On Wayland the compositor is in sole control of user input and a client can't influence the cursor positions at all. There are still use cases where the cursor should not be able to escape a particular region or not move at all.

For this exists the pointer constraints protocol. It covers confined and locked cursors

Locked pointer:

• activates once pointer is inside a specified region of the window (can be the whole window)
• once activated the actual system cursor does not move at all (also wl_pointer.motion events are send)
• however the application can get information of the movement of the physical mouse by using the relative pointer protocol and draw a custom cursor if needed
• potential use cases: Games, remote control

Confined pointer:

• activates once pointer is inside a specified region of the window (can be the whole window)
• once activated the cursor cant escape the region
• use cases: VM, remote session, remote control

Wayland objects needed here are: wl_pointer which is availabel in QNativeInterface::QWaylandApplication and wl_surface in QNativeInterface::Private::QWaylandWindow