Thanks for the report!
Can you upload a save where you're standing at that spot?
Of course here you go:
https://drive.google.com/file/d/1LyGowCEe9USqW_dPPv4vbnhh8yLKErZn/view?usp=sharing
The file also contains my UserOptions.ini in case it matter and some Shader.Cache which seems to be done by the game itself in case it matters as well.
Edit:
The game expects these files do be located at:
drive_c/users/your-user-name/Meine Dokumente/gothic3/
or in terms of an English wine prefix it should be at:
drive_c/users/your-user-name/My Documents/gothic3/
i can reproduce the visual artifacts.
The game is rendering to and reading from the same texture. That's technically illegal in Vulkan and our workaround apparently doesnt do the trick.
This is interesting because this issue wasn't present in older versions of Nvidia drivers, like for me on Windows drivers 460+ are the culprit (which coincidentally came out early December 2020 which is when OP started noticing this issue.)
I have a video of the issue happening in Dead Space 2 along with screenshots to confirm it is the same exact issue.
Video: https://www.youtube.com/watch?v=aKgHviJi8bs
Screenshot: https://i.imgur.com/QH1qLyG.png
Can you make an apitrace of that Dead Space 2 issue? Maybe that's easier to debug. (and I'll probably be a bit more motivated as Dead Space 2 is one of my favorites)
I hope this captured it clearly. It's hard to tell when rendering in native D3D9 and the issue isn't visible. But it should do it: https://drive.google.com/file/d/1aiP_jdQDmY_49ZTRYuMFjBWzwf5w03Ze/view?usp=sharing
I updated to the most recent dev build and this problem is resolved for me. No more coronas appearing through the walls, no more blocky rendering artifacts over stacked transparency effects.
The Dead Space 2 issue is fixed by b9360bacc27c30f413e154f4448cb812195d58c5
I can still reproduce the problem in Gothic 3 but the game is also doing something that's highly problematic.
(Blending + Sampling the same texture)
I think this might have been fixed in newer Nvidia drivers? I can atleast not reproduce this at the same location with the 470 driver (earliest i can install without going crazy). This is on a 960 with 1.7.3 and gothic 3 with community patch and highest graphics settings.
Gonna close this. If it works, great, if it doesn't that comes down to a known issue. It's a feedback loop (with blending).
Nothing extracted yet.
Hello you wonderful people,
I witnessed some visual artifacts at some particles in some DirectX 9 games in this case Gothic 3 Enhanced Edition with Community Patch 1.75 as you can see in the screenshots.
In Dead Space 2 I also sometimes spotted some of these artifacts but wasn't able to reproduce it for this ticket they just looked exactly the same and appeared on the flashlight particle effect when aiming an standing close to some surfaces.
Those artifacts are pretty minor and not a big deal after all so no hurry. :)
WineD3D:

DXVK:

Software information
Gothic 3 - Max Settings
System information
Apitrace file(s)
https://drive.google.com/file/d/1HfjcrcaDT9EGuoRSt83rlNQ7fZI4cCg6/view?usp=sharing
Log files