pointer_lock library

Locks the mouse pointer in place and reports its motion as relative deltas.

Flutter exposes no pointer lock on any desktop platform, which makes a first-person camera impossible out of the box: the cursor reaches the edge of the window and the view stops turning.

Pull, not push

The delta is drained with PointerLock.takeDelta rather than delivered by a stream. That is the shape a game wants. A simulation running on a fixed timestep asks "how far did the mouse move since the last step" once per step; handing it a stream of individual mouse events only moves the accumulation into every caller, and each of them has to get it right.