]> git.localhorst.tv Git - blank.git/blobdiff - src/net/net.cpp
move common exceptions to app/error
[blank.git] / src / net / net.cpp
index 98954bf0f168635ac5810b61b70889b2f6cb471e..1dcb9d0e696cbf479f9c427db0f3f5eb12e161cc 100644 (file)
@@ -1,20 +1,16 @@
-#include "Client.hpp"
-#include "ClientConnection.hpp"
+#include "CongestionControl.hpp"
 #include "Connection.hpp"
 #include "ConnectionHandler.hpp"
 #include "io.hpp"
 #include "Packet.hpp"
-#include "Server.hpp"
 
-#include "../app/init.hpp"
-#include "../model/CompositeModel.hpp"
+#include "../app/error.hpp"
+#include "../geometry/const.hpp"
+#include "../model/Model.hpp"
 #include "../world/Entity.hpp"
 #include "../world/EntityState.hpp"
-#include "../world/World.hpp"
 
 #include <cstring>
-#include <iostream>
-#include <glm/gtx/io.hpp>
 
 using namespace std;
 
@@ -30,328 +26,171 @@ constexpr size_t Packet::SpawnEntity::MAX_LEN;
 constexpr size_t Packet::DespawnEntity::MAX_LEN;
 constexpr size_t Packet::EntityUpdate::MAX_LEN;
 constexpr size_t Packet::PlayerCorrection::MAX_LEN;
-
-namespace {
-
-UDPsocket client_bind(Uint16 port) {
-       UDPsocket sock = SDLNet_UDP_Open(port);
-       if (!sock) {
-               throw NetError("SDLNet_UDP_Open");
-       }
-       return sock;
-}
-
-IPaddress client_resolve(const char *host, Uint16 port) {
-       IPaddress addr;
-       if (SDLNet_ResolveHost(&addr, host, port) != 0) {
-               throw NetError("SDLNet_ResolveHost");
+constexpr size_t Packet::ChunkBegin::MAX_LEN;
+constexpr size_t Packet::ChunkData::MAX_LEN;
+constexpr size_t Packet::BlockUpdate::MAX_LEN;
+constexpr size_t Packet::Message::MAX_LEN;
+constexpr size_t Packet::Message::MAX_MESSAGE_LEN;
+
+
+CongestionControl::CongestionControl()
+// I know, I know, it's an estimate (about 20 for IPv4, 48 for IPv6)
+: packet_overhead(20)
+// only sample every eighth packet for measuring RTT
+, sample_skip(8)
+, packets_lost(0)
+, packets_received(0)
+, packet_loss(0.0f)
+, stamp_last(0)
+, rtt(64.0f)
+, next_sample(1000)
+, tx_bytes(0)
+, rx_bytes(0)
+, tx_kbps(0.0f)
+, rx_kbps(0.0f)
+, mode(GOOD)
+// rtt > 75ms or packet loss > 5% is BAD
+, bad_rtt(75.0f)
+, bad_loss(0.05f)
+// rtt > 150ms or packet loss > 15% is UGLY
+, ugly_rtt(150.0f)
+, ugly_loss(0.15f)
+, mode_keep_time(1000) {
+       Uint32 now = SDL_GetTicks();
+       for (Uint32 &s : stamps) {
+               s = now;
+       }
+       next_sample += now;
+       mode_entered = now;
+       mode_reset = now;
+       mode_step = now;
+}
+
+void CongestionControl::PacketSent(uint16_t seq) noexcept {
+       if (!SamplePacket(seq)) {
+               return;
        }
-       return addr;
-}
-
+       stamps[SampleIndex(seq)] = SDL_GetTicks();
+       stamp_last = seq;
 }
 
-Client::Client(const Config &conf)
-: conn(client_resolve(conf.host.c_str(), conf.port))
-, client_sock(client_bind(0))
-, client_pack{ -1, nullptr, 0 } {
-       client_pack.data = new Uint8[sizeof(Packet)];
-       client_pack.maxlen = sizeof(Packet);
-       // establish connection
-       SendPing();
+void CongestionControl::PacketLost(uint16_t seq) noexcept {
+       ++packets_lost;
+       UpdatePacketLoss();
+       UpdateRTT(seq);
 }
 
-Client::~Client() {
-       delete[] client_pack.data;
-       SDLNet_UDP_Close(client_sock);
+void CongestionControl::PacketReceived(uint16_t seq) noexcept {
+       ++packets_received;
+       UpdatePacketLoss();
+       UpdateRTT(seq);
 }
 
-
-void Client::Handle() {
-       int result = SDLNet_UDP_Recv(client_sock, &client_pack);
-       while (result > 0) {
-               HandlePacket(client_pack);
-               result = SDLNet_UDP_Recv(client_sock, &client_pack);
-       }
-       if (result == -1) {
-               // a boo boo happened
-               throw NetError("SDLNet_UDP_Recv");
+void CongestionControl::UpdatePacketLoss() noexcept {
+       unsigned int packets_total = packets_lost + packets_received;
+       if (packets_total >= 256) {
+               packet_loss = float(packets_lost) / float(packets_total);
+               packets_lost = 0;
+               packets_received = 0;
        }
 }
 
-void Client::HandlePacket(const UDPpacket &udp_pack) {
-       if (!conn.Matches(udp_pack.address)) {
-               // packet came from somewhere else, drop
+void CongestionControl::UpdateRTT(uint16_t seq) noexcept {
+       if (!SamplePacket(seq)) return;
+       int16_t diff = int16_t(stamp_last) - int16_t(seq);
+       if (diff < 0 || diff > int(15 * sample_skip)) {
+               // packet outside observed frame
                return;
        }
-       const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
-       if (pack.header.tag != Packet::TAG) {
-               // mistagged packet, drop
-               return;
-       }
-
-       conn.Received(udp_pack);
-}
-
-void Client::Update(int dt) {
-       conn.Update(dt);
-       if (conn.ShouldPing()) {
-               SendPing();
-       }
-}
-
-uint16_t Client::SendPing() {
-       return conn.SendPing(client_pack, client_sock);
+       int cur_rtt = SDL_GetTicks() - stamps[SampleIndex(seq)];
+       rtt += (cur_rtt - rtt) * 0.1f;
 }
 
-uint16_t Client::SendLogin(const string &name) {
-       auto pack = Packet::Make<Packet::Login>(client_pack);
-       pack.WritePlayerName(name);
-       return conn.Send(client_pack, client_sock);
+bool CongestionControl::SamplePacket(uint16_t seq) const noexcept {
+       return seq % sample_skip == 0;
 }
 
-uint16_t Client::SendPlayerUpdate(const Entity &player) {
-       auto pack = Packet::Make<Packet::PlayerUpdate>(client_pack);
-       pack.WritePlayer(player);
-       return conn.Send(client_pack, client_sock);
+size_t CongestionControl::SampleIndex(uint16_t seq) const noexcept {
+       return (seq / sample_skip) % 16;
 }
 
-uint16_t Client::SendPart() {
-       Packet::Make<Packet::Part>(client_pack);
-       return conn.Send(client_pack, client_sock);
+void CongestionControl::PacketIn(const UDPpacket &pack) noexcept {
+       rx_bytes += pack.len + packet_overhead;
+       UpdateStats();
 }
 
-
-ClientConnection::ClientConnection(Server &server, const IPaddress &addr)
-: server(server)
-, conn(addr)
-, player(nullptr)
-, spawns()
-, confirm_wait(0)
-, player_update_pack(0)
-, player_update_timer(1500) {
-       conn.SetHandler(this);
-}
-
-ClientConnection::~ClientConnection() {
-       DetachPlayer();
+void CongestionControl::PacketOut(const UDPpacket &pack) noexcept {
+       tx_bytes += pack.len + packet_overhead;
+       UpdateStats();
 }
 
-void ClientConnection::Update(int dt) {
-       conn.Update(dt);
-       if (Disconnected()) {
+void CongestionControl::UpdateStats() noexcept {
+       Uint32 now = SDL_GetTicks();
+       if (now < next_sample) {
+               // not yet
                return;
        }
-       if (HasPlayer()) {
-               // sync entities
-               auto global_iter = server.GetWorld().Entities().begin();
-               auto global_end = server.GetWorld().Entities().end();
-               auto local_iter = spawns.begin();
-               auto local_end = spawns.end();
-
-               while (global_iter != global_end && local_iter != local_end) {
-                       if (global_iter->ID() == local_iter->entity->ID()) {
-                               // they're the same
-                               if (CanDespawn(*global_iter)) {
-                                       SendDespawn(*local_iter);
-                               } else {
-                                       // update
-                                       SendUpdate(*local_iter);
-                               }
-                               ++global_iter;
-                               ++local_iter;
-                       } else if (global_iter->ID() < local_iter->entity->ID()) {
-                               // global entity was inserted
-                               if (CanSpawn(*global_iter)) {
-                                       auto spawned = spawns.emplace(local_iter, *global_iter);
-                                       SendSpawn(*spawned);
-                               }
-                               ++global_iter;
-                       } else {
-                               // global entity was removed
-                               SendDespawn(*local_iter);
-                               ++local_iter;
-                       }
-               }
-
-               // leftover spawns
-               while (global_iter != global_end) {
-                       if (CanSpawn(*global_iter)) {
-                               spawns.emplace_back(*global_iter);
-                               SendSpawn(spawns.back());
-                       }
-                       ++global_iter;
-               }
-
-               // leftover despawns
-               while (local_iter != local_end) {
-                       SendDespawn(*local_iter);
-                       ++local_iter;
-               }
-
-               CheckPlayerFix();
-       }
-       if (conn.ShouldPing()) {
-               conn.SendPing(server.GetPacket(), server.GetSocket());
-       }
-}
-
-ClientConnection::SpawnStatus::SpawnStatus(Entity &e)
-: entity(&e)
-, spawn_pack(-1)
-, despawn_pack(-1) {
-       entity->Ref();
-}
-
-ClientConnection::SpawnStatus::~SpawnStatus() {
-       entity->UnRef();
-}
-
-bool ClientConnection::CanSpawn(const Entity &e) const noexcept {
-       return
-               &e != player &&
-               !e.Dead() &&
-               manhattan_radius(e.ChunkCoords() - Player().ChunkCoords()) < 7;
-}
-
-bool ClientConnection::CanDespawn(const Entity &e) const noexcept {
-       return
-               e.Dead() ||
-               manhattan_radius(e.ChunkCoords() - Player().ChunkCoords()) > 7;
-}
-
-void ClientConnection::SendSpawn(SpawnStatus &status) {
-       // don't double spawn
-       if (status.spawn_pack != -1) return;
-
-       auto pack = Packet::Make<Packet::SpawnEntity>(server.GetPacket());
-       pack.WriteEntity(*status.entity);
-       status.spawn_pack = conn.Send(server.GetPacket(), server.GetSocket());
-       ++confirm_wait;
+       tx_kbps = float(tx_bytes) * (1.0f / 1024.0f);
+       rx_kbps = float(rx_bytes) * (1.0f / 1024.0f);
+       tx_bytes = 0;
+       rx_bytes = 0;
+       next_sample += 1000;
+       UpdateMode();
 }
 
-void ClientConnection::SendDespawn(SpawnStatus &status) {
-       // don't double despawn
-       if (status.despawn_pack != -1) return;
-
-       auto pack = Packet::Make<Packet::DespawnEntity>(server.GetPacket());
-       pack.WriteEntityID(status.entity->ID());
-       status.despawn_pack = conn.Send(server.GetPacket(), server.GetSocket());
-       ++confirm_wait;
-}
-
-void ClientConnection::SendUpdate(SpawnStatus &status) {
-       // don't send updates while spawn not ack'd or despawn sent
-       if (status.spawn_pack != -1 || status.despawn_pack != -1) return;
-
-       // TODO: pack entity updates
-       auto pack = Packet::Make<Packet::EntityUpdate>(server.GetPacket());
-       pack.WriteEntityCount(1);
-       pack.WriteEntity(*status.entity, 0);
-       server.GetPacket().len = Packet::EntityUpdate::GetSize(1);
-       conn.Send(server.GetPacket(), server.GetSocket());
-}
-
-void ClientConnection::CheckPlayerFix() {
-       // check always succeeds for now ;)
-       auto pack = Packet::Make<Packet::PlayerCorrection>(server.GetPacket());
-       pack.WritePacketSeq(player_update_pack);
-       pack.WritePlayer(Player());
-       conn.Send(server.GetPacket(), server.GetSocket());
-}
-
-void ClientConnection::AttachPlayer(Entity &new_player) {
-       DetachPlayer();
-       player = &new_player;
-       player->Ref();
-       cout << "player \"" << player->Name() << "\" joined" << endl;
-}
-
-void ClientConnection::DetachPlayer() {
-       if (!player) return;
-       player->Kill();
-       player->UnRef();
-       cout << "player \"" << player->Name() << "\" left" << endl;
-       player = nullptr;
+void CongestionControl::UpdateMode() noexcept {
+       Mode now_mode = Conditions();
+       if (now_mode > mode) {
+               ChangeMode(now_mode);
+       } else if (now_mode < mode) {
+               CheckUpgrade(now_mode);
+       } else {
+               KeepMode();
+       }
 }
 
-void ClientConnection::OnPacketReceived(uint16_t seq) {
-       if (!confirm_wait) return;
-       for (auto iter = spawns.begin(), end = spawns.end(); iter != end; ++iter) {
-               if (seq == iter->spawn_pack) {
-                       iter->spawn_pack = -1;
-                       --confirm_wait;
-                       return;
-               }
-               if (seq == iter->despawn_pack) {
-                       spawns.erase(iter);
-                       --confirm_wait;
-                       return;
-               }
+void CongestionControl::CheckUpgrade(Mode m) noexcept {
+       Uint32 now = SDL_GetTicks();
+       Uint32 time_in_mode = now - mode_entered;
+       if (time_in_mode < mode_keep_time) {
+               return;
        }
+       ChangeMode(m);
 }
 
-void ClientConnection::OnPacketLost(uint16_t seq) {
-       if (!confirm_wait) return;
-       for (SpawnStatus &status : spawns) {
-               if (seq == status.spawn_pack) {
-                       status.spawn_pack = -1;
-                       --confirm_wait;
-                       SendSpawn(status);
-                       return;
-               }
-               if (seq == status.despawn_pack) {
-                       status.despawn_pack = -1;
-                       --confirm_wait;
-                       SendDespawn(status);
-                       return;
+void CongestionControl::ChangeMode(Mode m) noexcept {
+       Uint32 now = SDL_GetTicks();
+       if (m > mode) {
+               // changed to worse mode
+               // if we spent less than 10 seconds in better mode
+               // double keep time till up to 64 seconds
+               if (now - mode_entered < 10000) {
+                       if (mode_keep_time < 64000) {
+                               mode_keep_time *= 2;
+                       }
                }
        }
+       mode = m;
+       mode_entered = now;
+       mode_reset = mode_entered;
 }
 
-void ClientConnection::On(const Packet::Login &pack) {
-       string name;
-       pack.ReadPlayerName(name);
-
-       Entity *new_player = server.GetWorld().AddPlayer(name).entity;
-
-       if (new_player) {
-               // success!
-               AttachPlayer(*new_player);
-               cout << "accepted login from player \"" << name << '"' << endl;
-               auto response = Packet::Make<Packet::Join>(server.GetPacket());
-               response.WritePlayer(*new_player);
-               response.WriteWorldName(server.GetWorld().Name());
-               conn.Send(server.GetPacket(), server.GetSocket());
-               // set up update tracking
-               player_update_pack = pack.Seq();
-               player_update_timer.Reset();
-               player_update_timer.Start();
-       } else {
-               // aw no :(
-               cout << "rejected login from player \"" << name << '"' << endl;
-               Packet::Make<Packet::Part>(server.GetPacket());
-               conn.Send(server.GetPacket(), server.GetSocket());
-               conn.Close();
+void CongestionControl::KeepMode() noexcept {
+       mode_reset = SDL_GetTicks();
+       // if in good mode for 10 seconds, halve keep time till down to one second
+       if (mode == GOOD && mode_keep_time > 1000 && mode_step - mode_reset > 10000) {
+               mode_keep_time /= 2;
+               mode_step = mode_reset;
        }
 }
 
-void ClientConnection::On(const Packet::Part &) {
-       conn.Close();
-}
-
-void ClientConnection::On(const Packet::PlayerUpdate &pack) {
-       if (!HasPlayer()) return;
-       int pack_diff = int16_t(pack.Seq()) - int16_t(player_update_pack);
-       bool overdue = player_update_timer.HitOnce();
-       player_update_timer.Reset();
-       if (pack_diff > 0 || overdue) {
-               player_update_pack = pack.Seq();
-               // TODO: do client input validation here
-               EntityState new_state;
-               pack.ReadPlayerState(new_state);
-               Player().Velocity(new_state.velocity);
-               Player().Orientation(new_state.orient);
+CongestionControl::Mode CongestionControl::Conditions() const noexcept {
+       if (rtt > ugly_rtt || packet_loss > ugly_loss) {
+               return UGLY;
+       } else if (rtt > bad_rtt || packet_loss > bad_loss) {
+               return BAD;
+       } else {
+               return GOOD;
        }
 }
 
@@ -359,7 +198,9 @@ void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 Connection::Connection(const IPaddress &addr)
 : handler(nullptr)
 , addr(addr)
-, send_timer(500)
+// make sure a packet is sent at least every 50ms since packets contains
+// acks that the remote end will use to measure RTT
+, send_timer(50)
 , recv_timer(10000)
 , ctrl_out{ 0, 0xFFFF, 0xFFFFFFFF }
 , ctrl_in{ 0, 0xFFFF, 0xFFFFFFFF }
@@ -410,6 +251,11 @@ uint16_t Connection::Send(UDPpacket &udp_pack, UDPsocket sock) {
                throw NetError("SDLNet_UDP_Send");
        }
 
+       if (HasHandler()) {
+               Handler().PacketOut(udp_pack);
+               Handler().PacketSent(seq);
+       }
+
        FlagSend();
        return seq;
 }
@@ -437,6 +283,7 @@ void Connection::Received(const UDPpacket &udp_pack) {
        }
 
        Packet::TControl ctrl_new = pack.header.ctrl;
+       Handler().PacketIn(udp_pack);
        Handler().Handle(udp_pack);
 
        if (diff > 0) {
@@ -447,14 +294,14 @@ void Connection::Received(const UDPpacket &udp_pack) {
                if (diff > 0) {
                        for (int i = 0; i < diff; ++i) {
                                if (i > 32 || (i < 32 && (ctrl_in.hist & (1 << (31 - i))) == 0)) {
-                                       Handler().OnPacketLost(ctrl_in.ack - 32 + i);
+                                       Handler().PacketLost(ctrl_in.ack - 32 + i);
                                }
                        }
                }
                // check for newly ack'd packets
-               for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); ++s) {
+               for (uint16_t s = ctrl_new.AckBegin(); s != ctrl_new.AckEnd(); --s) {
                        if (ctrl_new.Acks(s) && !ctrl_in.Acks(s)) {
-                               Handler().OnPacketReceived(s);
+                               Handler().PacketReceived(s);
                        }
                }
                ctrl_in = ctrl_new;
@@ -474,6 +321,34 @@ uint16_t Connection::SendPing(UDPpacket &udp_pack, UDPsocket sock) {
 }
 
 
+ConnectionHandler::ConnectionHandler()
+: cc() {
+
+}
+
+void ConnectionHandler::PacketSent(uint16_t seq) noexcept {
+       cc.PacketSent(seq);
+}
+
+void ConnectionHandler::PacketLost(uint16_t seq) {
+       OnPacketLost(seq);
+       cc.PacketLost(seq);
+}
+
+void ConnectionHandler::PacketReceived(uint16_t seq) {
+       OnPacketReceived(seq);
+       cc.PacketReceived(seq);
+}
+
+void ConnectionHandler::PacketIn(const UDPpacket &pack) noexcept {
+       cc.PacketIn(pack);
+}
+
+void ConnectionHandler::PacketOut(const UDPpacket &pack) noexcept {
+       cc.PacketOut(pack);
+}
+
+
 ostream &operator <<(ostream &out, const IPaddress &addr) {
        const unsigned char *host = reinterpret_cast<const unsigned char *>(&addr.host);
        out << int(host[0])
@@ -507,6 +382,14 @@ const char *Packet::Type2String(uint8_t t) noexcept {
                        return "EntityUpdate";
                case PlayerCorrection::TYPE:
                        return "PlayerCorrection";
+               case ChunkBegin::TYPE:
+                       return "ChunkBegin";
+               case ChunkData::TYPE:
+                       return "ChunkData";
+               case BlockUpdate::TYPE:
+                       return "BlockUpdate";
+               case Message::TYPE:
+                       return "Message";
                default:
                        return "Unknown";
        }
@@ -550,6 +433,175 @@ void Packet::Payload::ReadString(string &dst, size_t off, size_t maxlen) const n
        }
 }
 
+void Packet::Payload::Write(const glm::quat &val, size_t off) noexcept {
+       // find the largest component
+       float largest = 0.0f;
+       int largest_index = -1;
+       for (int i = 0; i < 4; ++i) {
+               float iabs = abs(val[i]);
+               if (iabs > largest) {
+                       largest = iabs;
+                       largest_index = i;
+               }
+       }
+       // make sure it's positive
+       const glm::quat q(val[largest_index] < 0.0f ? -val : val);
+       // move index to the two most significant bits
+       uint64_t packed = uint64_t(largest_index) << 62;
+       // we have to map from [-0.7072,0.7072] to [-524287,524287] and move into positive range
+       constexpr float conv = 524287.0f / 0.7072f;
+       // if largest is 1, the other three are 0
+       // precision of comparison is the interval of our mapping
+       if (abs(1.0 - largest) < (1.0f / conv)) {
+               packed |= 0x7FFFF7FFFF7FFFF;
+       } else {
+               // pack the three smaller components into 20bit ints each
+               int shift = 40;
+               for (int i = 0; i < 4; ++i) {
+                       if (i != largest_index) {
+                               packed |= uint64_t(int(q[i] * conv) + 524287) << shift;
+                               shift -= 20;
+                       }
+               }
+       }
+       // and write it out
+       Write(packed, off);
+}
+
+void Packet::Payload::Read(glm::quat &val, size_t off) const noexcept {
+       // extract the 8 byte packed value
+       uint64_t packed = 0;
+       Read(packed, off);
+       // two most significant bits are the index of the largest (omitted) component
+       int largest_index = packed >> 62;
+       // if all other three are 0, largest is 1 and we can omit the conversion
+       if ((packed & 0xFFFFFFFFFFFFFFF) == 0x7FFFF7FFFF7FFFF) {
+               val = { 0.0f, 0.0f, 0.0f, 0.0f };
+               val[largest_index] = 1.0f;
+               return;
+       }
+       // we have to map from [-524287,524287] to [-0.7072,0.7072]
+       constexpr float conv = 0.7072f / 524287.0f;
+       int shift = 40;
+       for (int i = 0; i < 4; ++i) {
+               if (i != largest_index) {
+                       val[i] = float(int((packed >> shift) & 0xFFFFF) - 524287) * conv;
+                       shift -= 20;
+               } else {
+                       // set to zero so the length of the other three can be determined
+                       val[i] = 0.0f;
+               }
+       }
+       // omitted component squared is 1 - length squared of others
+       val[largest_index] = sqrt(1.0f - glm::length2(val));
+       // and already normalized
+}
+
+void Packet::Payload::Write(const EntityState &state, size_t off) noexcept {
+       Write(state.pos.chunk, off);
+       WritePackU(state.pos.block * (1.0f / ExactLocation::fscale), off + 12);
+       Write(state.velocity, off + 18);
+       Write(state.orient, off + 30);
+       WritePackN(state.pitch * PI_0p5_inv, off + 38);
+       WritePackN(state.yaw * PI_inv, off + 40);
+}
+
+void Packet::Payload::Read(EntityState &state, size_t off) const noexcept {
+       Read(state.pos.chunk, off);
+       ReadPackU(state.pos.block, off + 12);
+       Read(state.velocity, off + 18);
+       Read(state.orient, off + 30);
+       ReadPackN(state.pitch, off + 38);
+       ReadPackN(state.yaw, off + 40);
+       state.pos.block *= ExactLocation::fscale;
+       state.pitch *= PI_0p5;
+       state.yaw *= PI;
+}
+
+void Packet::Payload::Write(const EntityState &state, const glm::ivec3 &base, size_t off) noexcept {
+       WritePackB(state.pos.chunk - base, off);
+       WritePackU(state.pos.block * (1.0f / ExactLocation::fscale), off + 3);
+       Write(state.velocity, off + 9);
+       Write(state.orient, off + 21);
+       WritePackN(state.pitch * PI_0p5_inv, off + 29);
+       WritePackN(state.yaw * PI_inv, off + 31);
+}
+
+void Packet::Payload::Read(EntityState &state, const glm::ivec3 &base, size_t off) const noexcept {
+       ReadPackB(state.pos.chunk, off);
+       ReadPackU(state.pos.block, off + 3);
+       Read(state.velocity, off + 9);
+       Read(state.orient, off + 21);
+       ReadPackN(state.pitch, off + 29);
+       ReadPackN(state.yaw, off + 31);
+       state.pos.chunk += base;
+       state.pos.block *= ExactLocation::fscale;
+       state.pitch *= PI_0p5;
+       state.yaw *= PI;
+}
+
+void Packet::Payload::WritePackB(const glm::ivec3 &val, size_t off) noexcept {
+       Write(int8_t(val.x), off);
+       Write(int8_t(val.y), off + 1);
+       Write(int8_t(val.z), off + 2);
+}
+
+void Packet::Payload::ReadPackB(glm::ivec3 &val, size_t off) const noexcept {
+       int8_t conv = 0;
+       Read(conv, off);
+       val.x = conv;
+       Read(conv, off + 1);
+       val.y = conv;
+       Read(conv, off + 2);
+       val.z = conv;
+}
+
+void Packet::Payload::WritePackN(float val, size_t off) noexcept {
+       int16_t raw = glm::clamp(glm::round(val * 32767.0f), -32767.0f, 32767.0f);
+       Write(raw, off);
+}
+
+void Packet::Payload::ReadPackN(float &val, size_t off) const noexcept {
+       int16_t raw = 0;
+       Read(raw, off);
+       val = raw * (1.0f/32767.0f);
+}
+
+void Packet::Payload::WritePackN(const glm::vec3 &val, size_t off) noexcept {
+       WritePackN(val.x, off);
+       WritePackN(val.y, off + 2);
+       WritePackN(val.z, off + 4);
+}
+
+void Packet::Payload::ReadPackN(glm::vec3 &val, size_t off) const noexcept {
+       ReadPackN(val.x, off);
+       ReadPackN(val.y, off + 2);
+       ReadPackN(val.z, off + 4);
+}
+
+void Packet::Payload::WritePackU(float val, size_t off) noexcept {
+       uint16_t raw = glm::clamp(glm::round(val * 65535.0f), 0.0f, 65535.0f);
+       Write(raw, off);
+}
+
+void Packet::Payload::ReadPackU(float &val, size_t off) const noexcept {
+       uint16_t raw = 0;
+       Read(raw, off);
+       val = raw * (1.0f/65535.0f);
+}
+
+void Packet::Payload::WritePackU(const glm::vec3 &val, size_t off) noexcept {
+       WritePackU(val.x, off);
+       WritePackU(val.y, off + 2);
+       WritePackU(val.z, off + 4);
+}
+
+void Packet::Payload::ReadPackU(glm::vec3 &val, size_t off) const noexcept {
+       ReadPackU(val.x, off);
+       ReadPackU(val.y, off + 2);
+       ReadPackU(val.z, off + 4);
+}
+
 
 void Packet::Login::WritePlayerName(const string &name) noexcept {
        WriteString(name, 0, 32);
@@ -573,21 +625,45 @@ void Packet::Join::ReadPlayerState(EntityState &state) const noexcept {
 }
 
 void Packet::Join::WriteWorldName(const string &name) noexcept {
-       WriteString(name, 68, 32);
+       WriteString(name, 46, 32);
 }
 
 void Packet::Join::ReadWorldName(string &name) const noexcept {
-       ReadString(name, 68, 32);
+       ReadString(name, 46, 32);
 }
 
-void Packet::PlayerUpdate::WritePlayer(const Entity &player) noexcept {
-       Write(player.GetState(), 0);
+void Packet::PlayerUpdate::WritePredictedState(const EntityState &state) noexcept {
+       Write(state, 0);
 }
 
-void Packet::PlayerUpdate::ReadPlayerState(EntityState &state) const noexcept {
+void Packet::PlayerUpdate::ReadPredictedState(EntityState &state) const noexcept {
        Read(state, 0);
 }
 
+void Packet::PlayerUpdate::WriteMovement(const glm::vec3 &mov) noexcept {
+       WritePackN(mov, 42);
+}
+
+void Packet::PlayerUpdate::ReadMovement(glm::vec3 &mov) const noexcept {
+       ReadPackN(mov, 42);
+}
+
+void Packet::PlayerUpdate::WriteActions(uint8_t actions) noexcept {
+       Write(actions, 48);
+}
+
+void Packet::PlayerUpdate::ReadActions(uint8_t &actions) const noexcept {
+       Read(actions, 48);
+}
+
+void Packet::PlayerUpdate::WriteSlot(uint8_t slot) noexcept {
+       Write(slot, 49);
+}
+
+void Packet::PlayerUpdate::ReadSlot(uint8_t &slot) const noexcept {
+       Read(slot, 49);
+}
+
 void Packet::SpawnEntity::WriteEntity(const Entity &e) noexcept {
        Write(e.ID(), 0);
        if (e.GetModel()) {
@@ -596,20 +672,20 @@ void Packet::SpawnEntity::WriteEntity(const Entity &e) noexcept {
                Write(uint32_t(0), 4);
        }
        Write(e.GetState(), 8);
-       Write(e.Bounds(), 72);
+       Write(e.Bounds(), 50);
        uint32_t flags = 0;
        if (e.WorldCollidable()) {
                flags |= 1;
        }
-       Write(flags, 96);
-       WriteString(e.Name(), 100, 32);
+       Write(flags, 74);
+       WriteString(e.Name(), 78, 32);
 }
 
 void Packet::SpawnEntity::ReadEntityID(uint32_t &id) const noexcept {
        Read(id, 0);
 }
 
-void Packet::SpawnEntity::ReadSkeletonID(uint32_t &id) const noexcept {
+void Packet::SpawnEntity::ReadModelID(uint32_t &id) const noexcept {
        Read(id, 4);
 }
 
@@ -620,9 +696,9 @@ void Packet::SpawnEntity::ReadEntity(Entity &e) const noexcept {
        string name;
 
        Read(state, 8);
-       Read(bounds, 72);
-       Read(flags, 96);
-       ReadString(name, 100, 32);
+       Read(bounds, 50);
+       Read(flags, 74);
+       ReadString(name, 78, 32);
 
        e.SetState(state);
        e.Bounds(bounds);
@@ -646,20 +722,29 @@ void Packet::EntityUpdate::ReadEntityCount(uint32_t &count) const noexcept {
        Read(count, 0);
 }
 
-void Packet::EntityUpdate::WriteEntity(const Entity &entity, uint32_t num) noexcept {
-       uint32_t off = 4 + (num * 64);
+void Packet::EntityUpdate::WriteChunkBase(const glm::ivec3 &base) noexcept {
+       Write(base, 4);
+}
+
+void Packet::EntityUpdate::ReadChunkBase(glm::ivec3 &base) const noexcept {
+       Read(base, 4);
+}
+
+void Packet::EntityUpdate::WriteEntity(const Entity &entity, const glm::ivec3 &base, uint32_t num) noexcept {
+       uint32_t off = GetSize(num);
 
        Write(entity.ID(), off);
-       Write(entity.GetState(), off + 4);
+       Write(entity.GetState(), base, off + 4);
 }
 
 void Packet::EntityUpdate::ReadEntityID(uint32_t &id, uint32_t num) const noexcept {
-       Read(id, 4 + (num * 64));
+       uint32_t off = GetSize(num);
+       Read(id, off);
 }
 
-void Packet::EntityUpdate::ReadEntityState(EntityState &state, uint32_t num) const noexcept {
-       uint32_t off = 4 + (num * 64);
-       Read(state, off + 4);
+void Packet::EntityUpdate::ReadEntityState(EntityState &state, const glm::ivec3 &base, uint32_t num) const noexcept {
+       uint32_t off = GetSize(num);
+       Read(state, base, off + 4);
 }
 
 void Packet::PlayerCorrection::WritePacketSeq(std::uint16_t s) noexcept {
@@ -678,6 +763,132 @@ void Packet::PlayerCorrection::ReadPlayerState(EntityState &state) const noexcep
        Read(state, 2);
 }
 
+void Packet::ChunkBegin::WriteTransmissionId(uint32_t id) noexcept {
+       Write(id, 0);
+}
+
+void Packet::ChunkBegin::ReadTransmissionId(uint32_t &id) const noexcept {
+       Read(id, 0);
+}
+
+void Packet::ChunkBegin::WriteFlags(uint32_t f) noexcept {
+       Write(f, 4);
+}
+
+void Packet::ChunkBegin::ReadFlags(uint32_t &f) const noexcept {
+       Read(f, 4);
+}
+
+void Packet::ChunkBegin::WriteChunkCoords(const glm::ivec3 &pos) noexcept {
+       Write(pos, 8);
+}
+
+void Packet::ChunkBegin::ReadChunkCoords(glm::ivec3 &pos) const noexcept {
+       Read(pos, 8);
+}
+
+void Packet::ChunkBegin::WriteDataSize(uint32_t s) noexcept {
+       Write(s, 20);
+}
+
+void Packet::ChunkBegin::ReadDataSize(uint32_t &s) const noexcept {
+       Read(s, 20);
+}
+
+void Packet::ChunkData::WriteTransmissionId(uint32_t id) noexcept {
+       Write(id, 0);
+}
+
+void Packet::ChunkData::ReadTransmissionId(uint32_t &id) const noexcept {
+       Read(id, 0);
+}
+
+void Packet::ChunkData::WriteDataOffset(uint32_t o) noexcept {
+       Write(o, 4);
+}
+
+void Packet::ChunkData::ReadDataOffset(uint32_t &o) const noexcept {
+       Read(o, 4);
+}
+
+void Packet::ChunkData::WriteDataSize(uint32_t s) noexcept {
+       Write(s, 8);
+}
+
+void Packet::ChunkData::ReadDataSize(uint32_t &s) const noexcept {
+       Read(s, 8);
+}
+
+void Packet::ChunkData::WriteData(const uint8_t *d, size_t l) noexcept {
+       size_t len = min(length - 12, l);
+       memcpy(&data[12], d, len);
+}
+
+void Packet::ChunkData::ReadData(uint8_t *d, size_t l) const noexcept {
+       size_t len = min(length - 12, l);
+       memcpy(d, &data[12], len);
+}
+
+void Packet::BlockUpdate::WriteChunkCoords(const glm::ivec3 &coords) noexcept {
+       Write(coords, 0);
+}
+
+void Packet::BlockUpdate::ReadChunkCoords(glm::ivec3 &coords) const noexcept {
+       Read(coords, 0);
+}
+
+void Packet::BlockUpdate::WriteBlockCount(uint32_t count) noexcept {
+       Write(count, 12);
+}
+
+void Packet::BlockUpdate::ReadBlockCount(uint32_t &count) const noexcept {
+       Read(count, 12);
+}
+
+void Packet::BlockUpdate::WriteIndex(uint16_t index, uint32_t num) noexcept {
+       uint32_t off = GetSize(num);
+       Write(index, off);
+}
+
+void Packet::BlockUpdate::ReadIndex(uint16_t &index, uint32_t num) const noexcept {
+       uint32_t off = GetSize(num);
+       Read(index, off);
+}
+
+void Packet::BlockUpdate::WriteBlock(const Block &block, uint32_t num) noexcept {
+       uint32_t off = GetSize(num) + 2;
+       Write(block, off);
+}
+
+void Packet::BlockUpdate::ReadBlock(Block &block, uint32_t num) const noexcept {
+       uint32_t off = GetSize(num) + 2;
+       Read(block, off);
+}
+
+void Packet::Message::WriteType(uint8_t type) noexcept {
+       Write(type, 0);
+}
+
+void Packet::Message::ReadType(uint8_t &type) const noexcept {
+       Read(type, 0);
+}
+
+void Packet::Message::WriteReferral(uint32_t ref) noexcept {
+       Write(ref, 1);
+}
+
+void Packet::Message::ReadReferral(uint32_t &ref) const noexcept {
+       Read(ref, 1);
+}
+
+void Packet::Message::WriteMessage(const string &msg) noexcept {
+       WriteString(msg, 5, MAX_MESSAGE_LEN);
+}
+
+void Packet::Message::ReadMessage(string &msg) const noexcept {
+       ReadString(msg, 5, MAX_MESSAGE_LEN);
+}
+
 
 void ConnectionHandler::Handle(const UDPpacket &udp_pack) {
        const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
@@ -709,79 +920,22 @@ void ConnectionHandler::Handle(const UDPpacket &udp_pack) {
                case Packet::PlayerCorrection::TYPE:
                        On(Packet::As<Packet::PlayerCorrection>(udp_pack));
                        break;
+               case Packet::ChunkBegin::TYPE:
+                       On(Packet::As<Packet::ChunkBegin>(udp_pack));
+                       break;
+               case Packet::ChunkData::TYPE:
+                       On(Packet::As<Packet::ChunkData>(udp_pack));
+                       break;
+               case Packet::BlockUpdate::TYPE:
+                       On(Packet::As<Packet::BlockUpdate>(udp_pack));
+                       break;
+               case Packet::Message::TYPE:
+                       On(Packet::As<Packet::Message>(udp_pack));
+                       break;
                default:
                        // drop unknown or unhandled packets
                        break;
        }
 }
 
-
-Server::Server(const Config &conf, World &world)
-: serv_sock(nullptr)
-, serv_pack{ -1, nullptr, 0 }
-, clients()
-, world(world) {
-       serv_sock = SDLNet_UDP_Open(conf.port);
-       if (!serv_sock) {
-               throw NetError("SDLNet_UDP_Open");
-       }
-
-       serv_pack.data = new Uint8[sizeof(Packet)];
-       serv_pack.maxlen = sizeof(Packet);
-}
-
-Server::~Server() {
-       delete[] serv_pack.data;
-       SDLNet_UDP_Close(serv_sock);
-}
-
-
-void Server::Handle() {
-       int result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
-       while (result > 0) {
-               HandlePacket(serv_pack);
-               result = SDLNet_UDP_Recv(serv_sock, &serv_pack);
-       }
-       if (result == -1) {
-               // a boo boo happened
-               throw NetError("SDLNet_UDP_Recv");
-       }
-}
-
-void Server::HandlePacket(const UDPpacket &udp_pack) {
-       if (udp_pack.len < int(sizeof(Packet::Header))) {
-               // packet too small, drop
-               return;
-       }
-       const Packet &pack = *reinterpret_cast<const Packet *>(udp_pack.data);
-       if (pack.header.tag != Packet::TAG) {
-               // mistagged packet, drop
-               return;
-       }
-
-       ClientConnection &client = GetClient(udp_pack.address);
-       client.GetConnection().Received(udp_pack);
-}
-
-ClientConnection &Server::GetClient(const IPaddress &addr) {
-       for (ClientConnection &client : clients) {
-               if (client.Matches(addr)) {
-                       return client;
-               }
-       }
-       clients.emplace_back(*this, addr);
-       return clients.back();
-}
-
-void Server::Update(int dt) {
-       for (list<ClientConnection>::iterator client(clients.begin()), end(clients.end()); client != end;) {
-               client->Update(dt);
-               if (client->Disconnected()) {
-                       client = clients.erase(client);
-               } else {
-                       ++client;
-               }
-       }
-}
-
 }