[Mesa-dev] [PATCH] anv: advertise 8 subpixel precision bits

[Jason Ekstrand]

Could we please also add a line which explicitly sets the precision in
3DSTATE_SF?  That way it's clearer from the code what's going on.

On Wed, Feb 20, 2019 at 11:19 AM Juan A. Suarez Romero <jasuarez at igalia.com>
wrote:

> On one side, when emitting 3DSTATE_SF, VertexSubPixelPrecisionSelect is
> used to select between 8 bit subpixel precision (value 0) or 4 bit
> subpixel precision (value 1). As this value is not set, means it is
> taking the value 0, so 8 bit are used.
>
> On the other side, in the Vulkan CTS tests, if the reference rasterizer,
> which uses 8 bit precision, as it is used to check what should be the
> expected value for the tests, is changed to use 4 bit as ANV was
> advertising so far, some of the tests will fail.
>
> So it seems ANV is actually using 8 bits.
>
> CC: Jason Ekstrand <jason at jlekstrand.net>
> CC: Kenneth Graunke <kenneth at whitecape.org>
> ---
>  src/intel/vulkan/anv_device.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/intel/vulkan/anv_device.c b/src/intel/vulkan/anv_device.c
> index 3120865466a..95224407318 100644
> --- a/src/intel/vulkan/anv_device.c
> +++ b/src/intel/vulkan/anv_device.c
> @@ -1095,7 +1095,7 @@ void anv_GetPhysicalDeviceProperties(
>           16 * devinfo->max_cs_threads,
>           16 * devinfo->max_cs_threads,
>        },
> -      .subPixelPrecisionBits                    = 4 /* FIXME */,
> +      .subPixelPrecisionBits                    = 8,
>        .subTexelPrecisionBits                    = 4 /* FIXME */,
>        .mipmapPrecisionBits                      = 4 /* FIXME */,
>        .maxDrawIndexedIndexValue                 = UINT32_MAX,
> --
> 2.20.1
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20190220/4000cfe2/attachment-0001.html>