项目下载
https://download.csdn.net/download/K86338236/89529461

根据多边形碰撞体范围划定障碍范围，躲避障碍，点击屏幕移动，每次点击更新寻路路径 移动用tween实现

const { ccclass, property } = cc._decorator;

@ccclass
export default class AStar extends cc.Component {
    @property(cc.Graphics)
    map: cc.Graphics = null;
    @property(cc.Node)
    item: cc.Node = null;
    @property(cc.Node)
    itemBlockRoot: cc.Node = null;

    _gridW = 50;   // 单元格子宽度
    _gridH = 50;   // 单元格子高度
    mapH = 13;     // 纵向格子数量
    mapW = 25;     // 横向格子数量

    is8dir = true; // 是否8方向寻路

    gridsList = null

    onLoad() {
        const manager = cc.director.getCollisionManager();
        manager.enabled = true;
        manager.enabledDebugDraw = true;
        manager.enabledDrawBoundingBox = true;

        this.mapH = Math.round(cc.winSize.height / this._gridH);
        this.mapW = Math.round(cc.winSize.width / this._gridW);
        this.initMap();
        this.initBlock()
        this.node.on(cc.Node.EventType.TOUCH_START, this.onTouchMove, this);
        this.node.on(cc.Node.EventType.TOUCH_MOVE, this.onTouchMove, this);
        this.node.on(cc.Node.EventType.TOUCH_END, this.onTouchEnd, this);
        this.node.on(cc.Node.EventType.TOUCH_CANCEL, this.onTouchEnd, this);
    }

    initBlock() {
        this.itemBlockRoot.children.forEach((value) => {
            let collider = value.getComponent(cc.PolygonCollider)
            if (!collider) return
            let points = collider.points;

            for (let col = 0; col <= this.mapW; col++) {
                for (let row = 0; row <= this.mapH; row++) {
                    let oPos = this.getPos(cc.v2(col + 0.5, row + 0.5))
                    let w_pos = this.node.convertToWorldSpaceAR(oPos);
                    let pos = value.convertToNodeSpaceAR(w_pos);
                    let isIn = cc.Intersection.pointInPolygon(cc.v2(pos), points)
                    if (isIn) {
                        this.addBlock(cc.v2(col, row))
                    }
                }
            }
        })
        this.drawBlock()
    }

    initMap() {
        // 初始化格子二维数组
        this.gridsList = new Array(this.mapW + 1);
        for (let col = 0; col < this.gridsList.length; col++) {
            this.gridsList[col] = new Array(this.mapH + 1);
        }

        this.map.clear();
        for (let col = 0; col <= this.mapW; col++) {
            for (let row = 0; row <= this.mapH; row++) {
                this.addGrid(col, row, 0);
            }
        }
    }

    drawBlock() {
        for (let col = 0; col <= this.mapW + 1; col++) {
            this.drawLine(cc.v2(col, 0), cc.v2(col, this.mapH + 1));
        }
        for (let row = 0; row <= this.mapH + 1; row++) {
            this.drawLine(cc.v2(0, row), cc.v2(this.mapW + 1, row));
        }
        for (let col = 0; col <= this.mapW; col++) {
            for (let row = 0; row <= this.mapH; row++) {
                if (this.gridsList[col][row].type == -1) {
                    this.draw(col, row, cc.Color.RED);
                }
            }
        }
    }

    addBlock(newPos) {
        const { x, y } = newPos;
        if (!this.gridsList[x] || !this.gridsList[x][y]) return
        if (this.gridsList[x][y].type == 0) {
            this.gridsList[x][y].type = -1;
        }
    }

    onTouchMove(event) {
        return
        let oPos = event.getLocation();
        let pos = this.map.node.convertToNodeSpaceAR(oPos)
        let newPos = this.getColRow(pos)
        const { x, y } = newPos;
        if (!this.gridsList[x] || !this.gridsList[x][y]) return
        if (this.gridsList[x][y].type == 0) {
            this.gridsList[x][y].type = -1;
            this.draw(x, y, cc.Color.RED);
        }
        cc.log(x + "," + y);
    }

    onTouchEnd(event) {
        this.map.clear();
        this.drawBlock()
        this.item.stopAllActions();
        let oPos = event.getLocation();
        let touchPos = this.map.node.convertToNodeSpaceAR(oPos)
        let lastPos = this.item.position;
        let startpos = this.getColRow(lastPos)
        let endpos = this.getColRow(touchPos)
        this.draw(startpos.x, startpos.y, cc.Color.YELLOW);
        this.draw(endpos.x, endpos.y, cc.Color.GREEN);
        // 开始寻路
        let path = this.findPath(startpos, endpos);
        if (!path) return
        let tween = cc.tween(this.item)
        let speed = 300;
        for (let i = path.length - 2; i >= 0; i--) {
            const element = path[i];
            let pos = this.getPos(cc.v2(element.x + 0.5, element.y + 0.5))
            let dis = lastPos.sub(pos).mag()
            let t = dis / speed;
            let tween2 = cc.tween().to(t, { position: pos })
            tween.then(tween2)
            lastPos = pos;
        }
        tween.start()
    }

    addGrid(x, y, type) {
        let grid = {
            x: 0,
            y: 0,
            f: 0,
            g: 0,
            h: 0,
            parent: null,
            type: 0 // -1障碍物， 0正常， 1起点， 2目的点
        }
        grid.x = x;
        grid.y = y;
        grid.type = type;
        this.gridsList[x][y] = grid;
    }

    _sortFunc(x, y) {
        return x.f - y.f;
    }

    generatePath(grid) {
        let path = []
        path.push(grid);
        while (grid.parent) {
            grid = grid.parent;
            path.push(grid);
        }
        cc.log("path.length: " + path.length);
        for (let i = 0; i < path.length; i++) {
            // 起点终点不覆盖，方便看效果
            if (i != 0 && i != path.length - 1) {
                let grid = path[i];
                this.draw(grid.x, grid.y, cc.Color.GREEN);
            }
        }
        return path;
    }

    findPath(startPos, endPos) {
        let openList = [];
        let closeList = [];
        let gridsList = JSON.parse(JSON.stringify(this.gridsList))

        let startGrid = gridsList[startPos.x][startPos.y];
        let endGrid = gridsList[endPos.x][endPos.y];
        endGrid.type = 2;

        openList.push(startGrid);
        let curGrid = openList[0];
        while (openList.length > 0 && curGrid.type != 2) {
            // 每次都取出f值最小的节点进行查找
            curGrid = openList[0];
            if (curGrid.type == 2) {
                cc.log("find path success.");
                endGrid.type = 0;
                return this.generatePath(curGrid);
            }

            for (let i = -1; i <= 1; i++) {
                for (let j = -1; j <= 1; j++) {
                    if (i != 0 || j != 0) {
                        let col = curGrid.x + i;
                        let row = curGrid.y + j;
                        if (col >= 0 && row >= 0 && col <= this.mapW && row <= this.mapH
                            && gridsList[col][row].type != -1
                            && closeList.indexOf(gridsList[col][row]) < 0) {
                            if (this.is8dir) {
                                // 8方向 斜向走动时要考虑相邻的是不是障碍物
                                if (gridsList[col - i][row].type == -1 || gridsList[col][row - j].type == -1) {
                                    continue;
                                }
                            } else {
                                // 四方形行走
                                if (Math.abs(i) == Math.abs(j)) {
                                    continue;
                                }
                            }

                            // 计算g值
                            let g = curGrid.g + Math.sqrt(Math.pow(i * 10, 2) + Math.pow(j * 10, 2));
                            if (gridsList[col][row].g == 0 || gridsList[col][row].g > g) {
                                gridsList[col][row].g = g;
                                // 更新父节点
                                gridsList[col][row].parent = curGrid;
                            }
                            // 计算h值 manhattan估算法
                            gridsList[col][row].h = Math.abs(endPos.x - col) + Math.abs(endPos.y - row);
                            // 更新f值
                            gridsList[col][row].f = gridsList[col][row].g + gridsList[col][row].h;
                            // 如果不在开放列表里则添加到开放列表里
                            if (openList.indexOf(gridsList[col][row]) < 0) {
                                openList.push(gridsList[col][row]);
                            }
                            // // 重新按照f值排序（升序排列)
                            // openList.sort(this._sortFunc);
                        }
                    }
                }
            }
            // 遍历完四周节点后把当前节点加入关闭列表
            closeList.push(curGrid);
            // 从开放列表把当前节点移除
            openList.splice(openList.indexOf(curGrid), 1);
            if (openList.length <= 0) {
                cc.log("find path failed.");
            }

            // 重新按照f值排序（升序排列)
            openList.sort(this._sortFunc);
        }
        return false;
    }

    getPos(pos) {
        const { x, y } = pos
        let posX = (x - this.mapW / 2) * (this._gridW);
        let posY = (y - this.mapH / 2) * (this._gridH);
        return cc.v3(posX, posY)
    }

    getColRow(pos) {
        let x = Math.floor(pos.x / (this._gridW) + this.mapW / 2);
        let y = Math.floor(pos.y / (this._gridH) + this.mapH / 2);
        return cc.v3(x, y)
    }

    drawLine(start_col_cow, end_col_cow, color = cc.Color.GRAY, width = 4) {
        this.map.strokeColor = color;
        this.map.strokeColor.a = 10;//添加透明度
        let pos1 = this.getPos(start_col_cow)
        let pos2 = this.getPos(end_col_cow)
        this.map.lineWidth = width;
        this.map.moveTo(pos1.x, pos1.y);
        this.map.lineTo(pos2.x, pos2.y);
        this.map.stroke();
    }
    draw(col, row, color = new cc.Color().fromHEX("#FF000033")) {
        this.map.fillColor = color;
        this.map.fillColor.a = 20;//添加透明度
        let pos = this.getPos(cc.v2(col, row))
        this.map.fillRect(pos.x, pos.y, this._gridW, this._gridH);
    }

}