[Mesa-dev] [PATCH] i965: Fix border color handling for deprecated SNORM formats.

[Ian Romanick]

On 12/20/2012 04:07 PM, Eric Anholt wrote:
> We don't have native hardware support for these, so they get promoted to
> RGBA, in which case we don't have hardware dealing with the channel
> swizzling for us.
>
> Fixes piglit EXT_texture_snorm/texwrap formats bordercolor (-swizzled).
> ---
>   src/mesa/drivers/dri/i965/brw_wm_sampler_state.c |   31 ++++++++++++++++++++--
>   1 file changed, 29 insertions(+), 2 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
> index 0d1f249..006aa68 100644
> --- a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
> +++ b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
> @@ -89,7 +89,8 @@ upload_default_color(struct brw_context *brw, struct gl_sampler_object *sampler,
>      struct gl_texture_image *firstImage = texObj->Image[0][texObj->BaseLevel];
>      float color[4];
>
> -   if (firstImage->_BaseFormat == GL_DEPTH_COMPONENT) {
> +   switch (firstImage->_BaseFormat) {
> +   case GL_DEPTH_COMPONENT:
>         /* GL specs that border color for depth textures is taken from the
>          * R channel, while the hardware uses A.  Spam R into all the
>          * channels for safety.
> @@ -98,11 +99,37 @@ upload_default_color(struct brw_context *brw, struct gl_sampler_object *sampler,
>         color[1] = sampler->BorderColor.f[0];
>         color[2] = sampler->BorderColor.f[0];
>         color[3] = sampler->BorderColor.f[0];
> -   } else {
> +      break;
> +   case GL_ALPHA:
> +      color[0] = 0.0;
> +      color[1] = 0.0;
> +      color[2] = 0.0;
> +      color[3] = sampler->BorderColor.f[3];
> +      break;
> +   case GL_INTENSITY:
> +      color[0] = sampler->BorderColor.f[0];
> +      color[1] = sampler->BorderColor.f[0];
> +      color[2] = sampler->BorderColor.f[0];
> +      color[3] = sampler->BorderColor.f[0];
> +      break;
> +   case GL_LUMINANCE:
> +      color[0] = sampler->BorderColor.f[0];
> +      color[1] = sampler->BorderColor.f[0];
> +      color[2] = sampler->BorderColor.f[0];
> +      color[3] = 1.0;
> +      break;
> +   case GL_LUMINANCE_ALPHA:
> +      color[0] = sampler->BorderColor.f[0];
> +      color[1] = sampler->BorderColor.f[0];
> +      color[2] = sampler->BorderColor.f[0];
> +      color[3] = sampler->BorderColor.f[3];
> +      break;
> +   default:
>         color[0] = sampler->BorderColor.f[0];
>         color[1] = sampler->BorderColor.f[1];
>         color[2] = sampler->BorderColor.f[2];
>         color[3] = sampler->BorderColor.f[3];

Is this the correct handing for RED / RG?  If it's not, it's a 
pre-existing issue.  I haven't reviewed that part of the spec recently...

> +      break;
>      }
>
>      /* In some cases we use an RGBA surface format for GL RGB textures,
>