Intel Is Getting Very Close With Its Last Extension For OpenGL 4.3

[pal666]

every desktop driver will have 4.5 in september release, maybe not for every capable chip

[Gusar]

Yeah...both Baytrail and Haswell gained native support for 3-element vertex formats, while Ivybridge (as the older Gen7) doesn't support them and has to fall back to 4-element vertex formats. I'm not yet sure if that's essential, but that's why it is how it is.

Ah, so Baytrail has a few bonuses compared to Ivy.

Yes, definitely. It's required for ES 3.1, and we plan to support that on Gen7. Thanks for reminding me about those old patches!

Sadly, not always. The point of ARB_query_buffer_object is to be able to produce query results without stalling and synchronizing with the CPU. On Haswell, the GPU gained a new "command streamer math" feature which allows us to do simple arithmetic on counters in a pipelined fashion (read a starting/ending counter snapshot, subtract the two, multiply by 4, and so on). This lets us easily do everything we need on the GPU. Ivybridge and Baytrail don't have that. We /could/ do it by using a compute shader, or a vertex shader rendering a single point with transform feedback, but that requires re-programming the entire pipeline, which seems pretty complex and heavyweight. I suppose we could also just stall and use the CPU, but that seems rather unfortunate as well. So for now, it's Haswell+ only.

That's interesting. Thanks for the explanation.

I like to point out every now and then how Intel seems to quickly forget about older GPUs, though it's probably not as critical as I make it out to be. And the thing is, time moves so fast that I'm starting to realize that my top machine - a Haswell desktop - is getting old actually. But as long as I get GL 4.3 and ES 3.1, I'm cool. Anything else - GL 4.5 seems doable, ES 3.2 maybe?, Vulkan 1.0 - is a nice bonus. Especially Vulkan, it's nice to see you're putting in an effort to get that running on Haswell.

[Veerappan]

Gusar I'm running on Haswell on my work laptop (just bought it last fall due to IT department tomfoolery and my requirements for a dev machine). I have at least been able to run some simple vulkan demos using a hand-built mesa-git checkout, but it's not totally there yet (lots of TODO/FINISHME log lines in the console output). But it has at least been started and it seems like something that the Intel guys intend to keep working on when they have a chance.

With regards to GL levels, the people at Igalia (who finished the FP64 work for intel after Connor started a bit of it) do have WIP patches for FP64 for Haswell, but there's still some test regressions/failures/hangs that I think they needed to track down before they submitted the patches for upstream mesa. Given the 11.3/12.0 deadline that was coming up, they focused on merging the chipsets that were working, and plan on trying to finish Haswell when they can.