I recently opened a bug (case 1354081) for a problem with exclusive fullscreen. When setting the resolution to the highest supported 16:9 ratio (2560x1440) on a 3440x1440 monitor in exclusive fullscreen we do not see letter boxing on the left and right side. Letterboxing is present on all other resolutions and all other fullscreen modes except Exclusive at highest supported resolution (I believe this also happens on 2K monitors as well). Posting to bump the bug, and see if anyone else experienced this and has any work arounds.
This is generally up to drivers in exclusive fullscreen mode. In FullScreenWindow mode, we draw the borders ourselves, but on exclusive fullscreen we change the display mode to the specified one and let the drivers/OS handle it.
Out of curiosity, why is this use case (16:9 resolution on 21:9) monitor important? Users with ultra wide monitors generally hate when games don’t use full screen space of the display.
The game’s UI was designed for 16:9 is the main reason, it is kind of too late in development to rework the UI to work with more aspect ratios so we were just going to lock it to 16:9 and try our best to prevent players from having a strange looking UI. Seems the answer is there really isn’t anything that can be done?
Yeah, unfortunately exclusive fullscreen is kind of clunky: it’s a legacy technology that came from before Windows desktop manager knew how to efficiently compose apps on the desktop and allow an application to present directly to the screen if it covers the whole screen. As such, we don’t have nearly as much control on exclusive fullscreen mode as we’d like and a lot of it is handled by “black magic” on the OS/driver side.
Microsoft considers it to be superceded by FullScreenWindow mode. This issue should not happen in that mode.
A fair warning here: a lot of PC games get flak for stuff like that. Not saying it’s justified, but it’s just how it is.