; This script is based on Bkid's script.

#Persistent
#NoEnv
#SingleInstance ignore

Menu, Tray, NoStandard ; Removes Tray Menu Standard Items.
Menu, Tray, Add, Exit, ExitSub ; Adds an 'Exit' menu

; Hotkey to be used depends of the coder.
SetScrollLockState, Off ; Makes the capslock state off.
TrayTip, Mouse Capture, Press ScrollLock to start/stop mouse capture., 10 ; Tray tip notice
SetTimer, Label, 5 ; Turns on the timer with 5 milliseconds check.  
return

ExitSub:
ExitApp ; Exits the application

; The label which will call the function.
; This is only a sample. You can change them in any way you want.
Label:
GetKeyState, State, ScrollLock, T
if(State = "D"){
  WinCapture("ahk_class Warcraft III", "", 4, 4, 24) ; See the function below.
  WinActivate, ahk_class Warcraft III ; Activates the script.
  Suspend, Off ; Activates the script.
  TrayTip, Mouse Capture, Mouse Capture activated. Press ScrollLock to stop., 10 ; Tray tip notice
}else{
  WinCapture()
  Suspend, On ; Suspends the script
  TrayTip, Mouse Capture, Mouse Capture deactivated. Press ScrollLock to start., 10 ; Tray tip notice
}
return
; Make a function to call for locking the mouse into a window.
; Syntax of the function:
; WinCapture("WinTitle", "WinText", "vBorder", "hBorder", "tBorder")
; WinTitle = The title or class of the window. Use ahk_class if window's class will be used.
; WinText = If present, this parameter must be a substring from a single text element of the target window.
; vBorder = The vertical border. The left and right borders of a window. Commonly about 4 pixels in size.
; hBorder = The horizontal border. The bottom border of a window. Commonly about 4 pixels in size.
; tBorder = The title bar border. Commonly about 24 pixels in size.

; The function.
WinCapture(WinTitle = "", WinText = "", vBorder = "", hBorder = "", tBorder = "") ; => Start of function.
{
  ; Enlarges a variable's holding capacity or frees its memory. Normally, this is necessary only for unusual circumstances such as DllCall.
  VarSetCapacity(VarSetA, 16)
  ; Gets the position of the window.
  WinGetPos, sX, sY, sWidth, sHeight, %WinTitle%, %WinText%
  if(!sWidth and !sHeight){
  DllCall("ClipCursor")
  return, False
  }
  Loop, 4 {
  ; DLL Calls
  DllCall("RtlFillMemory", UInt,&VarSetA+0+A_Index-1, UInt,1, UChar,(sX + hBorder) >> 8*A_Index-8)
  DllCall("RtlFillMemory", UInt,&VarSetA+4+A_Index-1, UInt,1, UChar,(sY + tBorder) >> 8*A_Index-8)
  DllCall("RtlFillMemory", UInt,&VarSetA+8+A_Index-1, UInt,1, UChar,(sWidth + sX - vBorder)>> 8*A_Index-8)
  DllCall("RtlFillMemory", UInt,&VarSetA+12+A_Index-1, UInt,1, UChar,(sHeight + sY - vBorder) >> 8*A_Index-8)
  }
  DllCall("ClipCursor", "UInt", &VarSetA)
  return, True
} ; End of function.