[Mesa-dev] [PATCH] mesa: add GL_OES_texture_stencil8 support

[Eduardo Lima Mitev]

On 02/16/2016 06:05 AM, Ilia Mirkin wrote:
> It's basically the same thing as GL_ARB_texture_stencil8 except that
> glCopyTexImage isn't supported, so add STENCIL_INDEX to the list of
> invalid GLES formats for glCopyTexImage.
> 
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
> 
> Seems to pass the few dEQP tests that are there. The ext is nearly identical to the desktop version.
> 
>  docs/GL3.txt                     | 2 +-
>  src/mesa/main/extensions_table.h | 1 +
>  src/mesa/main/teximage.c         | 2 ++
>  3 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/docs/GL3.txt b/docs/GL3.txt
> index 3c4db06..26847b9 100644
> --- a/docs/GL3.txt
> +++ b/docs/GL3.txt
> @@ -256,7 +256,7 @@ GLES3.2, GLSL ES 3.2
>    GL_OES_texture_border_clamp                          DONE (all drivers)
>    GL_OES_texture_buffer                                not started (based on GL_ARB_texture_buffer_object, GL_ARB_texture_buffer_range, and GL_ARB_texture_buffer_object_rgb32 that are all done)
>    GL_OES_texture_cube_map_array                        not started (based on GL_ARB_texture_cube_map_array, which is done for all drivers)
> -  GL_OES_texture_stencil8                              not started (based on GL_ARB_texture_stencil8, which is done for some drivers)
> +  GL_OES_texture_stencil8                              DONE (all drivers that support GL_ARB_texture_stencil8)
>    GL_OES_texture_storage_multisample_2d_array          DONE (all drivers that support GL_ARB_texture_multisample)
>  
>  More info about these features and the work involved can be found at
> diff --git a/src/mesa/main/extensions_table.h b/src/mesa/main/extensions_table.h
> index 43dc358..bcd12a2 100644
> --- a/src/mesa/main/extensions_table.h
> +++ b/src/mesa/main/extensions_table.h
> @@ -343,6 +343,7 @@ EXT(OES_texture_half_float                  , OES_texture_half_float
>  EXT(OES_texture_half_float_linear           , OES_texture_half_float_linear          ,  x ,  x ,  x , ES2, 2005)
>  EXT(OES_texture_mirrored_repeat             , dummy_true                             ,  x ,  x , ES1,  x , 2005)
>  EXT(OES_texture_npot                        , ARB_texture_non_power_of_two           ,  x ,  x , ES1, ES2, 2005)
> +EXT(OES_texture_stencil8                    , ARB_texture_stencil8                   ,  x ,  x ,  x ,  30, 2014)
>  EXT(OES_texture_storage_multisample_2d_array, ARB_texture_multisample                ,  x ,  x , ES1,  31, 2014)
>  EXT(OES_texture_view                        , ARB_texture_view                       ,  x ,  x ,  x ,  31, 2014)
>  EXT(OES_vertex_array_object                 , dummy_true                             ,  x ,  x , ES1, ES2, 2010)
> diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
> index 57765d7..8a4c628 100644
> --- a/src/mesa/main/teximage.c
> +++ b/src/mesa/main/teximage.c
> @@ -2285,8 +2285,10 @@ copytexture_error_check( struct gl_context *ctx, GLuint dimensions,
>        }
>        if (baseFormat == GL_DEPTH_COMPONENT ||
>            baseFormat == GL_DEPTH_STENCIL ||
> +          baseFormat == GL_STENCIL_INDEX ||
>            rb_base_format == GL_DEPTH_COMPONENT ||
>            rb_base_format == GL_DEPTH_STENCIL ||
> +          rb_base_format == GL_STENCIL_INDEX ||
>            ((baseFormat == GL_LUMINANCE_ALPHA ||
>              baseFormat == GL_ALPHA) &&
>             rb_base_format != GL_RGBA) ||
> 

Handling GL_STENCIL_INDEX8 should also be added to at least two
functions in glformats.c:

Based on these two constrains from the extension spec:

    "An INVALID_OPERATION error is generated by TexImage3D, TexImage2D,
    TexSubImage3D or TexSubImage2D, if <format> is STENCIL_INDEX and
    <type> is not <UNSIGNED_BYTE>"

and

    "An INVALID_OPERATION error is generated by TexImage3D and
     TexImage2D, if <format> is <STENCIL_INDEX> and internal format is
     not <STENCIL_INDEX8>"

The corresponding case for STENCIL_INDEX should be added to:

* _mesa_es3_effective_internal_format_for_format_and_type(), which
should return STENCIL_INDEX8 out of STENCIL_INDEX + UNSIGNED_BYTE.

* _mesa_es3_error_check_format_and_type(), which should fail any
combination other than STENCIL_INDEX8 + UNSIGNED_BYTE + STENCIL_INDEX.


These are the two cases off the top of my head, but there can be other
function that miss handling of STENCIL_INDEX8. Ideally, tests should
catch those though.

Eduardo