新增a*寻路

This commit is contained in:
yhh
2020-06-09 19:45:09 +08:00
parent 9e0d14da7c
commit 0fd33be5f9
14 changed files with 998 additions and 3 deletions

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@@ -17,6 +17,61 @@ declare interface Array<T> {
groupBy(keySelector: Function): Array<T>; groupBy(keySelector: Function): Array<T>;
sum(selector: any): any; sum(selector: any): any;
} }
declare class PriorityQueueNode {
priority: number;
insertionIndex: number;
queueIndex: number;
}
declare class AStarPathfinder {
static search<T>(graph: IAstarGraph<T>, start: T, goal: T): T[];
private static hasKey;
private static getKey;
static recontructPath<T>(cameFrom: Map<T, T>, start: T, goal: T): T[];
}
declare class AStarNode<T> extends PriorityQueueNode {
data: T;
constructor(data: T);
}
declare class AstarGridGraph implements IAstarGraph<Point> {
dirs: Point[];
walls: Point[];
weightedNodes: Point[];
defaultWeight: number;
weightedNodeWeight: number;
private _width;
private _height;
private _neighbors;
constructor(width: number, height: number);
isNodeInBounds(node: Point): boolean;
isNodePassable(node: Point): boolean;
search(start: Point, goal: Point): Point[];
getNeighbors(node: Point): Point[];
cost(from: Point, to: Point): number;
heuristic(node: Point, goal: Point): number;
}
interface IAstarGraph<T> {
getNeighbors(node: T): Array<T>;
cost(from: T, to: T): number;
heuristic(node: T, goal: T): any;
}
declare class PriorityQueue<T extends PriorityQueueNode> {
private _numNodes;
private _nodes;
private _numNodesEverEnqueued;
constructor(maxNodes: number);
clear(): void;
readonly count: number;
contains(node: T): boolean;
enqueue(node: T, priority: number): void;
dequeue(): T;
remove(node: T): void;
isValidQueue(): boolean;
private onNodeUpdated;
private cascadeDown;
private cascadeUp;
private swap;
private hasHigherPriority;
}
declare abstract class Component { declare abstract class Component {
entity: Entity; entity: Entity;
displayRender: egret.DisplayObject; displayRender: egret.DisplayObject;
@@ -338,6 +393,11 @@ declare class Matrix2D {
static createRotation(radians: number, result?: Matrix2D): Matrix2D; static createRotation(radians: number, result?: Matrix2D): Matrix2D;
static createScale(xScale: number, yScale: number, result?: Matrix2D): Matrix2D; static createScale(xScale: number, yScale: number, result?: Matrix2D): Matrix2D;
} }
declare class Point {
x: number;
y: number;
constructor(x: number, y: number);
}
declare class Vector2 { declare class Vector2 {
x: number; x: number;
y: number; y: number;

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@@ -238,6 +238,262 @@ Array.prototype.sum = function (selector) {
} }
return sum(this, selector); return sum(this, selector);
}; };
var PriorityQueueNode = (function () {
function PriorityQueueNode() {
this.priority = 0;
this.insertionIndex = 0;
this.queueIndex = 0;
}
return PriorityQueueNode;
}());
var AStarPathfinder = (function () {
function AStarPathfinder() {
}
AStarPathfinder.search = function (graph, start, goal) {
var _this = this;
var foundPath = false;
var cameFrom = new Map();
cameFrom.set(start, start);
var costSoFar = new Map();
var frontier = new PriorityQueue(1000);
frontier.enqueue(new AStarNode(start), 0);
costSoFar.set(start, 0);
var _loop_2 = function () {
var current = frontier.dequeue();
if (JSON.stringify(current.data) == JSON.stringify(goal)) {
foundPath = true;
return "break";
}
graph.getNeighbors(current.data).forEach(function (next) {
var newCost = costSoFar.get(current.data) + graph.cost(current.data, next);
if (!_this.hasKey(costSoFar, next) || newCost < costSoFar.get(next)) {
costSoFar.set(next, newCost);
var priority = newCost + graph.heuristic(next, goal);
frontier.enqueue(new AStarNode(next), priority);
cameFrom.set(next, current.data);
}
});
};
while (frontier.count > 0) {
var state_1 = _loop_2();
if (state_1 === "break")
break;
}
return foundPath ? this.recontructPath(cameFrom, start, goal) : null;
};
AStarPathfinder.hasKey = function (map, compareKey) {
var iterator = map.keys();
var r;
while (r = iterator.next(), !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return true;
}
return false;
};
AStarPathfinder.getKey = function (map, compareKey) {
var iterator = map.keys();
var valueIterator = map.values();
var r;
var v;
while (r = iterator.next(), v = valueIterator.next(), !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return v.value;
}
return null;
};
AStarPathfinder.recontructPath = function (cameFrom, start, goal) {
var path = [];
var current = goal;
path.push(goal);
while (current != start) {
current = this.getKey(cameFrom, current);
path.push(current);
}
path.reverse();
return path;
};
return AStarPathfinder;
}());
var AStarNode = (function (_super) {
__extends(AStarNode, _super);
function AStarNode(data) {
var _this = _super.call(this) || this;
_this.data = data;
return _this;
}
return AStarNode;
}(PriorityQueueNode));
var AstarGridGraph = (function () {
function AstarGridGraph(width, height) {
this.dirs = [
new Point(1, 0),
new Point(0, -1),
new Point(-1, 0),
new Point(0, 1)
];
this.walls = [];
this.weightedNodes = [];
this.defaultWeight = 1;
this.weightedNodeWeight = 5;
this._neighbors = new Array(4);
this._width = width;
this._height = height;
}
AstarGridGraph.prototype.isNodeInBounds = function (node) {
return 0 <= node.x && node.x < this._width && 0 <= node.y && node.y < this._height;
};
AstarGridGraph.prototype.isNodePassable = function (node) {
return !this.walls.contains(node);
};
AstarGridGraph.prototype.search = function (start, goal) {
return AStarPathfinder.search(this, start, goal);
};
AstarGridGraph.prototype.getNeighbors = function (node) {
var _this = this;
this._neighbors.length = 0;
this.dirs.forEach(function (dir) {
var next = new Point(node.x + dir.x, node.y + dir.y);
if (_this.isNodeInBounds(next) && _this.isNodePassable(next))
_this._neighbors.push(next);
});
return this._neighbors;
};
AstarGridGraph.prototype.cost = function (from, to) {
return this.weightedNodes.find(function (p) { return JSON.stringify(p) == JSON.stringify(to); }) ? this.weightedNodeWeight : this.defaultWeight;
};
AstarGridGraph.prototype.heuristic = function (node, goal) {
return Math.abs(node.x - goal.x) + Math.abs(node.y - goal.y);
};
return AstarGridGraph;
}());
var PriorityQueue = (function () {
function PriorityQueue(maxNodes) {
this._numNodes = 0;
this._nodes = new Array(maxNodes + 1);
this._numNodesEverEnqueued = 0;
}
PriorityQueue.prototype.clear = function () {
this._nodes.splice(1, this._numNodes);
this._numNodes = 0;
};
Object.defineProperty(PriorityQueue.prototype, "count", {
get: function () {
return this._numNodes;
},
enumerable: true,
configurable: true
});
PriorityQueue.prototype.contains = function (node) {
return (this._nodes[node.queueIndex] == node);
};
PriorityQueue.prototype.enqueue = function (node, priority) {
node.priority = priority;
this._numNodes++;
this._nodes[this._numNodes] = node;
node.queueIndex = this._numNodes;
node.insertionIndex = this._numNodesEverEnqueued++;
this.cascadeUp(this._nodes[this._numNodes]);
};
PriorityQueue.prototype.dequeue = function () {
var returnMe = this._nodes[1];
this.remove(returnMe);
return returnMe;
};
PriorityQueue.prototype.remove = function (node) {
if (node.queueIndex == this._numNodes) {
this._nodes[this._numNodes] = null;
this._numNodes--;
return;
}
var formerLastNode = this._nodes[this._numNodes];
this.swap(node, formerLastNode);
delete this._nodes[this._numNodes];
this._numNodes--;
this.onNodeUpdated(formerLastNode);
};
PriorityQueue.prototype.isValidQueue = function () {
for (var i = 1; i < this._nodes.length; i++) {
if (this._nodes[i]) {
var childLeftIndex = 2 * i;
if (childLeftIndex < this._nodes.length && this._nodes[childLeftIndex] &&
this.hasHigherPriority(this._nodes[childLeftIndex], this._nodes[i]))
return false;
var childRightIndex = childLeftIndex + 1;
if (childRightIndex < this._nodes.length && this._nodes[childRightIndex] &&
this.hasHigherPriority(this._nodes[childRightIndex], this._nodes[i]))
return false;
}
}
return true;
};
PriorityQueue.prototype.onNodeUpdated = function (node) {
var parentIndex = Math.floor(node.queueIndex / 2);
var parentNode = this._nodes[parentIndex];
if (parentIndex > 0 && this.hasHigherPriority(node, parentNode)) {
this.cascadeUp(node);
}
else {
this.cascadeDown(node);
}
};
PriorityQueue.prototype.cascadeDown = function (node) {
var newParent;
var finalQueueIndex = node.queueIndex;
while (true) {
newParent = node;
var childLeftIndex = 2 * finalQueueIndex;
if (childLeftIndex > this._numNodes) {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
var childLeft = this._nodes[childLeftIndex];
if (this.hasHigherPriority(childLeft, newParent)) {
newParent = childLeft;
}
var childRightIndex = childLeftIndex + 1;
if (childRightIndex <= this._numNodes) {
var childRight = this._nodes[childRightIndex];
if (this.hasHigherPriority(childRight, newParent)) {
newParent = childRight;
}
}
if (newParent != node) {
this._nodes[finalQueueIndex] = newParent;
var temp = newParent.queueIndex;
newParent.queueIndex = finalQueueIndex;
finalQueueIndex = temp;
}
else {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
}
};
PriorityQueue.prototype.cascadeUp = function (node) {
var parent = Math.floor(node.queueIndex / 2);
while (parent >= 1) {
var parentNode = this._nodes[parent];
if (this.hasHigherPriority(parentNode, node))
break;
this.swap(node, parentNode);
parent = Math.floor(node.queueIndex / 2);
}
};
PriorityQueue.prototype.swap = function (node1, node2) {
this._nodes[node1.queueIndex] = node2;
this._nodes[node2.queueIndex] = node1;
var temp = node1.queueIndex;
node1.queueIndex = node2.queueIndex;
node2.queueIndex = temp;
};
PriorityQueue.prototype.hasHigherPriority = function (higher, lower) {
return (higher.priority < lower.priority ||
(higher.priority == lower.priority && higher.insertionIndex < lower.insertionIndex));
};
return PriorityQueue;
}());
var Component = (function () { var Component = (function () {
function Component() { function Component() {
this._enabled = true; this._enabled = true;
@@ -1763,6 +2019,13 @@ var Matrix2D = (function () {
Matrix2D._identity = new Matrix2D(1, 0, 0, 1, 0, 0); Matrix2D._identity = new Matrix2D(1, 0, 0, 1, 0, 0);
return Matrix2D; return Matrix2D;
}()); }());
var Point = (function () {
function Point(x, y) {
this.x = x;
this.y = y;
}
return Point;
}());
var Vector2 = (function () { var Vector2 = (function () {
function Vector2(x, y) { function Vector2(x, y) {
this.x = 0; this.x = 0;

File diff suppressed because one or more lines are too long

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@@ -3,5 +3,18 @@ class MainScene extends Scene {
super(displayContent); super(displayContent);
this.addEntityProcessor(new SpawnerSystem(new Matcher())); this.addEntityProcessor(new SpawnerSystem(new Matcher()));
this.astarTest();
}
public astarTest(){
let graph = new AstarGridGraph(20, 20);
graph.weightedNodes.push(new Point(3, 3));
graph.weightedNodes.push(new Point(3, 4));
graph.weightedNodes.push(new Point(4, 3));
graph.weightedNodes.push(new Point(4, 4));
let path = graph.search(new Point(3, 4), new Point(15, 17));
console.log(path);
} }
} }

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@@ -3,10 +3,12 @@
"target": "es5", "target": "es5",
"outDir": "bin-debug", "outDir": "bin-debug",
"experimentalDecorators": true, "experimentalDecorators": true,
"emitDecoratorMetadata": true,
"lib": [ "lib": [
"es5", "es5",
"dom", "dom",
"es2015.promise" "es2015.promise",
"es6"
], ],
"types": [] "types": []
}, },

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@@ -17,6 +17,61 @@ declare interface Array<T> {
groupBy(keySelector: Function): Array<T>; groupBy(keySelector: Function): Array<T>;
sum(selector: any): any; sum(selector: any): any;
} }
declare class PriorityQueueNode {
priority: number;
insertionIndex: number;
queueIndex: number;
}
declare class AStarPathfinder {
static search<T>(graph: IAstarGraph<T>, start: T, goal: T): T[];
private static hasKey;
private static getKey;
static recontructPath<T>(cameFrom: Map<T, T>, start: T, goal: T): T[];
}
declare class AStarNode<T> extends PriorityQueueNode {
data: T;
constructor(data: T);
}
declare class AstarGridGraph implements IAstarGraph<Point> {
dirs: Point[];
walls: Point[];
weightedNodes: Point[];
defaultWeight: number;
weightedNodeWeight: number;
private _width;
private _height;
private _neighbors;
constructor(width: number, height: number);
isNodeInBounds(node: Point): boolean;
isNodePassable(node: Point): boolean;
search(start: Point, goal: Point): Point[];
getNeighbors(node: Point): Point[];
cost(from: Point, to: Point): number;
heuristic(node: Point, goal: Point): number;
}
interface IAstarGraph<T> {
getNeighbors(node: T): Array<T>;
cost(from: T, to: T): number;
heuristic(node: T, goal: T): any;
}
declare class PriorityQueue<T extends PriorityQueueNode> {
private _numNodes;
private _nodes;
private _numNodesEverEnqueued;
constructor(maxNodes: number);
clear(): void;
readonly count: number;
contains(node: T): boolean;
enqueue(node: T, priority: number): void;
dequeue(): T;
remove(node: T): void;
isValidQueue(): boolean;
private onNodeUpdated;
private cascadeDown;
private cascadeUp;
private swap;
private hasHigherPriority;
}
declare abstract class Component { declare abstract class Component {
entity: Entity; entity: Entity;
displayRender: egret.DisplayObject; displayRender: egret.DisplayObject;
@@ -338,6 +393,11 @@ declare class Matrix2D {
static createRotation(radians: number, result?: Matrix2D): Matrix2D; static createRotation(radians: number, result?: Matrix2D): Matrix2D;
static createScale(xScale: number, yScale: number, result?: Matrix2D): Matrix2D; static createScale(xScale: number, yScale: number, result?: Matrix2D): Matrix2D;
} }
declare class Point {
x: number;
y: number;
constructor(x: number, y: number);
}
declare class Vector2 { declare class Vector2 {
x: number; x: number;
y: number; y: number;

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@@ -238,6 +238,262 @@ Array.prototype.sum = function (selector) {
} }
return sum(this, selector); return sum(this, selector);
}; };
var PriorityQueueNode = (function () {
function PriorityQueueNode() {
this.priority = 0;
this.insertionIndex = 0;
this.queueIndex = 0;
}
return PriorityQueueNode;
}());
var AStarPathfinder = (function () {
function AStarPathfinder() {
}
AStarPathfinder.search = function (graph, start, goal) {
var _this = this;
var foundPath = false;
var cameFrom = new Map();
cameFrom.set(start, start);
var costSoFar = new Map();
var frontier = new PriorityQueue(1000);
frontier.enqueue(new AStarNode(start), 0);
costSoFar.set(start, 0);
var _loop_2 = function () {
var current = frontier.dequeue();
if (JSON.stringify(current.data) == JSON.stringify(goal)) {
foundPath = true;
return "break";
}
graph.getNeighbors(current.data).forEach(function (next) {
var newCost = costSoFar.get(current.data) + graph.cost(current.data, next);
if (!_this.hasKey(costSoFar, next) || newCost < costSoFar.get(next)) {
costSoFar.set(next, newCost);
var priority = newCost + graph.heuristic(next, goal);
frontier.enqueue(new AStarNode(next), priority);
cameFrom.set(next, current.data);
}
});
};
while (frontier.count > 0) {
var state_1 = _loop_2();
if (state_1 === "break")
break;
}
return foundPath ? this.recontructPath(cameFrom, start, goal) : null;
};
AStarPathfinder.hasKey = function (map, compareKey) {
var iterator = map.keys();
var r;
while (r = iterator.next(), !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return true;
}
return false;
};
AStarPathfinder.getKey = function (map, compareKey) {
var iterator = map.keys();
var valueIterator = map.values();
var r;
var v;
while (r = iterator.next(), v = valueIterator.next(), !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return v.value;
}
return null;
};
AStarPathfinder.recontructPath = function (cameFrom, start, goal) {
var path = [];
var current = goal;
path.push(goal);
while (current != start) {
current = this.getKey(cameFrom, current);
path.push(current);
}
path.reverse();
return path;
};
return AStarPathfinder;
}());
var AStarNode = (function (_super) {
__extends(AStarNode, _super);
function AStarNode(data) {
var _this = _super.call(this) || this;
_this.data = data;
return _this;
}
return AStarNode;
}(PriorityQueueNode));
var AstarGridGraph = (function () {
function AstarGridGraph(width, height) {
this.dirs = [
new Point(1, 0),
new Point(0, -1),
new Point(-1, 0),
new Point(0, 1)
];
this.walls = [];
this.weightedNodes = [];
this.defaultWeight = 1;
this.weightedNodeWeight = 5;
this._neighbors = new Array(4);
this._width = width;
this._height = height;
}
AstarGridGraph.prototype.isNodeInBounds = function (node) {
return 0 <= node.x && node.x < this._width && 0 <= node.y && node.y < this._height;
};
AstarGridGraph.prototype.isNodePassable = function (node) {
return !this.walls.contains(node);
};
AstarGridGraph.prototype.search = function (start, goal) {
return AStarPathfinder.search(this, start, goal);
};
AstarGridGraph.prototype.getNeighbors = function (node) {
var _this = this;
this._neighbors.length = 0;
this.dirs.forEach(function (dir) {
var next = new Point(node.x + dir.x, node.y + dir.y);
if (_this.isNodeInBounds(next) && _this.isNodePassable(next))
_this._neighbors.push(next);
});
return this._neighbors;
};
AstarGridGraph.prototype.cost = function (from, to) {
return this.weightedNodes.find(function (p) { return JSON.stringify(p) == JSON.stringify(to); }) ? this.weightedNodeWeight : this.defaultWeight;
};
AstarGridGraph.prototype.heuristic = function (node, goal) {
return Math.abs(node.x - goal.x) + Math.abs(node.y - goal.y);
};
return AstarGridGraph;
}());
var PriorityQueue = (function () {
function PriorityQueue(maxNodes) {
this._numNodes = 0;
this._nodes = new Array(maxNodes + 1);
this._numNodesEverEnqueued = 0;
}
PriorityQueue.prototype.clear = function () {
this._nodes.splice(1, this._numNodes);
this._numNodes = 0;
};
Object.defineProperty(PriorityQueue.prototype, "count", {
get: function () {
return this._numNodes;
},
enumerable: true,
configurable: true
});
PriorityQueue.prototype.contains = function (node) {
return (this._nodes[node.queueIndex] == node);
};
PriorityQueue.prototype.enqueue = function (node, priority) {
node.priority = priority;
this._numNodes++;
this._nodes[this._numNodes] = node;
node.queueIndex = this._numNodes;
node.insertionIndex = this._numNodesEverEnqueued++;
this.cascadeUp(this._nodes[this._numNodes]);
};
PriorityQueue.prototype.dequeue = function () {
var returnMe = this._nodes[1];
this.remove(returnMe);
return returnMe;
};
PriorityQueue.prototype.remove = function (node) {
if (node.queueIndex == this._numNodes) {
this._nodes[this._numNodes] = null;
this._numNodes--;
return;
}
var formerLastNode = this._nodes[this._numNodes];
this.swap(node, formerLastNode);
delete this._nodes[this._numNodes];
this._numNodes--;
this.onNodeUpdated(formerLastNode);
};
PriorityQueue.prototype.isValidQueue = function () {
for (var i = 1; i < this._nodes.length; i++) {
if (this._nodes[i]) {
var childLeftIndex = 2 * i;
if (childLeftIndex < this._nodes.length && this._nodes[childLeftIndex] &&
this.hasHigherPriority(this._nodes[childLeftIndex], this._nodes[i]))
return false;
var childRightIndex = childLeftIndex + 1;
if (childRightIndex < this._nodes.length && this._nodes[childRightIndex] &&
this.hasHigherPriority(this._nodes[childRightIndex], this._nodes[i]))
return false;
}
}
return true;
};
PriorityQueue.prototype.onNodeUpdated = function (node) {
var parentIndex = Math.floor(node.queueIndex / 2);
var parentNode = this._nodes[parentIndex];
if (parentIndex > 0 && this.hasHigherPriority(node, parentNode)) {
this.cascadeUp(node);
}
else {
this.cascadeDown(node);
}
};
PriorityQueue.prototype.cascadeDown = function (node) {
var newParent;
var finalQueueIndex = node.queueIndex;
while (true) {
newParent = node;
var childLeftIndex = 2 * finalQueueIndex;
if (childLeftIndex > this._numNodes) {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
var childLeft = this._nodes[childLeftIndex];
if (this.hasHigherPriority(childLeft, newParent)) {
newParent = childLeft;
}
var childRightIndex = childLeftIndex + 1;
if (childRightIndex <= this._numNodes) {
var childRight = this._nodes[childRightIndex];
if (this.hasHigherPriority(childRight, newParent)) {
newParent = childRight;
}
}
if (newParent != node) {
this._nodes[finalQueueIndex] = newParent;
var temp = newParent.queueIndex;
newParent.queueIndex = finalQueueIndex;
finalQueueIndex = temp;
}
else {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
}
};
PriorityQueue.prototype.cascadeUp = function (node) {
var parent = Math.floor(node.queueIndex / 2);
while (parent >= 1) {
var parentNode = this._nodes[parent];
if (this.hasHigherPriority(parentNode, node))
break;
this.swap(node, parentNode);
parent = Math.floor(node.queueIndex / 2);
}
};
PriorityQueue.prototype.swap = function (node1, node2) {
this._nodes[node1.queueIndex] = node2;
this._nodes[node2.queueIndex] = node1;
var temp = node1.queueIndex;
node1.queueIndex = node2.queueIndex;
node2.queueIndex = temp;
};
PriorityQueue.prototype.hasHigherPriority = function (higher, lower) {
return (higher.priority < lower.priority ||
(higher.priority == lower.priority && higher.insertionIndex < lower.insertionIndex));
};
return PriorityQueue;
}());
var Component = (function () { var Component = (function () {
function Component() { function Component() {
this._enabled = true; this._enabled = true;
@@ -1763,6 +2019,13 @@ var Matrix2D = (function () {
Matrix2D._identity = new Matrix2D(1, 0, 0, 1, 0, 0); Matrix2D._identity = new Matrix2D(1, 0, 0, 1, 0, 0);
return Matrix2D; return Matrix2D;
}()); }());
var Point = (function () {
function Point(x, y) {
this.x = x;
this.y = y;
}
return Point;
}());
var Vector2 = (function () { var Vector2 = (function () {
function Vector2(x, y) { function Vector2(x, y) {
this.x = 0; this.x = 0;

File diff suppressed because one or more lines are too long

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@@ -0,0 +1,89 @@
///<reference path="./PriorityQueueNode.ts" />
/**
* 计算路径给定的IAstarGraph和开始/目标位置
*/
class AStarPathfinder {
public static search<T>(graph: IAstarGraph<T>, start: T, goal: T){
let foundPath = false;
let cameFrom = new Map<T, T>();
cameFrom.set(start, start);
let costSoFar = new Map<T, number>();
let frontier = new PriorityQueue<AStarNode<T>>(1000);
frontier.enqueue(new AStarNode<T>(start), 0);
costSoFar.set(start, 0);
while (frontier.count > 0){
let current = frontier.dequeue();
if (JSON.stringify(current.data) == JSON.stringify(goal)){
foundPath = true;
break;
}
graph.getNeighbors(current.data).forEach(next => {
let newCost = costSoFar.get(current.data) + graph.cost(current.data, next);
if (!this.hasKey(costSoFar, next) || newCost < costSoFar.get(next)){
costSoFar.set(next, newCost);
let priority = newCost + graph.heuristic(next, goal);
frontier.enqueue(new AStarNode<T>(next), priority);
cameFrom.set(next, current.data);
}
});
}
return foundPath ? this.recontructPath(cameFrom, start, goal) : null;
}
private static hasKey<T>(map: Map<T, number>, compareKey: T){
let iterator = map.keys();
let r: IteratorResult<T>;
while (r = iterator.next() , !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return true;
}
return false;
}
private static getKey<T>(map: Map<T, T>, compareKey: T){
let iterator = map.keys();
let valueIterator = map.values();
let r: IteratorResult<T>;
let v: IteratorResult<T>;
while (r = iterator.next(), v = valueIterator.next(), !r.done) {
if (JSON.stringify(r.value) == JSON.stringify(compareKey))
return v.value;
}
return null;
}
public static recontructPath<T>(cameFrom: Map<T, T>, start: T, goal: T): T[]{
let path = [];
let current = goal;
path.push(goal);
while (current != start){
current = this.getKey(cameFrom, current);
path.push(current);
}
path.reverse();
return path;
}
}
/**
* 使用PriorityQueue需要的额外字段将原始数据封装在一个小类中
*/
class AStarNode<T> extends PriorityQueueNode {
public data: T;
constructor(data: T){
super();
this.data = data;
}
}

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/**
* 基本静态网格图与A*一起使用
* 将walls添加到walls HashSet并将加权节点添加到weightedNodes
*/
class AstarGridGraph implements IAstarGraph<Point> {
public dirs: Point[] = [
new Point(1, 0),
new Point(0, -1),
new Point(-1, 0),
new Point(0, 1)
];
public walls: Point[] = [];
public weightedNodes: Point[] = [];
public defaultWeight: number = 1;
public weightedNodeWeight = 5;
private _width;
private _height;
private _neighbors: Point[] = new Array(4);
constructor(width: number, height: number){
this._width = width;
this._height = height;
}
/**
* 确保节点在网格图的边界内
* @param node
*/
public isNodeInBounds(node: Point): boolean {
return 0 <= node.x && node.x < this._width && 0 <= node.y && node.y < this._height;
}
/**
* 检查节点是否可以通过。墙壁是不可逾越的。
* @param node
*/
public isNodePassable(node: Point): boolean {
return !this.walls.contains(node);
}
public search(start: Point, goal: Point){
return AStarPathfinder.search(this, start, goal);
}
public getNeighbors(node: Point): Point[] {
this._neighbors.length = 0;
this.dirs.forEach(dir => {
let next = new Point(node.x + dir.x, node.y + dir.y);
if (this.isNodeInBounds(next) && this.isNodePassable(next))
this._neighbors.push(next);
});
return this._neighbors;
}
public cost(from: Point, to: Point): number {
return this.weightedNodes.find((p)=> JSON.stringify(p) == JSON.stringify(to)) ? this.weightedNodeWeight : this.defaultWeight;
}
public heuristic(node: Point, goal: Point) {
return Math.abs(node.x - goal.x) + Math.abs(node.y - goal.y);
}
}

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interface IAstarGraph<T> {
getNeighbors(node: T): Array<T>;
cost(from: T, to: T): number;
heuristic(node: T, goal: T);
}

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class PriorityQueue<T extends PriorityQueueNode> {
private _numNodes: number;
private _nodes: T[];
private _numNodesEverEnqueued;
constructor(maxNodes: number) {
this._numNodes = 0;
this._nodes = new Array(maxNodes + 1);
this._numNodesEverEnqueued = 0;
}
public clear() {
this._nodes.splice(1, this._numNodes);
this._numNodes = 0;
}
public get count() {
return this._numNodes;
}
public contains(node: T): boolean {
return (this._nodes[node.queueIndex] == node);
}
public enqueue(node: T, priority: number) {
node.priority = priority;
this._numNodes++;
this._nodes[this._numNodes] = node;
node.queueIndex = this._numNodes;
node.insertionIndex = this._numNodesEverEnqueued++;
this.cascadeUp(this._nodes[this._numNodes]);
}
public dequeue(): T {
let returnMe = this._nodes[1];
this.remove(returnMe);
return returnMe;
}
public remove(node: T) {
if (node.queueIndex == this._numNodes) {
this._nodes[this._numNodes] = null;
this._numNodes--;
return;
}
let formerLastNode = this._nodes[this._numNodes];
this.swap(node, formerLastNode);
delete this._nodes[this._numNodes];
this._numNodes--;
this.onNodeUpdated(formerLastNode);
}
public isValidQueue(): boolean {
for (let i = 1; i < this._nodes.length; i++) {
if (this._nodes[i]) {
let childLeftIndex = 2 * i;
if (childLeftIndex < this._nodes.length && this._nodes[childLeftIndex] &&
this.hasHigherPriority(this._nodes[childLeftIndex], this._nodes[i]))
return false;
let childRightIndex = childLeftIndex + 1;
if (childRightIndex < this._nodes.length && this._nodes[childRightIndex] &&
this.hasHigherPriority(this._nodes[childRightIndex], this._nodes[i]))
return false;
}
}
return true;
}
private onNodeUpdated(node: T) {
let parentIndex = Math.floor(node.queueIndex / 2);
let parentNode = this._nodes[parentIndex];
if (parentIndex > 0 && this.hasHigherPriority(node, parentNode)) {
this.cascadeUp(node);
} else {
this.cascadeDown(node);
}
}
private cascadeDown(node: T) {
let newParent: T;
let finalQueueIndex = node.queueIndex;
while (true) {
newParent = node;
let childLeftIndex = 2 * finalQueueIndex;
if (childLeftIndex > this._numNodes) {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
let childLeft = this._nodes[childLeftIndex];
if (this.hasHigherPriority(childLeft, newParent)) {
newParent = childLeft;
}
let childRightIndex = childLeftIndex + 1;
if (childRightIndex <= this._numNodes) {
let childRight = this._nodes[childRightIndex];
if (this.hasHigherPriority(childRight, newParent)) {
newParent = childRight;
}
}
if (newParent != node) {
this._nodes[finalQueueIndex] = newParent;
let temp = newParent.queueIndex;
newParent.queueIndex = finalQueueIndex;
finalQueueIndex = temp;
} else {
node.queueIndex = finalQueueIndex;
this._nodes[finalQueueIndex] = node;
break;
}
}
}
private cascadeUp(node: T) {
let parent = Math.floor(node.queueIndex / 2);
while (parent >= 1) {
let parentNode = this._nodes[parent];
if (this.hasHigherPriority(parentNode, node))
break;
this.swap(node, parentNode);
parent = Math.floor(node.queueIndex / 2);
}
}
private swap(node1: T, node2: T) {
this._nodes[node1.queueIndex] = node2;
this._nodes[node2.queueIndex] = node1;
let temp = node1.queueIndex;
node1.queueIndex = node2.queueIndex;
node2.queueIndex = temp;
}
private hasHigherPriority(higher: T, lower: T) {
return (higher.priority < lower.priority ||
(higher.priority == lower.priority && higher.insertionIndex < lower.insertionIndex));
}
}

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class PriorityQueueNode {
/**
* 插入此节点的优先级。在将节点添加到队列之前必须设置
*/
public priority: number = 0;
/**
* 由优先级队列使用-不要编辑此值。表示插入节点的顺序
*/
public insertionIndex: number = 0;
/**
* 由优先级队列使用-不要编辑此值。表示队列中的当前位置
*/
public queueIndex: number = 0;
}

9
source/src/Math/Point.ts Normal file
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class Point {
public x: number;
public y: number;
constructor(x: number, y: number){
this.x = x;
this.y = y;
}
}