A星算法(游戏寻路算法)的C++实现（转）

 

    A星算法的实现原理看这里：http://www.cnblogs.com/technology/archive/2011/05/26/2058842.html

    实现部分：

    头文件：

/*
    A star 算法的基础处理
*/
#ifndef _A_STAR_BASE_H_
#define _A_STAR_BASE_H_
#include "windows.h"

typedef struct _APoint{
    int x; // x 坐标
    int y; // y 坐标
    int type; // 类型
    int f; // f = g + h
    int g;
    int h;
} APoint,*PAPoint;

enum APointType{
    APT_UNKNOWN, // 未知状态
    APT_OPENED, // 开放列表中
    APT_CLOSED, // 关闭列表中
    APT_STARTPOINT, // 起始点
    APT_ENDPOINT // 结束点
};


class CAStarBase{
public:
    CAStarBase();
    ~CAStarBase();
private:
    PAPoint m_pAPointArr;
    int m_nAPointArrWidth;
    int m_nAPointArrHeight;

    PAPoint m_pStartPoint,m_pEndPoint,m_pCurPoint;
    char* m_pOldArr;
public:
    BOOL Create(char* pDateArr,int nWidth,int nHeight);
    void SetStartPoint(int x,int y);
    void SetEndPoint(int x,int y);
    void SetOpened(int x,int y);
    void SetClosed(int x,int y);
    void SetCurrent( int x,int y );
    void PrintCharArr();

    PAPoint CalcNextPoint(PAPoint ptCalc); // 应用迭代的办法进行查询
};

#endif

实现cpp文件：

#include "stdafx.h"
#include "AStarBase.h"


CAStarBase::CAStarBase()
{
    m_pAPointArr = NULL;
    m_nAPointArrWidth = 0;
    m_nAPointArrHeight = 0;

    m_pStartPoint = NULL;
    m_pEndPoint = NULL;
    m_pCurPoint = NULL;

}

CAStarBase::~CAStarBase()
{

}

BOOL CAStarBase::Create( char* pDateArr,int nWidth,int nHeight )
{
    if(!pDateArr) return FALSE;
    if(nWidth<1 || nHeight<1) return FALSE;
    m_pAPointArr = new APoint[nWidth*nHeight];
    if(!m_pAPointArr) return FALSE;
    m_pOldArr = pDateArr;
    m_nAPointArrWidth = nWidth;
    m_nAPointArrHeight = nHeight;
    // 初始化数组内容
    for ( int y = 0;y<m_nAPointArrHeight;y++)
    {
        for ( int x=0;x<m_nAPointArrWidth;x++)
        {
            m_pAPointArr[y*m_nAPointArrWidth+x].x = x;
            m_pAPointArr[y*m_nAPointArrWidth+x].y = y;
            m_pAPointArr[y*m_nAPointArrWidth+x].g = 0;
            m_pAPointArr[y*m_nAPointArrWidth+x].f = 0;
            m_pAPointArr[y*m_nAPointArrWidth+x].h = 0;

            if ( pDateArr[y*m_nAPointArrWidth+x] == '0')
            {
                m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_OPENED;
            }else if ( pDateArr[y*m_nAPointArrWidth+x] == '1')
            {
                m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_CLOSED;
            }else if ( pDateArr[y*m_nAPointArrWidth+x] == 'S')
            {
                m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_STARTPOINT;
                m_pStartPoint = m_pAPointArr + y*m_nAPointArrWidth+x;
                m_pCurPoint = m_pStartPoint;
            }else if ( pDateArr[y*m_nAPointArrWidth+x] == 'E')
            {
                m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_ENDPOINT;
                m_pEndPoint = m_pAPointArr + y*m_nAPointArrWidth+x;
            }else{
                m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_UNKNOWN;
            }

        }
    }
    return TRUE;
}

void CAStarBase::SetStartPoint( int x,int y )
{
    if ( m_pStartPoint && m_pAPointArr[y*m_nAPointArrWidth+x].type!=APT_CLOSED )
    {
        m_pStartPoint->type = APT_OPENED;
        // 设置新的值
        m_pStartPoint = m_pAPointArr + y*m_nAPointArrWidth+x;
        m_pStartPoint->type = APT_STARTPOINT;
        m_pCurPoint = m_pStartPoint;
    }
}

void CAStarBase::SetEndPoint( int x,int y )
{
    if ( m_pStartPoint && m_pAPointArr[y*m_nAPointArrWidth+x].type!=APT_CLOSED )
    {
        m_pStartPoint->type = APT_OPENED;
        // 设置新的值
        m_pStartPoint = m_pAPointArr + y*m_nAPointArrWidth+x;
        m_pStartPoint->type = APT_ENDPOINT;
    }
}

void CAStarBase::SetCurrent( int x,int y )
{
//  if ( m_pAPointArr[y*m_nAPointArrWidth+x].type==APT_OPENED )
    {
        m_pCurPoint = m_pAPointArr+y*m_nAPointArrWidth+x;
    }
}

void CAStarBase::SetOpened( int x,int y )
{
    if ( m_pAPointArr[y*m_nAPointArrWidth+x].type!=APT_OPENED )
    {
        m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_OPENED;
    }
}

void CAStarBase::SetClosed( int x,int y )
{
    if ( m_pAPointArr[y*m_nAPointArrWidth+x].type!=APT_CLOSED )
    {
        m_pAPointArr[y*m_nAPointArrWidth+x].type = APT_CLOSED;
    }
}

void CAStarBase::PrintCharArr()
{
    if ( m_pOldArr )
    {
        for ( int y=0; y<m_nAPointArrHeight;y++)
        {
            for ( int x=0;x<m_nAPointArrWidth;x++)
            {
                printf("%c ",m_pOldArr[x+m_nAPointArrWidth*y]);
            }
            printf("
");
        }
        printf("
");
    }
}

PAPoint CAStarBase::CalcNextPoint( PAPoint ptCalc )
{
    if ( ptCalc == NULL )
    {
        ptCalc = m_pStartPoint;
    }
    int x = ptCalc->x;
    int y = ptCalc->y;
    int dx = m_pEndPoint->x;
    int dy = m_pEndPoint->y;
    int xmin = x,ymin = y,vmin = 0; // 最优步骤的坐标和值
    // 判断是否已经到了最终的位置
    if ( (x==dx && abs(y-dy)==1) || (y==dy && abs(x-dx)==1) )
    {
        return m_pEndPoint;
    }
    // 上
    if ( m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].type == APT_OPENED && y>0)
    {
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].g = 10;
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].h =
            10*(abs(x - dx) + abs(y-1 - dy));
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].f =
            m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].g + m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].h;
        if ( vmin==0 )
        {
            xmin = x;
            ymin = y-1;
            vmin = m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].f;
        }else{
            if ( vmin > m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].f )
            {
                xmin = x;
                ymin = y-1;
                vmin = m_pAPointArr[(x+0)+m_nAPointArrWidth*(y-1)].f;
            }
        }
    }
    // 下
    if ( m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].type == APT_OPENED && y<m_nAPointArrHeight)
    {
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].g = 10;
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].h =
            10*(abs(x - dx) + abs(y+1 - dy));
        m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].f =
            m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].g + m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].h;
        if ( vmin==0 )
        {
            xmin = x;
            ymin = y+1;
            vmin = m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].f;
        }else{
            if ( vmin > m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].f )
            {
                xmin = x;
                ymin = y+1;
                vmin = m_pAPointArr[(x+0)+m_nAPointArrWidth*(y+1)].f;
            }
        }
    }
    // 左
    if ( m_pAPointArr[(x-1)+m_nAPointArrWidth*y].type == APT_OPENED && x>0)
    {
        m_pAPointArr[(x-1)+m_nAPointArrWidth*y].g = 10;
        m_pAPointArr[(x-1)+m_nAPointArrWidth*y].h =
            10*(abs(x-1 - dx) + abs(y - dy));
        m_pAPointArr[(x-1)+m_nAPointArrWidth*y].f =
            m_pAPointArr[(x-1)+m_nAPointArrWidth*y].g + m_pAPointArr[(x-1)+m_nAPointArrWidth*y].h;
        if ( vmin==0 )
        {
            xmin = x-1;
            ymin = y;
            vmin = m_pAPointArr[(x-1)+m_nAPointArrWidth*y].f;
        }else{
            if ( vmin > m_pAPointArr[(x-1)+m_nAPointArrWidth*y].f )
            {
                xmin = x-1;
                ymin = y;
                vmin = m_pAPointArr[(x-1)+m_nAPointArrWidth*y].f;
            }
        }
    }
    // 右
    if ( m_pAPointArr[(x+1)+m_nAPointArrWidth*y].type == APT_OPENED && x<m_nAPointArrWidth)
    {
        m_pAPointArr[(x+1)+m_nAPointArrWidth*y].g = 10;
        m_pAPointArr[(x+1)+m_nAPointArrWidth*y].h =
            10*(abs(x+1 - dx) + abs(y - dy));
        m_pAPointArr[(x+1)+m_nAPointArrWidth*y].f =
            m_pAPointArr[(x+1)+m_nAPointArrWidth*y].g + m_pAPointArr[(x+1)+m_nAPointArrWidth*y].h;
        if ( vmin==0 )
        {
            xmin = x+1;
            ymin = y;
            vmin = m_pAPointArr[(x+1)+m_nAPointArrWidth*y].f;
        }else{
            if ( vmin > m_pAPointArr[(x+1)+m_nAPointArrWidth*y].f )
            {
                xmin = x+1;
                ymin = y;
                vmin = m_pAPointArr[(x+1)+m_nAPointArrWidth*y].f;
            }
        }
    }

    // 如果有最优点则迭代，则否就返回NULL
    if ( vmin )
    {
        SetCurrent(xmin,ymin);
        SetClosed(xmin,ymin);
        *(m_pOldArr+xmin+m_nAPointArrWidth*ymin) = '-';
        PrintCharArr();
        PAPoint pApoint = CalcNextPoint(m_pCurPoint);
        if ( pApoint == NULL )
        {
            SetCurrent(x,y);
            SetClosed(xmin,ymin);
            *(m_pOldArr+xmin+m_nAPointArrWidth*ymin) = '0';
            return CalcNextPoint(m_pCurPoint);
        }
        return pApoint;
    }else{
        return NULL;
    }

}

测试文件：

// AStarMath.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include "AStarBase.h"

CAStarBase Astarbase;

int _tmain(int argc, _TCHAR* argv[])
{
    char pBuff[5][7] = {
        '0','0','0','1','0','0','0',
        '0','1','1','0','0','1','1',
        '0','S','1','0','1','E','0',
        '0','1','0','0','0','1','0',
        '0','0','0','1','0','0','0'
    };
    Astarbase.Create(&pBuff[0][0],7,5);
    Astarbase.PrintCharArr();
    PAPoint pPoint = Astarbase.CalcNextPoint(NULL);
    if ( pPoint == NULL )
    {
        printf("no path can arrive!
");
    }else{
        printf("success arrived!
");
    }
    getchar();
    return 0;
}