[Mesa-dev] [PATCH 2/2] softpipe: fix depth sampling for linear vs nearest.

[Dave Airlie]

On Sun, Dec 18, 2011 at 9:27 PM, Dave Airlie <airlied at gmail.com> wrote:
> From: Dave Airlie <airlied at redhat.com>
>
> This sample compare was always doing linear, and this makes the
> glsl-fs-shadow1DArray test render like the Intel driver.
>
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>  src/gallium/drivers/softpipe/sp_tex_sample.c |   23 ++++++++++++++++-------
>  1 files changed, 16 insertions(+), 7 deletions(-)
>
> diff --git a/src/gallium/drivers/softpipe/sp_tex_sample.c b/src/gallium/drivers/softpipe/sp_tex_sample.c
> index 72629a0..40ad786 100644
> --- a/src/gallium/drivers/softpipe/sp_tex_sample.c
> +++ b/src/gallium/drivers/softpipe/sp_tex_sample.c
> @@ -2172,13 +2172,22 @@ sample_compare(struct tgsi_sampler *tgsi_sampler,
>       break;
>    }
>
> -   /* convert four pass/fail values to an intensity in [0,1] */
> -   val = 0.25F * (k0 + k1 + k2 + k3);
> -
> -   /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
> -   for (j = 0; j < 4; j++) {
> -      rgba[0][j] = rgba[1][j] = rgba[2][j] = val;
> -      rgba[3][j] = 1.0F;
> +   if (sampler->mag_img_filter == PIPE_TEX_FILTER_LINEAR) {
> +      /* convert four pass/fail values to an intensity in [0,1] */
> +      val = 0.25F * (k0 + k1 + k2 + k3);
> +
> +      /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
> +      for (j = 0; j < 4; j++) {
> +        rgba[0][j] = rgba[1][j] = rgba[2][j] = val;
> +        rgba[3][j] = 1.0F;
> +      }
> +   } else {
> +      for (j = 0; j < 4; j++) {
> +        rgba[0][j] = k0;
> +        rgba[1][j] = k1;
> +        rgba[2][j] = k2;
> +        rgba[3][0] = 1.0F;

^ assume 0 should be j here, though it would be good if someone could
check my thinking, I mostly ported from swrast.

Dave.