Update DPI scale factor when window is moved to a different X11 output

[jansol]

Check for existing issues

• Completed

Describe the feature

Apparently that is not being done right now, as per #21816 . I remember seeing winit do this way back when I still used X11 so it should be possible?

Environment

Linux/X11

If applicable, add mockups / screenshots to help present your vision of the feature

No response

[notpeter]

I think these are required APIs. Not sure exactly how to determine when a given Zed window is "on" a given display. Currently scaling (ui_font_size / buffer_font_size / zoom) are global across a given Zed process and cannot be adjusted per-window.

X11:

• XRRGetOutputInfo -> XRROutputInfo.mm_width / mm_height
• XRRGetScreenResourcesCurrent(dpy, window) -> XRRScreenResources.modes -> XRRModeInfo.width / height

Wayland:

• wayland_client::protocol::wl_output::Event::Mode.width / height
• wayland_client::protocol::wl_output::Event::Scale.scale
• wayland_client::protocol::wl_output::Event::Geometry.physical_width / physical_height

macOS:

• CGDisplayScreenSize -> CGSize.width / height (in mm)
• CGDisplayPixelsWide / CGDisplayPixelsHigh (in pixels)

[jansol]

I believe on macOS one should simply use the NSWindow backing store scale as that also accounts for user-configured display scaling.