Source: ksirk/backgnd.h

/***************************************************************************
                          backgnd.h  -  description
                             -------------------
    begin                : Wed Jul 18 2001
    copyright            : (C) 2001 by Gaël de Chalendar
    email                : Gael.de.Chalendar@libertysurf.fr
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
#define KDE_NO_COMPAT

#ifndef  BACKGND_H
#define BACKGND_H

#include "decoratedgameframe.h"

class DecoratedGameFrame;

/**
 * BackGnd is the sprite used to display the background map image
 * Using a sprite allow to move it quickly on the fixed canvas. As for
 * AnimSprite, the individual images are taken from a Graphics Pool storing
 * all images of the game. In the same time, the graphics pool is the canvas
 * where all sprites (background and animated) are stored. It is viewed by
 * the frame (a DecoratedGameFrame, a kind of CanvasView).
 *
 * The background can be scrolled in the four directions with specialized
 * methods
 */
class BackGnd : public QCanvasSprite
{
public:
	enum TDir {state, right, left, up, down, N, S, E, O, NO, SO, SE, NE};
	
	/**
	 * The QCanvas is the canvas where all the sprites are set up.
	 * aFrame is the view used to display the background.
	 */
	BackGnd(QCanvas *canvas, DecoratedGameFrame *aFrame);
	~BackGnd();
	
	/**
	 * These four scroll methods allow to easilly scroll the background on its
	 * canvas in a simple and transparent manner
	 */
	void scrollUp(const int step = DefaultScrollStep);
	void scrollDown(const int step = DefaultScrollStep);
	void scrollLeft(const int step = DefaultScrollStep);
	void scrollRight(const int step = DefaultScrollStep);

private:
	/**
	 * This static member allow to simplify the call to scroll functions
	 */
	static int DefaultScrollStep;

	/**
	 * The frame is the view on which the background and the animated sprites
	 * are painted.
	 */
	DecoratedGameFrame *frame;

	/**
	 * The scroll method is used by the scrollX public methods to call the
	 * native scrollBy methods in the good direction. Its arguments are a
	 * named direction and a number of pixels step
	 */
	void scroll(TDir dir, int step);
};

#endif //  BACKGND_H