File indexing completed on 2024-10-13 04:15:11

0001 /*
0002  * SPDX-FileCopyrightText: (C) 2020 Carl Schwan <carl@carlschwan.eu>
0003  *
0004  * SPDX-License-Identifier: LGPL-2.1-or-later
0005  */
0006 
0007 #pragma once
0008 
0009 class QImage;
0010 
0011 /**
0012  * A class implementing the command pattern. This is used to implemented various filters.
0013  */
0014 class UndoCommand
0015 {
0016 public:
0017     virtual ~UndoCommand() = 0;
0018 
0019     /**
0020      * Applies the change to the document.
0021      */
0022     virtual QImage redo(QImage image) = 0;
0023 
0024     /**
0025      * Revert a change to the document.
0026      */
0027     virtual QImage undo(QImage image) = 0;
0028 };