Private Ramp1(0 To 255, 0 To 2) As Integer
Private Ramp2(0 To 255, 0 To 2) As Integer
Private Declare Function GetDeviceGammaRamp Lib "gdi32" (ByVal hdc As Long, lpv _
  As Any) As Long
Private Declare Function SetDeviceGammaRamp Lib "gdi32" (ByVal hdc As Long, lpv _
As Any) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" ( _
Destination As Any, Source As Any, ByVal Length As Long)
 
Private Sub Form_Load()
Dim lVal As Long
Dim iCtr As Integer
 
GetDeviceGammaRamp Me.hdc, Ramp1(0, 0)
 
For iCtr = 0 To 255
lVal = Int2Lng(Ramp1(iCtr, 0))
Ramp2(iCtr, 0) = Lng2Int(Int2Lng(Ramp1(iCtr, 0)) / 2)
Ramp2(iCtr, 1) = Lng2Int(Int2Lng(Ramp1(iCtr, 1)) / 2)
Ramp2(iCtr, 2) = Lng2Int(Int2Lng(Ramp1(iCtr, 2)) / 2)
Next iCtr
Debug.Print SetDeviceGammaRamp(Me.hdc, Ramp2(0, 0))
 
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
SetDeviceGammaRamp Me.hdc, Ramp1(0, 0)
End Sub
 
Public Function Int2Lng(IntVal As Integer) As Long
    CopyMemory Int2Lng, IntVal, 2
End Function
 
Public Function Lng2Int(Value As Long) As Integer
    CopyMemory Lng2Int, Value, 2
End Function