#NoEnv
SetBatchLines -1
Process Priority,,R

BlockInput Mouse		; user mouse input is ignored during MouseMove
CoordMode Mouse, Screen	; absolute coordinates
SysGet m, Monitor		; get the screen edges
mTop += 1, mBottom -= 2
SetMouseDelay -1		; fastest action

MButton::
Click M Down
MouseGetPos x0, y0		; get initial mouse pointer location
SetTimer WatchMouse, 1	; run the subroutine fast (10..16ms)
Return

MButton Up::
Click M Up
SetTimer WatchMouse, Off
Return

WatchMouse:
   MouseGetPos x, y		; get current mouse position
   y0 += (y0-y), y0 := y0 < mTop ? mTop : (y0 > mBottom ? mBottom : y0)
   MouseMove x, y0, 0	; set new position as old, for the next timer
Return