I finally got the game running with Vulkan enabled on my AMD Radeon RX 5700. I did the following.
- Upgraded to the latest stable MESA Driver Release 20.1.1
- Entered the following startoption for the game:
-force-vulkan -gfx-enable-gfx-jobs 0
In addition to that ACO can be enabled. The startoption is as follows:
RADV_PERFTEST=aco %command% -force-vulkan -gfx-enable-gfx-jobs 0
This solves the gamecrash with the MESA RADV Vulkandriver. Using vulkan without ACO enabled removes the textureflickering when ambient occlusion is set above very low. Performance seems to be the same as with OpenGL and the stuttering presists.
With ACO enabled the game runs smoother and the occasionally stuttering is gone. However using ACO introduces new weird graphical glitches on my system that appear from time to time.
For now it would be the best if the developers could get the OpenGL renderer to a point where it delivers a solid and stutterfree performance and ambient occlusion could be enabled without causing textureflickering. Hopefully the developers will have a look at the problems with the AMDGPU+MESA drivers. Vulkansupport might be something that can be added later.