Sub pictureBoxInteract(ByVal intPicBoxX, ByVal intPicBoxY)
        If intOriginalPosX = Nothing And intOriginalPosY = Nothing Then
            intOriginalPosX = intPicBoxX - 1
            intOriginalPosY = intPicBoxY - 1
            strColourSubstring = Strings.Left(arrBoard(intOriginalPosX, intOriginalPosY), 2)
            If boolWhiteTurn = True Then
                If strColourSubstring = "WH" Then
                    boolWhiteTurn = False
                Else
                    MsgBox("It is the white players' turn.", MsgBoxStyle.DefaultButton1, "Invalid Move")
                    intNewPosX = Nothing
                    intNewPosY = Nothing
                    intOriginalPosX = Nothing
                    intOriginalPosY = Nothing
                End If
            Else
                If strColourSubstring = "BL" Then
                    boolWhiteTurn = True
                Else
                    MsgBox("It is the black players' turn.", MsgBoxStyle.DefaultButton1, "Invalid Move")
                    intNewPosX = Nothing
                    intNewPosY = Nothing
                    intOriginalPosX = Nothing
                    intOriginalPosY = Nothing
                End If
            End If

        Else
            intNewPosX = intPicBoxX - 1
            intNewPosY = intPicBoxY - 1

            If checkValid() = True And Not arrBoard(intOriginalPosX, intOriginalPosY) = Nothing Then
                arrBoard(intNewPosX, intNewPosY) = arrBoard(intOriginalPosX, intOriginalPosY)
                arrBoard(intOriginalPosX, intOriginalPosY) = Nothing
                intNewPosX = Nothing
                intNewPosY = Nothing
                intOriginalPosX = Nothing
                intOriginalPosY = Nothing
            Else
                MsgBox("Invalid move. Please try again.", MsgBoxStyle.DefaultButton1, "Invalid Move")
                intNewPosX = Nothing
                intNewPosY = Nothing
                intOriginalPosX = Nothing
                intOriginalPosY = Nothing
            End If
        End If
        Call updateBoard()
    End Sub