[Mesa-dev] [PATCH 1/3] i965: Override swizzles for integer luminance formats.

[Ian Romanick]

FWIW, this patch is

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

On 02/06/2015 02:32 PM, Kenneth Graunke wrote:
> The hardware's integer luminance formats are completely unusable;
> currently we fall back to RGBA.  This means we need to override
> the texture swizzle to obtain the XXX1 values expected for luminance
> formats.
> 
> Fixes spec/EXT_texture_integer/texwrap formats bordercolor [swizzled]
> on Broadwell - 100% of border color tests now pass on Broadwell.
> 
> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
> Cc: Chris Forbes <chrisf at ijw.co.nz>
> Cc: mesa-stable at lists.freedesktop.org
> ---
>  src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
> index 6456a61..5f81402 100644
> --- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
> +++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
> @@ -199,6 +199,14 @@ brw_get_texture_swizzle(const struct gl_context *ctx,
>        swizzles[1] = SWIZZLE_ZERO;
>        swizzles[2] = SWIZZLE_ZERO;
>        break;
> +   case GL_LUMINANCE:
> +      if (t->_IsIntegerFormat) {
> +         swizzles[0] = SWIZZLE_X;
> +         swizzles[1] = SWIZZLE_X;
> +         swizzles[2] = SWIZZLE_X;
> +         swizzles[3] = SWIZZLE_ONE;
> +      }
> +      break;
>     case GL_RED:
>     case GL_RG:
>     case GL_RGB:
>