[Mesa-dev] TBOs: Mesa and i965 sampling support.

[Kenneth Graunke]

On 03/29/2012 06:29 PM, Ian Romanick wrote:
> On 03/28/2012 10:58 AM, Eric Anholt wrote:
>> This gets the texture buffer object support to the point of running
>> and passing the piglit core tests other than deprecated formats on
>> i965.
>>
>> Patch 2 is the glapi regen (I want the time back I've lost to
>> regen failure this week).
>>
>> Patch 13 we may want to extend to gen6 before landing.
>>
>> Patch 14 I'm not sure if we want to land at all -- it gets the
>> deprecated formats almost working, but we may want to just not do TBOs
>> pre-3.1, and drop all that ugly code.
>
> TBOs (and UBOs) have a bit of fail in their specification. The each
> require either GLSL 1.40 (by virtue of being in OpenGL 3.1) or
> GL_EXT_gpu_shader4.
>
> I think we decided to not bother with GLSL 1.40 pre-3.1.

Yeah, I think that's best.  I'm really not excited at the prospect of 
more luminance/alpha texture disaster.  That stuff should die in a fire.

> I'm not super excited about GL_EXT_gpu_shader4. Do we know of any
> applications that use that EXT and don't use either GLSL 1.30 or GLSL 1.40?
>
> If we're not going to expose any version (or extension) of GLSL that
> adds the required support on pre-3.1, I don't see any reason to support
> the deprecated formats.
>
>> I haven't actually turned on the extension, pending resolution on
>> patch 14. So far I'm testing with GL 3.1 override, GLSL 1.40
>> override, and +GL_ARB_tbo extension override.