Vulkan Wayland Compositors Are Nearing Reality

[iskra32]

That's interesting. I would be interested in the 'tricks to reduce input latency'. Any pointers?

Thanks for the reply!

I am not certain how other compositors do it, but Kwin(once 5.21 releases of course) for example estimates how long compositing will take based on past frames, and then does it just in time before a vblank. This means that hypothetically there shouldn't be *any* latency beyond the usual(and unavoidable due to how displays work) delay between frames.

[mdedetrich]

while, that's nice. n all. great work. kudos all around.
however, would someone put me out of my misery and tell me WHY we need 3d for desktop?
What's wrong with the fastest path, cpu? like we've been doing for years. (with or without buggy 2d accel).
And i don't mean the software emulated compositor. . Unless you're going to tell me it's as fast and responsive as.
Is it just the resolutions we use these days or what?
(I don't care for stupid fancy effects, i'm looking for some technical reasons beyond eye candy)

Considering that most of you are using a composited desktop i expect a lot of considered responses.

Actually the main benefits have little to do with being 3D and more

• Vuilkan was designed with multi threading/parallelism in mind which means it will make it easier to do smoother/responsive compositing by delegating work on multiple threads
• Vulkan is a lot lower level than OpenGL which ultimately gives more control to programmers allowing them to squeeze more performance

My response is assuming we are making a comparison to OpenGL on a GPU, if we are dealing with CPU compositing than Vulkan will be much much faster and responsive

[reba]

On top: Vulkan has a CPU-only implementation "Lavapipe" (Phoronix article).

While this might create an additional overhead it should make even the weirdest platform (with or without a GPU at all) Vulkan-compatible and thus - makes every Vulkan-based application (e.g. here: compositors) available to the user.

Even the ones who bought into nvidia will have this absolute fallback available to them, no matter what.

Disclaimer: that is, if I understood their project correctly


Edit:
Holy Moly, it actually works - spinning cubes!

[FONT=monospace][COLOR=#000000]$ VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/lvp_icd.x86_64.json vkcube [/COLOR]
WARNING: lavapipe is not a conformant vulkan implementation, testing use only.[/FONT]

Oh yeah, and Quake of course: https://www.youtube.com/watch?v=Goed4wr2jf4

[dragon321]

With dma-buf support in Nvidia drivers maybe this will finally solve this Nvidia vs Everyone mess.