osu-alternate.ahk

SendMode Input
SetWorkingDir, %A_ScriptDir%
#SingleInstance, Force
#IfWinActive, ahk_exe osu!.exe

Thread, interrupt, 0 ; ensure no delay on keypresses

global prev := 0, zDown := false, xDown := false

CheckAlternate(cur)
{
  if (prev = cur)
  {
    SoundPlay, combobreak.wav ; You can just replace to .wav itself or change it here
  }
  prev := cur
}

SetTimeout:
  SetTimer, Timeout, -5000 ; Five-second timeout, can change to whatever. Make sure it stays negative.
return

; Change these to whatever keys you use

~W::
  Gosub, SetTimeout
  if (zDown)
  {
    return
  }
  CheckAlternate(-1)
  zDown := true
return

~W Up::zDown := false

~D::
  Gosub, SetTimeout
  if (xDown)
  {
    return
  }
  CheckAlternate(1)
  xDown := true
return
~D Up::xDown := false

; These keys reset the alternation. You can change or just remove them if you want.
~Escape::
~LShift::
  prev := 0
return

Timeout:
  prev := 0
  SetTimer, Timeout, Off
return