A*寻路算法，DEMO展示A*（A星）寻路算法讲解在DEMO展示中，有三个版本，由于代码写了很久了，我也不记得下面贴出的代码是哪个版本的了，见谅。。
首先是文档类Index.as：
package code{
import flash.display.Sprite;
import flash.text.TextField;
import flash.text.TextFormat;
public class Index extends Sprite{
private var road:Road;
public function Index(){
stage.align = "TL";
stage.scaleMode = "noScale";
stage.showDefaultContextMenu = false;
init();
}
//初始化
private function init():void{
road = new Road;
addChild(road);
road.x = GV.ROAD_INIT_X;
road.y = GV.ROAD_INIT_Y;
//地图规格申明
var text:TextField = new TextField;
text.htmlText = "地图规格：50*50方格，障碍物500方格 寻路算法：A*（星） 制作：sunbright";
addChild(text);
text.x = 25;
text.y = 530;
text.width = 500;
text.selectable = false;
text.mouseEnabled = false;
text.setTextFormat(new TextFormat("宋体",12,0xffffff));
text = null;
}
}
}
定义参数的类：GV.as
package{
public class GV{
public function GV(){
throw new Error("变量");
}
//Road创建的初始x、y坐标
public static const ROAD_INIT_X:int = 25;
public static const ROAD_INIT_Y:int = 25;
//纵横方块参数
public static const WIDTH_NUMBER:int = 50;
public static const HEIGHT_NUMBER:int = 50;
public static const WIDTH_TOTAL:int = 500;
public static const HEIGHT_TOTAL:int = 500;
public static const GRID_WIDTH:int = 10;
public static const GRID_HEIGHT:int = 10;
//障碍物个数
public static const THING_NUMBER:int = 500;
//state状态参数表示
public static const HAVE_THING:int = 1;
public static const IMPASSE_VALUE:int = 2;
public static const MAIN_VALUE:int = 8;
//路径耗费固定值
public static const BIAS_VALUE:int = 14;
public static const LINE_VALUE:int = 10;
//文本表示
public static const IMPASSE:String = "死路！";
public static const RESULT_FRONT:String = "用时 ";
public static const RESULT_BACK:String = " 毫秒";
}
}
主要算法所存在的Road.as类
package code{
import flash.display.Sprite;
import flash.events.MouseEvent;
import flash.text.TextField;
import flash.text.TextFormat;
import flash.utils.clearInterval;
import flash.utils.getTimer;
import flash.utils.setInterval;
public class Road extends Sprite{
private var lands:Sprite;
private var things:Sprite;
private var c:Coordinate;
private var main:Main;
private var click:Sprite;
private var drawPath:Sprite;
private var result:TextField;
private var unlockList:Array;
private var lockList:Object;
private var targetIX:int;
private var targetIY:int;
private var intervalID:int = 0;
private var startTime:int;
private var endTime:int;
public function Road(){
init();
}
//初始化
private function init():void{
//创建坐标
c = new Coordinate;
//创建文本框
result = new TextField;
result.mouseEnabled = false;
result.autoSize = "left";
result.y = -20;
result.selectable = false;
result.defaultTextFormat = new TextFormat("宋体",12,0xffffff);
addChild(result);
result.text = "结果";
//创建平原
lands = new Sprite;
lands.mouseChildren = false;
lands.mouseEnabled = false;
addChild(lands);
lands.graphics.beginFill(0xff0000);
lands.graphics.lineStyle(0);
lands.graphics.drawRect(0,0,GV.WIDTH_TOTAL,GV.HEIGHT_TOTAL);
for(var i:int = 1; i < GV.WIDTH_NUMBER; i ++){
lands.graphics.moveTo(GV.GRID_WIDTH * i,0);
lands.graphics.lineTo(GV.GRID_WIDTH * i,GV.HEIGHT_TOTAL);
lands.graphics.endFill();
lands.graphics.moveTo(0,GV.GRID_HEIGHT * i);
lands.graphics.lineTo(GV.WIDTH_TOTAL,GV.GRID_HEIGHT * i);
lands.graphics.endFill();
}
//创建障碍层
things = new Sprite;
things.mouseChildren = false;
things.mouseEnabled = false;
addChild(things);
//创建路线绘制层
drawPath = new Sprite;
addChild(drawPath);
//创建操控人
main = new Main;
addChild(main);
//创建控制区
click = new Sprite;
click.graphics.beginFill(0,0);
click.graphics.drawRect(0,0,GV.WIDTH_TOTAL,GV.HEIGHT_TOTAL);
addChild(click);
click.addEventListener(MouseEvent.CLICK,clickHandle);
//开始初始化
randomState();
createRoad();
}
//随机生成障碍
private function randomState():void{
var ix:int;
var iy:int;
var i:int = 0;
//随机障碍
while(i < GV.THING_NUMBER){
ix = int(Math.random() * GV.WIDTH_NUMBER);
iy = int(Math.random() * GV.HEIGHT_NUMBER);
if(c[ix][iy] == null){
i ++;
c[ix][iy] = GV.HAVE_THING;
}
}
//随机摆放操控人
while(true){
ix = int(Math.random() * GV.WIDTH_NUMBER);
iy = int(Math.random() * GV.HEIGHT_NUMBER);
if(c[ix][iy] == null){
c[ix][iy] = GV.MAIN_VALUE;
break;
}
}
}
//创建马路现状
private function createRoad():void{
for(var i:int = 0; i < GV.WIDTH_NUMBER * GV.HEIGHT_NUMBER; i ++){
var state:State = new State;
var ix:int = i % GV.WIDTH_NUMBER;
var iy:int = Math.floor(i / GV.HEIGHT_NUMBER);
state.value = c[ix][iy];
switch(state.value){
case GV.HAVE_THING://如果等于1表示有障碍
var thing:Thing = new Thing;
thing.x = ix * GV.GRID_WIDTH;
thing.y = iy * GV.GRID_HEIGHT;
things.addChild(thing);
thing = null;
break;
case GV.IMPASSE_VALUE://如多等于2表示死路
//死路只需将value设置成2即可！
break;
case GV.MAIN_VALUE://如果等于8表示操控人
main.x = ix * GV.GRID_WIDTH;
main.y = iy * GV.GRID_HEIGHT;
break;
}
c[ix][iy] = state;
}
}
//点击触发
private function clickHandle(e:MouseEvent):void{
drawPath.graphics.clear();
targetIX = Math.floor(e.localX / GV.GRID_WIDTH);
targetIY = Math.floor(e.localY / GV.GRID_HEIGHT);
//时间记录
startTime = getTimer();
var path:Array = seekRoad();
endTime = getTimer();
//根据路径开始走路
walkRoad(path);
path = null;
}
//开始走路
private function walkRoad(path:Array):void{
//显示寻路消耗时间
result.text = GV.RESULT_FRONT + (endTime - startTime) + GV.RESULT_BACK;
//判断是否为死路
if(path.length == 0){
result.text = GV.IMPASSE + result.text;
}
drawPath.graphics.lineStyle(2,0xffffff);
path.just = true;
intervalID = setInterval(walkRoadHandle,50,path);
}
//走路处理
private function walkRoadHandle(path:Array):void{
//是否路已经走完
if(path.length == 0){
//结束走路
clearInterval(intervalID);
//开启触发器
click.mouseEnabled = true;
return;
}
//开始走路
var obj:Object = path.shift();
main.x = obj.x;
main.y = obj.y;
obj = null;
//绘制路径
if(path.just){
path.just = false;
drawPath.graphics.moveTo(main.x + 5,main.y + 5);
}else{
drawPath.graphics.lineTo(main.x + 5,main.y + 5);
}
}
//开始寻路
private function seekRoad():Array{
//关闭触发器
click.mouseEnabled = false;
//判断目标点是不是有障碍，或者是不是死路
if(c[targetIX][targetIY].isThing || c[targetIX][targetIY].isWalk){
return new Array;
}
//寻路初始化
var path:Array = new Array;
unlockList = new Array;
lockList = new Object;
//初始标记
var ix:int = main.ix;
var iy:int = main.iy;
//创建开始标记
var sign:Sign = new Sign(ix,iy,0,0,null);
lockList[ix + "_" + iy] = sign;
while(true){
//生成八个方向的标记开启
addUnlockList(createSign(ix + 1,iy - 1,true ,sign));
addUnlockList(createSign(ix + 1,iy ,false,sign));
addUnlockList(createSign(ix + 1,iy + 1,true ,sign));
addUnlockList(createSign(ix - 1,iy + 1,true ,sign));
addUnlockList(createSign(ix ,iy + 1,false,sign));
addUnlockList(createSign(ix - 1,iy ,false,sign));
addUnlockList(createSign(ix - 1,iy - 1,true ,sign));
addUnlockList(createSign(ix ,iy - 1,false,sign));
//判断开启列表是否已经为空
if(unlockList.length == 0){
break;
}
//从开启列表中取出h值最低的标记
unlockList.sortOn("f",Array.NUMERIC);
sign = unlockList.shift();
lockList[sign.ix + "_" + sign.iy] = sign;
ix = sign.ix;
iy = sign.iy;
//判断是否找出路径
if(ix == targetIX && iy == targetIY){
while(sign != null){
path.push(sign.getSign());
sign = sign.p;
}
break;
}
}
sign = null;
return path.reverse();
}
//添加到开启标记列表
private function addUnlockList(sign:Sign):void{
if(sign){
unlockList.push(sign);
unlockList[sign.ix + "_" + sign.iy] = sign;
}
}
//生成标记
private function createSign(ix:int,iy:int,p:Boolean,_p:Sign):Sign{
//是否出格
if(ix < 0 || iy < 0 || ix >= GV.WIDTH_NUMBER || iy >= GV.HEIGHT_NUMBER){
return null;
}
//是否有障碍物
if(c[ix][iy].isThing){
return null;
}
//是否已经加入关闭标记列表
if(lockList[ix + "_" + iy]){
return null;
}
//是否已经加入开启标记列表
if(unlockList[ix + "_" + iy]){
return null;
}
//判断当斜着走的时候，它的上下或者左右是否有障碍物
if(p){
if(c[_p.ix][iy].isThing || c[ix][_p.iy].isThing){
return null;
}
}
var cx:Number = Math.abs(targetIX - ix);
var cy:Number = Math.abs(targetIY - iy);
return new Sign(ix,iy,
p ? GV.BIAS_VALUE : GV.LINE_VALUE,
(cx + cy) * 10,
_p);
}
}
}
标记数据记录，Sign.as类
package code{
public class Sign{
private var _ix:Number;
private var _iy:Number;
private var _p:Sign;
private var _f:int = 0;
private var _g:int = 0;
private var _h:int = 0;
//f表示路径评分、g表示当前移动耗费、h表示当前估计移动耗费
//公式：f = g + h，表示路径评分的算法
//ng值表示以父标记为主标记的g值
//nh值表示当前估计移动耗费
public function Sign(_ix:Number,_iy:Number,ng:int,nh:int,_p:Sign = null){
this._ix = _ix;
this._iy = _iy;
this._p = _p;
if(_p){
_g = _p.g + ng;
_h = nh;
_f = _g + _h;
}
}
//获取该标记的坐标
public function getSign():Object{
return {x:_ix * GV.GRID_WIDTH,y:_iy * GV.GRID_HEIGHT};
}
//获取它表示的x坐标
public function get ix():int{
return _ix;
}
//获取它表示的y坐标
public function get iy():int{
return _iy;
}
//获取父标记
public function get p():Sign{
return _p;
}
//获取路径评分
public function get f():int{
return _f;
}
//获取当前路径移动耗费
public function get g():int{
return _g;
}
//获取当前路径耗费估值
public function get h():int{
return _h;
}
//重写toString值
public function toString():String{
return ix + "," + iy;
}
}
}
某点状态类，State.as
package code{
public class State{
public var value:int = 0;
public function State(){
}
//获取是否障碍
public function get isThing():Boolean{
return value == GV.HAVE_THING;
}
//获取是否死路
public function get isWalk():Boolean{
return value == GV.IMPASSE_VALUE;
}
//重写toString
public function toString():String{
return value.toString();
}
}
}
物体类：Thing.as
package code{
import flash.display.Sprite;
public class Thing extends Sprite{
public function Thing(){
init();
}
//初始化
private function init():void{
graphics.beginFill(0);
graphics.drawRect(0,0,GV.GRID_WIDTH,GV.GRID_HEIGHT);
mouseEnabled = false;
mouseChildren = false;
}
}
}
坐标系类，Coordinate.as
package code{
public dynamic class Coordinate extends Array{
public function Coordinate(){
init();
}
//初始化
private function init():void{
for(var i:int = 0; i < GV.WIDTH_NUMBER; i ++){
push(new Array(GV.HEIGHT_NUMBER));
}
}
}
}
主角类，Main.as
package code{
import flash.display.Sprite;
public class Main extends Sprite{
public function Main(){
init();
}
//初始化
private function init():void{
graphics.beginFill(0x0000ff);
graphics.drawRect(0,0,GV.GRID_WIDTH,GV.GRID_HEIGHT);
mouseEnabled = false;
mouseChildren = false;
}
//获取ix坐标
public function get ix():int{
return int(x / GV.GRID_WIDTH);
}
//获取iy坐标
public function get iy():int{
return int(y / GV.GRID_HEIGHT);
}
}
}
源文件打包下载下载源文件，直接打开move.fla运行即可
