[Mesa-dev] [PATCH] anv: don't skip the VUE header if we are reading gl_Layer in a fragment shader

[Jason Ekstrand]

Thanks!

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>

On Jan 5, 2017 05:10, "Iago Toral Quiroga" <itoral at igalia.com> wrote:

> This is the same we do in the GL driver: the hardware provides gl_Layer
> in the VUE header, so when the fragment shader reads it we can't skip it.
> ---
>
> With this patch we now successfully read gl_Layer in fragment shaders.
> Layered
> rendering still does not work though, probably because we still need to
> hook up
> the layer_id stuff that Jason added some time ago. I'll look into that
> next.
>
>  src/intel/vulkan/genX_pipeline.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/src/intel/vulkan/genX_pipeline.c b/src/intel/vulkan/genX_
> pipeline.c
> index 845d020..c1d8ae6 100644
> --- a/src/intel/vulkan/genX_pipeline.c
> +++ b/src/intel/vulkan/genX_pipeline.c
> @@ -291,6 +291,8 @@ emit_3dstate_sbe(struct anv_pipeline *pipeline)
>  #  define swiz sbe
>  #endif
>
> +   /* Skip the VUE header and position slots by default */
> +   unsigned urb_entry_read_offset = 1;
>     int max_source_attr = 0;
>     for (int attr = 0; attr < VARYING_SLOT_MAX; attr++) {
>        int input_index = wm_prog_data->urb_setup[attr];
> @@ -298,6 +300,12 @@ emit_3dstate_sbe(struct anv_pipeline *pipeline)
>        if (input_index < 0)
>           continue;
>
> +      /* gl_Layer is stored in the VUE header */
> +      if (attr == VARYING_SLOT_LAYER) {
> +         urb_entry_read_offset = 0;
> +         continue;
> +      }
> +
>        if (attr == VARYING_SLOT_PNTC) {
>           sbe.PointSpriteTextureCoordinateEnable = 1 << input_index;
>           continue;
> @@ -322,18 +330,22 @@ emit_3dstate_sbe(struct anv_pipeline *pipeline)
>           swiz.Attribute[input_index].ComponentOverrideZ = true;
>           swiz.Attribute[input_index].ComponentOverrideW = true;
>        } else {
> -         assert(slot >= 2);
> -         const int source_attr = slot - 2;
> -         max_source_attr = MAX2(max_source_attr, source_attr);
>           /* We have to subtract two slots to accout for the URB entry
> output
>            * read offset in the VS and GS stages.
>            */
> +         assert(slot >= 2);
> +         const int source_attr = slot - 2 * urb_entry_read_offset;
> +         max_source_attr = MAX2(max_source_attr, source_attr);
>           swiz.Attribute[input_index].SourceAttribute = source_attr;
>        }
>     }
>
> -   sbe.VertexURBEntryReadOffset = 1; /* Skip the VUE header and position
> slots */
> +   sbe.VertexURBEntryReadOffset = urb_entry_read_offset;
>     sbe.VertexURBEntryReadLength = DIV_ROUND_UP(max_source_attr + 1, 2);
> +#if GEN_GEN >= 8
> +   sbe.ForceVertexURBEntryReadOffset = true;
> +   sbe.ForceVertexURBEntryReadLength = true;
> +#endif
>
>     uint32_t *dw = anv_batch_emit_dwords(&pipeline->batch,
>                                          GENX(3DSTATE_SBE_length));
> --
> 2.7.4
>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/mesa-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20170106/b7aa5b51/attachment-0001.html>