SUMMARY When the game hearts of iron 4 is configured to a lower resolution than that of the desktop the remaining screen is filled with artifacts instead of scaled correctly STEPS TO REPRODUCE 1. get hoi4 on steam & install & start 2. go to options 3. change resolution to one lower than the desktop (in my case from 2160 to 1080). display mode is fullscreen FWIW. 4. restart game OBSERVED RESULT output broken, mouse input is also not matching up with the actual correctly painted part of the screen EXPECTED RESULT output should be 1080 SOFTWARE/OS VERSIONS KDE Plasma Version: 6.0.80 KDE Frameworks Version: 6.1.0 Qt Version: 6.6.3 Kernel Version: 6.8.2-arch2-1 (64-bit) Graphics Platform: Wayland Processors: 12 × AMD Ryzen 5 3600X 6-Core Processor Memory: 31.2 GiB of RAM Graphics Processor: AMD Radeon RX 5700 XT ADDITIONAL INFORMATION Parts of the screen seem to redraw somewhat consistently on alt-tabbing revealing that the top left corner is where input gets received but the bottom left corner is the one that gets painted to. I have a three display setup but the two side screens are currently disabled via the kscreen kcm.
screenshot https://imgur.com/a/fzwJeTI
Created attachment 168066 [details] drm_info output while windows is fullscreen
The game seems to get direct scanout, judging by the XRGB8888 format. Given that, this looks quite wrong: │ ├───"SRC_W" (atomic): range [0, UINT32_MAX] = 3840 │ ├───"SRC_H" (atomic): range [0, UINT32_MAX] = 2160
I managed to reproduce this in Half Life 2 and KWin seems to do everything correctly; we get a full resolution buffer from Xwayland... and it's very similar to https://gitlab.freedesktop.org/xorg/xserver/-/issues/1595, so I'm pretty confident it's that Xwayland bug