mopoidball.h

一款大砖块的游戏

/*
* ============================================================================
*  Name     : TBall from MopoidBall.h
*  Part of  : Mopoid
*  Created  : 16.01.2004 by Andreas Jakl / Mopius - http://www.mopius.com/
*  Description:
*     Handles the ball of the Mopoid game.
*  Version  : 1.02
*  Copyright: 
*     'Mopoid' 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.
* 
*     'Mopoid' is distributed in the hope that it
*     will be useful, but WITHOUT ANY WARRANTY; without even the implied
*     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*     See the GNU General Public License for more details.
* 
*     You should have received a copy of the GNU General Public License
*     along with 'Mopoid'; if not, write to the Free Software
*     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
* ============================================================================
*/

#ifndef __MOPOIDPANEL_H__
#define __MOPOIDPANEL_H__

#include <e32std.h>
#include <e32math.h>
#include "MopoidPanel.h"
#include "MopoidGrid.h"

class TBall {
public:
	TBall();
    
    enum TCollisionOffset {
        ELeft = -1,
        ECenter,
        ERight
    };

    /**
     * Calculate the next position of the ball using its current speed, taking
     * the time difference to the last frame (parameter) into account. The new 
     * location information will be stored in iPosNew (TPoint), iXnew and iYnew (TReal).
     * @param aStep time difference to the last frame
     * @return ETrue if the ball hit a wall and was reflected, otherwise EFalse.
     */
    TBool Move(TReal aStep);

    /**
     * Copies the next position that was calculated by the Move-function to the current
     * coordinates.
     */
    void ConvertToPos();

    /**
     * Checks if the ball is currently colliding with the panel. If it is, the ball will
     * be reflected according to where it hit the panel.
     * @param aPanel contains information about the panel.
     * @param aStep time difference to the last frame
     * @return ETrue if the ball hit the panel and was reflected, otherwise EFalse.
     */
    TBool CheckPanelCollision(const TPanel& aPanel, TReal aStep);

    /**
     * Checks if the ball hits a brick of the grid. If yes, the according event will
     * be sent to the grid so that it will handle the brick hit. The ball will be
     * reflected.
     * @param aGrid contains information about the grid and its bricks.
     * @param aStep time difference to the last frame
     * @return information about the brick that was hit. If no brick was hit, it will
     * return an empty brick with the type EBrickInactive.
     */
    TBrick::TBrickType CheckBrickCollision(TMopoidGrid& aGrid, TReal aStep, TCollisionOffset aSide);

    /**
     * Checks if our ball has fallen below the lower border of the panel.
     * @param aPanel the panel information object.
     * @return ETrue if the ball is dead (below panel), EFalse otherwise.
     */ 
    TBool CheckDeath(const TPanel& aPanel);

private:
    /**
     * Reflect the ball at the x- and y-axis.
     */
    void BounceXY();

    /**
     * Reflect the ball at the x-axis.
     */
    void BounceX();
    
    /**
     * Reflect the ball at the y-axis.
     */
    void BounceY();
    
    /**
     * Make ball faster in x-direction.
     */
    void SpeedUpX();
    
    /**
     * Make ball faster in y-direction.
     */
    void SpeedUpY();

public:
    /**
     * Current screen position of the ball.
     */
	TPoint iPos;

    /**
     * Next position of the ball, calculated by Move().
     */
	TPoint iPosNew;
    
    /**
     * Current exact position of the ball (x-axis).
     */
    TReal iX;
    
    /**
     * Current exact position of the ball (y-axis).
     */
    TReal iY;
    
    /**
     * Next exact position of the ball (x-axis).
     */
    TReal iXnew;
    
    /**
     * Next exact position of the ball (y-axis).
     */
    TReal iYnew;
    
    /**
     * Speed in x-direction.
     */
	TReal iVx;
    
    /**
     * Speed in y-direction.
     */
	TReal iVy;
    
    /**
     * Size of the ball bitmap.
     */
	TSize iSize;
    
    /**
     * Size of the ball bitmap divided by 2 (to speed up calculations which need this).
     */
	TSize iSizeHalf;

};



#endif