https://bugs.winehq.org/show_bug.cgi?id=43479
--- Comment #10 from Pekka Helenius fincer89@hotmail.com ---
From user Zootal:
"There seems to be a limit to how many textures can be displayed at once. If you are in a small enclosed area, the graphics can look pretty good, but if you walk outside to a large area, it will drop a lot."
https://appdb.winehq.org/objectManager.php?sClass=version&iId=33591