[Mesa-dev] [PATCH] mesa/teximage: add more targets for CompressedTexImage3D

[Nanley Chery]

On Wed, Nov 08, 2017 at 04:52:02PM +0100, Juan A. Suarez Romero wrote:
> From section 8.7, page 179 of OpenGL ES 3.2 spec:
> 
>   An INVALID_OPERATION error is generated by CompressedTexImage3D
>   if internalformat is one of the the formats in table 8.17 and target
>   is not TEXTURE_2D_ARRAY, TEXTURE_CUBE_MAP_ARRAY or TEXTURE_3D.
> 
> So far it was only considering TEXTURE_2D_ARRAY as valid target. Now it
> must consider also TEXTURE_CUBE_MAP_ARRAY and TEXTURE_3D.
> 

Not necessarily. The next sentence after the one you quoted states:

   An INVALID_OPERATION error is generated by CompressedTexImage3D if
   internalformat is TEXTURE_CUBE_MAP_ARRAY and the “Cube Map Array”
   column of table 8.17 is not checked, or if internalformat is
   TEXTURE_3D and the “3D Tex.” column of table 8.17 is not checked.

It seems that the OpenGL ES 3.2 spec has moved towards using a table to
determine valid compressed targets. It hasn't necessarily stated that
TEXTURE_CUBE_MAP_ARRAY and TEXTURE_3D are now valid. Though, by looking
at the table, I think we can conclude that TEXTURE_CUBE_MAP_ARRAY is now
valid.

> This fixes KHR-GLES32.core.texture_cube_map_array.etc2_texture
> ---
>  src/mesa/main/teximage.c | 17 ++++++-----------
>  1 file changed, 6 insertions(+), 11 deletions(-)
> 
> diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
> index 4ec6148bf42..2799669d28a 100644
> --- a/src/mesa/main/teximage.c
> +++ b/src/mesa/main/teximage.c
> @@ -1403,26 +1403,21 @@ _mesa_target_can_be_compressed(const struct gl_context *ctx, GLenum target,
>         * have already been handled by normal ETC2/EAC behavior.
>         */
>  
> -      /* From section 3.8.6, page 146 of OpenGL ES 3.0 spec:
> +      /* From section 8.7, page 179 of OpenGL ES 3.2 spec:
>         *
> -       *    "The ETC2/EAC texture compression algorithm supports only
> -       *     two-dimensional images. If internalformat is an ETC2/EAC format,
> -       *     glCompressedTexImage3D will generate an INVALID_OPERATION error if
> -       *     target is not TEXTURE_2D_ARRAY."
> +       *    "An INVALID_OPERATION error is generated by CompressedTexImage3D
> +       *     if internalformat is one of the the formats in table 8.17 and target is
> +       *     not TEXTURE_2D_ARRAY, TEXTURE_CUBE_MAP_ARRAY or TEXTURE_3D."
>         *
> -       * This should also be applicable for glTexStorage3D(). Other available
> -       * targets for these functions are: TEXTURE_3D and TEXTURE_CUBE_MAP_ARRAY.
> +       * This should also be applicable for glTexStorage3D().
>         */
> -      if (layout == MESA_FORMAT_LAYOUT_ETC2 && _mesa_is_gles3(ctx))
> -            return write_error(error, GL_INVALID_OPERATION);

The OpenGL ES 3.2 spec seems to be adding support for compressed
CUBE_MAP_ARRAYs, and not clarifying what the behavior should have been
in OpenGL ES 3.0. In this case, I think we should have a additional
condition and not replace the existing one.

>        target_can_be_compresed = _mesa_has_texture_cube_map_array(ctx);
>        break;
>     case GL_TEXTURE_3D:
>        switch (layout) {
>        case MESA_FORMAT_LAYOUT_ETC2:
>           /* See ETC2/EAC comment in case GL_TEXTURE_CUBE_MAP_ARRAY. */
> -         if (_mesa_is_gles3(ctx))
> -            return write_error(error, GL_INVALID_OPERATION);
> +         target_can_be_compresed = GL_TRUE;

None of the formats listed in table 8.17 have their 3D Tex. entry
checked.

-Nanley

>           break;
>        case MESA_FORMAT_LAYOUT_BPTC:
>           target_can_be_compresed = ctx->Extensions.ARB_texture_compression_bptc;
> -- 
> 2.13.6
>