[Mesa-dev] softpipe GL3 status
idr at freedesktop.org
Fri Jan 6 11:26:05 PST 2012
On 01/06/2012 09:04 AM, Dave Airlie wrote:
> Hi guys,
> Just a quick note, I've just spent a week or so trying to see where
> gallium and softpipe were w.r.t GL3.0 support.
> I've pushed a branch to my repo called softpipe-gl3. It contains
> patches in various state of usefulness but it brings the piglit
> results to 220 failures in 7623 tests, which isn't bad.
> Outstanding known problems (stuff I've dug into).
> smooth interpolation is broken in softpipe, worth about 70-100 fixes
> at a quick guess.
> integer abs - we have no TGSI representation for this, should we lower
> it to something?
Or just generate some TGSI instructions to implement it. You should be
able to fake it with a CMP-like instruction. I think that's how i915
does it in hardware.
> integer SSG (set sign) - no TGSI for this, lower it?
Where is SSG being generated? I thought ir_to_mesa was the only thing
that generated it, and Gallium shouldn't hit that path.
> roundEven - need to implement softpipe round to match hw rounds which
> are roundEven.
> cube shadow sampling, some reason ends up getting info from the fallback texture
Something in Gallium is probably deciding that GL_DEPTH_COMPONENT is
invalid for a cubemap and marking it as incomplete.
> fbo-stencil tests, st/mesa needs to implement st_BlitFramebuffer(GL_STENCIL).
> minmax: need to increase texture array levels to 256 and missing
> multisample support.
> the unknown stuff includes some GLSL compiler failures and generic GLX issues.
Those are core Mesa problems. I wouldn't stress about those.
> Oh and this is all only available when DRAW_USE_LLVM=false is set,
> adding integer support to LLVM is a bit of a bigger task, and I'm not
> sure I can really get into it at the moment.
> in case anyone is looking for any motivation on why I've been working
> on this, it just seemed like it would be nice to have a reference sw
> GL3.0 compatible renderer in Mesa 8.0.
I agree! However, the VMware guys *really* want us to make the 8.0
branch today to align with another distro's schedule. I'm not sure if
fixes for the issues above are acceptable post-branch or not. You
should talk with Brian and Jakob.
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