A Data-DrivenGame Object System

CDC 2013Soul Game

http://elvisqin.me

Scott Bilas, GDC 2002

Unity Cocos2d-x ...Cocos2d-x 3.0 alpha

Warrior,Goblin,Player... Scene

MVCEntity Component System

Game ObjectGameObject

AItree bullet monster player hero

GameObject

GameObjectGameObject

GameObject ID, GameObject.Find()GameObject

( )getChildByTag(), GameObject.Find()

Game Object System

?

( )

boss

helper

root-heavy blob pattern

hard coding database

Collision

AnimationAI

Render

Path finding

Input

ID

IDRender

Collision

AI

Path finding

Animation

Input

Entity Component System

EntityEntity ID

UI

class Entity:public Object { public: typedef std::string entity_id_type; static Entity* createWithId(const entity_id_type& id); const entity_id_type& getId(){return _id;} bool operator==(const Entity& entity){return _id==entity._id;} private: Entity(); Entity* initWithId(const entity_id_type& id); private: entity_id_type _id; };

ComponentComponent Entity

health, heromove

, render, collision, AI, move, gun, input...

class ECSComponent:public Object { protected: ECSComponent(const std::string& type); public: inline const std::string& getType() const{return _type;} private: std::string _type; };

ship

monster

bullet

helper

hero

level

healthcollisiongunscriptrendermovement ....

Entity Component Grid

EntityManager/** Manage all entity ids, and it's components */ class EntityManager:public Object { public: EntityManager(); ~EntityManager(); entity_id_type generateNewEid(); Entity* createEntity(); void removeEntity(Entity* entity); void addComponentToEntity(ECSComponent* component,Entity* entity);

/** an entity only can own one instane of some kind of component */ ECSComponent* getComponentForEntity(const std::string & eId,Entity* entity); /** get all entities which contain some kind of component. */ const std::vector<Entity*>* getAllEntitiesPosessingComponent(const std::string& cId); private: std::vector<Entity*> _entities; std::map<std::string, std::map<Entity*, ECSComponent*>*> _componentsByType; //for quick find entities every frame. std::map<std::string, std::vector<Entity*>*> _componentEntities; int _lowestUnassignedEid; };

SystemSystemSystemSystem Entity EntityCollisionSystem, AISystem, MoveSystem, InputSystem, BattleSystem,

CameraSystem... Code...

class ECSSystem:public Object { protected: ECSSystem(); void initWithManager(EntityManager*); public: virtual void configure(){}; virtual void update(float dt){}; protected: EntityManager* _entityManager; };

ECS(Byte56 stackoverflow)

System ( )

Calculations collision detection

Collision

Render

CollisionSystemPosition

Entity ( )

Entity ID: 88 Entity

Collision

Render

CollisionSystem Id 88 Entity

Position

void CollisionSystem::update(float dt) { Array* entities=_entityManager->getAllEntitiesPosessingComponent(CollisionComponent::COLLISION_TYPE); if(!entities) return; int count=entities->count(); //记录两个Entity之间是否已执⾏碰撞检测 int haveCollision[count][count]; for (int i=0; i<count; i++){ //碰撞主体 Entity* entity=(Entity*)entities->getObjectAtIndex(i); RenderComponent* render=(RenderComponent*)_entityManager->getComponentForEntity(RenderComponent::RENDER_TYPE, entity); if(!render) continue; //可能与之发⽣碰撞的主体 for (int j=0; j<count; j++) { if (haveCollision[j][i]==1||i==j) { continue; } Entity* collisionEntity=(Entity*)entities->getObjectAtIndex(j); RenderComponent* collisionRender=(RenderComponent*)_entityManager->getComponentForEntity(RenderComponent::RENDER_TYPE, collisionEntity); if(!collisionRender) continue; //发⽣碰撞 if (collide(render->getNode(), collisionRender->getNode())) { //标记已处理两个特定Entity haveCollision[i][j]=1; CollisionEvent* event=new CollisionEvent(entity,collisionEntity); EventDispatcher::getInstance()->dispatchEvent(event); } } } }

Collision

Render

Position

System

Renderentity1entity2entity3

Collisionentity1entity2entity3

Moveentity1entity2entity3

Move

Health

Render

Move

Health

EntityManager ComponentSystem

GameEngineLoop

Entity SpriteEntity SystemgetChildByTag GameObject.FindSystem Component Sprite tag name

ID NameEntity UI UI

UI Sprite UI

System

EventDispatcherGunEvent, DeadEvent,CollisionEvent…

Systemconfigure EventDispatcher

thisECS

Cocos2d-x 3.0 alpha

SystemSystem

thisEntity

CCCalFuncNC++11 lambda

DemoEntity( Render ship ghost)

ghost MoveComponentghost GunComponent

girlCocosd-x 3.0 alpha

http://github.com/elvisqin/entitysystem

ECSSystemUI

mouse touch

ECS EventDispatcher

Unity GameObject name

( )

prefabUI

Unity

<?xml version="1.0"?><entity> <Render> <Sprite>Ghost/ghost.png</Sprite> </Render> <Health> <curHP>20</curHP> <maxHP>20</maxHP> </Health> <Move></Move> <Collision/> <Ghost/> <Gun> <distance>100</distance> <targetType>ship</targetType> </Gun></entity>

Entity* unit = _entityManager->createEntity(); _entityManager->addComponentToEntity(RenderComponent::create(unitSprite), unit); //UI _entityManager->addComponentToEntity(HealthComponent::create(20,20),unit); //⽣命值 _entityManager->addComponentToEntity(MoveComponent::cretae(ship->getPosition(),1), unit); //可移动 _entityManager->addComponentToEntity(CollisionComponent::create(), unit); //可碰撞 _entityManager->addComponentToEntity(HitComponent::create(ShipComponent::SHIP_TYPE, 10), unit); //碰撞攻击伤害及⺫标 _entityManager->addComponentToEntity(GhostComponent::create(), unit); //单位类型 _entityManager->addComponentToEntity(GunComponent::create(ShipComponent::SHIP_TYPE, 1000, 0.2), unit);

System Entitystd::map size

EntityManagerSystem Entity(Unity )Cocos2d-x 2.1.2 CCNode

EventDispatcher

Entity SystemSprite Kit , …

2.5D

C++ Style STL lamdaGUI

LabelCocoStudiomore…

Cocos2d-x 3.0

thanks&enjoy