[Mesa-dev] [PATCH 2/2] mesa: add _mesa_feature_removed() helper

[Ian Romanick]

On 07/27/2012 09:19 AM, nobled wrote:
> And a more trivial _mesa_feature_deprecated().

I don't think this patch is going to be useful.  There are only three 
pieces of functionality that are deprecated but not removed.

1. Line widths > 1.0.

2. The queries for MAX_VARYING_COMPONENTS and MAX_VARYING_FLOATS 
(deprecated in 3.2).

3. The queries for NUM_COMPRESSED_TEXTURE_FORMATS and
COMPRESSED_TEXTURE_FORMATS (deprecated in 4.2).

In all other cases simply knowing that ctx->API == API_OPENGL_CORE is 
enough information.  I have a bunch of patches (patch carpet bombing) 
that make ES 1.x and ES 2.0 filtering use similar mechanism.

Since there are so few special cases, I think it's okay to open-code the 
checks.

> ---
>   src/mesa/main/context.c |   29 +++++++++++++++++++++++++++++
>   src/mesa/main/context.h |   14 ++++++++++++++
>   2 files changed, 43 insertions(+)
>
> diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
> index 18a9ac8..1a025e8 100644
> --- a/src/mesa/main/context.c
> +++ b/src/mesa/main/context.c
> @@ -1897,5 +1897,34 @@ _mesa_valid_to_render(struct gl_context *ctx,
> const char *where)
>      return GL_TRUE;
>   }
>
> +GLboolean
> +_mesa_feature_removed(struct gl_context *ctx, int deprecated, int removed)
> +{
> +   int version = ctx->VersionMajor * 10 + ctx->VersionMinor;
> +
> +   /* Has not been deprecated or removed in this version. */
> +   if (version < deprecated)
> +      return GL_FALSE;
> +   /* Has been deprecated, and removed since this is a forward-compatible
> +      context. */
> +   if (ctx->Const.ContextFlags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)
> +      return GL_TRUE;
> +   /* Has not been removed from any core GL version yet. */
> +   if (removed == 0)
> +      return GL_FALSE;
> +   /* Has been deprecated, but not removed in this version, and this is
> +      not a forward-compatible context, so it's still present. */
> +   if (version < removed)
> +      return GL_FALSE;
> +   /* Has been removed in this version, but this is a compatibility
> +      context, which restores removed features. */
> +   if (ctx->Const.ProfileMask & GL_CONTEXT_COMPATIBILITY_PROFILE_BIT)
> +      return GL_FALSE;
> +
> +   /* Has been removed in this version, and this is a core context. */
> +   assert(ctx->Const.ProfileMask & GL_CONTEXT_CORE_PROFILE_BIT);
> +   return GL_TRUE;
> +}
> +
>
>   /*@}*/
> diff --git a/src/mesa/main/context.h b/src/mesa/main/context.h
> index a66dd50..169dde0 100644
> --- a/src/mesa/main/context.h
> +++ b/src/mesa/main/context.h
> @@ -165,6 +165,20 @@ extern GLboolean
>   _mesa_valid_to_render(struct gl_context *ctx, const char *where);
>
>
> +static inline GLboolean
> +_mesa_feature_deprecated(struct gl_context *ctx, int deprecated)
> +{
> +   int version = ctx->VersionMajor * 10 + ctx->VersionMinor;
> +
> +   /* Has been deprecated or removed in this version. */
> +   if (version >= deprecated)
> +      return GL_TRUE;
> +   return GL_FALSE;
> +}
> +
> +extern GLboolean
> +_mesa_feature_removed(struct gl_context *ctx, int deprecated, int removed);
> +
>
>   /** \name Miscellaneous */
>   /*@{*/
>