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

[Ian Romanick]

On 07/27/2012 10:11 AM, Ian Romanick wrote:
> 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)

Also... there are a *ton* of places where this check is necessary.  I'd 
much rather have a simple pointer deference and compare than have a 
function call to all of this.

>> +{
>> +   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 */
>>   /*@{*/
>>
>