Since 4.24(.0 / .1 / .2), resizing the mirror window (including full-screening) does not actually resize the target-texture / “viewport” (probably the wrong terminology). The actual mirrored texture just remains the same size, and black bars extend around it. I would love to help resolve this bug, but all my efforts so far have proven useless. I think I am looking into the wrong pieces of code. Any advice on where I would look? It works just fine in 4.23.
Even if I entirely circumvent the call to FSlateApplication::OnSizeChanged in 4.23 - which seems to be the initial entry point to communicate the new window size -, the mirror still correctly resizes… Which boggles my mind. So it can’t be any of the logic related to resizing the D3D11Viewport… Perhaps there is some code somewhere that actually decides how any given texture is “stretched” across the viewport?
Thanks in advance!
All the best,