src/server/net.cpp

   1 #include "ClientConnection.hpp"
   2 #include "ChunkTransmitter.hpp"
   3 #include "Server.hpp"
   4
   5 #include "../app/init.hpp"
   6 #include "../geometry/distance.hpp"
   7 #include "../io/WorldSave.hpp"
   8 #include "../model/Model.hpp"
   9 #include "../world/ChunkIndex.hpp"
  10 #include "../world/Entity.hpp"
  11 #include "../world/World.hpp"
  12
  13 #include <algorithm>
  14 #include <iostream>
  15 #include <zlib.h>
  16 #include <glm/gtx/io.hpp>
  17
  18 using namespace std;
  19
  20
  21 namespace blank {
  22 namespace server {
  23
  24 ChunkTransmitter::ChunkTransmitter(ClientConnection &conn)
  25 : conn(conn)
  26 , current(nullptr)
  27 , buffer_size(Chunk::BlockSize() + 10)
  28 , buffer(new uint8_t[buffer_size])
  29 , buffer_len(0)
  30 , packet_len(Packet::ChunkData::MAX_DATA_LEN)
  31 , cursor(0)
  32 , num_packets(0)
  33 , begin_packet(-1)
  34 , data_packets()
  35 , confirm_wait(0)
  36 , trans_id(0)
  37 , compressed(false) {
  38
  39 }
  40
  41 ChunkTransmitter::~ChunkTransmitter() {
  42         Abort();
  43 }
  44
  45 bool ChunkTransmitter::Idle() const noexcept {
  46         return !Transmitting() && !Waiting();
  47 }
  48
  49 bool ChunkTransmitter::Transmitting() const noexcept {
  50         return cursor < num_packets;
  51 }
  52
  53 void ChunkTransmitter::Transmit() {
  54         if (cursor < num_packets) {
  55                 SendData(cursor);
  56                 ++cursor;
  57         }
  58 }
  59
  60 bool ChunkTransmitter::Waiting() const noexcept {
  61         return confirm_wait > 0;
  62 }
  63
  64 void ChunkTransmitter::Ack(uint16_t seq) {
  65         if (!Waiting()) {
  66                 return;
  67         }
  68         if (seq == begin_packet) {
  69                 begin_packet = -1;
  70                 --confirm_wait;
  71                 if (Idle()) {
  72                         Release();
  73                 }
  74                 return;
  75         }
  76         for (int i = 0, end = data_packets.size(); i < end; ++i) {
  77                 if (seq == data_packets[i]) {
  78                         data_packets[i] = -1;
  79                         --confirm_wait;
  80                         if (Idle()) {
  81                                 Release();
  82                         }
  83                         return;
  84                 }
  85         }
  86 }
  87
  88 void ChunkTransmitter::Nack(uint16_t seq) {
  89         if (!Waiting()) {
  90                 return;
  91         }
  92         if (seq == begin_packet) {
  93                 SendBegin();
  94                 return;
  95         }
  96         for (size_t i = 0, end = data_packets.size(); i < end; ++i) {
  97                 if (seq == data_packets[i]) {
  98                         SendData(i);
  99                         return;
 100                 }
 101         }
 102 }
 103
 104 void ChunkTransmitter::Abort() {
 105         if (!current) return;
 106
 107         Release();
 108
 109         begin_packet = -1;
 110         data_packets.clear();
 111         confirm_wait = 0;
 112 }
 113
 114 void ChunkTransmitter::Send(Chunk &chunk) {
 115         // abort current chunk, if any
 116         Abort();
 117
 118         current = &chunk;
 119         current->Ref();
 120
 121         // load new chunk data
 122         compressed = true;
 123         buffer_len = buffer_size;
 124         if (compress(buffer.get(), &buffer_len, reinterpret_cast<const Bytef *>(chunk.BlockData()), Chunk::BlockSize()) != Z_OK) {
 125                 // compression failed, send it uncompressed
 126                 buffer_len = Chunk::BlockSize();
 127                 memcpy(buffer.get(), chunk.BlockData(), buffer_len);
 128                 compressed = false;
 129         }
 130         cursor = 0;
 131         num_packets = (buffer_len / packet_len) + (buffer_len % packet_len != 0);
 132         data_packets.resize(num_packets, -1);
 133
 134         ++trans_id;
 135         SendBegin();
 136 }
 137
 138 void ChunkTransmitter::SendBegin() {
 139         uint32_t flags = compressed;
 140         auto pack = conn.Prepare<Packet::ChunkBegin>();
 141         pack.WriteTransmissionId(trans_id);
 142         pack.WriteFlags(flags);
 143         pack.WriteChunkCoords(current->Position());
 144         pack.WriteDataSize(buffer_len);
 145         if (begin_packet == -1) {
 146                 ++confirm_wait;
 147         }
 148         begin_packet = conn.Send();
 149 }
 150
 151 void ChunkTransmitter::SendData(size_t i) {
 152         int pos = i * packet_len;
 153         int len = min(packet_len, buffer_len - pos);
 154         const uint8_t *data = &buffer[pos];
 155
 156         auto pack = conn.Prepare<Packet::ChunkData>();
 157         pack.WriteTransmissionId(trans_id);
 158         pack.WriteDataOffset(pos);
 159         pack.WriteDataSize(len);
 160         pack.WriteData(data, len);
 161
 162         if (data_packets[i] == -1) {
 163                 ++confirm_wait;
 164         }
 165         data_packets[i] = conn.Send();
 166 }
 167
 168 void ChunkTransmitter::Release() {
 169         if (current) {
 170                 current->UnRef();
 171                 current = nullptr;
 172         }
 173 }
 174
 175
 176 ClientConnection::ClientConnection(Server &server, const IPaddress &addr)
 177 : server(server)
 178 , conn(addr)
 179 , input()
 180 , player_model(nullptr)
 181 , spawns()
 182 , confirm_wait(0)
 183 , entity_updates()
 184 , entity_updates_skipped(0)
 185 , player_update_state()
 186 , player_update_pack(0)
 187 , player_update_timer(1500)
 188 , old_actions(0)
 189 , transmitter(*this)
 190 , chunk_queue()
 191 , old_base() {
 192         conn.SetHandler(this);
 193 }
 194
 195 ClientConnection::~ClientConnection() {
 196         DetachPlayer();
 197 }
 198
 199 void ClientConnection::Update(int dt) {
 200         conn.Update(dt);
 201         if (Disconnected()) {
 202                 return;
 203         }
 204         if (HasPlayer()) {
 205                 // sync entities
 206                 auto global_iter = server.GetWorld().Entities().begin();
 207                 auto global_end = server.GetWorld().Entities().end();
 208                 auto local_iter = spawns.begin();
 209                 auto local_end = spawns.end();
 210
 211                 while (global_iter != global_end && local_iter != local_end) {
 212                         if (global_iter->ID() == local_iter->entity->ID()) {
 213                                 // they're the same
 214                                 if (CanDespawn(*global_iter)) {
 215                                         SendDespawn(*local_iter);
 216                                 } else if (SendingUpdates()) {
 217                                         // update
 218                                         QueueUpdate(*local_iter);
 219                                 }
 220                                 ++global_iter;
 221                                 ++local_iter;
 222                         } else if (global_iter->ID() < local_iter->entity->ID()) {
 223                                 // global entity was inserted
 224                                 if (CanSpawn(*global_iter)) {
 225                                         auto spawned = spawns.emplace(local_iter, *global_iter);
 226                                         SendSpawn(*spawned);
 227                                 }
 228                                 ++global_iter;
 229                         } else {
 230                                 // global entity was removed
 231                                 SendDespawn(*local_iter);
 232                                 ++local_iter;
 233                         }
 234                 }
 235
 236                 // leftover spawns
 237                 while (global_iter != global_end) {
 238                         if (CanSpawn(*global_iter)) {
 239                                 spawns.emplace_back(*global_iter);
 240                                 SendSpawn(spawns.back());
 241                         }
 242                         ++global_iter;
 243                 }
 244
 245                 // leftover despawns
 246                 while (local_iter != local_end) {
 247                         SendDespawn(*local_iter);
 248                         ++local_iter;
 249                 }
 250                 SendUpdates();
 251
 252                 CheckPlayerFix();
 253                 CheckChunkQueue();
 254         }
 255         if (conn.ShouldPing()) {
 256                 conn.SendPing(server.GetPacket(), server.GetSocket());
 257         }
 258 }
 259
 260 ClientConnection::SpawnStatus::SpawnStatus(Entity &e)
 261 : entity(&e)
 262 , spawn_pack(-1)
 263 , despawn_pack(-1) {
 264         entity->Ref();
 265 }
 266
 267 ClientConnection::SpawnStatus::~SpawnStatus() {
 268         entity->UnRef();
 269 }
 270
 271 bool ClientConnection::CanSpawn(const Entity &e) const noexcept {
 272         return
 273                 &e != &PlayerEntity() &&
 274                 !e.Dead() &&
 275                 manhattan_radius(e.ChunkCoords() - PlayerEntity().ChunkCoords()) < 7;
 276 }
 277
 278 bool ClientConnection::CanDespawn(const Entity &e) const noexcept {
 279         return
 280                 e.Dead() ||
 281                 manhattan_radius(e.ChunkCoords() - PlayerEntity().ChunkCoords()) > 7;
 282 }
 283
 284 uint16_t ClientConnection::Send() {
 285         return conn.Send(server.GetPacket(), server.GetSocket());
 286 }
 287
 288 uint16_t ClientConnection::Send(size_t len) {
 289         server.GetPacket().len = sizeof(Packet::Header) + len;
 290         return Send();
 291 }
 292
 293 void ClientConnection::SendSpawn(SpawnStatus &status) {
 294         // don't double spawn
 295         if (status.spawn_pack != -1) return;
 296
 297         auto pack = Prepare<Packet::SpawnEntity>();
 298         pack.WriteEntity(*status.entity);
 299         status.spawn_pack = Send();
 300         ++confirm_wait;
 301 }
 302
 303 void ClientConnection::SendDespawn(SpawnStatus &status) {
 304         // don't double despawn
 305         if (status.despawn_pack != -1) return;
 306
 307         auto pack = Prepare<Packet::DespawnEntity>();
 308         pack.WriteEntityID(status.entity->ID());
 309         status.despawn_pack = Send();
 310         ++confirm_wait;
 311 }
 312
 313 bool ClientConnection::SendingUpdates() const noexcept {
 314         return entity_updates_skipped >= NetStat().SuggestedPacketSkip();
 315 }
 316
 317 void ClientConnection::QueueUpdate(SpawnStatus &status) {
 318         // don't send updates while spawn not ack'd or despawn sent
 319         if (status.spawn_pack == -1 && status.despawn_pack == -1) {
 320                 entity_updates.push_back(&status);
 321         }
 322 }
 323
 324 void ClientConnection::SendUpdates() {
 325         if (!SendingUpdates()) {
 326                 entity_updates.clear();
 327                 ++entity_updates_skipped;
 328                 return;
 329         }
 330         auto base = PlayerChunks().Base();
 331         auto pack = Prepare<Packet::EntityUpdate>();
 332         pack.WriteChunkBase(base);
 333         int entity_pos = 0;
 334         for (SpawnStatus *status : entity_updates) {
 335                 pack.WriteEntity(*status->entity, base, entity_pos);
 336                 ++entity_pos;
 337                 if (entity_pos == Packet::EntityUpdate::MAX_ENTITIES) {
 338                         pack.WriteEntityCount(entity_pos);
 339                         Send(Packet::EntityUpdate::GetSize(entity_pos));
 340                         pack = Prepare<Packet::EntityUpdate>();
 341                         entity_pos = 0;
 342                 }
 343         }
 344         if (entity_pos > 0) {
 345                 pack.WriteEntityCount(entity_pos);
 346                 Send(Packet::EntityUpdate::GetSize(entity_pos));
 347         }
 348         entity_updates.clear();
 349         entity_updates_skipped = 0;
 350 }
 351
 352 void ClientConnection::CheckPlayerFix() {
 353         // player_update_state's position holds the client's most recent prediction
 354         glm::vec3 diff = player_update_state.Diff(PlayerEntity().GetState());
 355         float dist_squared = dot(diff, diff);
 356
 357         // if client's prediction is off by more than 1cm, send
 358         // our (authoritative) state back so it can fix it
 359         constexpr float fix_thresh = 0.0001f;
 360
 361         if (dist_squared > fix_thresh) {
 362                 auto pack = Prepare<Packet::PlayerCorrection>();
 363                 pack.WritePacketSeq(player_update_pack);
 364                 pack.WritePlayer(PlayerEntity());
 365                 Send();
 366         }
 367 }
 368
 369 namespace {
 370
 371 struct QueueCompare {
 372         explicit QueueCompare(const glm::ivec3 &base)
 373         : base(base) { }
 374         bool operator ()(const glm::ivec3 &left, const glm::ivec3 &right) const noexcept {
 375                 const glm::ivec3 ld(left - base);
 376                 const glm::ivec3 rd(right - base);
 377                 return
 378                         ld.x * ld.x + ld.y * ld.y + ld.z * ld.z <
 379                         rd.x * rd.x + rd.y * rd.y + rd.z * rd.z;
 380         }
 381         const glm::ivec3 &base;
 382 };
 383
 384 }
 385
 386 void ClientConnection::CheckChunkQueue() {
 387         if (PlayerChunks().Base() != old_base) {
 388                 ExactLocation::Coarse begin = PlayerChunks().CoordsBegin();
 389                 ExactLocation::Coarse end = PlayerChunks().CoordsEnd();
 390                 for (ExactLocation::Coarse pos = begin; pos.z < end.z; ++pos.z) {
 391                         for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 392                                 for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 393                                         if (manhattan_radius(pos - old_base) > PlayerChunks().Extent()) {
 394                                                 chunk_queue.push_back(pos);
 395                                         }
 396                                 }
 397                         }
 398                 }
 399                 old_base = PlayerChunks().Base();
 400                 sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 401         }
 402         // if we have packet skip enabled and just pushed an entity
 403         // update, don't also send chunk data
 404         if (NetStat().SuggestedPacketSkip() > 0 && entity_updates_skipped == 0) {
 405                 return;
 406         }
 407         if (transmitter.Transmitting()) {
 408                 transmitter.Transmit();
 409                 return;
 410         }
 411         if (transmitter.Idle()) {
 412                 int count = 0;
 413                 constexpr int max = 64;
 414                 while (count < max && !chunk_queue.empty()) {
 415                         ExactLocation::Coarse pos = chunk_queue.front();
 416                         chunk_queue.pop_front();
 417                         if (PlayerChunks().InRange(pos)) {
 418                                 Chunk *chunk = PlayerChunks().Get(pos);
 419                                 if (chunk) {
 420                                         transmitter.Send(*chunk);
 421                                         return;
 422                                 } else {
 423                                         chunk_queue.push_back(pos);
 424                                 }
 425                                 ++count;
 426                         }
 427                 }
 428         }
 429 }
 430
 431 void ClientConnection::AttachPlayer(Player &player) {
 432         DetachPlayer();
 433         input.reset(new DirectInput(server.GetWorld(), player, server));
 434         PlayerEntity().Ref();
 435
 436         old_base = PlayerChunks().Base();
 437         ExactLocation::Coarse begin = PlayerChunks().CoordsBegin();
 438         ExactLocation::Coarse end = PlayerChunks().CoordsEnd();
 439         for (ExactLocation::Coarse pos = begin; pos.z < end.z; ++pos.z) {
 440                 for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
 441                         for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
 442                                 chunk_queue.push_back(pos);
 443                         }
 444                 }
 445         }
 446         sort(chunk_queue.begin(), chunk_queue.end(), QueueCompare(old_base));
 447         // TODO: should the server do this?
 448         if (HasPlayerModel()) {
 449                 GetPlayerModel().Instantiate(PlayerEntity().GetModel());
 450         }
 451
 452         string msg = "player \"" + player.Name() + "\" joined";
 453         cout << msg << endl;
 454         server.DistributeMessage(0, 0, msg);
 455 }
 456
 457 void ClientConnection::DetachPlayer() {
 458         if (!HasPlayer()) return;
 459         string msg = "player \"" + input->GetPlayer().Name() + "\" left";
 460         cout << msg << endl;
 461         server.DistributeMessage(0, 0, msg);
 462
 463         server.GetWorldSave().Write(input->GetPlayer());
 464         PlayerEntity().Kill();
 465         PlayerEntity().UnRef();
 466         input.reset();
 467         transmitter.Abort();
 468         chunk_queue.clear();
 469         old_actions = 0;
 470 }
 471
 472 void ClientConnection::SetPlayerModel(const Model &m) noexcept {
 473         player_model = &m;
 474         if (HasPlayer()) {
 475                 m.Instantiate(PlayerEntity().GetModel());
 476         }
 477 }
 478
 479 bool ClientConnection::HasPlayerModel() const noexcept {
 480         return player_model;
 481 }
 482
 483 const Model &ClientConnection::GetPlayerModel() const noexcept {
 484         return *player_model;
 485 }
 486
 487 void ClientConnection::OnPacketReceived(uint16_t seq) {
 488         if (transmitter.Waiting()) {
 489                 transmitter.Ack(seq);
 490         }
 491         if (!confirm_wait) return;
 492         for (auto iter = spawns.begin(), end = spawns.end(); iter != end; ++iter) {
 493                 if (seq == iter->spawn_pack) {
 494                         iter->spawn_pack = -1;
 495                         --confirm_wait;
 496                         return;
 497                 }
 498                 if (seq == iter->despawn_pack) {
 499                         spawns.erase(iter);
 500                         --confirm_wait;
 501                         return;
 502                 }
 503         }
 504 }
 505
 506 void ClientConnection::OnPacketLost(uint16_t seq) {
 507         if (transmitter.Waiting()) {
 508                 transmitter.Nack(seq);
 509         }
 510         if (!confirm_wait) return;
 511         for (SpawnStatus &status : spawns) {
 512                 if (seq == status.spawn_pack) {
 513                         status.spawn_pack = -1;
 514                         --confirm_wait;
 515                         SendSpawn(status);
 516                         return;
 517                 }
 518                 if (seq == status.despawn_pack) {
 519                         status.despawn_pack = -1;
 520                         --confirm_wait;
 521                         SendDespawn(status);
 522                         return;
 523                 }
 524         }
 525 }
 526
 527 void ClientConnection::On(const Packet::Login &pack) {
 528         string name;
 529         pack.ReadPlayerName(name);
 530
 531         Player *new_player = server.JoinPlayer(name);
 532
 533         if (new_player) {
 534                 // success!
 535                 AttachPlayer(*new_player);
 536                 cout << "accepted login from player \"" << name << '"' << endl;
 537                 auto response = Prepare<Packet::Join>();
 538                 response.WritePlayer(new_player->GetEntity());
 539                 response.WriteWorldName(server.GetWorld().Name());
 540                 Send();
 541                 // set up update tracking
 542                 player_update_state = new_player->GetEntity().GetState();
 543                 player_update_pack = pack.Seq();
 544                 player_update_timer.Reset();
 545                 player_update_timer.Start();
 546         } else {
 547                 // aw no :(
 548                 cout << "rejected login from player \"" << name << '"' << endl;
 549                 Prepare<Packet::Part>();
 550                 Send();
 551                 conn.Close();
 552         }
 553 }
 554
 555 void ClientConnection::On(const Packet::Part &) {
 556         conn.Close();
 557 }
 558
 559 void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 560         if (!HasPlayer()) return;
 561         int pack_diff = int16_t(pack.Seq()) - int16_t(player_update_pack);
 562         bool overdue = player_update_timer.HitOnce();
 563         player_update_timer.Reset();
 564         if (pack_diff <= 0 && !overdue) {
 565                 // drop old packets if we have a fairly recent state
 566                 return;
 567         }
 568         glm::vec3 movement(0.0f);
 569         uint8_t new_actions;
 570         uint8_t slot;
 571
 572         player_update_pack = pack.Seq();
 573         pack.ReadPredictedState(player_update_state);
 574         pack.ReadMovement(movement);
 575         pack.ReadActions(new_actions);
 576         pack.ReadSlot(slot);
 577
 578         input->SetMovement(movement);
 579         input->TurnHead(player_update_state.pitch - input->GetPitch(), player_update_state.yaw - input->GetYaw());
 580         input->SelectInventory(slot);
 581
 582         if ((new_actions & 0x01) && !(old_actions & 0x01)) {
 583                 input->StartPrimaryAction();
 584         } else if (!(new_actions & 0x01) && (old_actions & 0x01)) {
 585                 input->StopPrimaryAction();
 586         }
 587         if ((new_actions & 0x02) && !(old_actions & 0x02)) {
 588                 input->StartSecondaryAction();
 589         } else if (!(new_actions & 0x02) && (old_actions & 0x02)) {
 590                 input->StopSecondaryAction();
 591         }
 592         if ((new_actions & 0x04) && !(old_actions & 0x04)) {
 593                 input->StartTertiaryAction();
 594         } else if (!(new_actions & 0x04) && (old_actions & 0x04)) {
 595                 input->StopTertiaryAction();
 596         }
 597         old_actions = new_actions;
 598 }
 599
 600 bool ClientConnection::ChunkInRange(const glm::ivec3 &pos) const noexcept {
 601         return HasPlayer() && PlayerChunks().InRange(pos);
 602 }
 603
 604 void ClientConnection::On(const Packet::Message &pack) {
 605         uint8_t type;
 606         uint32_t ref;
 607         string msg;
 608         pack.ReadType(type);
 609         pack.ReadReferral(ref);
 610         pack.ReadMessage(msg);
 611
 612         if (type == 1 && HasPlayer()) {
 613                 server.DispatchMessage(input->GetPlayer(), msg);
 614         }
 615 }
 616
 617
 618 Server::Server(
 619         const Config::Network &conf,
 620         World &world,
 621         const World::Config &wc,
 622         const WorldSave &save)
 623 : serv_sock(nullptr)
 624 , serv_pack{ -1, nullptr, 0 }
 625 , clients()
 626 , world(world)
 627 , spawn_index(world.Chunks().MakeIndex(wc.spawn, 3))
 628 , save(save)
 629 , player_model(nullptr)
 630 , cli(world) {
 631         serv_sock = SDLNet_UDP_Open(conf.port);
 632         if (!serv_sock) {
 633                 throw NetError("SDLNet_UDP_Open");
 634         }
 635
 636         serv_pack.data = new Uint8[sizeof(Packet)];
 637         serv_pack.maxlen = sizeof(Packet);
 638 }
 639
 640 Server::~Server() {
 641         world.Chunks().UnregisterIndex(spawn_index);
 642         delete[] serv_pack.data;
 643         SDLNet_UDP_Close(serv_sock);
 644 }
 645
 646
 647 void Server::Handle() {
 648         int result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 649         while (result > 0) {
 650                 HandlePacket(serv_pack);
 651                 result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 652         }
 653         if (result == -1) {
 654                 // a boo boo happened
 655                 throw NetError("SDLNet_UDP_Recv");
 656         }
 657 }
 658
 659 void Server::HandlePacket(const UDPpacket &udp_pack) {
 660         if (udp_pack.len < int(sizeof(Packet::Header))) {
 661                 // packet too small, drop
 662                 return;
 663         }
 664         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 665         if (pack.header.tag != Packet::TAG) {
 666                 // mistagged packet, drop
 667                 return;
 668         }
 669
 670         ClientConnection &client = GetClient(udp_pack.address);
 671         client.GetConnection().Received(udp_pack);
 672 }
 673
 674 ClientConnection &Server::GetClient(const IPaddress &addr) {
 675         for (ClientConnection &client : clients) {
 676                 if (client.Matches(addr)) {
 677                         return client;
 678                 }
 679         }
 680         clients.emplace_back(*this, addr);
 681         if (HasPlayerModel()) {
 682                 clients.back().SetPlayerModel(GetPlayerModel());
 683         }
 684         return clients.back();
 685 }
 686
 687 void Server::Update(int dt) {
 688         for (list<ClientConnection>::iterator client(clients.begin()), end(clients.end()); client != end;) {
 689                 client->Update(dt);
 690                 if (client->Disconnected()) {
 691                         client = clients.erase(client);
 692                 } else {
 693                         ++client;
 694                 }
 695         }
 696 }
 697
 698 void Server::SetPlayerModel(const Model &m) noexcept {
 699         player_model = &m;
 700         for (ClientConnection &client : clients) {
 701                 client.SetPlayerModel(m);
 702         }
 703 }
 704
 705 bool Server::HasPlayerModel() const noexcept {
 706         return player_model;
 707 }
 708
 709 const Model &Server::GetPlayerModel() const noexcept {
 710         return *player_model;
 711 }
 712
 713 Player *Server::JoinPlayer(const string &name) {
 714         if (spawn_index.MissingChunks() > 0) {
 715                 return nullptr;
 716         }
 717         Player *player = world.AddPlayer(name);
 718         if (!player) {
 719                 return nullptr;
 720         }
 721         if (save.Exists(*player)) {
 722                 save.Read(*player);
 723         } else {
 724                 // TODO: spawn
 725         }
 726         return player;
 727 }
 728
 729 void Server::SetBlock(Chunk &chunk, int index, const Block &block) {
 730         chunk.SetBlock(index, block);
 731         // TODO: batch chunk changes
 732         auto pack = Packet::Make<Packet::BlockUpdate>(GetPacket());
 733         pack.WriteChunkCoords(chunk.Position());
 734         pack.WriteBlockCount(uint32_t(1));
 735         pack.WriteIndex(index, 0);
 736         pack.WriteBlock(chunk.BlockAt(index), 0);
 737         GetPacket().len = sizeof(Packet::Header) + Packet::BlockUpdate::GetSize(1);
 738         for (ClientConnection &client : clients) {
 739                 if (client.ChunkInRange(chunk.Position())) {
 740                         client.Send();
 741                 }
 742         }
 743 }
 744
 745 void Server::DispatchMessage(Player &player, const string &msg) {
 746         if (msg.empty()) {
 747                 return;
 748         }
 749         if (msg[0] == '/' && msg.size() > 1 && msg[1] != '/') {
 750                 cli.Execute(player, msg.substr(1));
 751         } else {
 752                 DistributeMessage(1, player.GetEntity().ID(), msg);
 753         }
 754 }
 755
 756 void Server::DistributeMessage(uint8_t type, uint32_t ref, const string &msg) {
 757         auto pack = Packet::Make<Packet::Message>(serv_pack);
 758         pack.WriteType(type);
 759         pack.WriteReferral(ref);
 760         pack.WriteMessage(msg);
 761         serv_pack.len = sizeof(Packet::Header) + Packet::Message::GetSize(msg);
 762         SendAll();
 763 }
 764
 765 void Server::SendAll() {
 766         for (ClientConnection &client : clients) {
 767                 client.GetConnection().Send(serv_pack, serv_sock);
 768         }
 769 }
 770
 771 }
 772 }