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：

[cpp] view plain copy

/*

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：

[cpp] view plain copy







#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("\r\n");

}

printf("\r\n");

}

}

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：

[cpp] view plain copy







// 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!\r\n");

}else{

printf("success arrived!\r\n");

}

getchar();

return 0;

}