From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Fri, 11 Sep 2015 14:59:35 +0000 (+0200)
Subject: better control over entity update transmission
X-Git-Url: https://git.localhorst.tv/?a=commitdiff_plain;h=68f47f2824989b21ff9a480a367a6d0a41804f41;p=blank.git

better control over entity update transmission
---

diff --git a/src/ai/Spawner.cpp b/src/ai/Spawner.cpp
index 13a8f52..eaaa1f8 100644
--- a/src/ai/Spawner.cpp
+++ b/src/ai/Spawner.cpp
@@ -120,7 +120,6 @@ void Spawner::Spawn(Entity &reference, const glm::ivec3 &chunk, const glm::vec3
 	rot.z *= (random.Next<unsigned short>() % 1024);
 
 	Entity &e = world.AddEntity();
-	e.Name("spawned");
 	e.Position(chunk, pos);
 	e.Bounds({ { -0.5f, -0.5f, -0.5f }, { 0.5f, 0.5f, 0.5f } });
 	e.WorldCollidable(true);
@@ -129,8 +128,10 @@ void Spawner::Spawn(Entity &reference, const glm::ivec3 &chunk, const glm::vec3
 	Controller *ctrl;
 	if (random()) {
 		ctrl = new RandomWalk(e, random.Next<std::uint64_t>());
+		e.Name("spawned walker");
 	} else {
 		ctrl = new Chaser(world, e, reference);
+		e.Name("spawned chaser");
 	}
 	controllers.emplace_back(ctrl);
 }
diff --git a/src/ai/ai.cpp b/src/ai/ai.cpp
index a1abfdc..d50aee5 100644
--- a/src/ai/ai.cpp
+++ b/src/ai/ai.cpp
@@ -28,6 +28,11 @@ Chaser::~Chaser() {
 }
 
 void Chaser::Update(int dt) {
+	if (Target().Dead()) {
+		Controlled().Kill();
+		return;
+	}
+
 	glm::vec3 diff(Target().AbsoluteDifference(Controlled()));
 	float dist = length(diff);
 	if (dist < std::numeric_limits<float>::epsilon()) {
diff --git a/src/client/MasterState.hpp b/src/client/MasterState.hpp
index 8eeadf0..61069dc 100644
--- a/src/client/MasterState.hpp
+++ b/src/client/MasterState.hpp
@@ -7,6 +7,7 @@
 #include "../net/Client.hpp"
 #include "../net/ConnectionHandler.hpp"
 
+#include <map>
 #include <memory>
 
 
@@ -55,6 +56,13 @@ public:
 	void On(const Packet::DespawnEntity &) override;
 	void On(const Packet::EntityUpdate &) override;
 
+private:
+	/// flag entity as updated by given packet
+	/// returns false if the update should be ignored
+	bool UpdateEntity(std::uint32_t id, std::uint16_t seq);
+	/// drop update information or given entity
+	void ClearEntity(std::uint32_t id);
+
 private:
 	Environment &env;
 	World::Config world_conf;
@@ -67,6 +75,13 @@ private:
 
 	int login_packet;
 
+	struct UpdateStatus {
+		std::uint16_t last_packet;
+		int last_update;
+	};
+	std::map<std::uint32_t, UpdateStatus> update_status;
+	IntervalTimer update_timer;
+
 };
 
 }
diff --git a/src/client/client.cpp b/src/client/client.cpp
index 96c30f5..757bc3a 100644
--- a/src/client/client.cpp
+++ b/src/client/client.cpp
@@ -137,8 +137,11 @@ MasterState::MasterState(
 , state()
 , client(cc)
 , init_state(*this)
-, login_packet(-1) {
+, login_packet(-1)
+, update_status()
+, update_timer(16) {
 	client.GetConnection().SetHandler(this);
+	update_timer.Start();
 }
 
 void MasterState::Quit() {
@@ -161,6 +164,7 @@ void MasterState::Handle(const SDL_Event &event) {
 
 
 void MasterState::Update(int dt) {
+	update_timer.Update(dt);
 	client.Handle();
 	client.Update(dt);
 }
@@ -194,6 +198,8 @@ void MasterState::On(const Packet::Join &pack) {
 	} else {
 		// joining game
 		cout << "joined game \"" << world_conf.name << '"' << endl;
+		// server received our login
+		login_packet = -1;
 	}
 
 	uint32_t player_id;
@@ -225,20 +231,16 @@ void MasterState::On(const Packet::SpawnEntity &pack) {
 	}
 	uint32_t entity_id;
 	pack.ReadEntityID(entity_id);
-	Entity *entity = state->GetWorld().AddEntity(entity_id);
-	if (!entity) {
-		cout << "entity ID inconsistency" << endl;
-		Quit();
-		return;
-	}
-	pack.ReadEntity(*entity);
+	Entity &entity = state->GetWorld().ForceAddEntity(entity_id);
+	UpdateEntity(entity_id, pack.Seq());
+	pack.ReadEntity(entity);
 	uint32_t skel_id;
 	pack.ReadSkeletonID(skel_id);
 	CompositeModel *skel = state->GetSkeletons().ByID(skel_id);
 	if (skel) {
-		skel->Instantiate(entity->GetModel());
+		skel->Instantiate(entity.GetModel());
 	}
-	cout << "spawned entity " << entity->Name() << " at " << entity->AbsolutePosition() << endl;
+	cout << "spawned entity " << entity.Name() << " at " << entity.AbsolutePosition() << endl;
 }
 
 void MasterState::On(const Packet::DespawnEntity &pack) {
@@ -249,6 +251,7 @@ void MasterState::On(const Packet::DespawnEntity &pack) {
 	}
 	uint32_t entity_id;
 	pack.ReadEntityID(entity_id);
+	ClearEntity(entity_id);
 	for (Entity &entity : state->GetWorld().Entities()) {
 		if (entity.ID() == entity_id) {
 			entity.Kill();
@@ -283,10 +286,35 @@ void MasterState::On(const Packet::EntityUpdate &pack) {
 			return;
 		}
 		if (world_iter->ID() == entity_id) {
-			pack.ReadEntity(*world_iter, i);
+			if (UpdateEntity(entity_id, pack.Seq())) {
+				pack.ReadEntity(*world_iter, i);
+			}
 		}
 	}
 }
 
+bool MasterState::UpdateEntity(uint32_t entity_id, uint16_t seq) {
+	auto entry = update_status.find(entity_id);
+	if (entry == update_status.end()) {
+		update_status.emplace(entity_id, UpdateStatus{ seq, update_timer.Elapsed() });
+		return true;
+	}
+
+	int pack_diff = int16_t(seq) - int16_t(entry->second.last_packet);
+	int time_diff = update_timer.Elapsed() - entry->second.last_update;
+	entry->second.last_update = update_timer.Elapsed();
+
+	if (pack_diff > 0 || time_diff > 1500) {
+		entry->second.last_packet = seq;
+		return true;
+	} else {
+		return false;
+	}
+}
+
+void MasterState::ClearEntity(uint32_t entity_id) {
+	update_status.erase(entity_id);
+}
+
 }
 }
diff --git a/src/net/Client.hpp b/src/net/Client.hpp
index 2848aed..ee848c0 100644
--- a/src/net/Client.hpp
+++ b/src/net/Client.hpp
@@ -2,6 +2,7 @@
 #define BLANK_NET_CLIENT_HPP_
 
 #include "Connection.hpp"
+#include "../app/IntervalTimer.hpp"
 
 #include <string>
 #include <SDL_net.h>
@@ -33,7 +34,8 @@ public:
 	std::uint16_t SendPing();
 	std::uint16_t SendLogin(const std::string &);
 	std::uint16_t SendPart();
-	std::uint16_t SendPlayerUpdate(const Entity &);
+	// this may not send the update at all, in which case it returns -1
+	int SendPlayerUpdate(const Entity &);
 
 private:
 	void HandlePacket(const UDPpacket &);
@@ -42,6 +44,7 @@ private:
 	Connection conn;
 	UDPsocket client_sock;
 	UDPpacket client_pack;
+	IntervalTimer update_timer;
 
 };
 
diff --git a/src/net/ClientConnection.hpp b/src/net/ClientConnection.hpp
index fb6420a..c375409 100644
--- a/src/net/ClientConnection.hpp
+++ b/src/net/ClientConnection.hpp
@@ -3,6 +3,7 @@
 
 #include "Connection.hpp"
 #include "ConnectionHandler.hpp"
+#include "../app/IntervalTimer.hpp"
 
 #include <list>
 #include <SDL_net.h>
@@ -67,6 +68,8 @@ private:
 	Entity *player;
 	std::list<SpawnStatus> spawns;
 	unsigned int confirm_wait;
+	std::uint16_t player_update_pack;
+	IntervalTimer player_update_timer;
 
 };
 
diff --git a/src/net/Packet.hpp b/src/net/Packet.hpp
index 76cd966..4742a45 100644
--- a/src/net/Packet.hpp
+++ b/src/net/Packet.hpp
@@ -53,6 +53,10 @@ struct Packet {
 		std::size_t length;
 		std::uint8_t *data;
 
+		std::uint16_t Seq() const noexcept {
+			return reinterpret_cast<const Packet *>(data - sizeof(Header))->header.ctrl.seq;
+		}
+
 		template<class T>
 		void Write(const T &, size_t off) noexcept;
 		template<class T>
diff --git a/src/net/net.cpp b/src/net/net.cpp
index e6af690..4e6a63a 100644
--- a/src/net/net.cpp
+++ b/src/net/net.cpp
@@ -51,11 +51,13 @@ IPaddress client_resolve(const char *host, Uint16 port) {
 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{ -1, nullptr, 0 }
+, update_timer(16) {
 	client_pack.data = new Uint8[sizeof(Packet)];
 	client_pack.maxlen = sizeof(Packet);
 	// establish connection
 	SendPing();
+	update_timer.Start();
 }
 
 Client::~Client() {
@@ -91,6 +93,7 @@ void Client::HandlePacket(const UDPpacket &udp_pack) {
 }
 
 void Client::Update(int dt) {
+	update_timer.Update(dt);
 	conn.Update(dt);
 	if (conn.ShouldPing()) {
 		SendPing();
@@ -107,7 +110,9 @@ uint16_t Client::SendLogin(const string &name) {
 	return conn.Send(client_pack, client_sock);
 }
 
-uint16_t Client::SendPlayerUpdate(const Entity &player) {
+int Client::SendPlayerUpdate(const Entity &player) {
+	// don't send all too many updates
+	if (!update_timer.Hit()) return -1;
 	auto pack = Packet::Make<Packet::PlayerUpdate>(client_pack);
 	pack.WritePlayer(player);
 	return conn.Send(client_pack, client_sock);
@@ -124,7 +129,9 @@ ClientConnection::ClientConnection(Server &server, const IPaddress &addr)
 , conn(addr)
 , player(nullptr)
 , spawns()
-, confirm_wait(0) {
+, confirm_wait(0)
+, player_update_pack(0)
+, player_update_timer(1500) {
 	conn.SetHandler(this);
 }
 
@@ -308,6 +315,10 @@ void ClientConnection::On(const Packet::Login &pack) {
 		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;
@@ -323,7 +334,13 @@ void ClientConnection::On(const Packet::Part &) {
 
 void ClientConnection::On(const Packet::PlayerUpdate &pack) {
 	if (!HasPlayer()) return;
-	pack.ReadPlayer(Player());
+	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();
+		pack.ReadPlayer(Player());
+	}
 }
 
 
diff --git a/src/world/World.cpp b/src/world/World.cpp
index 3ff7da3..505cbbb 100644
--- a/src/world/World.cpp
+++ b/src/world/World.cpp
@@ -114,6 +114,26 @@ Entity *World::AddEntity(std::uint32_t id) {
 	return &*entity;
 }
 
+Entity &World::ForceAddEntity(std::uint32_t id) {
+	if (entities.empty() || entities.back().ID() < id) {
+		entities.emplace_back();
+		entities.back().ID(id);
+		return entities.back();
+	}
+
+	auto position = entities.begin();
+	auto end = entities.end();
+	while (position != end && position->ID() < id) {
+		++position;
+	}
+	if (position != end && position->ID() == id) {
+		return *position;
+	}
+	auto entity = entities.emplace(position);
+	entity->ID(id);
+	return *entity;
+}
+
 
 namespace {
 
diff --git a/src/world/World.hpp b/src/world/World.hpp
index 8d82250..cd63161 100644
--- a/src/world/World.hpp
+++ b/src/world/World.hpp
@@ -78,6 +78,9 @@ public:
 	/// add entity with given ID
 	/// returns nullptr if the ID is already taken
 	Entity *AddEntity(std::uint32_t id);
+	/// add entity with given ID
+	/// returs an existing entity if ID is already taken
+	Entity &ForceAddEntity(std::uint32_t id);
 
 	const std::vector<Player> &Players() const noexcept { return players; }
 	std::list<Entity> &Entities() noexcept { return entities; }