[Mesa-dev] [PATCH 0/5] MSAA on R6xx

[Török Edwin]

On 08/27/2012 05:09 PM, Marek Olšák wrote:
> I think the forward compatible contexts can only be created with
> OpenGL 3.1 and later versions, but I am not 100% sure.

According to comments in GLFW it appears that forward compat. contexts should work with 3.0:
// Context profiles are only defined for OpenGL version 3.2 and above
// Forward-compatible contexts are only defined for OpenGL version 3.0 and above

Searching the OpenGL 3.0 spec I found this: "it is possible to create an OpenGL 3.0 context which does not support dep-
recated features. Such a context is called a forward compatible context, while a
context supporting all OpenGL 3.0 features is called a full context."

"If CONTEXT FLAG FORWARD COMPATIBLE BIT is set in
CONTEXT FLAGS, then the context is a forward-compatible context as defined in
appendix E, and the deprecated features described in that appendix are not sup-
ported; otherwise the context is a full context, and all features described in the
specification are supported."

I don't know how useful a forward compat 3.0 context would be in practice though, its neither core profile,
neither a full context, and most examples I've seen use 3.2 or 3.3 with core + forward.

>From what I've seen Mesa would map forward compat to core internally.

Best regards,
--Edwin

> 
> Marek
> 
> On Mon, Aug 27, 2012 at 3:47 PM, Török Edwin
> <edwin+ml-mesadev at etorok.net> wrote:
>> On 08/27/2012 12:33 PM, Török Edwin wrote:
>>> On 08/27/2012 05:00 AM, Marek Olšák wrote:
>>>> This series implements MSAA for the R6xx family of GPUs.
>>>>
>>>> The only problem is that the depth decompression doesn't work with MSAA depth buffers, which means for the GL user that depth-stencil blitting and depth-stencil resolve don't work, although those features are used very rarely, if at all.
>>>>
>>>> Also, the R11G11B10 float format isn't resolved correctly (it's too dark), but at least we have the option not to expose it.
>>>>
>>>> Please review.
>>>>
>>>> This is the last series I'd like to have in the next Mesa release and then we'll have OpenGL 3.0 on all chipsets except for Cayman (R9xx). Cayman will probably take more time, because it doesn't have transform feedback either.
>>>
>>> Nice, I get 3.0 on my RV730 [*]:
>>> OpenGL renderer string: Gallium 0.4 on AMD RV730
>>> OpenGL version string: 3.0 Mesa 8.1-devel (git-59723c7)
>>> OpenGL shading language version string: 1.30
>>>
>>> Is the creation of core/forward-compat contexts supposed to work, or do I need to build libglx/libdri2 from git for that to work?
>>> I see GLX_ARB_create_context and GLX_ARB_create_context_profile advertised in the client GLX extensions but not in the server extensions.
>>>
>>> X.Org X Server 1.12.3.902 (1.12.4 RC 2)
>>> Release Date: 2012-08-19
>>>
>>
>> I just built X.Org X Server 1.12.99.905 (1.13.0 RC 5) from git and now I see the GLX_ARB_create_context and GLX_ARB_create_context_profile server extensions.
>> Requesting a forward compatible context however gives (with glutInitContext*):
>> X Error of failed request:  GLXBadFBConfig
>>   Major opcode of failed request:  153 (GLX)
>>   Minor opcode of failed request:  34 ()
>>   Serial number of failed request:  34
>>   Current serial number in output stream:  33
>>
>> --Edwin
>>
>> _______________________________________________
>> mesa-dev mailing list
>> mesa-dev at lists.freedesktop.org
>> http://lists.freedesktop.org/mailman/listinfo/mesa-dev
>