src/server/net.cpp

   1 #include "ClientConnection.hpp"
   2 #include "ChunkTransmitter.hpp"
   3 #include "Server.hpp"
   4
   5 #include "../app/init.hpp"
   6 #include "../io/WorldSave.hpp"
   7 #include "../model/Model.hpp"
   8 #include "../world/ChunkIndex.hpp"
   9 #include "../world/Entity.hpp"
  10 #include "../world/World.hpp"
  11
  12 #include <algorithm>
  13 #include <iostream>
  14 #include <zlib.h>
  15 #include <glm/gtx/io.hpp>
  16
  17 using namespace std;
  18
  19
  20 namespace blank {
  21 namespace server {
  22
  23 ChunkTransmitter::ChunkTransmitter(ClientConnection &conn)
  24 : conn(conn)
  25 , current(nullptr)
  26 , buffer_size(Chunk::BlockSize() + 10)
  27 , buffer(new uint8_t[buffer_size])
  28 , buffer_len(0)
  29 , packet_len(Packet::ChunkData::MAX_DATA_LEN)
  30 , cursor(0)
  31 , num_packets(0)
  32 , begin_packet(-1)
  33 , data_packets()
  34 , confirm_wait(0)
  35 , trans_id(0)
  36 , compressed(false) {
  37
  38 }
  39
  40 ChunkTransmitter::~ChunkTransmitter() {
  41         Abort();
  42 }
  43
  44 bool ChunkTransmitter::Idle() const noexcept {
  45         return !Transmitting() && !Waiting();
  46 }
  47
  48 bool ChunkTransmitter::Transmitting() const noexcept {
  49         return cursor < num_packets;
  50 }
  51
  52 void ChunkTransmitter::Transmit() {
  53         if (cursor < num_packets) {
  54                 SendData(cursor);
  55                 ++cursor;
  56         }
  57 }
  58
  59 bool ChunkTransmitter::Waiting() const noexcept {
  60         return confirm_wait > 0;
  61 }
  62
  63 void ChunkTransmitter::Ack(uint16_t seq) {
  64         if (!Waiting()) {
  65                 return;
  66         }
  67         if (seq == begin_packet) {
  68                 begin_packet = -1;
  69                 --confirm_wait;
  70                 if (Idle()) {
  71                         Release();
  72                 }
  73                 return;
  74         }
  75         for (int i = 0, end = data_packets.size(); i < end; ++i) {
  76                 if (seq == data_packets[i]) {
  77                         data_packets[i] = -1;
  78                         --confirm_wait;
  79                         if (Idle()) {
  80                                 Release();
  81                         }
  82                         return;
  83                 }
  84         }
  85 }
  86
  87 void ChunkTransmitter::Nack(uint16_t seq) {
  88         if (!Waiting()) {
  89                 return;
  90         }
  91         if (seq == begin_packet) {
  92                 SendBegin();
  93                 return;
  94         }
  95         for (size_t i = 0, end = data_packets.size(); i < end; ++i) {
  96                 if (seq == data_packets[i]) {
  97                         SendData(i);
  98                         return;
  99                 }
 100         }
 101 }
 102
 103 void ChunkTransmitter::Abort() {
 104         if (!current) return;
 105
 106         Release();
 107
 108         begin_packet = -1;
 109         data_packets.clear();
 110         confirm_wait = 0;
 111 }
 112
 113 void ChunkTransmitter::Send(Chunk &chunk) {
 114         // abort current chunk, if any
 115         Abort();
 116
 117         current = &chunk;
 118         current->Ref();
 119
 120         // load new chunk data
 121         compressed = true;
 122         buffer_len = buffer_size;
 123         if (compress(buffer.get(), &buffer_len, reinterpret_cast<const Bytef *>(chunk.BlockData()), Chunk::BlockSize()) != Z_OK) {
 124                 // compression failed, send it uncompressed
 125                 buffer_len = Chunk::BlockSize();
 126                 memcpy(buffer.get(), chunk.BlockData(), buffer_len);
 127                 compressed = false;
 128         }
 129         cursor = 0;
 130         num_packets = (buffer_len / packet_len) + (buffer_len % packet_len != 0);
 131         data_packets.resize(num_packets, -1);
 132
 133         ++trans_id;
 134         SendBegin();
 135 }
 136
 137 void ChunkTransmitter::SendBegin() {
 138         uint32_t flags = compressed;
 139         auto pack = conn.Prepare<Packet::ChunkBegin>();
 140         pack.WriteTransmissionId(trans_id);
 141         pack.WriteFlags(flags);
 142         pack.WriteChunkCoords(current->Position());
 143         pack.WriteDataSize(buffer_len);
 144         if (begin_packet == -1) {
 145                 ++confirm_wait;
 146         }
 147         begin_packet = conn.Send();
 148 }
 149
 150 void ChunkTransmitter::SendData(size_t i) {
 151         int pos = i * packet_len;
 152         int len = min(packet_len, buffer_len - pos);
 153         const uint8_t *data = &buffer[pos];
 154
 155         auto pack = conn.Prepare<Packet::ChunkData>();
 156         pack.WriteTransmissionId(trans_id);
 157         pack.WriteDataOffset(pos);
 158         pack.WriteDataSize(len);
 159         pack.WriteData(data, len);
 160
 161         if (data_packets[i] == -1) {
 162                 ++confirm_wait;
 163         }
 164         data_packets[i] = conn.Send();
 165 }
 166
 167 void ChunkTransmitter::Release() {
 168         if (current) {
 169                 current->UnRef();
 170                 current = nullptr;
 171         }
 172 }
 173
 174
 175 ClientConnection::ClientConnection(Server &server, const IPaddress &addr)
 176 : server(server)
 177 , conn(addr)
 178 , input()
 179 , player_model(nullptr)
 180 , spawns()
 181 , confirm_wait(0)
 182 , entity_updates()
 183 , player_update_state()
 184 , player_update_pack(0)
 185 , player_update_timer(1500)
 186 , old_actions(0)
 187 , transmitter(*this)
 188 , chunk_queue()
 189 , old_base() {
 190         conn.SetHandler(this);
 191 }
 192
 193 ClientConnection::~ClientConnection() {
 194         DetachPlayer();
 195 }
 196
 197 void ClientConnection::Update(int dt) {
 198         conn.Update(dt);
 199         if (Disconnected()) {
 200                 return;
 201         }
 202         if (HasPlayer()) {
 203                 // sync entities
 204                 auto global_iter = server.GetWorld().Entities().begin();
 205                 auto global_end = server.GetWorld().Entities().end();
 206                 auto local_iter = spawns.begin();
 207                 auto local_end = spawns.end();
 208
 209                 while (global_iter != global_end && local_iter != local_end) {
 210                         if (global_iter->ID() == local_iter->entity->ID()) {
 211                                 // they're the same
 212                                 if (CanDespawn(*global_iter)) {
 213                                         SendDespawn(*local_iter);
 214                                 } else {
 215                                         // update
 216                                         QueueUpdate(*local_iter);
 217                                 }
 218                                 ++global_iter;
 219                                 ++local_iter;
 220                         } else if (global_iter->ID() < local_iter->entity->ID()) {
 221                                 // global entity was inserted
 222                                 if (CanSpawn(*global_iter)) {
 223                                         auto spawned = spawns.emplace(local_iter, *global_iter);
 224                                         SendSpawn(*spawned);
 225                                 }
 226                                 ++global_iter;
 227                         } else {
 228                                 // global entity was removed
 229                                 SendDespawn(*local_iter);
 230                                 ++local_iter;
 231                         }
 232                 }
 233
 234                 // leftover spawns
 235                 while (global_iter != global_end) {
 236                         if (CanSpawn(*global_iter)) {
 237                                 spawns.emplace_back(*global_iter);
 238                                 SendSpawn(spawns.back());
 239                         }
 240                         ++global_iter;
 241                 }
 242
 243                 // leftover despawns
 244                 while (local_iter != local_end) {
 245                         SendDespawn(*local_iter);
 246                         ++local_iter;
 247                 }
 248                 SendUpdates();
 249
 250                 input->Update(dt);
 251                 CheckPlayerFix();
 252                 CheckChunkQueue();
 253         }
 254         if (conn.ShouldPing()) {
 255                 conn.SendPing(server.GetPacket(), server.GetSocket());
 256         }
 257 }
 258
 259 ClientConnection::SpawnStatus::SpawnStatus(Entity &e)
 260 : entity(&e)
 261 , spawn_pack(-1)
 262 , despawn_pack(-1) {
 263         entity->Ref();
 264 }
 265
 266 ClientConnection::SpawnStatus::~SpawnStatus() {
 267         entity->UnRef();
 268 }
 269
 270 bool ClientConnection::CanSpawn(const Entity &e) const noexcept {
 271         return
 272                 &e != &PlayerEntity() &&
 273                 !e.Dead() &&
 274                 manhattan_radius(e.ChunkCoords() - PlayerEntity().ChunkCoords()) < 7;
 275 }
 276
 277 bool ClientConnection::CanDespawn(const Entity &e) const noexcept {
 278         return
 279                 e.Dead() ||
 280                 manhattan_radius(e.ChunkCoords() - PlayerEntity().ChunkCoords()) > 7;
 281 }
 282
 283 uint16_t ClientConnection::Send() {
 284         return conn.Send(server.GetPacket(), server.GetSocket());
 285 }
 286
 287 uint16_t ClientConnection::Send(size_t len) {
 288         server.GetPacket().len = sizeof(Packet::Header) + len;
 289         return Send();
 290 }
 291
 292 void ClientConnection::SendSpawn(SpawnStatus &status) {
 293         // don't double spawn
 294         if (status.spawn_pack != -1) return;
 295
 296         auto pack = Prepare<Packet::SpawnEntity>();
 297         pack.WriteEntity(*status.entity);
 298         status.spawn_pack = Send();
 299         ++confirm_wait;
 300 }
 301
 302 void ClientConnection::SendDespawn(SpawnStatus &status) {
 303         // don't double despawn
 304         if (status.despawn_pack != -1) return;
 305
 306         auto pack = Prepare<Packet::DespawnEntity>();
 307         pack.WriteEntityID(status.entity->ID());
 308         status.despawn_pack = Send();
 309         ++confirm_wait;
 310 }
 311
 312 void ClientConnection::QueueUpdate(SpawnStatus &status) {
 313         // don't send updates while spawn not ack'd or despawn sent
 314         if (status.spawn_pack == -1 && status.despawn_pack == -1) {
 315                 entity_updates.push_back(&status);
 316         }
 317 }
 318
 319 void ClientConnection::SendUpdates() {
 320         auto pack = Prepare<Packet::EntityUpdate>();
 321         int entity_pos = 0;
 322         for (SpawnStatus *status : entity_updates) {
 323                 pack.WriteEntity(*status->entity, entity_pos);
 324                 ++entity_pos;
 325                 if (entity_pos == Packet::EntityUpdate::MAX_ENTITIES) {
 326                         pack.WriteEntityCount(entity_pos);
 327                         Send(Packet::EntityUpdate::GetSize(entity_pos));
 328                         pack = Prepare<Packet::EntityUpdate>();
 329                         entity_pos = 0;
 330                 }
 331         }
 332         if (entity_pos > 0) {
 333                 pack.WriteEntityCount(entity_pos);
 334                 Send(Packet::EntityUpdate::GetSize(entity_pos));
 335         }
 336         entity_updates.clear();
 337 }
 338
 339 void ClientConnection::CheckPlayerFix() {
 340         // player_update_state's position holds the client's most recent prediction
 341         glm::vec3 diff = player_update_state.Diff(PlayerEntity().GetState());
 342         float dist_squared = dot(diff, diff);
 343
 344         // if client's prediction is off by more than 1cm, send
 345         // our (authoritative) state back so it can fix it
 346         constexpr float fix_thresh = 0.0001f;
 347
 348         if (dist_squared > fix_thresh) {
 349                 auto pack = Prepare<Packet::PlayerCorrection>();
 350                 pack.WritePacketSeq(player_update_pack);
 351                 pack.WritePlayer(PlayerEntity());
 352                 Send();
 353         }
 354 }
 355
 356 namespace {
 357
 358 struct QueueCompare {
 359         explicit QueueCompare(const glm::ivec3 &base)
 360         : base(base) { }
 361         bool operator ()(const glm::ivec3 &left, const glm::ivec3 &right) const noexcept {
 362                 const glm::ivec3 ld(left - base);
 363                 const glm::ivec3 rd(right - base);
 364                 return
 365                         ld.x * ld.x + ld.y * ld.y + ld.z * ld.z <
 366                         rd.x * rd.x + rd.y * rd.y + rd.z * rd.z;
 367         }
 368         const glm::ivec3 &base;
 369 };
 370
 371 }
 372
 373 void ClientConnection::CheckChunkQueue() {
 374         if (PlayerChunks().Base() != old_base) {
 375                 Chunk::Pos begin = PlayerChunks().CoordsBegin();
 376                 Chunk::Pos end = PlayerChunks().CoordsEnd();
 377                 for (Chunk::Pos pos = begin; pos.z < end.z; ++pos.z) {
 378                         for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 379                                 for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 380                                         if (manhattan_radius(pos - old_base) > PlayerChunks().Extent()) {
 381                                                 chunk_queue.push_back(pos);
 382                                         }
 383                                 }
 384                         }
 385                 }
 386                 old_base = PlayerChunks().Base();
 387                 sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 388         }
 389         if (transmitter.Transmitting()) {
 390                 transmitter.Transmit();
 391                 return;
 392         }
 393         if (transmitter.Idle()) {
 394                 int count = 0;
 395                 constexpr int max = 64;
 396                 while (count < max && !chunk_queue.empty()) {
 397                         Chunk::Pos pos = chunk_queue.front();
 398                         chunk_queue.pop_front();
 399                         if (PlayerChunks().InRange(pos)) {
 400                                 Chunk *chunk = PlayerChunks().Get(pos);
 401                                 if (chunk) {
 402                                         transmitter.Send(*chunk);
 403                                         return;
 404                                 } else {
 405                                         chunk_queue.push_back(pos);
 406                                 }
 407                                 ++count;
 408                         }
 409                 }
 410         }
 411 }
 412
 413 void ClientConnection::AttachPlayer(Player &player) {
 414         DetachPlayer();
 415         input.reset(new DirectInput(server.GetWorld(), player, server));
 416         PlayerEntity().Ref();
 417
 418         old_base = PlayerChunks().Base();
 419         Chunk::Pos begin = PlayerChunks().CoordsBegin();
 420         Chunk::Pos end = PlayerChunks().CoordsEnd();
 421         for (Chunk::Pos pos = begin; pos.z < end.z; ++pos.z) {
 422                 for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 423                         for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 424                                 chunk_queue.push_back(pos);
 425                         }
 426                 }
 427         }
 428         sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 429         // TODO: should the server do this?
 430         if (HasPlayerModel()) {
 431                 GetPlayerModel().Instantiate(PlayerEntity().GetModel());
 432         }
 433
 434         cout << "player \"" << player.Name() << "\" joined" << endl;
 435 }
 436
 437 void ClientConnection::DetachPlayer() {
 438         if (!HasPlayer()) return;
 439         cout << "player \"" << input->GetPlayer().Name() << "\" left" << endl;
 440         server.GetWorldSave().Write(input->GetPlayer());
 441         PlayerEntity().Kill();
 442         PlayerEntity().UnRef();
 443         input.reset();
 444         transmitter.Abort();
 445         chunk_queue.clear();
 446         old_actions = 0;
 447 }
 448
 449 void ClientConnection::SetPlayerModel(const Model &m) noexcept {
 450         player_model = &m;
 451         if (HasPlayer()) {
 452                 m.Instantiate(PlayerEntity().GetModel());
 453         }
 454 }
 455
 456 bool ClientConnection::HasPlayerModel() const noexcept {
 457         return player_model;
 458 }
 459
 460 const Model &ClientConnection::GetPlayerModel() const noexcept {
 461         return *player_model;
 462 }
 463
 464 void ClientConnection::OnPacketReceived(uint16_t seq) {
 465         if (transmitter.Waiting()) {
 466                 transmitter.Ack(seq);
 467         }
 468         if (!confirm_wait) return;
 469         for (auto iter = spawns.begin(), end = spawns.end(); iter != end; ++iter) {
 470                 if (seq == iter->spawn_pack) {
 471                         iter->spawn_pack = -1;
 472                         --confirm_wait;
 473                         return;
 474                 }
 475                 if (seq == iter->despawn_pack) {
 476                         spawns.erase(iter);
 477                         --confirm_wait;
 478                         return;
 479                 }
 480         }
 481 }
 482
 483 void ClientConnection::OnPacketLost(uint16_t seq) {
 484         if (transmitter.Waiting()) {
 485                 transmitter.Nack(seq);
 486         }
 487         if (!confirm_wait) return;
 488         for (SpawnStatus &status : spawns) {
 489                 if (seq == status.spawn_pack) {
 490                         status.spawn_pack = -1;
 491                         --confirm_wait;
 492                         SendSpawn(status);
 493                         return;
 494                 }
 495                 if (seq == status.despawn_pack) {
 496                         status.despawn_pack = -1;
 497                         --confirm_wait;
 498                         SendDespawn(status);
 499                         return;
 500                 }
 501         }
 502 }
 503
 504 void ClientConnection::On(const Packet::Login &pack) {
 505         string name;
 506         pack.ReadPlayerName(name);
 507
 508         Player *new_player = server.JoinPlayer(name);
 509
 510         if (new_player) {
 511                 // success!
 512                 AttachPlayer(*new_player);
 513                 cout << "accepted login from player \"" << name << '"' << endl;
 514                 auto response = Prepare<Packet::Join>();
 515                 response.WritePlayer(new_player->GetEntity());
 516                 response.WriteWorldName(server.GetWorld().Name());
 517                 Send();
 518                 // set up update tracking
 519                 player_update_state = new_player->GetEntity().GetState();
 520                 player_update_pack = pack.Seq();
 521                 player_update_timer.Reset();
 522                 player_update_timer.Start();
 523         } else {
 524                 // aw no :(
 525                 cout << "rejected login from player \"" << name << '"' << endl;
 526                 Prepare<Packet::Part>();
 527                 Send();
 528                 conn.Close();
 529         }
 530 }
 531
 532 void ClientConnection::On(const Packet::Part &) {
 533         conn.Close();
 534 }
 535
 536 void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 537         if (!HasPlayer()) return;
 538         int pack_diff = int16_t(pack.Seq()) - int16_t(player_update_pack);
 539         bool overdue = player_update_timer.HitOnce();
 540         player_update_timer.Reset();
 541         if (pack_diff <= 0 && !overdue) {
 542                 // drop old packets if we have a fairly recent state
 543                 return;
 544         }
 545         glm::vec3 movement(0.0f);
 546         float pitch = 0.0f;
 547         float yaw = 0.0f;
 548         uint8_t new_actions;
 549         uint8_t slot;
 550
 551         player_update_pack = pack.Seq();
 552         pack.ReadPredictedState(player_update_state);
 553         pack.ReadMovement(movement);
 554         pack.ReadPitch(pitch);
 555         pack.ReadYaw(yaw);
 556         pack.ReadActions(new_actions);
 557         pack.ReadSlot(slot);
 558
 559         input->SetMovement(movement);
 560         input->TurnHead(pitch - input->GetPitch(), yaw - input->GetYaw());
 561         input->SelectInventory(slot);
 562
 563         if ((new_actions & 0x01) && !(old_actions & 0x01)) {
 564                 input->StartPrimaryAction();
 565         } else if (!(new_actions & 0x01) && (old_actions & 0x01)) {
 566                 input->StopPrimaryAction();
 567         }
 568         if ((new_actions & 0x02) && !(old_actions & 0x02)) {
 569                 input->StartSecondaryAction();
 570         } else if (!(new_actions & 0x02) && (old_actions & 0x02)) {
 571                 input->StopSecondaryAction();
 572         }
 573         if ((new_actions & 0x04) && !(old_actions & 0x04)) {
 574                 input->StartTertiaryAction();
 575         } else if (!(new_actions & 0x04) && (old_actions & 0x04)) {
 576                 input->StopTertiaryAction();
 577         }
 578         old_actions = new_actions;
 579 }
 580
 581 bool ClientConnection::ChunkInRange(const glm::ivec3 &pos) const noexcept {
 582         return HasPlayer() && PlayerChunks().InRange(pos);
 583 }
 584
 585 void ClientConnection::On(const Packet::Message &pack) {
 586         uint8_t type;
 587         uint32_t ref;
 588         string msg;
 589         pack.ReadType(type);
 590         pack.ReadReferral(ref);
 591         pack.ReadMessage(msg);
 592
 593         if (type == 1 && HasPlayer()) {
 594                 server.DistributeMessage(1, PlayerEntity().ID(), msg);
 595         }
 596 }
 597
 598
 599 Server::Server(
 600         const Config::Network &conf,
 601         World &world,
 602         const World::Config &wc,
 603         const WorldSave &save)
 604 : serv_sock(nullptr)
 605 , serv_pack{ -1, nullptr, 0 }
 606 , clients()
 607 , world(world)
 608 , spawn_index(world.Chunks().MakeIndex(wc.spawn, 3))
 609 , save(save)
 610 , player_model(nullptr) {
 611         serv_sock = SDLNet_UDP_Open(conf.port);
 612         if (!serv_sock) {
 613                 throw NetError("SDLNet_UDP_Open");
 614         }
 615
 616         serv_pack.data = new Uint8[sizeof(Packet)];
 617         serv_pack.maxlen = sizeof(Packet);
 618 }
 619
 620 Server::~Server() {
 621         world.Chunks().UnregisterIndex(spawn_index);
 622         delete[] serv_pack.data;
 623         SDLNet_UDP_Close(serv_sock);
 624 }
 625
 626
 627 void Server::Handle() {
 628         int result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 629         while (result > 0) {
 630                 HandlePacket(serv_pack);
 631                 result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 632         }
 633         if (result == -1) {
 634                 // a boo boo happened
 635                 throw NetError("SDLNet_UDP_Recv");
 636         }
 637 }
 638
 639 void Server::HandlePacket(const UDPpacket &udp_pack) {
 640         if (udp_pack.len < int(sizeof(Packet::Header))) {
 641                 // packet too small, drop
 642                 return;
 643         }
 644         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 645         if (pack.header.tag != Packet::TAG) {
 646                 // mistagged packet, drop
 647                 return;
 648         }
 649
 650         ClientConnection &client = GetClient(udp_pack.address);
 651         client.GetConnection().Received(udp_pack);
 652 }
 653
 654 ClientConnection &Server::GetClient(const IPaddress &addr) {
 655         for (ClientConnection &client : clients) {
 656                 if (client.Matches(addr)) {
 657                         return client;
 658                 }
 659         }
 660         clients.emplace_back(*this, addr);
 661         if (HasPlayerModel()) {
 662                 clients.back().SetPlayerModel(GetPlayerModel());
 663         }
 664         return clients.back();
 665 }
 666
 667 void Server::Update(int dt) {
 668         for (list<ClientConnection>::iterator client(clients.begin()), end(clients.end()); client != end;) {
 669                 client->Update(dt);
 670                 if (client->Disconnected()) {
 671                         client = clients.erase(client);
 672                 } else {
 673                         ++client;
 674                 }
 675         }
 676 }
 677
 678 void Server::SetPlayerModel(const Model &m) noexcept {
 679         player_model = &m;
 680         for (ClientConnection &client : clients) {
 681                 client.SetPlayerModel(m);
 682         }
 683 }
 684
 685 bool Server::HasPlayerModel() const noexcept {
 686         return player_model;
 687 }
 688
 689 const Model &Server::GetPlayerModel() const noexcept {
 690         return *player_model;
 691 }
 692
 693 Player *Server::JoinPlayer(const string &name) {
 694         if (spawn_index.MissingChunks() > 0) {
 695                 return nullptr;
 696         }
 697         Player *player = world.AddPlayer(name);
 698         if (!player) {
 699                 return nullptr;
 700         }
 701         if (save.Exists(*player)) {
 702                 save.Read(*player);
 703         } else {
 704                 // TODO: spawn
 705         }
 706         return player;
 707 }
 708
 709 void Server::SetBlock(Chunk &chunk, int index, const Block &block) {
 710         chunk.SetBlock(index, block);
 711         // TODO: batch chunk changes
 712         auto pack = Packet::Make<Packet::BlockUpdate>(GetPacket());
 713         pack.WriteChunkCoords(chunk.Position());
 714         pack.WriteBlockCount(uint32_t(1));
 715         pack.WriteIndex(index, 0);
 716         pack.WriteBlock(chunk.BlockAt(index), 0);
 717         GetPacket().len = sizeof(Packet::Header) + Packet::BlockUpdate::GetSize(1);
 718         for (ClientConnection &client : clients) {
 719                 if (client.ChunkInRange(chunk.Position())) {
 720                         client.Send();
 721                 }
 722         }
 723 }
 724
 725 void Server::DistributeMessage(uint8_t type, uint32_t ref, const string &msg) {
 726         auto pack = Packet::Make<Packet::Message>(serv_pack);
 727         pack.WriteType(type);
 728         pack.WriteReferral(ref);
 729         pack.WriteMessage(msg);
 730         serv_pack.len = sizeof(Packet::Header) + Packet::Message::GetSize(msg);
 731         SendAll();
 732 }
 733
 734 void Server::SendAll() {
 735         for (ClientConnection &client : clients) {
 736                 client.GetConnection().Send(serv_pack, serv_sock);
 737         }
 738 }
 739
 740 }
 741 }