feat(gameplay): add entity destruction support

include/Cubed/gameplay/client_entity_manager.hpp

@@ -10,7 +10,7 @@ namespace Cubed {
 class ClientWorld;
 class ClientEntityManager {
 public:
-    enum class Command { CREATE };
+    enum class Command { CREATE, DESTORY };
 
     ClientEntityManager(ClientWorld& world);
     void update();
@@ -19,7 +19,7 @@ public:
     void add_entity(EntityID id, std::string_view name, const glm::vec3& pos);
 
     void receive_entity_create(S2CEntityCreate& s2c);
-
+    void destory(EntityID id);
     const entt::registry& get_registry() const;
 
 private:
@@ -32,7 +32,7 @@ private:
     using acc = EntityMap::accessor;
     using cacc = EntityMap::const_accessor;
     using CreateFunc = std::function<void(EntityID id)>;
-    using TaskElement = std::variant<EntityCreateElement>;
+    using TaskElement = std::variant<EntityCreateElement, EntityID>;
     using TaskPair = std::pair<Command, TaskElement>;
 
     ClientWorld& m_world;
@@ -42,7 +42,7 @@ private:
     tbb::concurrent_queue<TaskPair> m_tasks;
 
     void handle_task();
-
+    void handle_entity_destory(EntityID id);
     template <typename... Args>
     void create_entity_in_registry(EntityID id, Args&&... args) {
         {

include/Cubed/gameplay/packet.hpp

@@ -62,6 +62,7 @@ enum class PacketEnum : uint16_t {
     S2C_CLEAR_ALL_CHUNKS = 3005,
     UPDATE_TIME = 3006,
     S2C_ENTITY_CREATE = 3007,
+    S2C_ENTITY_DESTORY = 3008,
     CHAT_MSG = 4001,
     VOICE_MSG = 4002,
     PING = 9001,
@@ -115,6 +116,9 @@ template <> constexpr uint16_t get_packet_id<S2C_ClearAllChunks>() {
 template <> constexpr uint16_t get_packet_id<S2CEntityCreate>() {
     return std::to_underlying(PacketEnum::S2C_ENTITY_CREATE);
 }
+template <> constexpr uint16_t get_packet_id<S2CEntityDestory>() {
+    return std::to_underlying(PacketEnum::S2C_ENTITY_DESTORY);
+}
 template <> constexpr uint16_t get_packet_id<UpdateTime>() {
     return std::to_underlying(PacketEnum::UPDATE_TIME);
 }

include/Cubed/gameplay/server_entity_manager.hpp

@@ -16,11 +16,11 @@ public:
     void update();
     // not thread safe
     void add_entity(std::string_view name, const glm::vec3& pos);
-
+    void destory(EntityID id);
     void handle_player_login(std::shared_ptr<Session> session);
 
 private:
-    enum class Command { CREATE, SEND_ALL_ENTITIES };
+    enum class Command { CREATE, SEND_ALL_ENTITIES, DESTORY };
     struct EntityCreateElement {
         std::string name;
         glm::vec3 pos;
@@ -30,7 +30,7 @@ private:
     using cacc = EntityMap::const_accessor;
     using CreateFunc = std::function<EntityID()>;
     using TaskElement =
-        std::variant<std::shared_ptr<Session>, EntityCreateElement>;
+        std::variant<std::shared_ptr<Session>, EntityCreateElement, EntityID>;
     using TaskPair = std::pair<Command, TaskElement>;
     ServerWorld& m_world;
     tbb::concurrent_queue<TaskPair> m_tasks;
@@ -39,8 +39,9 @@ private:
     EntityMap m_entities;
     std::unordered_map<std::string_view, CreateFunc> m_factories;
     void create_entity(std::string_view name, const glm::vec3& pos);
-    void send_entity_create(EntityID id, std::string_view name,
+    void handle_entity_create(EntityID id, std::string_view name,
                               const glm::vec3& pos);
+    void handle_entity_destory(EntityID id);
     void handle_task();
     void send_all_entities(std::shared_ptr<Session>& session);
     template <typename... Args> EntityID add_entity(Args&&... args) {

src/gameplay/client_entity_manager.cpp

@@ -39,19 +39,38 @@ void ClientEntityManager::receive_entity_create(S2CEntityCreate& s2c) {
     m_tasks.emplace(Command::CREATE, std::move(c));
 }
 
+void ClientEntityManager::destory(EntityID id) {
+    m_tasks.emplace(Command::DESTORY, id);
+}
+
 void ClientEntityManager::handle_task() {
     TaskPair pair;
     while (m_tasks.try_pop(pair)) {
         switch (pair.first) {
-        case Command::CREATE:
+        case Command::CREATE: {
             auto* p = std::get_if<EntityCreateElement>(&pair.second);
             ASSERT(p);
             add_entity(p->id, p->name, p->pos);
-            break;
+
+        } break;
+        case Command::DESTORY: {
+            auto* p = std::get_if<EntityID>(&pair.second);
+            ASSERT(p);
+            handle_entity_destory(*p);
+        } break;
         }
     }
 }
 
+void ClientEntityManager::handle_entity_destory(EntityID id) {
+    acc a;
+    if (!m_entities.find(a, id)) {
+        return;
+    }
+    m_registry.destroy(a->second);
+    m_entities.erase(a);
+}
+
 const entt::registry& ClientEntityManager::get_registry() const {
     return m_registry;
 }

src/gameplay/network_client.cpp

@@ -150,6 +150,12 @@ asio::awaitable<void> NetworkClient::read_loop() {
                 }
 
             } break;
+            case std::to_underlying(PacketEnum::S2C_ENTITY_DESTORY): {
+                auto* msg = Arena::Create<S2CEntityDestory>(&arena);
+                if (decode_packet(*msg, body_data, header)) {
+                    m_world.entity_manager().destory(msg->id());
+                }
+            } break;
             }
         }
     } catch (const asio::system_error& e) {

src/gameplay/server_entity_manager.cpp

@@ -37,6 +37,11 @@ void ServerEntityManager::handle_task() {
             ASSERT(c);
             send_all_entities(*c);
         } break;
+        case Command::DESTORY: {
+            auto* c = std::get_if<EntityID>(&pair.second);
+            ASSERT(c);
+            handle_entity_destory(*c);
+        } break;
         }
     }
 }
@@ -47,6 +52,10 @@ void ServerEntityManager::add_entity(std::string_view name,
                     EntityCreateElement{std::string(name), pos});
 }
 
+void ServerEntityManager::destory(EntityID id) {
+    m_tasks.emplace(Command::DESTORY, id);
+}
+
 void ServerEntityManager::handle_player_login(
     std::shared_ptr<Session> session) {
     m_tasks.emplace(Command::SEND_ALL_ENTITIES, std::move(session));
@@ -62,7 +71,7 @@ void ServerEntityManager::create_entity(std::string_view name,
         ASSERT(t);
         t->transform.position.value = pos;
     }
-    send_entity_create(e, name, pos);
+    handle_entity_create(e, name, pos);
 }
 
 void ServerEntityManager::send_all_entities(std::shared_ptr<Session>& session) {
@@ -79,7 +88,8 @@ void ServerEntityManager::send_all_entities(std::shared_ptr<Session>& session) {
     }
 }
 
-void ServerEntityManager::send_entity_create(EntityID id, std::string_view name,
+void ServerEntityManager::handle_entity_create(EntityID id,
+                                               std::string_view name,
                                                const glm::vec3& pos) {
     auto sessions = m_world.get_all_session();
 
@@ -94,4 +104,20 @@ void ServerEntityManager::send_entity_create(EntityID id, std::string_view name,
     }
 }
 
+void ServerEntityManager::handle_entity_destory(EntityID id) {
+    acc a;
+    if (!m_entities.find(a, id)) {
+        return;
+    }
+    m_registry.destroy(a->second);
+    m_entities.erase(a);
+    auto sessions = m_world.get_all_session();
+    Arena arena;
+    auto* s2c = Arena::Create<S2CEntityDestory>(&arena);
+    s2c->set_id(id);
+    for (auto& s : sessions) {
+        s->send(make_packet(*s2c));
+    }
+}
+
 } // namespace Cubed

src/proto/world/entity.proto

@@ -7,3 +7,7 @@ message S2CEntityCreate {
     string name = 2;
     Vec3 pos = 3;
 }
+
+message S2CEntityDestory {
+    uint64 id = 1;
+}