src/client/net.cpp

   1 #include "ChunkReceiver.hpp"
   2 #include "ChunkTransmission.hpp"
   3 #include "Client.hpp"
   4 #include "NetworkedInput.hpp"
   5
   6 #include "../app/init.hpp"
   7 #include "../io/WorldSave.hpp"
   8 #include "../net/Packet.hpp"
   9 #include "../world/Chunk.hpp"
  10 #include "../world/ChunkStore.hpp"
  11 #include "../world/Player.hpp"
  12 #include "../world/World.hpp"
  13
  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 client {
  23
  24
  25 ChunkReceiver::ChunkReceiver(ChunkStore &store, const WorldSave &save)
  26 : store(store)
  27 , save(save)
  28 , transmissions()
  29 , timer(5000) {
  30         timer.Start();
  31 }
  32
  33 ChunkReceiver::~ChunkReceiver() {
  34
  35 }
  36
  37 void ChunkReceiver::Update(int dt) {
  38         timer.Update(dt);
  39         for (ChunkTransmission &trans : transmissions) {
  40                 if (trans.active && (timer.Elapsed() - trans.last_update) > timer.Interval()) {
  41                         cout << "timeout for transmission of chunk " << trans.coords << endl;
  42                         trans.Clear();
  43                 }
  44         }
  45         if (transmissions.size() > 3) {
  46                 for (auto iter = transmissions.begin(), end = transmissions.end(); iter != end; ++iter) {
  47                         if (!iter->active) {
  48                                 transmissions.erase(iter);
  49                                 break;
  50                         }
  51                 }
  52         }
  53         LoadN(10);
  54         StoreN(10);
  55 }
  56
  57 int ChunkReceiver::ToLoad() const noexcept {
  58         return store.EstimateMissing();
  59 }
  60
  61 void ChunkReceiver::LoadOne() {
  62         if (!store.HasMissing()) return;
  63
  64         Chunk::Pos pos = store.NextMissing();
  65         Chunk *chunk = store.Allocate(pos);
  66         if (!chunk) {
  67                 // chunk store corrupted?
  68                 return;
  69         }
  70
  71         if (save.Exists(pos)) {
  72                 save.Read(*chunk);
  73         }
  74 }
  75
  76 void ChunkReceiver::LoadN(size_t n) {
  77         size_t end = min(n, size_t(ToLoad()));
  78         for (size_t i = 0; i < end && store.HasMissing(); ++i) {
  79                 LoadOne();
  80         }
  81 }
  82
  83 void ChunkReceiver::StoreN(size_t n) {
  84         size_t saved = 0;
  85         for (Chunk &chunk : store) {
  86                 if (chunk.ShouldUpdateSave()) {
  87                         save.Write(chunk);
  88                         ++saved;
  89                         if (saved >= n) {
  90                                 break;
  91                         }
  92                 }
  93         }
  94 }
  95
  96
  97 void ChunkReceiver::Handle(const Packet::ChunkBegin &pack) {
  98         uint32_t id;
  99         pack.ReadTransmissionId(id);
 100         ChunkTransmission &trans = GetTransmission(id);
 101         pack.ReadFlags(trans.flags);
 102         pack.ReadChunkCoords(trans.coords);
 103         pack.ReadDataSize(trans.data_size);
 104         trans.last_update = timer.Elapsed();
 105         trans.header_received = true;
 106         Commit(trans);
 107 }
 108
 109 void ChunkReceiver::Handle(const Packet::ChunkData &pack) {
 110         uint32_t id, pos, size;
 111         pack.ReadTransmissionId(id);
 112         pack.ReadDataOffset(pos);
 113         if (pos >= sizeof(ChunkTransmission::buffer)) {
 114                 cout << "received chunk data offset outside of buffer size" << endl;
 115                 return;
 116         }
 117         pack.ReadDataSize(size);
 118         ChunkTransmission &trans = GetTransmission(id);
 119         size_t len = min(size_t(size), sizeof(ChunkTransmission::buffer) - pos);
 120         pack.ReadData(&trans.buffer[pos], len);
 121         // TODO: this method breaks when a packet arrives twice
 122         trans.data_received += len;
 123         trans.last_update = timer.Elapsed();
 124         Commit(trans);
 125 }
 126
 127 ChunkTransmission &ChunkReceiver::GetTransmission(uint32_t id) {
 128         // search for ongoing
 129         for (ChunkTransmission &trans : transmissions) {
 130                 if (trans.active && trans.id == id) {
 131                         return trans;
 132                 }
 133         }
 134         // search for unused
 135         for (ChunkTransmission &trans : transmissions) {
 136                 if (!trans.active) {
 137                         trans.active = true;
 138                         trans.id = id;
 139                         return trans;
 140                 }
 141         }
 142         // allocate new
 143         transmissions.emplace_back();
 144         transmissions.back().active = true;
 145         transmissions.back().id = id;
 146         return transmissions.back();
 147 }
 148
 149 void ChunkReceiver::Commit(ChunkTransmission &trans) {
 150         if (!trans.Complete()) return;
 151
 152         Chunk *chunk = store.Allocate(trans.coords);
 153         if (!chunk) {
 154                 // chunk no longer of interes, just drop the data
 155                 // it should probably be cached to disk, but not now :P
 156                 trans.Clear();
 157                 return;
 158         }
 159
 160         const Byte *src = &trans.buffer[0];
 161         uLong src_len = min(size_t(trans.data_size), sizeof(ChunkTransmission::buffer));
 162         Byte *dst = reinterpret_cast<Byte *>(chunk->BlockData());
 163         uLong dst_len = Chunk::BlockSize();
 164
 165         if (trans.Compressed()) {
 166                 if (uncompress(dst, &dst_len, src, src_len) != Z_OK) {
 167                         // omg, now what?
 168                         cout << "got corruped chunk data for " << trans.coords << endl;
 169                 }
 170         } else {
 171                 memcpy(dst, src, min(src_len, dst_len));
 172         }
 173         chunk->Invalidate();
 174         trans.Clear();
 175 }
 176
 177 ChunkTransmission::ChunkTransmission()
 178 : id(0)
 179 , flags(0)
 180 , coords()
 181 , data_size(0)
 182 , data_received(0)
 183 , last_update(0)
 184 , header_received(false)
 185 , active(false)
 186 , buffer() {
 187
 188 }
 189
 190 void ChunkTransmission::Clear() noexcept {
 191         data_size = 0;
 192         data_received = 0;
 193         last_update = 0;
 194         header_received = false;
 195         active = false;
 196 }
 197
 198 bool ChunkTransmission::Complete() const noexcept {
 199         return header_received && data_received == data_size;
 200 }
 201
 202 bool ChunkTransmission::Compressed() const noexcept {
 203         return flags & 1;
 204 }
 205
 206
 207 namespace {
 208
 209 UDPsocket client_bind(Uint16 port) {
 210         UDPsocket sock = SDLNet_UDP_Open(port);
 211         if (!sock) {
 212                 throw NetError("SDLNet_UDP_Open");
 213         }
 214         return sock;
 215 }
 216
 217 IPaddress client_resolve(const char *host, Uint16 port) {
 218         IPaddress addr;
 219         if (SDLNet_ResolveHost(&addr, host, port) != 0) {
 220                 throw NetError("SDLNet_ResolveHost");
 221         }
 222         return addr;
 223 }
 224
 225 }
 226
 227 Client::Client(const Config::Network &conf)
 228 : conn(client_resolve(conf.host.c_str(), conf.port))
 229 , client_sock(client_bind(0))
 230 , client_pack{ -1, nullptr, 0 } {
 231         client_pack.data = new Uint8[sizeof(Packet)];
 232         client_pack.maxlen = sizeof(Packet);
 233         // establish connection
 234         SendPing();
 235 }
 236
 237 Client::~Client() {
 238         delete[] client_pack.data;
 239         SDLNet_UDP_Close(client_sock);
 240 }
 241
 242
 243 void Client::Handle() {
 244         int result = SDLNet_UDP_Recv(client_sock, &client_pack);
 245         while (result > 0) {
 246                 HandlePacket(client_pack);
 247                 result = SDLNet_UDP_Recv(client_sock, &client_pack);
 248         }
 249         if (result == -1) {
 250                 // a boo boo happened
 251                 throw NetError("SDLNet_UDP_Recv");
 252         }
 253 }
 254
 255 void Client::HandlePacket(const UDPpacket &udp_pack) {
 256         if (!conn.Matches(udp_pack.address)) {
 257                 // packet came from somewhere else, drop
 258                 return;
 259         }
 260         const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
 261         if (pack.header.tag != Packet::TAG) {
 262                 // mistagged packet, drop
 263                 return;
 264         }
 265
 266         conn.Received(udp_pack);
 267 }
 268
 269 void Client::Update(int dt) {
 270         conn.Update(dt);
 271         if (conn.ShouldPing()) {
 272                 SendPing();
 273         }
 274 }
 275
 276 uint16_t Client::SendPing() {
 277         return conn.SendPing(client_pack, client_sock);
 278 }
 279
 280 uint16_t Client::SendLogin(const string &name) {
 281         auto pack = Packet::Make<Packet::Login>(client_pack);
 282         pack.WritePlayerName(name);
 283         return conn.Send(client_pack, client_sock);
 284 }
 285
 286 uint16_t Client::SendPlayerUpdate(
 287         const EntityState &prediction,
 288         const glm::vec3 &movement,
 289         float pitch,
 290         float yaw,
 291         uint8_t actions,
 292         uint8_t slot
 293 ) {
 294         auto pack = Packet::Make<Packet::PlayerUpdate>(client_pack);
 295         pack.WritePredictedState(prediction);
 296         pack.WriteMovement(movement);
 297         pack.WritePitch(pitch);
 298         pack.WriteYaw(yaw);
 299         pack.WriteActions(actions);
 300         pack.WriteSlot(slot);
 301         return conn.Send(client_pack, client_sock);
 302 }
 303
 304 uint16_t Client::SendPart() {
 305         Packet::Make<Packet::Part>(client_pack);
 306         return conn.Send(client_pack, client_sock);
 307 }
 308
 309
 310 NetworkedInput::NetworkedInput(World &world, Player &player, Client &client)
 311 : PlayerController(world, player)
 312 , client(client)
 313 , player_hist()
 314 , actions(0) {
 315
 316 }
 317
 318 void NetworkedInput::Update(int dt) {
 319         Invalidate();
 320         UpdatePlayer();
 321 }
 322
 323 void NetworkedInput::PushPlayerUpdate(int dt) {
 324         const EntityState &state = GetPlayer().GetEntity().GetState();
 325
 326         uint16_t packet = client.SendPlayerUpdate(
 327                 state,
 328                 GetMovement(),
 329                 GetPitch(),
 330                 GetYaw(),
 331                 actions,
 332                 InventorySlot()
 333         );
 334         if (player_hist.size() < 16) {
 335                 player_hist.emplace_back(state, GetPlayer().GetEntity().TargetVelocity(), dt * 0.001f, packet);
 336         } else {
 337                 auto entry = player_hist.begin();
 338                 entry->state = state;
 339                 entry->tgt_vel = GetPlayer().GetEntity().TargetVelocity();
 340                 entry->delta_t = dt * 0.001f;
 341                 entry->packet = packet;
 342                 player_hist.splice(player_hist.end(), player_hist, entry);
 343         }
 344 }
 345
 346 void NetworkedInput::MergePlayerCorrection(uint16_t seq, const EntityState &corrected_state) {
 347         if (player_hist.empty()) return;
 348
 349         auto entry = player_hist.begin();
 350         auto end = player_hist.end();
 351
 352         // we may have received an older packet
 353         int pack_diff = int16_t(seq) - int16_t(entry->packet);
 354         if (pack_diff < 0) {
 355                 // indeed we have, just ignore it
 356                 return;
 357         }
 358
 359         // drop anything older than the fix
 360         while (entry != end) {
 361                 pack_diff = int16_t(seq) - int16_t(entry->packet);
 362                 if (pack_diff > 0) {
 363                         entry = player_hist.erase(entry);
 364                 } else {
 365                         break;
 366                 }
 367         }
 368
 369         EntityState &player_state = GetPlayer().GetEntity().GetState();
 370         Entity replay(GetPlayer().GetEntity());
 371         replay.SetState(corrected_state);
 372
 373         if (entry != end) {
 374                 entry->state.chunk_pos = replay.GetState().chunk_pos;
 375                 entry->state.block_pos = replay.GetState().block_pos;
 376                 ++entry;
 377         }
 378
 379         vector<WorldCollision> col;
 380         while (entry != end) {
 381                 replay.Velocity(entry->state.velocity);
 382                 replay.TargetVelocity(entry->tgt_vel);
 383                 GetWorld().Update(replay, entry->delta_t);
 384                 entry->state.chunk_pos = replay.GetState().chunk_pos;
 385                 entry->state.block_pos = replay.GetState().block_pos;
 386                 ++entry;
 387         }
 388
 389         glm::vec3 displacement(replay.GetState().Diff(player_state));
 390         const float disp_squared = dot(displacement, displacement);
 391
 392         if (disp_squared < 16.0f * numeric_limits<float>::epsilon()) {
 393                 return;
 394         }
 395
 396         // if offset > 10cm, warp the player
 397         // otherwise, move at most 1cm per frame towards
 398         // the fixed position (160ms, so shouldn't be too noticeable)
 399         constexpr float warp_thresh = 0.01f; // (1/10)^2
 400         constexpr float max_disp = 0.0001f; // (1/100)^2
 401
 402         if (disp_squared > warp_thresh) {
 403                 player_state.chunk_pos = replay.GetState().chunk_pos;
 404                 player_state.block_pos = replay.GetState().block_pos;
 405         } else if (disp_squared < max_disp) {
 406                 player_state.block_pos += displacement;
 407         } else {
 408                 displacement *= 0.01f / sqrt(disp_squared);
 409                 player_state.block_pos += displacement;
 410         }
 411 }
 412
 413 void NetworkedInput::StartPrimaryAction() {
 414         actions |= 0x01;
 415 }
 416
 417 void NetworkedInput::StopPrimaryAction() {
 418         actions &= ~0x01;
 419 }
 420
 421 void NetworkedInput::StartSecondaryAction() {
 422         actions |= 0x02;
 423 }
 424
 425 void NetworkedInput::StopSecondaryAction() {
 426         actions &= ~0x02;
 427 }
 428
 429 void NetworkedInput::StartTertiaryAction() {
 430         actions |= 0x04;
 431 }
 432
 433 void NetworkedInput::StopTertiaryAction() {
 434         actions &= ~0x04;
 435 }
 436
 437 }
 438 }