lock and hide cursor

I add `lock and hide cursor` in my fork for 3d game(like minecraft), but I meet something problem, look at code:
```
override fun setPointerLockable(isLockable:Boolean) {
val robot = Robot()
val mot = object:MouseMotionListener{
override fun mouseMoved(e: MouseEvent?) {
robot.mouseMove(nativeComponent.width/2+nativeComponent.locationOnScreen.x,nativeComponent.height/2+nativeComponent.locationOnScreen.y)
}
override fun mouseDragged(e: MouseEvent?) {
robot.mouseMove(nativeComponent.width/2+nativeComponent.locationOnScreen.x,nativeComponent.height/2+nativeComponent.locationOnScreen.y)
}
}
if(isLockable){
nativeComponent.addMouseMotionListener(mot)
return
}
nativeComponent.removeMouseMotionListener(mot)
}
```
But when I move mouse quickly, I may see the cursor,because the windows is small, cursor move out of windows.
- Are there someway to disable the cursor?

Start at the setPointerLockable override and inspect how nativeComponent handles mouse motion and cursor visibility. Reproduce the fast-movement case in a small desktop 3D game, then verify that locking keeps the cursor hidden or contained and that disabling the lock restores normal cursor behavior.

Written by the indexing model from the issue text.