cocos2d - JS A*算法

来源：互联网发布：郑州轻工业网络教学编辑：程序博客网时间：2024/05/18 00:16

创建map对象 :

var map = {       rows : 5,       cols : 5,       arr : [           [0,0,1,0,0],           [0,0,1,0,0],           [0,1,0,0,0],           [0,1,0,1,0],           [0,0,0,1,0],       ]   }   var result = this.searchRoad(map,0,0,4,4)   cc.log(result)

传入A*方法返回的是路径数组

    //其中的MAP.arr是二维数组    searchRoad :function (MAP, start_x, start_y, end_x, end_y){        var openList=[],    //开启列表            closeList=[],   //关闭列表            result=[],      //结果数组            result_index;   //结果数组在开启列表中的序号        openList.push({x:start_x,y:start_y,G:0});//把当前点加入到开启列表中，并且G是0        do{            var currentPoint = openList.pop();            closeList.push(currentPoint);            var surroundPoint=SurroundPoint(currentPoint);            for(var i in surroundPoint) {                var item = surroundPoint[i];                //获得周围的八个点                if (                    item.x >= 0 &&                            //判断是否在地图上                    item.y >= 0 &&                    item.x < MAP.rows &&                    item.y < MAP.cols &&                    MAP.arr[item.x][item.y] != 1 &&         //判断是否是障碍物                    !existList(item, closeList) &&          //判断是否在关闭列表中                    MAP.arr[item.x][currentPoint.y] != 1 &&   //判断之间是否有障碍物，如果有障碍物是过不去的                    MAP.arr[currentPoint.x][item.y] != 1){                    //g 到父节点的位置                    //如果是上下左右位置的则g等于10，斜对角的就是14                    var g = currentPoint.G + ((currentPoint.x - item.x) * (currentPoint.y - item.y) == 0 ? 10 : 14);                    if (!existList(item, openList)) {       //如果不在开启列表中                        //计算H，通过水平和垂直距离进行确定                        item['H'] = Math.abs(end_x - item.x) * 10 + Math.abs(end_y - item.y) * 10;                        item['G'] = g;                        item['F'] = item.H + item.G;                        item['parent'] = currentPoint;                        openList.push(item);                    }                    else {                                  //存在在开启列表中，比较目前的g值和之前的g的大小                        var index = existList(item, openList);                        //如果当前点的g更小                        if (g < openList[index].G) {                            openList[index].parent = currentPoint;                            openList[index].G = g;                            openList[index].F=g+openList[index].H;                        }                    }                }            }            //如果开启列表空了，没有通路，结果为空            if(openList.length == 0) {                break;            }            openList.sort(sortF);//这一步是为了循环回去的时候，找出 F 值最小的, 将它从 "开启列表" 中移掉        }while(!(result_index=existList({x:end_x,y:end_y},openList)));        //判断结果列表是否为空        if(!result_index)         {            result = [];        }        else         {            var currentObj=openList[result_index];            do{                //把路劲节点添加到result当中                result.unshift({                    x:currentObj.x,                    y:currentObj.y                });                currentObj=currentObj.parent;            }while (currentObj.x != start_x || currentObj.y != start_y);        }        return result;    },

全局方法 :

//用F值对数组排序function sortF(a,b){    return b.F - a.F;}//获取周围八个点的值function SurroundPoint(curPoint){    var x = curPoint.x,        y = curPoint.y;    return [        {x:x-1,y:y-1},        {x:x,y:y-1},        {x:x+1,y:y-1},        {x:x+1,y:y},        {x:x+1,y:y+1},        {x:x,y:y+1},        {x:x-1,y:y+1},        {x:x-1,y:y}    ]}//判断点是否存在在列表中，是的话返回的是序列号function existList(point,list) {    for(var i in list)    {        if(point.x == list[i].x && point.y == list[i].y)        {            return i;        }    }    return false;}

完整cocos2d-JS 实例 :
(复制可以直接使用只需要在resource里有三种图片即可)
这里写图片描述

0 : 为可走路径
1 : 为不可走路径
9 : 为主角

//用F值对数组排序function sortF(a,b){    return b.F - a.F;}//获取周围八个点的值function SurroundPoint(curPoint){    var x = curPoint.x,        y = curPoint.y;    return [        {x:x-1,y:y-1},        {x:x,y:y-1},        {x:x+1,y:y-1},        {x:x+1,y:y},        {x:x+1,y:y+1},        {x:x,y:y+1},        {x:x-1,y:y+1},        {x:x-1,y:y}    ]}//判断点是否存在在列表中，是的话返回的是序列号function existList(point,list) {    for(var i in list)    {        if(point.x == list[i].x && point.y == list[i].y)        {            return i;        }    }    return false;}var map = {    rows : 5,    cols : 5,    arr : [        [0,0,1,0,0],        [0,0,1,0,0],        [0,1,0,0,0],        [0,1,0,1,0],        [0,0,0,1,0],    ]}var MyPos = null;var MySprite = null;var HelloWorldLayer = cc.Layer.extend({    ctor:function () {        this._super();        this.Astar();    },    call_Back: function(event,touch){        cc.log("touch",event._parent.AstarX,event._parent.AstarY)        var endX = event._parent.AstarX,            endY = event._parent.AstarY;        var result = this.searchRoad(map,MyPos.x,MyPos.y,endX,endY);        this.schedule(function(){            var road = result.shift()            if(road)            {                var action = cc.moveTo(0.24,240+34*road.y,350-36*road.x);                MySprite.runAction(action);                MyPos = cc.p(road.x,road.y);            }        },0.25)    },    Astar: function(){        MyPos = cc.p(0,0);        for(var i = 0; i < map.rows; i++)        {            for(var j = 0; j < map.cols; j++)            {                var temp = new cc.Menu(new cc.MenuItemImage("res/"+map.arr[i][j]+".png", "res/"+map.arr[i][j]+".png", this.call_Back, this));                temp.setPosition(240+34*j,350-36*i);                temp.AstarX = i;                temp.AstarY = j;                this.addChild(temp);                if(i == 0 && j == 0)                {                    var temp = new cc.Sprite("res/9.png")                    MySprite = temp;                    temp.setPosition(240+34*j,350-36*i);                    this.addChild(temp,1000);                }            }        }    },    //其中的MAP.arr是二维数组    searchRoad :function (MAP, start_x, start_y, end_x, end_y){        var openList=[],    //开启列表            closeList=[],   //关闭列表            result=[],      //结果数组            result_index;   //结果数组在开启列表中的序号        openList.push({x:start_x,y:start_y,G:0});//把当前点加入到开启列表中，并且G是0        do{            var currentPoint = openList.pop();            closeList.push(currentPoint);            var surroundPoint=SurroundPoint(currentPoint);            for(var i in surroundPoint)            {                var item = surroundPoint[i];                //获得周围的八个点                if (                    item.x >= 0 &&                            //判断是否在地图上                    item.y >= 0 &&                    item.x < MAP.rows &&                    item.y < MAP.cols &&                    MAP.arr[item.x][item.y] != 1 &&         //判断是否是障碍物                    !existList(item, closeList) &&          //判断是否在关闭列表中                    MAP.arr[item.x][currentPoint.y] != 1 &&   //判断之间是否有障碍物，如果有障碍物是过不去的                    MAP.arr[currentPoint.x][item.y] != 1){                    //g 到父节点的位置                    //如果是上下左右位置的则g等于10，斜对角的就是14                    var g = currentPoint.G + ((currentPoint.x - item.x) * (currentPoint.y - item.y) == 0 ? 10 : 14);                    if (!existList(item, openList)) {       //如果不在开启列表中                        //计算H，通过水平和垂直距离进行确定                        item['H'] = Math.abs(end_x - item.x) * 10 + Math.abs(end_y - item.y) * 10;                        item['G'] = g;                        item['F'] = item.H + item.G;                        item['parent'] = currentPoint;                        openList.push(item);                    }                    //存在在开启列表中，比较目前的g值和之前的g的大小                    else                    {                        var index = existList(item, openList);                        //如果当前点的g更小                        if (g < openList[index].G)                        {                            openList[index].parent = currentPoint;                            openList[index].G = g;                            openList[index].F=g+openList[index].H;                        }                    }                }            }            //如果开启列表空了，没有通路，结果为空            if(openList.length == 0)            {                break;            }            //这一步是为了循环回去的时候，找出 F 值最小的, 将它从 "开启列表" 中移掉            openList.sort(sortF);        }while(!(result_index=existList({x:end_x,y:end_y},openList)));        //判断结果列表是否为空        if(!result_index)        {            result = [];        }        else        {            var currentObj=openList[result_index];            do{                //把路劲节点添加到result当中                result.unshift({                    x:currentObj.x,                    y:currentObj.y                });                currentObj=currentObj.parent;            }while (currentObj.x != start_x || currentObj.y != start_y);        }        return result;    },});var HelloWorldScene = cc.Scene.extend({    onEnter:function () {        this._super();        var layer = new HelloWorldLayer();        this.addChild(layer);    }});

1 0