http://bugs.winehq.org/show_bug.cgi?id=24630
--- Comment #7 from Benj benj.callaghan@gmail.com 2011-09-01 21:11:41 CDT --- Created an attachment (id=36200) --> (http://bugs.winehq.org/attachment.cgi?id=36200) Screenshots comparing the bloom effect
These screenshots show that the artifacting is a direct result of the bloom effect. Starting with a preset with bloom off, the artifacting is visible. Turning bloom on without changing other settings removes the artifacting. Starting with a preset with bloom on, the artfacting is not visible. Turning bloom off without changing other settings activates the artifacting.
The two workarounds to this bug that I've discovered are to turn on bloom, or switch complex shader distance to -1.