Merge remote-tracking branch 'origin/master' into issue-94-响应式查询(Reactive_Query_System)/_Event-driven_Query

This commit is contained in:
YHH
2025-10-14 17:51:59 +08:00
5 changed files with 508 additions and 6 deletions

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@@ -66,6 +66,7 @@ export default defineConfig({
items: [ items: [
{ text: '实体类 (Entity)', link: '/guide/entity' }, { text: '实体类 (Entity)', link: '/guide/entity' },
{ text: '组件系统 (Component)', link: '/guide/component' }, { text: '组件系统 (Component)', link: '/guide/component' },
{ text: '实体查询系统', link: '/guide/entity-query' },
{ {
text: '系统架构 (System)', text: '系统架构 (System)',
link: '/guide/system', link: '/guide/system',

501
docs/guide/entity-query.md Normal file
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@@ -0,0 +1,501 @@
# 实体查询系统
实体查询是 ECS 架构的核心功能之一。本指南将介绍如何使用 Matcher 和 QuerySystem 来查询和筛选实体。
## 核心概念
### Matcher - 查询条件描述符
Matcher 是一个链式 API,用于描述实体查询条件。它本身不执行查询,而是作为条件传递给 EntitySystem 或 QuerySystem。
### QuerySystem - 查询执行引擎
QuerySystem 负责实际执行查询,内部使用响应式查询机制自动优化性能。
## 在 EntitySystem 中使用 Matcher
这是最常见的使用方式。EntitySystem 通过 Matcher 自动筛选和处理符合条件的实体。
### 基础用法
```typescript
import { EntitySystem, Matcher, Entity, Component } from '@esengine/ecs-framework';
class PositionComponent extends Component {
public x: number = 0;
public y: number = 0;
}
class VelocityComponent extends Component {
public vx: number = 0;
public vy: number = 0;
}
class MovementSystem extends EntitySystem {
constructor() {
// 方式1: 使用 Matcher.empty().all()
super(Matcher.empty().all(PositionComponent, VelocityComponent));
// 方式2: 直接使用 Matcher.all() (等价)
// super(Matcher.all(PositionComponent, VelocityComponent));
}
protected process(entities: readonly Entity[]): void {
for (const entity of entities) {
const pos = entity.getComponent(PositionComponent)!;
const vel = entity.getComponent(VelocityComponent)!;
pos.x += vel.vx;
pos.y += vel.vy;
}
}
}
// 添加到场景
scene.addEntityProcessor(new MovementSystem());
```
### Matcher 链式 API
#### all() - 必须包含所有组件
```typescript
class HealthSystem extends EntitySystem {
constructor() {
// 实体必须同时拥有 Health 和 Position 组件
super(Matcher.empty().all(HealthComponent, PositionComponent));
}
protected process(entities: readonly Entity[]): void {
// 只处理同时拥有两个组件的实体
}
}
```
#### any() - 至少包含一个组件
```typescript
class DamageableSystem extends EntitySystem {
constructor() {
// 实体至少拥有 Health 或 Shield 其中之一
super(Matcher.any(HealthComponent, ShieldComponent));
}
protected process(entities: readonly Entity[]): void {
// 处理拥有生命值或护盾的实体
}
}
```
#### none() - 不能包含指定组件
```typescript
class AliveEntitySystem extends EntitySystem {
constructor() {
// 实体不能拥有 DeadTag 组件
super(Matcher.all(HealthComponent).none(DeadTag));
}
protected process(entities: readonly Entity[]): void {
// 只处理活着的实体
}
}
```
#### 组合条件
```typescript
class CombatSystem extends EntitySystem {
constructor() {
super(
Matcher.empty()
.all(PositionComponent, HealthComponent) // 必须有位置和生命
.any(WeaponComponent, MagicComponent) // 至少有武器或魔法
.none(DeadTag, FrozenTag) // 不能是死亡或冰冻状态
);
}
protected process(entities: readonly Entity[]): void {
// 处理可以战斗的活着的实体
}
}
```
### 按标签查询
```typescript
class PlayerSystem extends EntitySystem {
constructor() {
// 查询特定标签的实体
super(Matcher.empty().withTag(Tags.PLAYER));
}
protected process(entities: readonly Entity[]): void {
// 只处理玩家实体
}
}
```
### 按名称查询
```typescript
class BossSystem extends EntitySystem {
constructor() {
// 查询特定名称的实体
super(Matcher.empty().withName('Boss'));
}
protected process(entities: readonly Entity[]): void {
// 只处理名为 'Boss' 的实体
}
}
```
## 直接使用 QuerySystem
如果不需要创建系统,可以直接使用 Scene 的 querySystem 进行查询。
### 基础查询方法
```typescript
// 获取场景的查询系统
const querySystem = scene.querySystem;
// 查询拥有所有指定组件的实体
const result1 = querySystem.queryAll(PositionComponent, VelocityComponent);
console.log(`找到 ${result1.count} 个移动实体`);
console.log(`查询耗时: ${result1.executionTime.toFixed(2)}ms`);
// 查询拥有任意指定组件的实体
const result2 = querySystem.queryAny(WeaponComponent, MagicComponent);
console.log(`找到 ${result2.count} 个战斗单位`);
// 查询不包含指定组件的实体
const result3 = querySystem.queryNone(DeadTag);
console.log(`找到 ${result3.count} 个活着的实体`);
```
### 按标签查询
```typescript
const playerResult = querySystem.queryByTag(Tags.PLAYER);
for (const player of playerResult.entities) {
console.log('玩家:', player.name);
}
```
### 按名称查询
```typescript
const bossResult = querySystem.queryByName('Boss');
if (bossResult.count > 0) {
const boss = bossResult.entities[0];
console.log('找到Boss:', boss);
}
```
### 按单个组件查询
```typescript
const healthResult = querySystem.queryByComponent(HealthComponent);
console.log(`${healthResult.count} 个实体拥有生命值`);
```
## 性能优化
### 自动缓存
QuerySystem 内部使用响应式查询自动缓存结果,相同的查询条件会直接使用缓存:
```typescript
// 第一次查询,执行实际查询
const result1 = querySystem.queryAll(PositionComponent);
console.log('fromCache:', result1.fromCache); // false
// 第二次相同查询,使用缓存
const result2 = querySystem.queryAll(PositionComponent);
console.log('fromCache:', result2.fromCache); // true
```
### 实体变化自动更新
当实体添加/移除组件时,查询缓存会自动更新:
```typescript
// 查询拥有武器的实体
const before = querySystem.queryAll(WeaponComponent);
console.log('之前:', before.count); // 假设为 5
// 给实体添加武器
const enemy = scene.createEntity('Enemy');
enemy.addComponent(new WeaponComponent());
// 再次查询,自动包含新实体
const after = querySystem.queryAll(WeaponComponent);
console.log('之后:', after.count); // 现在是 6
```
### 查询性能统计
```typescript
const stats = querySystem.getStats();
console.log('总查询次数:', stats.queryStats.totalQueries);
console.log('缓存命中率:', stats.queryStats.cacheHitRate);
console.log('缓存大小:', stats.cacheStats.size);
```
## 实际应用场景
### 场景1: 物理系统
```typescript
class PhysicsSystem extends EntitySystem {
constructor() {
super(Matcher.empty().all(TransformComponent, RigidbodyComponent));
}
protected process(entities: readonly Entity[]): void {
for (const entity of entities) {
const transform = entity.getComponent(TransformComponent)!;
const rigidbody = entity.getComponent(RigidbodyComponent)!;
// 应用重力
rigidbody.velocity.y -= 9.8 * Time.deltaTime;
// 更新位置
transform.position.x += rigidbody.velocity.x * Time.deltaTime;
transform.position.y += rigidbody.velocity.y * Time.deltaTime;
}
}
}
```
### 场景2: 渲染系统
```typescript
class RenderSystem extends EntitySystem {
constructor() {
super(
Matcher.empty()
.all(TransformComponent, SpriteComponent)
.none(InvisibleTag) // 排除不可见实体
);
}
protected process(entities: readonly Entity[]): void {
// 按 z-order 排序
const sorted = entities.slice().sort((a, b) => {
const zA = a.getComponent(TransformComponent)!.z;
const zB = b.getComponent(TransformComponent)!.z;
return zA - zB;
});
// 渲染实体
for (const entity of sorted) {
const transform = entity.getComponent(TransformComponent)!;
const sprite = entity.getComponent(SpriteComponent)!;
renderer.drawSprite(sprite.texture, transform.position);
}
}
}
```
### 场景3: 碰撞检测
```typescript
class CollisionSystem extends EntitySystem {
constructor() {
super(Matcher.empty().all(TransformComponent, ColliderComponent));
}
protected process(entities: readonly Entity[]): void {
// 简单的 O(n²) 碰撞检测
for (let i = 0; i < entities.length; i++) {
for (let j = i + 1; j < entities.length; j++) {
this.checkCollision(entities[i], entities[j]);
}
}
}
private checkCollision(a: Entity, b: Entity): void {
const transA = a.getComponent(TransformComponent)!;
const transB = b.getComponent(TransformComponent)!;
const colliderA = a.getComponent(ColliderComponent)!;
const colliderB = b.getComponent(ColliderComponent)!;
if (this.isOverlapping(transA, colliderA, transB, colliderB)) {
// 触发碰撞事件
scene.eventSystem.emit('collision', { entityA: a, entityB: b });
}
}
private isOverlapping(...args: any[]): boolean {
// 碰撞检测逻辑
return false;
}
}
```
### 场景4: 一次性查询
```typescript
// 在系统外部执行一次性查询
class GameManager {
private scene: Scene;
public countEnemies(): number {
const result = this.scene.querySystem.queryByTag(Tags.ENEMY);
return result.count;
}
public findNearestEnemy(playerPos: Vector2): Entity | null {
const enemies = this.scene.querySystem.queryByTag(Tags.ENEMY);
let nearest: Entity | null = null;
let minDistance = Infinity;
for (const enemy of enemies.entities) {
const transform = enemy.getComponent(TransformComponent);
if (!transform) continue;
const distance = Vector2.distance(playerPos, transform.position);
if (distance < minDistance) {
minDistance = distance;
nearest = enemy;
}
}
return nearest;
}
}
```
## 最佳实践
### 1. 优先使用 EntitySystem
```typescript
// 推荐: 使用 EntitySystem
class GoodSystem extends EntitySystem {
constructor() {
super(Matcher.empty().all(HealthComponent));
}
protected process(entities: readonly Entity[]): void {
// 自动获得符合条件的实体,每帧自动更新
}
}
// 不推荐: 在 update 中手动查询
class BadSystem extends EntitySystem {
constructor() {
super(Matcher.empty());
}
protected process(entities: readonly Entity[]): void {
// 每帧手动查询,浪费性能
const result = this.scene!.querySystem.queryAll(HealthComponent);
for (const entity of result.entities) {
// ...
}
}
}
```
### 2. 合理使用 none() 排除条件
```typescript
// 排除已死亡的敌人
class EnemyAISystem extends EntitySystem {
constructor() {
super(
Matcher.empty()
.all(EnemyTag, AIComponent)
.none(DeadTag) // 不处理死亡的敌人
);
}
}
```
### 3. 使用标签优化查询
```typescript
// 不好: 查询所有实体再过滤
const allEntities = scene.querySystem.getAllEntities();
const players = allEntities.filter(e => e.hasComponent(PlayerTag));
// 好: 直接按标签查询
const players = scene.querySystem.queryByTag(Tags.PLAYER).entities;
```
### 4. 避免过于复杂的查询条件
```typescript
// 不推荐: 过于复杂
super(
Matcher.empty()
.all(A, B, C, D)
.any(E, F, G)
.none(H, I, J)
);
// 推荐: 拆分成多个简单系统
class SystemAB extends EntitySystem {
constructor() {
super(Matcher.empty().all(A, B));
}
}
class SystemCD extends EntitySystem {
constructor() {
super(Matcher.empty().all(C, D));
}
}
```
## 注意事项
### 1. 查询结果是只读的
```typescript
const result = querySystem.queryAll(PositionComponent);
// 不要修改返回的数组
result.entities.push(someEntity); // 错误!
// 如果需要修改,先复制
const mutableArray = [...result.entities];
mutableArray.push(someEntity); // 正确
```
### 2. 组件添加/移除后的查询时机
```typescript
// 创建实体并添加组件
const entity = scene.createEntity('Player');
entity.addComponent(new PositionComponent());
// 立即查询可能获取到新实体
const result = scene.querySystem.queryAll(PositionComponent);
// result.entities 包含新创建的实体
```
### 3. Matcher 是不可变的
```typescript
const matcher = Matcher.empty().all(PositionComponent);
// 链式调用返回新的 Matcher 实例
const matcher2 = matcher.any(VelocityComponent);
// matcher 本身不变
console.log(matcher === matcher2); // false
```
## 相关 API
- [Matcher](../api/classes/Matcher.md) - 查询条件描述符 API 参考
- [QuerySystem](../api/classes/QuerySystem.md) - 查询系统 API 参考
- [EntitySystem](../api/classes/EntitySystem.md) - 实体系统 API 参考
- [Entity](../api/classes/Entity.md) - 实体 API 参考

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@@ -75,7 +75,7 @@ export interface SystemMetadata {
* @ECSSystem('Physics', { updateOrder: 10 }) * @ECSSystem('Physics', { updateOrder: 10 })
* class PhysicsSystem extends EntitySystem { * class PhysicsSystem extends EntitySystem {
* constructor(@Inject(CollisionSystem) private collision: CollisionSystem) { * constructor(@Inject(CollisionSystem) private collision: CollisionSystem) {
* super(Matcher.of(Transform, RigidBody)); * super(Matcher.empty().all(Transform, RigidBody));
* } * }
* } * }
* ``` * ```

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@@ -527,7 +527,7 @@ export class Scene implements IScene {
* @Injectable() * @Injectable()
* class PhysicsSystem extends EntitySystem { * class PhysicsSystem extends EntitySystem {
* constructor(@Inject(CollisionSystem) private collision: CollisionSystem) { * constructor(@Inject(CollisionSystem) private collision: CollisionSystem) {
* super(Matcher.of(Transform)); * super(Matcher.empty().all(Transform));
* } * }
* } * }
* scene.addEntityProcessor(PhysicsSystem); * scene.addEntityProcessor(PhysicsSystem);
@@ -613,7 +613,7 @@ export class Scene implements IScene {
* @Injectable() * @Injectable()
* @ECSSystem('Collision', { updateOrder: 5 }) * @ECSSystem('Collision', { updateOrder: 5 })
* class CollisionSystem extends EntitySystem implements IService { * class CollisionSystem extends EntitySystem implements IService {
* constructor() { super(Matcher.of(Collider)); } * constructor() { super(Matcher.empty().all(Collider)); }
* dispose() {} * dispose() {}
* } * }
* *
@@ -621,7 +621,7 @@ export class Scene implements IScene {
* @ECSSystem('Physics', { updateOrder: 10 }) * @ECSSystem('Physics', { updateOrder: 10 })
* class PhysicsSystem extends EntitySystem implements IService { * class PhysicsSystem extends EntitySystem implements IService {
* constructor(@Inject(CollisionSystem) private collision: CollisionSystem) { * constructor(@Inject(CollisionSystem) private collision: CollisionSystem) {
* super(Matcher.of(Transform, RigidBody)); * super(Matcher.empty().all(Transform, RigidBody));
* } * }
* dispose() {} * dispose() {}
* } * }

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@@ -36,7 +36,7 @@ interface EventListenerRecord {
* // 传统方式 * // 传统方式
* class MovementSystem extends EntitySystem { * class MovementSystem extends EntitySystem {
* constructor() { * constructor() {
* super(Matcher.of(Transform, Velocity)); * super(Matcher.empty().all(Transform, Velocity));
* } * }
* *
* protected process(entities: readonly Entity[]): void { * protected process(entities: readonly Entity[]): void {
@@ -51,7 +51,7 @@ interface EventListenerRecord {
* // 类型安全方式 * // 类型安全方式
* class MovementSystem extends EntitySystem<[typeof Transform, typeof Velocity]> { * class MovementSystem extends EntitySystem<[typeof Transform, typeof Velocity]> {
* constructor() { * constructor() {
* super(Matcher.of(Transform, Velocity)); * super(Matcher.empty().all(Transform, Velocity));
* } * }
* *
* protected process(entities: readonly Entity[]): void { * protected process(entities: readonly Entity[]): void {