SDL2 Linux Wayland DPI scale regression on 2.32.52

[fililip]

DPI scale is correctly reported as 2 with 200% scaling on 2.32.50.
However, on 2.32.52, it's misreported as 1 no matter the scaling factor.

[slouken]

@Kontrabant, any insight here?

[Kontrabant]

The version is 2.32.52, so sdl2-compat is being used here, and the change is due to making theSDL_VIDEO_WAYLAND_SCALE_TO_DISPLAY hint active by default, which hides desktop scaling from the client app/game.

[Kontrabant]

@fililip, if you know of an SDL2 app/game that handles scaling, it can be added to the internal sdl2-compat list to disable this hint, or you can set SDL_VIDEO_WAYLAND_SCALE_TO_DISPLAY=0 in your envvars to permanently disable this behavior everywhere.

[fililip]

Thanks, this env-var works exactly how I need it to!

[slouken]

Was this affecting your code, or a game you installed?

[fililip]

It was affecting my app, which is based on tetra - get_dpi_scale returns 1.0 with that envvar set to 1.

Tetra calculates DPI scale using this formula:

self.sdl_window.drawable_size().0 as f32 / self.sdl_window.size().0 as f32

Maybe there's a better way to do it?