Tesded on vkd3d-proton 2.5 using both Proton-6.20-GE-1 and Wine-6.20-GE-1:
Finally, playing with an USB controller fixes the stutter and partially solves flicker, as it only flickers sometimes when you open a menu (inventory, waypoints, options).
Another important point, is that some poeple @ Windows had problems with an OSD, an on-screen display. So disabling Mangohud or DXK_HUD is mandatory. I can confirm that at a certain point, with Mangohud the game cannot detect window focus and GPU is at 30-50%, won't hit 90-100% so game starts to drop FPS til' you restart it.
For me the game is enjoyable with freesync + compositor off + USB controller. Any other configuration makes it to feel buggy and slowish.
Os: Arch Linux
Video: amdgpu + radv (Mesa 22.0.0-devel (git-01d36149cd))
Kernel: Linux 5.15.2-zen1-1-zen
The flickering shadows/patterns in the smoke issue on mesa is no longer reproduciable as of mesa 21.3.2 or mesa-git.
@kub0x as your found issues go much deeper than mine (I do not use freesync, or have noticed the black square artifacts) I'd suggest doing a re-test (using vkd3d-git and mesa-git could see some of them fixed) and creating a new issue, if they are still reproduciable.
proton 2.5x1 2021-11proton 6.20-ge-1x1 2021-11
Description
Smoke and some light emitting objects show flickering shadows and patterns, especially visible when moving.
The issue was much more prominent in VKD3D 2.4. With VKD3D 2.5 it got a lot less noticeable but is still there - see the following screencaps.
Screencaps
VKD3D 2.4: https://streamable.com/qujizr
VKD3D 2.5: https://streamable.com/8i269g
To reproduce
The easiest reproducer is in Dark Wood (an early area of the game). Search for the burning building seen in the screencaps.
Tested on wine-ge-6.20 + mesa-git (4th of November) + RADV on a AMD RX6800.
Tested quite a few graphic options of the game, which had no effect on the issue.
Based on other users feedback this is not reproduciable on Nvidia.