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

[Ian Romanick]

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.

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.