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 , entity_updates_skipped(0)
 184 , player_update_state()
 185 , player_update_pack(0)
 186 , player_update_timer(1500)
 187 , old_actions(0)
 188 , transmitter(*this)
 189 , chunk_queue()
 190 , old_base() {
 191         conn.SetHandler(this);
 192 }
 193
 194 ClientConnection::~ClientConnection() {
 195         DetachPlayer();
 196 }
 197
 198 void ClientConnection::Update(int dt) {
 199         conn.Update(dt);
 200         if (Disconnected()) {
 201                 return;
 202         }
 203         if (HasPlayer()) {
 204                 // sync entities
 205                 auto global_iter = server.GetWorld().Entities().begin();
 206                 auto global_end = server.GetWorld().Entities().end();
 207                 auto local_iter = spawns.begin();
 208                 auto local_end = spawns.end();
 209
 210                 while (global_iter != global_end && local_iter != local_end) {
 211                         if (global_iter->ID() == local_iter->entity->ID()) {
 212                                 // they're the same
 213                                 if (CanDespawn(*global_iter)) {
 214                                         SendDespawn(*local_iter);
 215                                 } else if (SendingUpdates()) {
 216                                         // update
 217                                         QueueUpdate(*local_iter);
 218                                 }
 219                                 ++global_iter;
 220                                 ++local_iter;
 221                         } else if (global_iter->ID() < local_iter->entity->ID()) {
 222                                 // global entity was inserted
 223                                 if (CanSpawn(*global_iter)) {
 224                                         auto spawned = spawns.emplace(local_iter, *global_iter);
 225                                         SendSpawn(*spawned);
 226                                 }
 227                                 ++global_iter;
 228                         } else {
 229                                 // global entity was removed
 230                                 SendDespawn(*local_iter);
 231                                 ++local_iter;
 232                         }
 233                 }
 234
 235                 // leftover spawns
 236                 while (global_iter != global_end) {
 237                         if (CanSpawn(*global_iter)) {
 238                                 spawns.emplace_back(*global_iter);
 239                                 SendSpawn(spawns.back());
 240                         }
 241                         ++global_iter;
 242                 }
 243
 244                 // leftover despawns
 245                 while (local_iter != local_end) {
 246                         SendDespawn(*local_iter);
 247                         ++local_iter;
 248                 }
 249                 SendUpdates();
 250
 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 bool ClientConnection::SendingUpdates() const noexcept {
 313         return entity_updates_skipped >= NetStat().SuggestedPacketSkip();
 314 }
 315
 316 void ClientConnection::QueueUpdate(SpawnStatus &status) {
 317         // don't send updates while spawn not ack'd or despawn sent
 318         if (status.spawn_pack == -1 && status.despawn_pack == -1) {
 319                 entity_updates.push_back(&status);
 320         }
 321 }
 322
 323 void ClientConnection::SendUpdates() {
 324         if (!SendingUpdates()) {
 325                 entity_updates.clear();
 326                 ++entity_updates_skipped;
 327                 return;
 328         }
 329         auto base = PlayerChunks().Base();
 330         auto pack = Prepare<Packet::EntityUpdate>();
 331         pack.WriteChunkBase(base);
 332         int entity_pos = 0;
 333         for (SpawnStatus *status : entity_updates) {
 334                 pack.WriteEntity(*status->entity, base, entity_pos);
 335                 ++entity_pos;
 336                 if (entity_pos == Packet::EntityUpdate::MAX_ENTITIES) {
 337                         pack.WriteEntityCount(entity_pos);
 338                         Send(Packet::EntityUpdate::GetSize(entity_pos));
 339                         pack = Prepare<Packet::EntityUpdate>();
 340                         entity_pos = 0;
 341                 }
 342         }
 343         if (entity_pos > 0) {
 344                 pack.WriteEntityCount(entity_pos);
 345                 Send(Packet::EntityUpdate::GetSize(entity_pos));
 346         }
 347         entity_updates.clear();
 348         entity_updates_skipped = 0;
 349 }
 350
 351 void ClientConnection::CheckPlayerFix() {
 352         // player_update_state's position holds the client's most recent prediction
 353         glm::vec3 diff = player_update_state.Diff(PlayerEntity().GetState());
 354         float dist_squared = dot(diff, diff);
 355
 356         // if client's prediction is off by more than 1cm, send
 357         // our (authoritative) state back so it can fix it
 358         constexpr float fix_thresh = 0.0001f;
 359
 360         if (dist_squared > fix_thresh) {
 361                 auto pack = Prepare<Packet::PlayerCorrection>();
 362                 pack.WritePacketSeq(player_update_pack);
 363                 pack.WritePlayer(PlayerEntity());
 364                 Send();
 365         }
 366 }
 367
 368 namespace {
 369
 370 struct QueueCompare {
 371         explicit QueueCompare(const glm::ivec3 &base)
 372         : base(base) { }
 373         bool operator ()(const glm::ivec3 &left, const glm::ivec3 &right) const noexcept {
 374                 const glm::ivec3 ld(left - base);
 375                 const glm::ivec3 rd(right - base);
 376                 return
 377                         ld.x * ld.x + ld.y * ld.y + ld.z * ld.z <
 378                         rd.x * rd.x + rd.y * rd.y + rd.z * rd.z;
 379         }
 380         const glm::ivec3 &base;
 381 };
 382
 383 }
 384
 385 void ClientConnection::CheckChunkQueue() {
 386         if (PlayerChunks().Base() != old_base) {
 387                 Chunk::Pos begin = PlayerChunks().CoordsBegin();
 388                 Chunk::Pos end = PlayerChunks().CoordsEnd();
 389                 for (Chunk::Pos pos = begin; pos.z < end.z; ++pos.z) {
 390                         for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 391                                 for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 392                                         if (manhattan_radius(pos - old_base) > PlayerChunks().Extent()) {
 393                                                 chunk_queue.push_back(pos);
 394                                         }
 395                                 }
 396                         }
 397                 }
 398                 old_base = PlayerChunks().Base();
 399                 sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 400         }
 401         if (transmitter.Transmitting()) {
 402                 transmitter.Transmit();
 403                 return;
 404         }
 405         if (transmitter.Idle()) {
 406                 int count = 0;
 407                 constexpr int max = 64;
 408                 while (count < max && !chunk_queue.empty()) {
 409                         Chunk::Pos pos = chunk_queue.front();
 410                         chunk_queue.pop_front();
 411                         if (PlayerChunks().InRange(pos)) {
 412                                 Chunk *chunk = PlayerChunks().Get(pos);
 413                                 if (chunk) {
 414                                         transmitter.Send(*chunk);
 415                                         return;
 416                                 } else {
 417                                         chunk_queue.push_back(pos);
 418                                 }
 419                                 ++count;
 420                         }
 421                 }
 422         }
 423 }
 424
 425 void ClientConnection::AttachPlayer(Player &player) {
 426         DetachPlayer();
 427         input.reset(new DirectInput(server.GetWorld(), player, server));
 428         PlayerEntity().Ref();
 429
 430         old_base = PlayerChunks().Base();
 431         Chunk::Pos begin = PlayerChunks().CoordsBegin();
 432         Chunk::Pos end = PlayerChunks().CoordsEnd();
 433         for (Chunk::Pos pos = begin; pos.z < end.z; ++pos.z) {
 434                 for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 435                         for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 436                                 chunk_queue.push_back(pos);
 437                         }
 438                 }
 439         }
 440         sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 441         // TODO: should the server do this?
 442         if (HasPlayerModel()) {
 443                 GetPlayerModel().Instantiate(PlayerEntity().GetModel());
 444         }
 445
 446         string msg = "player \"" + player.Name() + "\" joined";
 447         cout << msg << endl;
 448         server.DistributeMessage(0, 0, msg);
 449 }
 450
 451 void ClientConnection::DetachPlayer() {
 452         if (!HasPlayer()) return;
 453         string msg = "player \"" + input->GetPlayer().Name() + "\" left";
 454         cout << msg << endl;
 455         server.DistributeMessage(0, 0, msg);
 456
 457         server.GetWorldSave().Write(input->GetPlayer());
 458         PlayerEntity().Kill();
 459         PlayerEntity().UnRef();
 460         input.reset();
 461         transmitter.Abort();
 462         chunk_queue.clear();
 463         old_actions = 0;
 464 }
 465
 466 void ClientConnection::SetPlayerModel(const Model &m) noexcept {
 467         player_model = &m;
 468         if (HasPlayer()) {
 469                 m.Instantiate(PlayerEntity().GetModel());
 470         }
 471 }
 472
 473 bool ClientConnection::HasPlayerModel() const noexcept {
 474         return player_model;
 475 }
 476
 477 const Model &ClientConnection::GetPlayerModel() const noexcept {
 478         return *player_model;
 479 }
 480
 481 void ClientConnection::OnPacketReceived(uint16_t seq) {
 482         if (transmitter.Waiting()) {
 483                 transmitter.Ack(seq);
 484         }
 485         if (!confirm_wait) return;
 486         for (auto iter = spawns.begin(), end = spawns.end(); iter != end; ++iter) {
 487                 if (seq == iter->spawn_pack) {
 488                         iter->spawn_pack = -1;
 489                         --confirm_wait;
 490                         return;
 491                 }
 492                 if (seq == iter->despawn_pack) {
 493                         spawns.erase(iter);
 494                         --confirm_wait;
 495                         return;
 496                 }
 497         }
 498 }
 499
 500 void ClientConnection::OnPacketLost(uint16_t seq) {
 501         if (transmitter.Waiting()) {
 502                 transmitter.Nack(seq);
 503         }
 504         if (!confirm_wait) return;
 505         for (SpawnStatus &status : spawns) {
 506                 if (seq == status.spawn_pack) {
 507                         status.spawn_pack = -1;
 508                         --confirm_wait;
 509                         SendSpawn(status);
 510                         return;
 511                 }
 512                 if (seq == status.despawn_pack) {
 513                         status.despawn_pack = -1;
 514                         --confirm_wait;
 515                         SendDespawn(status);
 516                         return;
 517                 }
 518         }
 519 }
 520
 521 void ClientConnection::On(const Packet::Login &pack) {
 522         string name;
 523         pack.ReadPlayerName(name);
 524
 525         Player *new_player = server.JoinPlayer(name);
 526
 527         if (new_player) {
 528                 // success!
 529                 AttachPlayer(*new_player);
 530                 cout << "accepted login from player \"" << name << '"' << endl;
 531                 auto response = Prepare<Packet::Join>();
 532                 response.WritePlayer(new_player->GetEntity());
 533                 response.WriteWorldName(server.GetWorld().Name());
 534                 Send();
 535                 // set up update tracking
 536                 player_update_state = new_player->GetEntity().GetState();
 537                 player_update_pack = pack.Seq();
 538                 player_update_timer.Reset();
 539                 player_update_timer.Start();
 540         } else {
 541                 // aw no :(
 542                 cout << "rejected login from player \"" << name << '"' << endl;
 543                 Prepare<Packet::Part>();
 544                 Send();
 545                 conn.Close();
 546         }
 547 }
 548
 549 void ClientConnection::On(const Packet::Part &) {
 550         conn.Close();
 551 }
 552
 553 void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 554         if (!HasPlayer()) return;
 555         int pack_diff = int16_t(pack.Seq()) - int16_t(player_update_pack);
 556         bool overdue = player_update_timer.HitOnce();
 557         player_update_timer.Reset();
 558         if (pack_diff <= 0 && !overdue) {
 559                 // drop old packets if we have a fairly recent state
 560                 return;
 561         }
 562         glm::vec3 movement(0.0f);
 563         uint8_t new_actions;
 564         uint8_t slot;
 565
 566         player_update_pack = pack.Seq();
 567         pack.ReadPredictedState(player_update_state);
 568         pack.ReadMovement(movement);
 569         pack.ReadActions(new_actions);
 570         pack.ReadSlot(slot);
 571
 572         input->SetMovement(movement);
 573         input->TurnHead(player_update_state.pitch - input->GetPitch(), player_update_state.yaw - input->GetYaw());
 574         input->SelectInventory(slot);
 575
 576         if ((new_actions & 0x01) && !(old_actions & 0x01)) {
 577                 input->StartPrimaryAction();
 578         } else if (!(new_actions & 0x01) && (old_actions & 0x01)) {
 579                 input->StopPrimaryAction();
 580         }
 581         if ((new_actions & 0x02) && !(old_actions & 0x02)) {
 582                 input->StartSecondaryAction();
 583         } else if (!(new_actions & 0x02) && (old_actions & 0x02)) {
 584                 input->StopSecondaryAction();
 585         }
 586         if ((new_actions & 0x04) && !(old_actions & 0x04)) {
 587                 input->StartTertiaryAction();
 588         } else if (!(new_actions & 0x04) && (old_actions & 0x04)) {
 589                 input->StopTertiaryAction();
 590         }
 591         old_actions = new_actions;
 592 }
 593
 594 bool ClientConnection::ChunkInRange(const glm::ivec3 &pos) const noexcept {
 595         return HasPlayer() && PlayerChunks().InRange(pos);
 596 }
 597
 598 void ClientConnection::On(const Packet::Message &pack) {
 599         uint8_t type;
 600         uint32_t ref;
 601         string msg;
 602         pack.ReadType(type);
 603         pack.ReadReferral(ref);
 604         pack.ReadMessage(msg);
 605
 606         if (type == 1 && HasPlayer()) {
 607                 server.DispatchMessage(input->GetPlayer(), msg);
 608         }
 609 }
 610
 611
 612 Server::Server(
 613         const Config::Network &conf,
 614         World &world,
 615         const World::Config &wc,
 616         const WorldSave &save)
 617 : serv_sock(nullptr)
 618 , serv_pack{ -1, nullptr, 0 }
 619 , clients()
 620 , world(world)
 621 , spawn_index(world.Chunks().MakeIndex(wc.spawn, 3))
 622 , save(save)
 623 , player_model(nullptr)
 624 , cli(world) {
 625         serv_sock = SDLNet_UDP_Open(conf.port);
 626         if (!serv_sock) {
 627                 throw NetError("SDLNet_UDP_Open");
 628         }
 629
 630         serv_pack.data = new Uint8[sizeof(Packet)];
 631         serv_pack.maxlen = sizeof(Packet);
 632 }
 633
 634 Server::~Server() {
 635         world.Chunks().UnregisterIndex(spawn_index);
 636         delete[] serv_pack.data;
 637         SDLNet_UDP_Close(serv_sock);
 638 }
 639
 640
 641 void Server::Handle() {
 642         int result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 643         while (result > 0) {
 644                 HandlePacket(serv_pack);
 645                 result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 646         }
 647         if (result == -1) {
 648                 // a boo boo happened
 649                 throw NetError("SDLNet_UDP_Recv");
 650         }
 651 }
 652
 653 void Server::HandlePacket(const UDPpacket &udp_pack) {
 654         if (udp_pack.len < int(sizeof(Packet::Header))) {
 655                 // packet too small, drop
 656                 return;
 657         }
 658         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 659         if (pack.header.tag != Packet::TAG) {
 660                 // mistagged packet, drop
 661                 return;
 662         }
 663
 664         ClientConnection &client = GetClient(udp_pack.address);
 665         client.GetConnection().Received(udp_pack);
 666 }
 667
 668 ClientConnection &Server::GetClient(const IPaddress &addr) {
 669         for (ClientConnection &client : clients) {
 670                 if (client.Matches(addr)) {
 671                         return client;
 672                 }
 673         }
 674         clients.emplace_back(*this, addr);
 675         if (HasPlayerModel()) {
 676                 clients.back().SetPlayerModel(GetPlayerModel());
 677         }
 678         return clients.back();
 679 }
 680
 681 void Server::Update(int dt) {
 682         for (list<ClientConnection>::iterator client(clients.begin()), end(clients.end()); client != end;) {
 683                 client->Update(dt);
 684                 if (client->Disconnected()) {
 685                         client = clients.erase(client);
 686                 } else {
 687                         ++client;
 688                 }
 689         }
 690 }
 691
 692 void Server::SetPlayerModel(const Model &m) noexcept {
 693         player_model = &m;
 694         for (ClientConnection &client : clients) {
 695                 client.SetPlayerModel(m);
 696         }
 697 }
 698
 699 bool Server::HasPlayerModel() const noexcept {
 700         return player_model;
 701 }
 702
 703 const Model &Server::GetPlayerModel() const noexcept {
 704         return *player_model;
 705 }
 706
 707 Player *Server::JoinPlayer(const string &name) {
 708         if (spawn_index.MissingChunks() > 0) {
 709                 return nullptr;
 710         }
 711         Player *player = world.AddPlayer(name);
 712         if (!player) {
 713                 return nullptr;
 714         }
 715         if (save.Exists(*player)) {
 716                 save.Read(*player);
 717         } else {
 718                 // TODO: spawn
 719         }
 720         return player;
 721 }
 722
 723 void Server::SetBlock(Chunk &chunk, int index, const Block &block) {
 724         chunk.SetBlock(index, block);
 725         // TODO: batch chunk changes
 726         auto pack = Packet::Make<Packet::BlockUpdate>(GetPacket());
 727         pack.WriteChunkCoords(chunk.Position());
 728         pack.WriteBlockCount(uint32_t(1));
 729         pack.WriteIndex(index, 0);
 730         pack.WriteBlock(chunk.BlockAt(index), 0);
 731         GetPacket().len = sizeof(Packet::Header) + Packet::BlockUpdate::GetSize(1);
 732         for (ClientConnection &client : clients) {
 733                 if (client.ChunkInRange(chunk.Position())) {
 734                         client.Send();
 735                 }
 736         }
 737 }
 738
 739 void Server::DispatchMessage(Player &player, const string &msg) {
 740         if (msg.empty()) {
 741                 return;
 742         }
 743         if (msg[0] == '/' && msg.size() > 1 && msg[1] != '/') {
 744                 cli.Execute(player, msg.substr(1));
 745         } else {
 746                 DistributeMessage(1, player.GetEntity().ID(), msg);
 747         }
 748 }
 749
 750 void Server::DistributeMessage(uint8_t type, uint32_t ref, const string &msg) {
 751         auto pack = Packet::Make<Packet::Message>(serv_pack);
 752         pack.WriteType(type);
 753         pack.WriteReferral(ref);
 754         pack.WriteMessage(msg);
 755         serv_pack.len = sizeof(Packet::Header) + Packet::Message::GetSize(msg);
 756         SendAll();
 757 }
 758
 759 void Server::SendAll() {
 760         for (ClientConnection &client : clients) {
 761                 client.GetConnection().Send(serv_pack, serv_sock);
 762         }
 763 }
 764
 765 }
 766 }