[Mesa-stable] [PATCH V3 09/10] mesa: Add support to unpack depth-stencil texture in to FLOAT_32_UNSIGNED_INT_24_8_REV

[Brian Paul]

On 03/25/2014 06:01 PM, Anuj Phogat wrote:
> V2: Follow the new naming convention for unpack functions.
>      Use double precision for converting Z24 to a float.
>
> V3: Unpack stencil value to most significant byte.
>      Use 'struct z32f_x24s8' type.
>
> Cc: <mesa-stable at lists.freedesktop.org>
> Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
> ---
>   src/mesa/main/format_unpack.c | 80 ++++++++++++++++++++++++++++++++++++++++++-
>   src/mesa/main/format_unpack.h |  5 +++
>   2 files changed, 84 insertions(+), 1 deletion(-)
>
> diff --git a/src/mesa/main/format_unpack.c b/src/mesa/main/format_unpack.c
> index 7abbe46..6e6bed8 100644
> --- a/src/mesa/main/format_unpack.c
> +++ b/src/mesa/main/format_unpack.c
> @@ -4264,6 +4264,80 @@ _mesa_unpack_uint_24_8_depth_stencil_row(mesa_format format, GLuint n,
>      }
>   }
>
> +static void
> +unpack_float_32_uint_24_8_Z24_UNORM_S8_UINT(const GLuint *src,
> +                                            GLuint *dst, GLuint n)
> +{
> +   GLuint i;
> +   struct z32f_x24s8 *d = (struct z32f_x24s8 *) dst;
> +   const GLdouble scale = 1.0 / (GLdouble) 0xffffff;
> +
> +   for (i = 0; i < n; i++) {
> +      const GLuint z24 = src[i] & 0xffffff;
> +      d[i].z = z24 * scale;
> +      d[i].x24s8 = src[i] & 0xff000000;
> +      assert(d[i].z >= 0.0f);
> +      assert(d[i].z <= 1.0f);
> +   }
> +}
> +
> +static void
> +unpack_float_32_uint_24_8_Z32_FLOAT_S8X24_UINT(const GLuint *src,
> +                                               GLuint *dst, GLuint n)
> +{
> +   GLuint i;
> +   const struct z32f_x24s8 *s = (const struct z32f_x24s8 *) src;
> +   struct z32f_x24s8 *d = (struct z32f_x24s8 *) dst;
> +
> +   for (i = 0; i < n; i++) {
> +      d[i].z = s[i].z;
> +      d[i].x24s8 = (s[i].x24s8 & 0xff) << 24;
> +   }
> +}
> +
> +static void
> +unpack_float_32_uint_24_8_S8_UINT_Z24_UNORM(const GLuint *src,
> +                                            GLuint *dst, GLuint n)
> +{
> +   GLuint i;
> +   struct z32f_x24s8 *d = (struct z32f_x24s8 *) dst;
> +   const GLdouble scale = 1.0 / (GLdouble) 0xffffff;
> +
> +   for (i = 0; i < n; i++) {
> +      const GLuint z24 = src[i] >> 8;
> +      d[i].z = z24 * scale;
> +      d[i].x24s8 = (src[i] & 0xff) << 24;
> +      assert(d[i].z >= 0.0f);
> +      assert(d[i].z <= 1.0f);
> +   }
> +}
> +
> +/**
> + * Unpack depth/stencil returning as GL_FLOAT_32_UNSIGNED_INT_24_8_REV.
> + * \param format  the source data format
> + */
> +void
> +_mesa_unpack_float_32_uint_24_8_depth_stencil_row(mesa_format format, GLuint n,
> +			                          const void *src, GLuint *dst)
> +{
> +   switch (format) {
> +   case MESA_FORMAT_S8_UINT_Z24_UNORM:
> +      unpack_float_32_uint_24_8_S8_UINT_Z24_UNORM(src, dst, n);
> +      break;
> +   case MESA_FORMAT_Z24_UNORM_S8_UINT:
> +      unpack_float_32_uint_24_8_Z24_UNORM_S8_UINT(src, dst, n);
> +      break;
> +   case MESA_FORMAT_Z32_FLOAT_S8X24_UINT:
> +      unpack_float_32_uint_24_8_Z32_FLOAT_S8X24_UINT(src, dst, n);
> +      break;
> +   default:
> +      _mesa_problem(NULL,
> +                    "bad format %s in _mesa_unpack_uint_24_8_depth_stencil_row",
> +                    _mesa_get_format_name(format));
> +      return;
> +   }
> +}
> +
>   /**
>    * Unpack depth/stencil
>    * \param format  the source data format
> @@ -4274,12 +4348,16 @@ _mesa_unpack_depth_stencil_row(mesa_format format, GLuint n,
>   	                       const void *src, GLenum type,
>                                  GLuint *dst)
>   {
> -   assert(type == GL_UNSIGNED_INT_24_8);
> +   assert(type == GL_UNSIGNED_INT_24_8 ||
> +          type == GL_FLOAT_32_UNSIGNED_INT_24_8_REV);
>
>      switch (type) {
>      case GL_UNSIGNED_INT_24_8:
>         _mesa_unpack_uint_24_8_depth_stencil_row(format, n, src, dst);
>         break;
> +   case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
> +      _mesa_unpack_float_32_uint_24_8_depth_stencil_row(format, n, src, dst);
> +      break;
>      default:
>         _mesa_problem(NULL,
>                       "bad type 0x%x in _mesa_unpack_depth_stencil_row",
> diff --git a/src/mesa/main/format_unpack.h b/src/mesa/main/format_unpack.h
> index 5904a28..51f97df 100644
> --- a/src/mesa/main/format_unpack.h
> +++ b/src/mesa/main/format_unpack.h
> @@ -64,6 +64,11 @@ _mesa_unpack_uint_24_8_depth_stencil_row(mesa_format format, GLuint n,
>   					 const void *src, GLuint *dst);
>
>   void
> +_mesa_unpack_float_32_uint_24_8_depth_stencil_row(mesa_format format,
> +                                                  GLuint n,
> +                                                  const void *src,
> +                                                  GLuint *dst);
> +void
>   _mesa_unpack_depth_stencil_row(mesa_format format, GLuint n,
>                                 const void *src, GLenum type,
>                                 GLuint *dst);
>

One last question.  My reading of GL_NV_depth_buffer_float is that the 
stencil byte goes in the least significant position of the uint, not the 
most significant position.  Is MSB the Intel/gen convention?

Maybe we should have a comment on 
_mesa_unpack_float_32_uint_24_8_depth_stencil_row() just to make it 
clear where the stencil byte winds up.

Thanks.

-Brian