这篇文章主要介绍了基于javascript实现获取最短路径算法代码实例,文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下

代码如下

//A算法 自动寻路 路径

class GetAutoPath{

constructor(id, map, sPos, ePos, mapArr){

//this.type = id.type;

this.id = id;

this.map = map;

this.sPos = sPos;

this.ePos = ePos;

this.mapArr = mapArr;

this.maxMach = 10000;

this.openArr = [];

this.closeArr = [];

this.minPath = [];

if(!this.isPath(this.sPos.x, this.sPos.y)){this.sPos = this.getNewDot(sPos, ePos);}

if(!this.isPath(this.ePos.x, this.ePos.y)){this.ePos = this.getNewDot(ePos, sPos);}

//console.log(this.mapArr);

return this.run();

}

posts(txt, arr){//post消息

//let id = this.id, sPos = this.sPos, ePos = this.ePos, arrs = arr || [];

return {id:this.id, map:this.map, arr:arr || [], sPos:this.sPos, ePos:this.ePos, txt:txt}

}

isPath(x, y){//isPath = true 合法路径 = isBanPath === undefined

let isPath = false, ym = this.mapArr.get(y), xm; //console.log(ym); debugger;

if(ym !== undefined){

xm = ym.get(x);

if(xm !== undefined){

if(xm.isBanPath === undefined){isPath = true;}

}

}

//if(this.mapArr[y] !== undefined && this.mapArr[y][x] !== undefined && this.mapArr[y][x].isPath === 1){isPath = true;}

return isPath;

}

getEqual(arr, x, y){//获取目标数组相同的坐标

let isPos = false;

if(arr.length === 0){

isPos = false;

}else{

isPos = arr.some(function (o){return o.x === x && o.y === y;});

}

return isPos;

}

getDot(x, y){//获取周围8个方向坐标

return [{x:x-1,y:y},{x:x+1,y:y},{x:x,y:y-1},{x:x,y:y+1},{x:x-1,y:y-1},{x:x+1,y:y+1},{x:x+1,y:y-1},{x:x-1,y:y+1}]

}

getNewDot(setPos, pos){//重定义起点或终点

let dot = setPos, pointDot, k, arr = [], arrs = [], g, end, maxMachT = 0;

while(!end && maxMachT < this.maxMach){

maxMachT++;

pointDot = this.getDot(dot.x, dot.y);

for(k in pointDot){

g = Math.round(Math.sqrt(Math.abs(pointDot[k].x - pos.x) + Math.abs(pointDot[k].y - pos.y)) * 100) / 100;

if(!this.isPath(pointDot[k].x, pointDot[k].y)){//不合法

arr.push({x:pointDot[k].x, y:pointDot[k].y, g:g});

arr.sort(function(a, b){return a.g - b.g;});

}else{//合法

arrs.push({x:pointDot[k].x, y:pointDot[k].y, g:g});

arrs.sort(function(a, b){return a.g - b.g;});

}

if(arrs.length > 0){end = true;}

}

dot = {x:arr[0].x, y:arr[0].y, g:arr[0].g}; arr = [];

}

if(!arrs[0].x || !arrs[0].y){return this.posts("没有符合的坐标");}

return {x:arrs[0].x, y:arrs[0].y};

}

run(){

if(this.sPos.x === undefined || this.ePos.x === undefined){return this.posts("没有符合的坐标");}

let sPos = this.sPos, ePos = this.ePos, point, key, i, newPoint, ger, gers, g, h, f, maxMachT = 0;

this.openArr[0] = {x : sPos.x, y : sPos.y, f : 0, p : 0, ger : 0}

while(this.openArr.length > 0){

maxMachT++;

point = this.openArr[0]; this.closeArr.push(point); this.openArr.splice(0,1);

key = this.closeArr.length - 1;//设置当前节点

newPoint = this.getDot(point.x, point.y);//获取周围点

for(i in newPoint){//设置周围点

ger = Math.round(Math.sqrt(Math.abs(newPoint[i].x - point.x) + Math.abs(newPoint[i].y - point.y)) * 100) / 100;//到当前节点的曼哈顿距离,保留两位小数点

gers = ger + point.ger;

g = Math.round(gers * 100) / 100;

h = Math.abs(newPoint[i].x - ePos.x) + Math.abs(newPoint[i].y - ePos.y);

f = g + h;

if(this.isPath(newPoint[i].x, newPoint[i].y) && !this.getEqual(this.openArr, newPoint[i].x, newPoint[i].y) && !this.getEqual(this.closeArr, newPoint[i].x, newPoint[i].y)){this.openArr.push({x:newPoint[i].x, y:newPoint[i].y, f:f, p:key, ger:ger});}

}

this.openArr.sort(function(a, b){return a.f - b.f;});//排序

if(this.getEqual(this.closeArr, ePos.x, ePos.y) || this.getEqual(this.openArr, ePos.x, ePos.y)){//end

this.minPath.unshift(this.closeArr[key]);

while(this.minPath.length > 0){

if(this.minPath[0].p == 0){return this.posts('success', this.minPath);}else{this.minPath.unshift(this.closeArr[this.minPath[0].p]);}

}

}else if(maxMachT === this.maxMach){

return this.posts("没有符合的坐标");

}

}

return this.posts("没有符合的坐标");

}

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。