The option Always center window to screen in the Level Editor - Play config section doesn’t work anymore.
The new window is not centered and a border is visible on the screen. Previously, this option would mimic full screen when displaying a new PIE window and using the same resolution as the desktop.
Also, it’s not possible anymore to enter negative values in the New Window Position parameters(probably why the Always Center Windows to screen option is not working anymore, since it must use negative values in order to hide the window borders).
If you choose “Selected Viewport (PIE)” and hit F11 on your keyboard it will simulate full screen as you’ve described. If there is a reason you need it to play full screen in a new editor window, let me know and I will inquire about this change.
Unfortunately, it’s not really the same. When in full screen mode using this mode (F11), the task bar is visible at the bottom. For UI design, it’s not convenient. I’d really prefer to have the previous mode functional like it was until the bug in 4.10. And also, especially while doing UI design and icon and text placement, it’s kinda annoying to have to press F11 each time (lot’s of back and forth to test in-game X F11). The framerate is also much slower when using this mode, I get about half the framerate that I get in new PIE window (110 vs 70 fps).
According to the Developer who worked on this issue: "The regression has been fixed; the behavior is now equal to 4.9. Centered PIE windows are now allowed to overlap work area bounds to give the impression of fullscreen.
However, to clarify, this is not ‘proper’ fullscreen and the window title bar may still be seen at the top (this is because the window border is bigger at the top than the bottom, and centering it will bias towards the top of the window and show half of the title bar).
The following are my results testing in UE4.9, 4.10, 4.11 and 4.12
Always Center Screen Notes:
Editor Preferences for all versions:
*Play in New Window, 1900 x 1200 (Native Resolution) “Always center widow to screen” selected.
Action for all versions: Play > New Editor Window
Results:
UE 4.9 : Window is Centered Horizontally and Vertically UE4 Title Bar Present at Top Windows Task Bar Present at Bottom of Screen regardless of position
UE 4.10 : Window is Left Justified; UE4 Title Bar Present at Top Windows Taskbar is present when window is inactive; otherwise hidden when window is active
UE 4.11 : Window is Centered Horizontally and Vertically UE4 Title Bar NOT Present at Top Windows Task Bar Present at Bottom of Screen regardless of position
UE 4.12 : Window is Centered Horizontally and Vertically UE4 Title Bar Present at Top Windows Task Bar Present at Bottom of Screen regardless of position