feat(gameplay): add packet to clear all chunks on server rebuild

Add new packet S2C_ClearAllChunks (ID 3005) to notify clients when the server rebuilds its world. Clients respond by clearing their chunk cache and requesting fresh chunks. Shift UPDATE_TIME packet ID to 3006 to accommodate.

include/Cubed/gameplay/client_world.hpp

@@ -37,6 +37,8 @@ public:
     bool can_pass_block(const glm::ivec3& block_pos) const;
     BlockType get_block_tpye(const glm::ivec3& block_pos) const;
 
+    void rebuild_world();
+
     void push_delete_vbo(GLuint vbo);
     void push_delete_vao(GLuint vao);
     // void hot_reload();
@@ -105,6 +107,7 @@ private:
     std::atomic<TickType> m_game_ticks{0};
     std::atomic<TickType> m_day_tick{6000};
     std::atomic<bool> m_requesting_chunk{false};
+    std::atomic<bool> m_is_rebuilding{false};
     std::shared_ptr<NetworkClient> m_client;
     ChunkLoadStyle m_chunk_load_style{ChunkLoadStyle::CENTER};
 

include/Cubed/gameplay/packet.hpp

@@ -52,7 +52,8 @@ enum class PacketEnum : uint16_t {
     CHUNK_DATA_RSP = 3002,
     BLOCK_CHANGE_REQ = 3003,
     BLOCK_CHANGE_RSP = 3004,
-    UPDATE_TIME = 3005,
+    S2C_CLEAR_ALL_CHUNKS = 3005,
+    UPDATE_TIME = 3006,
     PING = 9001,
     PONG = 9002
 
@@ -98,6 +99,9 @@ template <> constexpr uint16_t get_packet_id<BlockChangeReq>() {
 template <> constexpr uint16_t get_packet_id<BlockChangeRsp>() {
     return std::to_underlying(PacketEnum::BLOCK_CHANGE_RSP);
 }
+template <> constexpr uint16_t get_packet_id<S2C_ClearAllChunks>() {
+    return std::to_underlying(PacketEnum::S2C_CLEAR_ALL_CHUNKS);
+}
 template <> constexpr uint16_t get_packet_id<UpdateTime>() {
     return std::to_underlying(PacketEnum::UPDATE_TIME);
 }

src/gameplay/client_world.cpp

@@ -104,6 +104,25 @@ bool ClientWorld::can_pass_block(const glm::ivec3& block_pos) const {
     auto id = chunk_blocks[ClientChunk::index(x, y, z)];
     return BlockManager::is_passable(id);
 }
+
+void ClientWorld::rebuild_world() {
+    if (m_is_rebuilding.exchange(true)) {
+        return;
+    }
+    stop_thread_pool();
+    {
+        std::lock_guard lk(m_chunks_mutex);
+        m_chunks.clear();
+    }
+    {
+        std::lock_guard lock(m_pending_upload_queue_mutex);
+        m_pending_upload_queue.clear();
+    }
+    start_thread_pool();
+    request_chunk();
+    m_is_rebuilding = false;
+}
+
 BlockType ClientWorld::get_block_tpye(const glm::ivec3& block_pos) const {
     auto [chunk_x, chunk_z] = get_chunk_pos(block_pos.x, block_pos.z);
     std::shared_lock lk(m_chunks_mutex);

src/gameplay/network_client.cpp

@@ -78,8 +78,8 @@ asio::awaitable<void> NetworkClient::read_loop() {
             } break;
             case to_num(PacketEnum::CHUNK_DATA_RSP): {
                 ChunkDataRsp rsp;
-                Logger::info("Client: Receive Chunk Data rsp, size {}mb",
+                // Logger::info("Client: Receive Chunk Data rsp, size {}mb",
-                             body_data.size() / 1024.0f / 1024);
+                //              body_data.size() / 1024.0f / 1024);
                 if (decode_packet(rsp, body_data, header)) {
                     m_world.receive_chunk(std::move(rsp));
                 }
@@ -109,6 +109,15 @@ asio::awaitable<void> NetworkClient::read_loop() {
                     m_world.receive_player_logout(*rsp);
                 }
             } break;
+            case to_num(PacketEnum::S2C_CLEAR_ALL_CHUNKS): {
+                auto* rsp = Arena::Create<S2C_ClearAllChunks>(&arena);
+                if (decode_packet(*rsp, body_data, header)) {
+                    if (rsp->clear()) {
+                        Logger::info("Client Clear All Chunk");
+                        m_world.rebuild_world();
+                    }
+                }
+            } break;
             }
         }
     } catch (const asio::system_error& e) {

src/gameplay/server_world.cpp

@@ -392,6 +392,16 @@ void ServerWorld::rebuild_world() {
     start_thread_pool();
     start_gen_thread();
     need_gen(std::nullopt);
+    Arena arena;
+    auto* rsp = Arena::Create<S2C_ClearAllChunks>(&arena);
+    rsp->set_clear(true);
+    {
+        std::lock_guard lock(m_player_mutex);
+        for (auto& [uuid, player] : m_players) {
+            player.get_session()->send(make_packet(*rsp));
+        }
+    }
+
     m_is_rebuilding = false;
 }
 

src/proto/world/chunk_data.proto

@@ -17,3 +17,7 @@ message ChunkDataRsp {
     repeated uint32 neighbor_blocks_3 = 7 [packed=true];
     repeated uint32 neighbor_blocks_4 = 8 [packed=true];
 }
+
+message S2C_ClearAllChunks {
+    bool clear = 1;
+}