src/net/net.cpp

   1 #include "Client.hpp"
   2 #include "ClientConnection.hpp"
   3 #include "Connection.hpp"
   4 #include "ConnectionHandler.hpp"
   5 #include "io.hpp"
   6 #include "Packet.hpp"
   7 #include "Server.hpp"
   8
   9 #include "../app/init.hpp"
  10 #include "../model/CompositeModel.hpp"
  11 #include "../world/World.hpp"
  12
  13 #include <cstring>
  14 #include <iostream>
  15 #include <glm/gtx/io.hpp>
  16
  17 using namespace std;
  18
  19
  20 namespace blank {
  21
  22 constexpr size_t Packet::Ping::MAX_LEN;
  23 constexpr size_t Packet::Login::MAX_LEN;
  24 constexpr size_t Packet::Join::MAX_LEN;
  25 constexpr size_t Packet::Part::MAX_LEN;
  26 constexpr size_t Packet::PlayerUpdate::MAX_LEN;
  27 constexpr size_t Packet::SpawnEntity::MAX_LEN;
  28 constexpr size_t Packet::DespawnEntity::MAX_LEN;
  29 constexpr size_t Packet::EntityUpdate::MAX_LEN;
  30
  31 namespace {
  32
  33 UDPsocket client_bind(Uint16 port) {
  34         UDPsocket sock = SDLNet_UDP_Open(port);
  35         if (!sock) {
  36                 throw NetError("SDLNet_UDP_Open");
  37         }
  38         return sock;
  39 }
  40
  41 IPaddress client_resolve(const char *host, Uint16 port) {
  42         IPaddress addr;
  43         if (SDLNet_ResolveHost(&addr, host, port) != 0) {
  44                 throw NetError("SDLNet_ResolveHost");
  45         }
  46         return addr;
  47 }
  48
  49 }
  50
  51 Client::Client(const Config &conf)
  52 : conn(client_resolve(conf.host.c_str(), conf.port))
  53 , client_sock(client_bind(0))
  54 , client_pack{ -1, nullptr, 0 } {
  55         client_pack.data = new Uint8[sizeof(Packet)];
  56         client_pack.maxlen = sizeof(Packet);
  57         // establish connection
  58         SendPing();
  59 }
  60
  61 Client::~Client() {
  62         delete[] client_pack.data;
  63         SDLNet_UDP_Close(client_sock);
  64 }
  65
  66
  67 void Client::Handle() {
  68         int result = SDLNet_UDP_Recv(client_sock, &client_pack);
  69         while (result > 0) {
  70                 HandlePacket(client_pack);
  71                 result = SDLNet_UDP_Recv(client_sock, &client_pack);
  72         }
  73         if (result == -1) {
  74                 // a boo boo happened
  75                 throw NetError("SDLNet_UDP_Recv");
  76         }
  77 }
  78
  79 void Client::HandlePacket(const UDPpacket &udp_pack) {
  80         if (!conn.Matches(udp_pack.address)) {
  81                 // packet came from somewhere else, drop
  82                 return;
  83         }
  84         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
  85         if (pack.header.tag != Packet::TAG) {
  86                 // mistagged packet, drop
  87                 return;
  88         }
  89
  90         conn.Received(udp_pack);
  91 }
  92
  93 void Client::Update(int dt) {
  94         conn.Update(dt);
  95         if (conn.ShouldPing()) {
  96                 SendPing();
  97         }
  98 }
  99
 100 uint16_t Client::SendPing() {
 101         return conn.SendPing(client_pack, client_sock);
 102 }
 103
 104 uint16_t Client::SendLogin(const string &name) {
 105         auto pack = Packet::Make<Packet::Login>(client_pack);
 106         pack.WritePlayerName(name);
 107         return conn.Send(client_pack, client_sock);
 108 }
 109
 110 uint16_t Client::SendPlayerUpdate(const Entity &player) {
 111         auto pack = Packet::Make<Packet::PlayerUpdate>(client_pack);
 112         pack.WritePlayer(player);
 113         return conn.Send(client_pack, client_sock);
 114 }
 115
 116 uint16_t Client::SendPart() {
 117         Packet::Make<Packet::Part>(client_pack);
 118         return conn.Send(client_pack, client_sock);
 119 }
 120
 121
 122 ClientConnection::ClientConnection(Server &server, const IPaddress &addr)
 123 : server(server)
 124 , conn(addr)
 125 , player(nullptr)
 126 , spawns()
 127 , confirm_wait(0) {
 128         conn.SetHandler(this);
 129 }
 130
 131 ClientConnection::~ClientConnection() {
 132         DetachPlayer();
 133 }
 134
 135 void ClientConnection::Update(int dt) {
 136         conn.Update(dt);
 137         if (Disconnected()) {
 138                 return;
 139         }
 140         if (HasPlayer()) {
 141                 // sync entities
 142                 auto global_iter = server.GetWorld().Entities().begin();
 143                 auto global_end = server.GetWorld().Entities().end();
 144                 auto local_iter = spawns.begin();
 145                 auto local_end = spawns.end();
 146
 147                 while (global_iter != global_end && local_iter != local_end) {
 148                         if (global_iter->ID() == local_iter->entity->ID()) {
 149                                 // they're the same
 150                                 if (CanDespawn(*global_iter)) {
 151                                         SendDespawn(*local_iter);
 152                                 } else {
 153                                         // update
 154                                         SendUpdate(*local_iter);
 155                                 }
 156                                 ++global_iter;
 157                                 ++local_iter;
 158                         } else if (global_iter->ID() < local_iter->entity->ID()) {
 159                                 // global entity was inserted
 160                                 if (CanSpawn(*global_iter)) {
 161                                         auto spawned = spawns.emplace(local_iter, *global_iter);
 162                                         SendSpawn(*spawned);
 163                                 }
 164                                 ++global_iter;
 165                         } else {
 166                                 // global entity was removed
 167                                 SendDespawn(*local_iter);
 168                                 ++local_iter;
 169                         }
 170                 }
 171
 172                 // leftover spawns
 173                 while (global_iter != global_end) {
 174                         if (CanSpawn(*global_iter)) {
 175                                 spawns.emplace_back(*global_iter);
 176                                 SendSpawn(spawns.back());
 177                         }
 178                         ++global_iter;
 179                 }
 180
 181                 // leftover despawns
 182                 while (local_iter != local_end) {
 183                         SendDespawn(*local_iter);
 184                         ++local_iter;
 185                 }
 186         }
 187         if (conn.ShouldPing()) {
 188                 conn.SendPing(server.GetPacket(), server.GetSocket());
 189         }
 190 }
 191
 192 ClientConnection::SpawnStatus::SpawnStatus(Entity &e)
 193 : entity(&e)
 194 , spawn_pack(-1)
 195 , despawn_pack(-1) {
 196         entity->Ref();
 197 }
 198
 199 ClientConnection::SpawnStatus::~SpawnStatus() {
 200         entity->UnRef();
 201 }
 202
 203 bool ClientConnection::CanSpawn(const Entity &e) const noexcept {
 204         return
 205                 &e != player &&
 206                 !e.Dead() &&
 207                 manhattan_radius(e.ChunkCoords() - Player().ChunkCoords()) < 7;
 208 }
 209
 210 bool ClientConnection::CanDespawn(const Entity &e) const noexcept {
 211         return
 212                 e.Dead() ||
 213                 manhattan_radius(e.ChunkCoords() - Player().ChunkCoords()) > 7;
 214 }
 215
 216 void ClientConnection::SendSpawn(SpawnStatus &status) {
 217         // don't double spawn
 218         if (status.spawn_pack != -1) return;
 219
 220         auto pack = Packet::Make<Packet::SpawnEntity>(server.GetPacket());
 221         pack.WriteEntity(*status.entity);
 222         status.spawn_pack = conn.Send(server.GetPacket(), server.GetSocket());
 223         ++confirm_wait;
 224 }
 225
 226 void ClientConnection::SendDespawn(SpawnStatus &status) {
 227         // don't double despawn
 228         if (status.despawn_pack != -1) return;
 229
 230         auto pack = Packet::Make<Packet::DespawnEntity>(server.GetPacket());
 231         pack.WriteEntityID(status.entity->ID());
 232         status.despawn_pack = conn.Send(server.GetPacket(), server.GetSocket());
 233         ++confirm_wait;
 234 }
 235
 236 void ClientConnection::SendUpdate(SpawnStatus &status) {
 237         // don't send updates while spawn not ack'd or despawn sent
 238         if (status.spawn_pack != -1 || status.despawn_pack != -1) return;
 239
 240         // TODO: pack entity updates
 241         auto pack = Packet::Make<Packet::EntityUpdate>(server.GetPacket());
 242         pack.WriteEntityCount(1);
 243         pack.WriteEntity(*status.entity, 0);
 244         server.GetPacket().len = Packet::EntityUpdate::GetSize(1);
 245         conn.Send(server.GetPacket(), server.GetSocket());
 246 }
 247
 248 void ClientConnection::AttachPlayer(Entity &new_player) {
 249         DetachPlayer();
 250         player = &new_player;
 251         player->Ref();
 252         cout << "player \"" << player->Name() << "\" joined" << endl;
 253 }
 254
 255 void ClientConnection::DetachPlayer() {
 256         if (!player) return;
 257         player->Kill();
 258         player->UnRef();
 259         cout << "player \"" << player->Name() << "\" left" << endl;
 260         player = nullptr;
 261 }
 262
 263 void ClientConnection::OnPacketReceived(uint16_t seq) {
 264         if (!confirm_wait) return;
 265         for (auto iter = spawns.begin(), end = spawns.end(); iter != end; ++iter) {
 266                 if (seq == iter->spawn_pack) {
 267                         iter->spawn_pack = -1;
 268                         --confirm_wait;
 269                         return;
 270                 }
 271                 if (seq == iter->despawn_pack) {
 272                         spawns.erase(iter);
 273                         --confirm_wait;
 274                         return;
 275                 }
 276         }
 277 }
 278
 279 void ClientConnection::OnPacketLost(uint16_t seq) {
 280         if (!confirm_wait) return;
 281         for (SpawnStatus &status : spawns) {
 282                 if (seq == status.spawn_pack) {
 283                         status.spawn_pack = -1;
 284                         --confirm_wait;
 285                         SendSpawn(status);
 286                         return;
 287                 }
 288                 if (seq == status.despawn_pack) {
 289                         status.despawn_pack = -1;
 290                         --confirm_wait;
 291                         SendDespawn(status);
 292                         return;
 293                 }
 294         }
 295 }
 296
 297 void ClientConnection::On(const Packet::Login &pack) {
 298         string name;
 299         pack.ReadPlayerName(name);
 300
 301         Entity *new_player = server.GetWorld().AddPlayer(name).entity;
 302
 303         if (new_player) {
 304                 // success!
 305                 AttachPlayer(*new_player);
 306                 cout << "accepted login from player \"" << name << '"' << endl;
 307                 auto response = Packet::Make<Packet::Join>(server.GetPacket());
 308                 response.WritePlayer(*new_player);
 309                 response.WriteWorldName(server.GetWorld().Name());
 310                 conn.Send(server.GetPacket(), server.GetSocket());
 311         } else {
 312                 // aw no :(
 313                 cout << "rejected login from player \"" << name << '"' << endl;
 314                 Packet::Make<Packet::Part>(server.GetPacket());
 315                 conn.Send(server.GetPacket(), server.GetSocket());
 316                 conn.Close();
 317         }
 318 }
 319
 320 void ClientConnection::On(const Packet::Part &) {
 321         conn.Close();
 322 }
 323
 324 void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 325         if (!HasPlayer()) return;
 326         pack.ReadPlayer(Player());
 327 }
 328
 329
 330 Connection::Connection(const IPaddress &addr)
 331 : handler(nullptr)
 332 , addr(addr)
 333 , send_timer(500)
 334 , recv_timer(10000)
 335 , ctrl_out{ 0, 0xFFFF, 0xFFFFFFFF }
 336 , ctrl_in{ 0, 0xFFFF, 0xFFFFFFFF }
 337 , closed(false) {
 338         send_timer.Start();
 339         recv_timer.Start();
 340 }
 341
 342 bool Connection::Matches(const IPaddress &remote) const noexcept {
 343         return memcmp(&addr, &remote, sizeof(IPaddress)) == 0;
 344 }
 345
 346 void Connection::FlagSend() noexcept {
 347         send_timer.Reset();
 348 }
 349
 350 void Connection::FlagRecv() noexcept {
 351         recv_timer.Reset();
 352 }
 353
 354 bool Connection::ShouldPing() const noexcept {
 355         return !closed && send_timer.HitOnce();
 356 }
 357
 358 bool Connection::TimedOut() const noexcept {
 359         return recv_timer.HitOnce();
 360 }
 361
 362 void Connection::Update(int dt) {
 363         send_timer.Update(dt);
 364         recv_timer.Update(dt);
 365         if (TimedOut()) {
 366                 Close();
 367                 if (HasHandler()) {
 368                         Handler().OnTimeout();
 369                 }
 370         }
 371 }
 372
 373
 374 uint16_t Connection::Send(UDPpacket &udp_pack, UDPsocket sock) {
 375         Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
 376         pack.header.ctrl = ctrl_out;
 377         uint16_t seq = ctrl_out.seq++;
 378
 379         udp_pack.address = addr;
 380         if (SDLNet_UDP_Send(sock, -1, &udp_pack) == 0) {
 381                 throw NetError("SDLNet_UDP_Send");
 382         }
 383
 384         FlagSend();
 385         return seq;
 386 }
 387
 388 void Connection::Received(const UDPpacket &udp_pack) {
 389         Packet &pack = *reinterpret_cast<Packet *>(udp_pack.data);
 390
 391         // ack to the remote
 392         int16_t diff = int16_t(pack.header.ctrl.seq) - int16_t(ctrl_out.ack);
 393         if (diff > 0) {
 394                 if (diff >= 32) {
 395                         ctrl_out.hist = 0;
 396                 } else {
 397                         ctrl_out.hist <<= diff;
 398                         ctrl_out.hist |= 1 << (diff - 1);
 399                 }
 400         } else if (diff < 0 && diff >= -32) {
 401                 ctrl_out.hist |= 1 << (-diff - 1);
 402         }
 403         ctrl_out.ack = pack.header.ctrl.seq;
 404         FlagRecv();
 405
 406         if (!HasHandler()) {
 407                 return;
 408         }
 409
 410         Packet::TControl ctrl_new = pack.header.ctrl;
 411         Handler().Handle(udp_pack);
 412
 413         if (diff > 0) {
 414                 // if the packet holds more recent information
 415                 // check if remote failed to ack one of our packets
 416                 diff = int16_t(ctrl_new.ack) - int16_t(ctrl_in.ack);
 417                 // should always be true, but you never know…
 418                 if (diff > 0) {
 419                         for (int i = 0; i < diff; ++i) {
 420                                 if (i > 32 || (i < 32 && (ctrl_in.hist & (1 << (31 - i))) == 0)) {
 421                                         Handler().OnPacketLost(ctrl_in.ack - 32 + i);
 422                                 }
 423                         }
 424                 }
 425                 // check for newly ack'd packets
 426                 for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); ++s) {
 427                         if (ctrl_new.Acks(s) && !ctrl_in.Acks(s)) {
 428                                 Handler().OnPacketReceived(s);
 429                         }
 430                 }
 431                 ctrl_in = ctrl_new;
 432         }
 433 }
 434
 435 bool Packet::TControl::Acks(uint16_t s) const noexcept {
 436         int16_t diff = int16_t(ack) - int16_t(s);
 437         if (diff == 0) return true;
 438         if (diff < 0 || diff > 32) return false;
 439         return (hist & (1 << (diff - 1))) != 0;
 440 }
 441
 442 uint16_t Connection::SendPing(UDPpacket &udp_pack, UDPsocket sock) {
 443         Packet::Make<Packet::Ping>(udp_pack);
 444         return Send(udp_pack, sock);
 445 }
 446
 447
 448 ostream &operator <<(ostream &out, const IPaddress &addr) {
 449         const unsigned char *host = reinterpret_cast<const unsigned char *>(&addr.host);
 450         out << int(host[0])
 451                 << '.' << int(host[1])
 452                 << '.' << int(host[2])
 453                 << '.' << int(host[3]);
 454         if (addr.port) {
 455                 out << ':' << SDLNet_Read16(&addr.port);
 456         }
 457         return out;
 458 }
 459
 460
 461 const char *Packet::Type2String(uint8_t t) noexcept {
 462         switch (t) {
 463                 case Ping::TYPE:
 464                         return "Ping";
 465                 case Login::TYPE:
 466                         return "Login";
 467                 case Join::TYPE:
 468                         return "Join";
 469                 case Part::TYPE:
 470                         return "Part";
 471                 case PlayerUpdate::TYPE:
 472                         return "PlayerUpdate";
 473                 case SpawnEntity::TYPE:
 474                         return "SpawnEntity";
 475                 case DespawnEntity::TYPE:
 476                         return "DespawnEntity";
 477                 case EntityUpdate::TYPE:
 478                         return "EntityUpdate";
 479                 default:
 480                         return "Unknown";
 481         }
 482 }
 483
 484 template<class T>
 485 void Packet::Payload::Write(const T &src, size_t off) noexcept {
 486         if ((length - off) < sizeof(T)) {
 487                 // dismiss out of bounds write
 488                 return;
 489         }
 490         *reinterpret_cast<T *>(&data[off]) = src;
 491 }
 492
 493 template<class T>
 494 void Packet::Payload::Read(T &dst, size_t off) const noexcept {
 495         if ((length - off) < sizeof(T)) {
 496                 // dismiss out of bounds read
 497                 return;
 498         }
 499         dst = *reinterpret_cast<T *>(&data[off]);
 500 }
 501
 502 void Packet::Payload::WriteString(const string &src, size_t off, size_t maxlen) noexcept {
 503         uint8_t *dst = &data[off];
 504         size_t len = min(maxlen, length - off);
 505         if (src.size() < len) {
 506                 memset(dst, '\0', len);
 507                 memcpy(dst, src.c_str(), src.size());
 508         } else {
 509                 memcpy(dst, src.c_str(), len);
 510         }
 511 }
 512
 513 void Packet::Payload::ReadString(string &dst, size_t off, size_t maxlen) const noexcept {
 514         size_t len = min(maxlen, length - off);
 515         dst.clear();
 516         dst.reserve(len);
 517         for (size_t i = 0; i < len && data[off + i] != '\0'; ++i) {
 518                 dst.push_back(data[off + i]);
 519         }
 520 }
 521
 522
 523 void Packet::Login::WritePlayerName(const string &name) noexcept {
 524         WriteString(name, 0, 32);
 525 }
 526
 527 void Packet::Login::ReadPlayerName(string &name) const noexcept {
 528         ReadString(name, 0, 32);
 529 }
 530
 531 void Packet::Join::WritePlayer(const Entity &player) noexcept {
 532         Write(player.ID(), 0);
 533         Write(player.ChunkCoords(), 4);
 534         Write(player.Position(), 16);
 535         Write(player.Velocity(), 28);
 536         Write(player.Orientation(), 40);
 537         Write(player.AngularVelocity(), 56);
 538 }
 539
 540 void Packet::Join::ReadPlayerID(uint32_t &id) const noexcept {
 541         Read(id, 0);
 542 }
 543
 544 void Packet::Join::ReadPlayer(Entity &player) const noexcept {
 545         glm::ivec3 chunk_coords(0);
 546         glm::vec3 pos;
 547         glm::vec3 vel;
 548         glm::quat rot;
 549         glm::vec3 ang;
 550
 551         Read(chunk_coords, 4);
 552         Read(pos, 16);
 553         Read(vel, 28);
 554         Read(rot, 40);
 555         Read(ang, 56);
 556
 557         player.Position(chunk_coords, pos);
 558         player.Velocity(vel);
 559         player.Orientation(rot);
 560         player.AngularVelocity(ang);
 561 }
 562
 563 void Packet::Join::WriteWorldName(const string &name) noexcept {
 564         WriteString(name, 68, 32);
 565 }
 566
 567 void Packet::Join::ReadWorldName(string &name) const noexcept {
 568         ReadString(name, 68, 32);
 569 }
 570
 571 void Packet::PlayerUpdate::WritePlayer(const Entity &player) noexcept {
 572         Write(player.ChunkCoords(), 0);
 573         Write(player.Position(), 12);
 574         Write(player.Velocity(), 24);
 575         Write(player.Orientation(), 36);
 576         Write(player.AngularVelocity(), 52);
 577 }
 578
 579 void Packet::PlayerUpdate::ReadPlayer(Entity &player) const noexcept {
 580         glm::ivec3 chunk_coords(0);
 581         glm::vec3 pos;
 582         glm::vec3 vel;
 583         glm::quat rot;
 584         glm::vec3 ang;
 585
 586         Read(chunk_coords, 0);
 587         Read(pos, 12);
 588         Read(vel, 24);
 589         Read(rot, 36);
 590         Read(ang, 52);
 591
 592         player.Position(chunk_coords, pos);
 593         player.Velocity(vel);
 594         player.Orientation(rot);
 595         player.AngularVelocity(ang);
 596 }
 597
 598 void Packet::SpawnEntity::WriteEntity(const Entity &e) noexcept {
 599         Write(e.ID(), 0);
 600         if (e.GetModel()) {
 601                 Write(e.GetModel().GetModel().ID(), 4);
 602         } else {
 603                 Write(uint32_t(0), 4);
 604         }
 605         Write(e.ChunkCoords(), 8);
 606         Write(e.Position(), 20);
 607         Write(e.Velocity(), 32);
 608         Write(e.Orientation(), 44);
 609         Write(e.AngularVelocity(), 60);
 610         Write(e.Bounds(), 72);
 611         uint32_t flags = 0;
 612         if (e.WorldCollidable()) {
 613                 flags |= 1;
 614         }
 615         Write(flags, 96);
 616         WriteString(e.Name(), 100, 32);
 617 }
 618
 619 void Packet::SpawnEntity::ReadEntityID(uint32_t &id) const noexcept {
 620         Read(id, 0);
 621 }
 622
 623 void Packet::SpawnEntity::ReadSkeletonID(uint32_t &id) const noexcept {
 624         Read(id, 4);
 625 }
 626
 627 void Packet::SpawnEntity::ReadEntity(Entity &e) const noexcept {
 628         glm::ivec3 chunk_coords(0);
 629         glm::vec3 pos;
 630         glm::vec3 vel;
 631         glm::quat rot;
 632         glm::vec3 ang;
 633         AABB bounds;
 634         uint32_t flags = 0;
 635         string name;
 636
 637         Read(chunk_coords, 8);
 638         Read(pos, 20);
 639         Read(vel, 32);
 640         Read(rot, 44);
 641         Read(ang, 60);
 642         Read(bounds, 72);
 643         Read(flags, 96);
 644         ReadString(name, 100, 32);
 645
 646         e.Position(chunk_coords, pos);
 647         e.Velocity(vel);
 648         e.Orientation(rot);
 649         e.AngularVelocity(ang);
 650         e.Bounds(bounds);
 651         e.WorldCollidable(flags & 1);
 652         e.Name(name);
 653 }
 654
 655 void Packet::DespawnEntity::WriteEntityID(uint32_t id) noexcept {
 656         Write(id, 0);
 657 }
 658
 659 void Packet::DespawnEntity::ReadEntityID(uint32_t &id) const noexcept {
 660         Read(id, 0);
 661 }
 662
 663 void Packet::EntityUpdate::WriteEntityCount(uint32_t count) noexcept {
 664         Write(count, 0);
 665 }
 666
 667 void Packet::EntityUpdate::ReadEntityCount(uint32_t &count) const noexcept {
 668         Read(count, 0);
 669 }
 670
 671 void Packet::EntityUpdate::WriteEntity(const Entity &entity, uint32_t num) noexcept {
 672         uint32_t off = 4 + (num * 64);
 673
 674         Write(entity.ID(), off);
 675         Write(entity.ChunkCoords(), off + 4);
 676         Write(entity.Position(), off + 16);
 677         Write(entity.Velocity(), off + 28);
 678         Write(entity.Orientation(), off + 40);
 679         Write(entity.AngularVelocity(), off + 56);
 680 }
 681
 682 void Packet::EntityUpdate::ReadEntityID(uint32_t &id, uint32_t num) const noexcept {
 683         Read(id, 4 + (num * 64));
 684 }
 685
 686 void Packet::EntityUpdate::ReadEntity(Entity &entity, uint32_t num) const noexcept {
 687         uint32_t off = 4 + (num * 64);
 688
 689         glm::ivec3 chunk_coords(0);
 690         glm::vec3 pos;
 691         glm::vec3 vel;
 692         glm::quat rot;
 693         glm::vec3 ang;
 694
 695         Read(chunk_coords, off + 4);
 696         Read(pos, off + 16);
 697         Read(vel, off + 28);
 698         Read(rot, off + 40);
 699         Read(ang, off + 56);
 700
 701         entity.Position(chunk_coords, pos);
 702         entity.Velocity(vel);
 703         entity.Orientation(rot);
 704         entity.AngularVelocity(ang);
 705 }
 706
 707
 708 void ConnectionHandler::Handle(const UDPpacket &udp_pack) {
 709         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 710         switch (pack.Type()) {
 711                 case Packet::Ping::TYPE:
 712                         On(Packet::As<Packet::Ping>(udp_pack));
 713                         break;
 714                 case Packet::Login::TYPE:
 715                         On(Packet::As<Packet::Login>(udp_pack));
 716                         break;
 717                 case Packet::Join::TYPE:
 718                         On(Packet::As<Packet::Join>(udp_pack));
 719                         break;
 720                 case Packet::Part::TYPE:
 721                         On(Packet::As<Packet::Part>(udp_pack));
 722                         break;
 723                 case Packet::PlayerUpdate::TYPE:
 724                         On(Packet::As<Packet::PlayerUpdate>(udp_pack));
 725                         break;
 726                 case Packet::SpawnEntity::TYPE:
 727                         On(Packet::As<Packet::SpawnEntity>(udp_pack));
 728                         break;
 729                 case Packet::DespawnEntity::TYPE:
 730                         On(Packet::As<Packet::DespawnEntity>(udp_pack));
 731                         break;
 732                 case Packet::EntityUpdate::TYPE:
 733                         On(Packet::As<Packet::EntityUpdate>(udp_pack));
 734                         break;
 735                 default:
 736                         // drop unknown or unhandled packets
 737                         break;
 738         }
 739 }
 740
 741
 742 Server::Server(const Config &conf, World &world)
 743 : serv_sock(nullptr)
 744 , serv_pack{ -1, nullptr, 0 }
 745 , clients()
 746 , world(world) {
 747         serv_sock = SDLNet_UDP_Open(conf.port);
 748         if (!serv_sock) {
 749                 throw NetError("SDLNet_UDP_Open");
 750         }
 751
 752         serv_pack.data = new Uint8[sizeof(Packet)];
 753         serv_pack.maxlen = sizeof(Packet);
 754 }
 755
 756 Server::~Server() {
 757         delete[] serv_pack.data;
 758         SDLNet_UDP_Close(serv_sock);
 759 }
 760
 761
 762 void Server::Handle() {
 763         int result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 764         while (result > 0) {
 765                 HandlePacket(serv_pack);
 766                 result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
 767         }
 768         if (result == -1) {
 769                 // a boo boo happened
 770                 throw NetError("SDLNet_UDP_Recv");
 771         }
 772 }
 773
 774 void Server::HandlePacket(const UDPpacket &udp_pack) {
 775         if (udp_pack.len < int(sizeof(Packet::Header))) {
 776                 // packet too small, drop
 777                 return;
 778         }
 779         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 780         if (pack.header.tag != Packet::TAG) {
 781                 // mistagged packet, drop
 782                 return;
 783         }
 784
 785         ClientConnection &client = GetClient(udp_pack.address);
 786         client.GetConnection().Received(udp_pack);
 787 }
 788
 789 ClientConnection &Server::GetClient(const IPaddress &addr) {
 790         for (ClientConnection &client : clients) {
 791                 if (client.Matches(addr)) {
 792                         return client;
 793                 }
 794         }
 795         clients.emplace_back(*this, addr);
 796         return clients.back();
 797 }
 798
 799 void Server::Update(int dt) {
 800         for (list<ClientConnection>::iterator client(clients.begin()), end(clients.end()); client != end;) {
 801                 client->Update(dt);
 802                 if (client->Disconnected()) {
 803                         client = clients.erase(client);
 804                 } else {
 805                         ++client;
 806                 }
 807         }
 808 }
 809
 810 }