Since update 371502, I cannot load the game in fullscreen without major graphics glitching (see screenshot). This only happens when in fullscreen mode. Oddly enough, I had to take a photo with my phone because a screenshot introduces OSX UI elements, which for some reason solves the glitching (ie, popups, the dock, etc). ONI is using my high performance graphics card (Radeon Pro 455) and not the integrated graphics card.
When I play in windowed mode, I have no problems. The problem is that I suffer substantial performance degradation when not in fullscreen mode. Up until 371502, I never encountered this issue. I upgraded to Mac OSX Catalina somewhere around the same time as that update, so I suppose it could also be that, but I can't remember the exact chronology. I've tested across all of the resolutions and I have the same issue with each.
I'd appreciate some help fixing it.
Steps to Reproduce
Open up ONI from Steam in fullscreen mode on a 15" Macbook Pro 2016 with a Radeon Pro 455 and OSX Catalina installed.
This issue has been previously reported, please search the bug tracker for more information about this issue.