[Mesa-dev] [PATCH 01/18] mesa: Store the target index in gl_texture_object

[Brian Paul]

On 01/23/2014 03:12 PM, Fredrik Höglund wrote:
> On Wednesday 22 January 2014, Brian Paul wrote:
>> On 01/21/2014 03:35 PM, Fredrik Höglund wrote:
>>> This will be used by glBindTextures() so we don't have to look it up
>>> for each texture.
>>> ---
>>>    src/mesa/main/mtypes.h |    1 +
>>>    src/mesa/main/texobj.c |    2 ++
>>>    2 files changed, 3 insertions(+)
>>>
>>> diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
>>> index c396609..2fe47c4 100644
>>> --- a/src/mesa/main/mtypes.h
>>> +++ b/src/mesa/main/mtypes.h
>>> @@ -1194,6 +1194,7 @@ struct gl_texture_object
>>>       GLuint Name;                /**< the user-visible texture object ID */
>>>       GLchar *Label;               /**< GL_KHR_debug */
>>>       GLenum Target;              /**< GL_TEXTURE_1D, GL_TEXTURE_2D, etc. */
>>> +   GLuint TargetIndex;         /**< The gl_texture_unit::CurrentTex index */
>>
>> Could this be "gl_texture_index TargetIndex;"?
>
> It can indeed.  I'll change it.
>
>>>
>>>       struct gl_sampler_object Sampler;
>>>
>>> diff --git a/src/mesa/main/texobj.c b/src/mesa/main/texobj.c
>>> index 3c64c437..4d97275 100644
>>> --- a/src/mesa/main/texobj.c
>>> +++ b/src/mesa/main/texobj.c
>>> @@ -259,6 +259,7 @@ _mesa_copy_texture_object( struct gl_texture_object *dest,
>>>                               const struct gl_texture_object *src )
>>>    {
>>>       dest->Target = src->Target;
>>> +   dest->TargetIndex = src->TargetIndex;
>>>       dest->Name = src->Name;
>>>       dest->Priority = src->Priority;
>>>       dest->Sampler.BorderColor.f[0] = src->Sampler.BorderColor.f[0];
>>> @@ -1318,6 +1319,7 @@ _mesa_BindTexture( GLenum target, GLuint texName )
>>>             _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
>>>          }
>>>          newTexObj->Target = target;
>>> +      newTexObj->TargetIndex = targetIndex;
>>>       }
>>>
>>>       assert(valid_texture_object(newTexObj));
>>>
>>
>>
>> So the memset() in _mesa_initialize_texture_object() would implicitly
>> set TargetIndex = TEXTURE_2D_MULTISAMPLE_INDEX (zero).  Is that going to
>> cause any trouble?
>
> That's a good question.  TargetIndex is only used in _mesa_BindTextures()
> and unbind_texobj_from_texunits().  _mesa_BindTextures() checks if Target
> is valid before it uses TargetIndex.  If unbind_texobj_from_texunits()
> is called with a texture that has never been used, it doesn't matter that the
> index is zero, because the texture won't be bound to any unit anyway.
> It should probably exit early if the texture doesn't have a target though.
>
> So to the best of my knowledge it shouldn't be a problem.  But maybe it
> should be documented somewhere that TargetIndex is only valid when
> Target is valid.

Yeah, probably.  Sounds good otherwise.

-Brian