
> +          * destination.
> +          */
> +         blorp_filter = BLORP_FILTER_NONE;
> +      }
> +   } else if (gl_filter == GL_LINEAR ||
> +              gl_filter == GL_SCALED_RESOLVE_FASTEST_EXT ||
> +              gl_filter == GL_SCALED_RESOLVE_NICEST_EXT) {
> +      blorp_filter = BLORP_FILTER_BILINEAR;
> +   } else {
> +      blorp_filter = BLORP_FILTER_NEAREST;
> +   }

This hunk is great. Blorp no longer needs to reverse-engineer what GL
was poorly trying to tell it.

With s/fabs/fabsf/, this patch is
Reviewed-by: Chad Versace <chadversary at chromium.org>


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