[Mesa-dev] ARB_copy_image support in Gallium

[Ilia Mirkin]

As I'm guessing that it's unlikely that the VMWare implementation will
get upstreamed before the Mesa 11.0 branch point, how do people feel
about including the below implementation *without* the extension
enable? That way people will still be able to run bioshock infinite
without resorting to patching (by adding the ext override) while we
wait for a proper implementation.

Thoughts?

  -ilia


On Mon, Jul 20, 2015 at 3:19 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> On Mon, Jul 20, 2015 at 2:44 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>> Hi Brian,
>>
>> You marked off ARB_copy_image (and ARB_clear_texture) as in-progress
>> by VMware some months ago -- has there been any movement on that? It
>> appears that Bioshock Infinite requires ARB_copy_image so might be
>> nice to get that added in.
>>
>> The complication in implementing ARB_copy_image was that st/mesa will
>> pick potentially different PIPE_FORMAT enums for the same internal
>> format, depending on the parameters to the glTexImage call. A
>> developer (irc handle Leftmost, I forget his real name, sorry) tried
>> to wrestle with the issues this presents, but as I recall ended up
>> coming up short.
>>
>> The final implementation probably needs some combination of
>> resource_copy_region and blit. I think resource_copy_region currently
>> is spec'd to require identical formats in src and dst, but that could
>> be relaxed.
>>
>> Anyways, would be interested in hearing whether you guys have made any
>> progress, or if you had thoughts on proper implementation.
>>
>> Cheers,
>>
>>   -ilia
>
> As an aside, here's a very naive implementation of the ext, which
> fails for lots of reasons not the least of which is that we default to
> BGRA instead of RGBA. Perhaps we could create a resource_copy_region
> version that also takes (or knows about) swizzles... that should also
> cover many (all?) of the situations I think.
>
>   -ilia
>
> diff --git a/src/mesa/state_tracker/st_cb_texture.c
> b/src/mesa/state_tracker/st_cb_texture.c
> index 7ea3846..b6b0081 100644
> --- a/src/mesa/state_tracker/st_cb_texture.c
> +++ b/src/mesa/state_tracker/st_cb_texture.c
> @@ -1864,6 +1864,28 @@ st_TextureView(struct gl_context *ctx,
>     return GL_TRUE;
>  }
>
> +static void
> +st_CopyImageSubData(struct gl_context *ctx,
> +                    struct gl_texture_image *src_image,
> +                    int src_x, int src_y, int src_z,
> +                    struct gl_texture_image *dst_image,
> +                    int dst_x, int dst_y, int dst_z,
> +                    int src_width, int src_height)
> +{
> +   struct st_context *st = st_context(ctx);
> +   struct pipe_context *pipe = st->pipe;
> +   struct st_texture_image *src = st_texture_image(src_image);
> +   struct st_texture_image *dst = st_texture_image(dst_image);
> +
> +   struct pipe_box box;
> +
> +   u_box_2d_zslice(src_x, src_y, src_z, src_width, src_height, &box);
> +   pipe->resource_copy_region(pipe, dst->pt, dst_image->Level,
> +                              dst_x, dst_y, dst_z,
> +                              src->pt, src_image->Level,
> +                              &box);
> +}
> +
>
>  void
>  st_init_texture_functions(struct dd_function_table *functions)
> @@ -1896,4 +1918,6 @@ st_init_texture_functions(struct
> dd_function_table *functions)
>
>     functions->AllocTextureStorage = st_AllocTextureStorage;
>     functions->TextureView = st_TextureView;
> +
> +   functions->CopyImageSubData = st_CopyImageSubData;
>  }
> diff --git a/src/mesa/state_tracker/st_extensions.c
> b/src/mesa/state_tracker/st_extensions.c
> index b1057f3..9bff7b4 100644
> --- a/src/mesa/state_tracker/st_extensions.c
> +++ b/src/mesa/state_tracker/st_extensions.c
> @@ -589,6 +589,7 @@ void st_init_extensions(struct pipe_screen *screen,
>      * Extensions that are supported by all Gallium drivers:
>      */
>     extensions->ARB_ES2_compatibility = GL_TRUE;
> +   extensions->ARB_copy_image = GL_TRUE;
>     extensions->ARB_draw_elements_base_vertex = GL_TRUE;
>     extensions->ARB_explicit_attrib_location = GL_TRUE;
>     extensions->ARB_explicit_uniform_location = GL_TRUE;