use GDREGISTER_CLASS

include/blitz/common/NonCopyable.h

@@ -0,0 +1,25 @@
+#pragma once
+
+/**
+ * \file NonCopyable.h
+ * \brief File containing the blitz::NonCopyable class
+ */
+
+namespace blitz {
+
+/**
+ * \class NonCopyable
+ * \brief Class used to make a class non copyable
+ * \note Inherit from this class privately to make a class non copyable
+ */
+class NonCopyable {
+  public:
+	NonCopyable(const NonCopyable&) = delete;
+	NonCopyable& operator=(const NonCopyable&) = delete;
+
+  protected:
+	NonCopyable() {}
+	~NonCopyable() {}
+};
+
+}  // namespace blitz

include/blitz/common/Types.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <cstdint>
+
+namespace blitz {
+
+using EntityID = std::uint64_t;
+using PeerID = std::int32_t;
+using PlayerID = PeerID;
+
+}  // namespace blitz

include/blitz/protocol/ByteBuffer.h

@@ -0,0 +1,89 @@
+#pragma once
+
+#include <godot_cpp/variant/packed_byte_array.hpp>
+#include <godot_cpp/variant/string.hpp>
+#include <vector>
+
+namespace blitz {
+namespace protocol {
+
+class PlayerInfo;
+
+#define Operators(Type, GodotType)                                                                                                    \
+	ByteBuffer& operator>>(Type& a_Data) {                                                                                            \
+		a_Data = m_Buffer.decode_##GodotType(m_ReadOffset);                                                                           \
+		m_ReadOffset += sizeof(a_Data);                                                                                               \
+		return *this;                                                                                                                 \
+	}                                                                                                                                 \
+                                                                                                                                      \
+	ByteBuffer& operator<<(Type a_Data) {                                                                                             \
+		m_Buffer.resize(m_Buffer.size() + sizeof(a_Data));                                                                            \
+		m_Buffer.encode_##GodotType(m_Buffer.size() - sizeof(a_Data), a_Data);                                                        \
+		return *this;                                                                                                                 \
+	}
+
+class ByteBuffer {
+  private:
+	godot::PackedByteArray m_Buffer;
+	std::size_t m_ReadOffset;
+
+  public:
+	ByteBuffer(godot::PackedByteArray&& a_Buffer) : m_Buffer(std::move(a_Buffer)), m_ReadOffset(0) {}
+	ByteBuffer() : m_ReadOffset(0) {
+		m_Buffer.resize(0);
+	}
+
+	const godot::PackedByteArray& GetByteArray() const {
+		return m_Buffer;
+	}
+
+	godot::PackedByteArray& GetByteArray() {
+		return m_Buffer;
+	}
+
+	// Integers
+	Operators(int8_t, s8);
+	Operators(uint8_t, u8);
+	Operators(int16_t, s16);
+	Operators(uint16_t, u16);
+	Operators(int32_t, s32);
+	Operators(uint32_t, u32);
+	Operators(int64_t, s64);
+	Operators(uint64_t, u64);
+
+	// Reals
+	Operators(float, float);
+	Operators(double, double);
+
+	ByteBuffer& operator<<(const godot::String& a_Data);
+	ByteBuffer& operator>>(godot::String& a_Data);
+
+	ByteBuffer& operator<<(const godot::Vector3& a_Data);
+	ByteBuffer& operator>>(godot::Vector3& a_Data);
+
+	template <typename T>
+	ByteBuffer& operator<<(const std::vector<T>& a_Data) {
+		*this << static_cast<std::uint32_t>(a_Data.size());
+		for (const T& data : a_Data) {
+			*this << data;
+		}
+		return *this;
+	}
+
+	template <typename T>
+	ByteBuffer& operator>>(std::vector<T>& a_Data) {
+		std::uint32_t arraySize;
+		*this >> arraySize;
+		a_Data.resize(arraySize);
+		for (std::uint32_t i = 0; i < arraySize; i++) {
+			*this >> a_Data[i];
+		}
+		return *this;
+	}
+
+	ByteBuffer& operator<<(const PlayerInfo& a_Data);
+	ByteBuffer& operator>>(PlayerInfo& a_Data);
+};
+
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketData.h

@@ -0,0 +1,72 @@
+#pragma once
+
+#include <blitz/common/Types.h>
+#include <vector>
+#include <godot_cpp/variant/string.hpp>
+#include <godot_cpp/variant/vector3.hpp>
+
+namespace blitz {
+namespace protocol {
+
+struct PlayerInfo {
+	PlayerID m_PlayerId;
+	godot::String m_PlayerName;
+};
+
+namespace data {
+
+struct PlayerLogin {
+	godot::String m_PlayerName;
+};
+
+struct UpdateHealth {
+	float m_NewHealth;
+};
+
+struct LoggingSuccess {
+	PlayerID m_PlayerId;
+};
+
+struct PlayerDeath {};
+
+struct PlayerJoin {
+	PlayerInfo m_Player;
+};
+
+struct PlayerLeave {
+	PlayerID m_PlayerId;
+};
+
+struct PlayerStats {};
+
+struct PlayerList {
+	std::vector<PlayerInfo> m_Players;
+};
+
+struct ServerConfig {};
+
+struct ServerTps {};
+
+struct UpdateGameState {};
+
+struct KeepAlive {
+	std::uint64_t m_KeepAliveId;
+};
+
+struct Disconnect {};
+
+struct ChatMessage {
+	godot::String m_Text;
+};
+
+struct PlayerPositionAndRotation {
+	PlayerID m_Player;
+	godot::Vector3 m_Position;
+	godot::Vector3 m_Rotation;
+};
+
+struct PlayerShoot {};
+
+}  // namespace data
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketDeclare.h

@@ -0,0 +1,49 @@
+#pragma once
+
+/**
+ * \file PacketDeclare.h
+ * \brief Holds the definitions of the packets (but not their content)
+ */
+
+namespace blitz {
+namespace protocol {
+
+/**
+ * \enum PacketSender
+ * \brief Indicate who should send a packet
+ */
+enum class PacketSender {
+	/** Sent by clients and server */
+	Both,
+	/** Sent by clients to the server */
+	Client,
+	/** Sent by server to the clients */
+	Server,
+};
+
+
+/**
+ * \def DeclareAllPacket
+ * \brief Avoids repetitive operations on packets
+ */
+#define DeclareAllPacket() \
+	DeclarePacket(ChatMessage, Reliable, Both) \
+	DeclarePacket(Disconnect, Reliable, Both) \
+	DeclarePacket(KeepAlive, Reliable, Both)  \
+	DeclarePacket(LoggingSuccess, Reliable, Server) \
+	DeclarePacket(PlayerDeath, Reliable, Server) \
+	DeclarePacket(PlayerJoin, Reliable, Server) \
+	DeclarePacket(PlayerLeave, Reliable, Server) \
+	DeclarePacket(PlayerList, Reliable, Server) \
+	DeclarePacket(PlayerLogin, Reliable, Client) \
+	DeclarePacket(PlayerPositionAndRotation, Reliable, Both) \
+	DeclarePacket(PlayerShoot, Reliable, Both) \
+	DeclarePacket(PlayerStats, Reliable, Server) \
+	DeclarePacket(ServerConfig, Reliable, Server) \
+	DeclarePacket(ServerTps, Reliable, Server) \
+	DeclarePacket(UpdateGameState, Reliable, Server) \
+	DeclarePacket(UpdateHealth, Reliable, Client)
+
+
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketDispatcher.h

@@ -0,0 +1,58 @@
+#pragma once
+
+/**
+ * \file PacketDispatcher.h
+ * \brief File containing the blitz::protocol::PacketDispatcher class
+ */
+
+#include <blitz/common/NonCopyable.h>
+#include <blitz/protocol/Packets.h>
+
+#include <map>
+
+namespace blitz {
+namespace protocol {
+
+class PacketHandler;
+
+/**
+ * \class PacketDispatcher
+ * \brief Class used to dispatch packets
+ */
+class PacketDispatcher : private NonCopyable {
+  private:
+	std::map<PacketType, std::vector<PacketHandler*>> m_Handlers;
+
+  public:
+	/**
+	 * \brief Constructor
+	 */
+	PacketDispatcher() {}
+
+	/**
+	 * \brief Dispatch a packet
+	 * \param packet The packet to dispatch
+	 */
+	void Dispatch(const Packet& packet);
+
+	/**
+	 * \brief Register a packet handler
+	 * \param type The packet type
+	 * \param handler The packet handler
+	 */
+	void RegisterHandler(PacketType type, PacketHandler& handler);
+	/**
+	 * \brief Unregister a packet handler
+	 * \param type The packet type
+	 * \param handler The packet handler
+	 */
+	void UnregisterHandler(PacketType type, PacketHandler& handler);
+	/**
+	 * \brief Unregister a packet handler
+	 * \param handler The packet handler
+	 */
+	void UnregisterHandler(PacketHandler& handler);
+};
+
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketFactory.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <blitz/protocol/Packets.h>
+#include <memory>
+
+namespace blitz {
+namespace protocol {
+namespace PacketFactory {
+
+template<typename PacketDerived, typename = typename std::enable_if<std::is_base_of<Packet, PacketDerived>::value>::type>
+std::unique_ptr<PacketDerived> CreatePacket() {
+    return std::make_unique<PacketDerived>();
+}
+
+const std::unique_ptr<Packet>& CreateReadOnlyPacket(PacketType a_Type);
+
+void Init();
+
+}  // namespace PacketFactory
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketHandler.h

@@ -0,0 +1,34 @@
+#pragma once
+
+/**
+ * \file PacketHandler.h
+ * \brief File containing the blitz::protocol::PacketHandler class
+ */
+
+#include <blitz/protocol/Packets.h>
+#include <blitz/protocol/PacketVisitor.h>
+
+namespace blitz {
+namespace protocol {
+
+class PacketDispatcher;
+
+#define DeclarePacket(PacketName, ...) virtual void Visit(const packets::PacketName&); virtual void HandlePacket(const packets::PacketName&) {}
+
+/**
+ * \class PacketHandler
+ * \brief Class used to handle packets
+ */
+class PacketHandler : public PacketVisitor {
+  public:
+	PacketHandler() {}
+	~PacketHandler() {}
+
+	DeclareAllPacket()
+
+};
+
+#undef DeclarePacket
+
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketSerializer.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <blitz/protocol/Packets.h>
+#include <godot_cpp/variant/packed_byte_array.hpp>
+#include <memory>
+
+namespace blitz {
+namespace protocol {
+
+using PacketPtr = std::unique_ptr<Packet>;
+
+namespace PacketSerializer {
+
+godot::PackedByteArray Serialize(const Packet& a_Packet);
+
+std::unique_ptr<Packet> Deserialize(godot::PackedByteArray& a_Data);
+
+}
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/PacketVisitor.h

@@ -0,0 +1,39 @@
+#pragma once
+
+/**
+ * \file PacketVisitor.h
+ * \brief File containing the blitz::protocol::PacketVisitor class
+ */
+
+#include <blitz/protocol/Packets.h>
+
+namespace blitz {
+namespace protocol {
+
+#define DeclarePacket(PacketName, ...)                                                                                                \
+	/** This function is called when the packet processed by PacketVisitor::Check is a PacketName */                                                                                                                            \
+	virtual void Visit(const packets::PacketName&) {}
+
+/**
+ * \class PacketVisitor
+ * \brief This class uses double-dispatch in order to find the real type of a packet
+ */
+class PacketVisitor : private NonCopyable {
+  protected:
+	PacketVisitor() {}
+	virtual ~PacketVisitor() {}
+
+  public:
+	/**
+	 * \brief Calls the right PacketVisitor::Visit method corresponding to the real type of the packet
+	 * \param packet the Packet to visit
+	 */
+	void Check(const Packet& packet);
+
+	DeclareAllPacket()
+};
+
+#undef DeclarePacket
+
+}  // namespace protocol
+}  // namespace blitz

include/blitz/protocol/Packets.h

@@ -0,0 +1,112 @@
+#pragma once
+
+/**
+ * \file Packets.h
+ * \brief File containing the definitions of the packets
+ */
+
+#include <blitz/common/NonCopyable.h>
+#include <blitz/protocol/PacketData.h>
+#include <blitz/protocol/PacketDeclare.h>
+
+namespace blitz {
+namespace protocol {
+
+class PacketVisitor;
+
+/** A Packet id is 8 bits wide */
+using PacketID = std::uint8_t;
+
+#define DeclarePacket(PacketName, ...) /** PacketName */ PacketName,
+
+/**
+ * \enum PacketType
+ * \brief Map a Packet to an id
+ */
+enum class PacketType : PacketID {
+
+	DeclareAllPacket()
+
+	/** The number of packets */
+	PACKET_COUNT
+};
+
+
+#undef DeclarePacket
+
+
+class Packet : private NonCopyable {
+  public:
+	/**
+	 * \return The real type of the packet
+	 */
+	virtual PacketType GetType() const = 0;
+
+	/**
+	 * \brief The network peer who sent the packet
+	 */
+	PeerID m_Sender;
+
+  private:
+	/** Use a PacketVisitor to make double-dispatch possible */
+	virtual void Accept(PacketVisitor& a_Visitor) const = 0;
+
+	friend class PacketVisitor;
+};
+
+
+
+
+
+namespace packets {
+
+/**
+ * \class ConcretePacket
+ * \brief A Packet associated with an id and holding data
+ * \tparam PT The packet type
+ * \tparam Data The structure holding the data of the packet (in blitz::protocol::data namespace)
+ */
+template <PacketType PT, typename Data>
+class ConcretePacket : public Packet {
+  public:
+	/** The type of the struct holding the data */
+	using PacketDataType = Data;
+
+	/** The structure holding the actual data */
+	PacketDataType m_Data;
+
+	/** Construct the packet with data of type PacketDataType */
+	ConcretePacket(const PacketDataType& a_Data = {});
+
+	constexpr PacketType GetType() const override {
+		return PT;
+	};
+
+  private:
+	void Accept(PacketVisitor& a_Visitor) const override;
+};
+
+
+
+
+
+// define BLITZ_INSTANCIATE_PACKETS
+// before including this file
+// if you want to instantiate templates
+#ifdef BLITZ_INSTANCIATE_PACKETS
+#define DeclarePacket(PacketName, ...)                                                                                                \
+	using PacketName = ConcretePacket<PacketType::PacketName, data::PacketName>;                                                      \
+	template class ConcretePacket<PacketType::PacketName, data::PacketName>;
+#else
+#define DeclarePacket(PacketName, ...) /** Defines the PacketName packet */                                                           \
+	using PacketName = ConcretePacket<PacketType::PacketName, data::PacketName>;
+#endif
+
+DeclareAllPacket()
+
+#undef DeclarePacket
+
+}  // namespace packets
+
+}  // namespace protocol
+}  // namespace blitz

src/Lobby.cpp

@@ -70,13 +70,13 @@ void Lobby::Shutdown() {
 	}
 }
 
-void Lobby::OnPlayerConnected(int64_t a_PeerId) {
+void Lobby::OnPlayerConnected(PeerID a_PeerId) {
 	if (get_multiplayer()->is_server()) {
 		emit_signal("player_connected", a_PeerId);
 	}
 }
 
-void Lobby::OnPlayerDisconnected(int64_t a_PeerId) {
+void Lobby::OnPlayerDisconnected(PeerID a_PeerId) {
 	if (get_multiplayer()->is_server()) {
 		emit_signal("player_disconnected", a_PeerId);
 	}

src/Lobby.h

@@ -22,8 +22,8 @@ class Lobby : public godot::Node {
 	void Shutdown();
 
   private:
-	void OnPlayerConnected(int64_t a_PeerId);
+	void OnPlayerConnected(PeerID a_PeerId);
-	void OnPlayerDisconnected(int64_t a_PeerId);
+	void OnPlayerDisconnected(PeerID a_PeerId);
 	void OnConnectOk();
 	void OnConnectFail();
 	void OnServerDisconnected();

src/NetworkInterface.cpp

@@ -1,5 +1,7 @@
 #include "NetworkInterface.h"
 
+#include <blitz/protocol/PacketFactory.h>
+#include <blitz/protocol/PacketSerializer.h>
 #include <godot_cpp/classes/multiplayer_api.hpp>
 #include <godot_cpp/classes/multiplayer_peer.hpp>
 #include <godot_cpp/variant/utility_functions.hpp>
@@ -9,49 +11,40 @@ namespace blitz {
 using namespace godot;
 
 void NetworkInterface::_bind_methods() {
-	ClassDB::bind_method(D_METHOD("AddPlayer", "a_PlayerId", "a_PlayerName"), &NetworkInterface::AddPlayer);
+	ClassDB::bind_method(D_METHOD("RecievePacketDataReliable", "a_PacketData"), &NetworkInterface::RecievePacketDataReliable);
-	ClassDB::bind_method(D_METHOD("RemovePlayer", "a_PlayerId"), &NetworkInterface::RemovePlayer);
+	protocol::PacketFactory::Init();
-	ClassDB::bind_method(D_METHOD("SetPlayerPositionAndRotation", "a_PlayerId", "a_Position", "a_Rotation"),
-		&NetworkInterface::SetPlayerPositionAndRotation);
-
-	ADD_SIGNAL(MethodInfo("AddPlayer", PropertyInfo(Variant::INT, "a_PlayerId"), PropertyInfo(Variant::STRING, "a_PlayerName")));
-	ADD_SIGNAL(MethodInfo("RemovePlayer", PropertyInfo(Variant::INT, "a_PlayerId")));
-	ADD_SIGNAL(MethodInfo("SetPlayerPositionAndRotation", PropertyInfo(Variant::INT, "a_PlayerId"),
-		PropertyInfo(Variant::VECTOR3, "a_Position"), PropertyInfo(Variant::VECTOR3, "a_Rotation")));
 }
 
 NetworkInterface::NetworkInterface() {}
 
 NetworkInterface::~NetworkInterface() {}
 
-void NetworkInterface::AddPlayer(int64_t a_PlayerId, godot::String a_PlayerName) {
-	emit_signal("AddPlayer", a_PlayerId, a_PlayerName);
-}
-
-void NetworkInterface::RemovePlayer(int64_t a_PlayerId) {
-	emit_signal("RemovePlayer", a_PlayerId);
-}
-
-void NetworkInterface::SetPlayerPositionAndRotation(int64_t a_PlayerId, Vector3 a_Position, Vector3 a_Rotation) {
-	emit_signal("SetPlayerPositionAndRotation", a_PlayerId, a_Position, a_Rotation);
-}
-
 void NetworkInterface::_ready() {
+	// TODO: unreliable
 	Dictionary config;
-	config["rpc_mode"] = MultiplayerAPI::RPC_MODE_AUTHORITY;
+	config["rpc_mode"] = MultiplayerAPI::RPC_MODE_ANY_PEER;
 	config["transfer_mode"] = MultiplayerPeer::TRANSFER_MODE_RELIABLE;
 	config["call_local"] = true;
 	config["channel"] = 0;
-	rpc_config("AddPlayer", config);
+	rpc_config("RecievePacketDataReliable", config);
-	rpc_config("RemovePlayer", config);
-
-	Dictionary config2;
-	config["transfer_mode"] = MultiplayerPeer::TRANSFER_MODE_RELIABLE;
-	config["channel"] = 0;
-	config2["rpc_mode"] = MultiplayerAPI::RPC_MODE_ANY_PEER;
-	config2["call_local"] = false;
-	rpc_config("SetPlayerPositionAndRotation", config2);
 }
 
+void NetworkInterface::BroadcastPacket(const protocol::Packet& a_Packet) {
+	PackedByteArray byteArray = protocol::PacketSerializer::Serialize(a_Packet);
+	rpc("RecievePacketDataReliable", byteArray);
+}
+
+void NetworkInterface::SendPacket(PeerID a_Peer, const protocol::Packet& a_Packet) {
+	PackedByteArray byteArray = protocol::PacketSerializer::Serialize(a_Packet);
+	rpc_id(a_Peer, "RecievePacketDataReliable", byteArray);
+}
+
+void NetworkInterface::RecievePacketDataReliable(godot::PackedByteArray a_PacketData) {
+	auto packet = protocol::PacketSerializer::Deserialize(a_PacketData);
+	if (packet) {
+		packet->m_Sender = get_multiplayer()->get_remote_sender_id();
+		Dispatch(*packet);
+	}
+}
 
 }  // namespace blitz

src/NetworkInterface.h

@@ -1,9 +1,11 @@
 #pragma once
 
+#include <blitz/protocol/Packets.h>
 #include <godot_cpp/classes/node.hpp>
+#include <blitz/protocol/PacketDispatcher.h>
 
 namespace blitz {
-class NetworkInterface : public godot::Node {
+class NetworkInterface : public godot::Node, public protocol::PacketDispatcher {
 	GDCLASS(NetworkInterface, godot::Node)
   protected:
 	static void _bind_methods();
@@ -12,11 +14,13 @@ class NetworkInterface : public godot::Node {
 	NetworkInterface();
 	~NetworkInterface();
 
-    void AddPlayer(int64_t a_PlayerId, godot::String a_PlayerName);
+	void BroadcastPacket(const protocol::Packet& a_Packet);
-	void RemovePlayer(int64_t a_PlayerId);
+	void SendPacket(PeerID a_Peer, const protocol::Packet& a_Packet);
-	void SetPlayerPositionAndRotation(int64_t a_PlayerId, godot::Vector3 a_Position, godot::Vector3 a_Rotation);
 
-    void _ready() override;
+	void _ready() override;
+  
+  private:
+	void RecievePacketDataReliable(godot::PackedByteArray a_PacketData);
 };
 
 }  // namespace blitz

src/Player.h

@@ -3,6 +3,7 @@
 #include <godot_cpp/classes/animation_tree.hpp>
 #include <godot_cpp/classes/character_body3d.hpp>
 #include <godot_cpp/classes/node3d.hpp>
+#include <blitz/common/Types.h>
 
 namespace blitz {
 
@@ -26,7 +27,7 @@ class Player : public godot::CharacterBody3D {
 	godot::Vector3 GetCameraRotation() const;
 	void SetCameraRotation(const godot::Vector3& a_Rotation);
 
-	uint64_t GetId() const {
+	PlayerID GetId() const {
 		return m_PeerId;
 	}
 
@@ -36,7 +37,7 @@ class Player : public godot::CharacterBody3D {
 
 	godot::Vector3 m_SnapVector;
 	float m_Speed;
-	uint64_t m_PeerId;
+	PeerID m_PeerId;
 
 	friend class World;
 };

src/Server.cpp

@@ -28,17 +28,18 @@ void Server::_ready() {
 	m_Lobby->connect("player_disconnected", callable_mp(this, &Server::OnPlayerDisconnect));
 }
 
-void Server::OnPlayerConnect(uint64_t a_PeerId) {
+void Server::OnPlayerConnect(PeerID a_PeerId) {
+	protocol::PlayerInfo playerInfo{a_PeerId, "whoami"};
 	for (int i = 0; i < m_Peers.size(); i++) {
-		m_NetworkInterface->rpc_id(a_PeerId, "AddPlayer", m_Peers[i], "Aucuneidee");
+		m_NetworkInterface->SendPacket(a_PeerId, protocol::packets::PlayerJoin({m_Peers[i], "whoami"}));
 	}
 	m_Peers.push_back(a_PeerId);
-	m_NetworkInterface->rpc("AddPlayer", a_PeerId, "Aucuneidee");
+	m_NetworkInterface->BroadcastPacket(protocol::packets::PlayerJoin({playerInfo}));
 }
 
-void Server::OnPlayerDisconnect(uint64_t a_PeerId) {
+void Server::OnPlayerDisconnect(PeerID a_PeerId) {
 	m_Peers.erase(a_PeerId);
-	m_NetworkInterface->rpc("RemovePlayer", a_PeerId);
+	m_NetworkInterface->BroadcastPacket(protocol::packets::PlayerLeave({a_PeerId}));
 }
 
 }  // namespace blitz

src/Server.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <godot_cpp/classes/node.hpp>
+#include <blitz/common/Types.h>
 
 namespace blitz {
 
@@ -18,14 +19,14 @@ class Server : public godot::Node {
 
 	void _ready() override;
 
-    void OnPlayerConnect(uint64_t a_PeerId);
+    void OnPlayerConnect(PeerID a_PeerId);
-    void OnPlayerDisconnect(uint64_t a_PeerId);
+    void OnPlayerDisconnect(PeerID a_PeerId);
 
   private:
     Lobby* m_Lobby;
     NetworkInterface* m_NetworkInterface;
 
-    godot::TypedArray<uint64_t> m_Peers;
+    godot::TypedArray<PeerID> m_Peers;
 };
 
 }  // namespace blitz

src/World.cpp

@@ -32,37 +32,53 @@ void World::_ready() {
 	m_NetworkInterface = Object::cast_to<NetworkInterface>(lobby->find_child("NetworkInterface"));
 	DEV_ASSERT(m_NetworkInterface);
 
-	m_NetworkInterface->connect("AddPlayer", callable_mp(this, &World::AddPlayer));
+	m_NetworkInterface->RegisterHandler(protocol::PacketType::PlayerJoin, *this);
-	m_NetworkInterface->connect("RemovePlayer", callable_mp(this, &World::RemovePlayer));
+	m_NetworkInterface->RegisterHandler(protocol::PacketType::PlayerLeave, *this);
-	m_NetworkInterface->connect("SetPlayerPositionAndRotation", callable_mp(this, &World::SetPlayerPositionAndRotation));
+	m_NetworkInterface->RegisterHandler(protocol::PacketType::PlayerPositionAndRotation, *this);
 }
 
 
 World::World() {}
 
-World::~World() {}
+World::~World() {
+	if (Engine::get_singleton()->is_editor_hint())
+		return;
+
+	m_NetworkInterface->UnregisterHandler(*this);
+}
 
 void World::_process(float delta) {
 #if DEBUG_ENABLED
 	if (Engine::get_singleton()->is_editor_hint())
 		return;
 #endif
+	m_PassedTime += delta;
+	if (m_PassedTime < 0.05f)
+		return;
+
+	// UtilityFunctions::print(m_PassedTime);
+
+	// m_PassedTime -= 0.05f;
+	// if (m_PassedTime > 0.5f)
+	// 	m_PassedTime = 0.0f;
+
 	if (get_multiplayer()->is_server()) {
 		for (int i = 0; i < m_Players->get_child_count(); i++) {
 			Player* player = Object::cast_to<Player>(m_Players->get_child(i));
 			DEV_ASSERT(player);
-			m_NetworkInterface->rpc(
+			m_NetworkInterface->BroadcastPacket(
-				"SetPlayerPositionAndRotation", player->m_PeerId, player->get_position(), player->GetCameraRotation());
+				protocol::packets::PlayerPositionAndRotation({player->GetId(), player->get_position(), player->GetCameraRotation()}));
 		}
 	} else {
 		Player* player = GetPlayerById(get_multiplayer()->get_unique_id());
-		if (player)
+		if (player) {
-			m_NetworkInterface->rpc("SetPlayerPositionAndRotation", get_multiplayer()->get_unique_id(), player->get_position(),
+			m_NetworkInterface->BroadcastPacket(protocol::packets::PlayerPositionAndRotation(
-				player->GetCameraRotation());
+				{get_multiplayer()->get_unique_id(), player->get_position(), player->GetCameraRotation()}));
+		}
 	}
 }
 
-Player* World::GetPlayerById(uint64_t a_PlayerId) {
+Player* World::GetPlayerById(PlayerID a_PlayerId) {
 	String stringId = UtilityFunctions::var_to_str(a_PlayerId);
 	for (int i = 0; i < m_Players->get_child_count(); i++) {
 		Node* player = m_Players->get_child(i);
@@ -73,8 +89,25 @@ Player* World::GetPlayerById(uint64_t a_PlayerId) {
 	return nullptr;
 }
 
-void World::AddPlayer(int32_t a_PlayerId, String a_PlayerName) {
+void World::HandlePacket(const protocol::packets::PlayerJoin& a_PlayerJoin) {
-	UtilityFunctions::print("New Player with id : ", a_PlayerId);
+	const protocol::PlayerInfo& playerInfo = a_PlayerJoin.m_Data.m_Player;
+	AddPlayer(playerInfo.m_PlayerId, playerInfo.m_PlayerName);
+}
+
+void World::HandlePacket(const protocol::packets::PlayerLeave& a_PlayerLeave) {
+	RemovePlayer(a_PlayerLeave.m_Data.m_PlayerId);
+}
+
+void World::HandlePacket(const protocol::packets::PlayerPositionAndRotation& a_PlayerPos) {
+	const auto& data = a_PlayerPos.m_Data;
+	if (data.m_Player == get_multiplayer()->get_unique_id() || data.m_Player != a_PlayerPos.m_Sender)
+		return;
+
+	SetPlayerPositionAndRotation(data.m_Player, data.m_Position, data.m_Rotation);
+}
+
+void World::AddPlayer(PlayerID a_PlayerId, String a_PlayerName) {
+	UtilityFunctions::print("New Player with id : ", a_PlayerId, " and name ", a_PlayerName);
 	if (a_PlayerId == get_multiplayer()->get_unique_id()) {
 		Ref<PackedScene> serverScene = ResourceLoader::get_singleton()->load(FirstPersonPlayerScenePath);
 		FirstPersonPlayer* player = Object::cast_to<FirstPersonPlayer>(serverScene->instantiate());
@@ -90,7 +123,7 @@ void World::AddPlayer(int32_t a_PlayerId, String a_PlayerName) {
 	}
 }
 
-void World::RemovePlayer(int32_t a_PlayerId) {
+void World::RemovePlayer(PlayerID a_PlayerId) {
 	UtilityFunctions::print("Removing Player with id : ", a_PlayerId);
 	Player* player = GetPlayerById(a_PlayerId);
 	if (player) {
@@ -98,10 +131,7 @@ void World::RemovePlayer(int32_t a_PlayerId) {
 	}
 }
 
-void World::SetPlayerPositionAndRotation(int64_t a_PlayerId, Vector3 a_Position, Vector3 a_Rotation) {
+void World::SetPlayerPositionAndRotation(PlayerID a_PlayerId, const Vector3& a_Position, const Vector3& a_Rotation) {
-	if (a_PlayerId == get_multiplayer()->get_unique_id())
-		return;
-
 	Player* player = GetPlayerById(a_PlayerId);
 	if (player) {
 		player->set_position(a_Position);

src/World.h

@@ -2,12 +2,14 @@
 
 #include <godot_cpp/classes/node3d.hpp>
 
+#include <blitz/protocol/PacketHandler.h>
+
 namespace blitz {
 
 class Player;
 class NetworkInterface;
 
-class World : public godot::Node3D {
+class World : public godot::Node3D, public protocol::PacketHandler {
 	GDCLASS(World, godot::Node3D)
   protected:
 	static void _bind_methods();
@@ -16,19 +18,24 @@ class World : public godot::Node3D {
 	World();
 	~World();
 
+	// Godot overrides
+	void _ready() override;
 	void _process(float delta);
 
-	void _ready() override;
+	Player* GetPlayerById(PlayerID a_PlayerId);
 
-	Player* GetPlayerById(uint64_t a_PlayerId);
+	void HandlePacket(const protocol::packets::PlayerJoin&) override;
-
+	void HandlePacket(const protocol::packets::PlayerLeave&) override;
-	void AddPlayer(int32_t a_PlayerId, godot::String a_PlayerName);
+	void HandlePacket(const protocol::packets::PlayerPositionAndRotation&) override;
-	void RemovePlayer(int32_t a_PlayerId);
-	void SetPlayerPositionAndRotation(int64_t a_PlayerId, godot::Vector3 a_Position, godot::Vector3 a_Rotation);
 
   private:
 	NetworkInterface* m_NetworkInterface;
 	godot::Node* m_Players;
 	float m_PassedTime;
+
+
+	void AddPlayer(PlayerID a_PlayerId, godot::String a_PlayerName);
+	void RemovePlayer(PlayerID a_PlayerId);
+	void SetPlayerPositionAndRotation(PlayerID a_PlayerId, const godot::Vector3& a_Position, const godot::Vector3& a_Rotation);
 };
 }  // namespace blitz

src/blitz/protocol/ByteBuffer.cpp

@@ -0,0 +1,49 @@
+#include <blitz/protocol/ByteBuffer.h>
+
+#include <blitz/protocol/PacketData.h>
+
+namespace blitz {
+namespace protocol {
+
+ByteBuffer& ByteBuffer::operator>>(PlayerInfo& a_Data) {
+	*this >> a_Data.m_PlayerId >> a_Data.m_PlayerName;
+	return *this;
+}
+
+ByteBuffer& ByteBuffer::operator<<(const PlayerInfo& a_Data) {
+	*this << a_Data.m_PlayerId << a_Data.m_PlayerName;
+	return *this;
+}
+
+ByteBuffer& ByteBuffer::operator<<(const godot::Vector3& a_Data) {
+	*this << a_Data.x << a_Data.y << a_Data.z;
+	return *this;
+}
+
+ByteBuffer& ByteBuffer::operator>>(godot::Vector3& a_Data) {
+	*this >> a_Data.x >> a_Data.y >> a_Data.z;
+	return *this;
+}
+
+ByteBuffer& ByteBuffer::operator>>(godot::String& a_Data) {
+	int nullPos = m_Buffer.find(0, m_ReadOffset);
+	// TODO: error handling
+	if (nullPos < 0)
+		return *this;
+
+	godot::PackedByteArray stringBuffer = m_Buffer.slice(m_ReadOffset, nullPos);
+	a_Data = stringBuffer.get_string_from_utf8();
+	m_ReadOffset = nullPos + 1;
+	return *this;
+}
+
+ByteBuffer& ByteBuffer::operator<<(const godot::String& a_Data) {
+	godot::PackedByteArray stringBuffer = a_Data.to_utf8_buffer();
+	m_Buffer.append_array(stringBuffer);
+	// ends the string
+	*this << static_cast<std::uint8_t>(0);
+	return *this;
+}
+
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/PacketDispatcher.cpp

@@ -0,0 +1,37 @@
+#include <blitz/protocol/PacketDispatcher.h>
+
+#include <algorithm>
+#include <blitz/protocol/PacketHandler.h>
+
+namespace blitz {
+namespace protocol {
+
+void PacketDispatcher::RegisterHandler(PacketType type, PacketHandler& handler) {
+	auto found = std::find(m_Handlers[type].begin(), m_Handlers[type].end(), &handler);
+	if (found == m_Handlers[type].end())
+		m_Handlers[type].push_back(&handler);
+}
+
+void PacketDispatcher::UnregisterHandler(PacketType type, PacketHandler& handler) {
+	m_Handlers[type].erase(std::remove(m_Handlers[type].begin(), m_Handlers[type].end(), &handler), m_Handlers[type].end());
+}
+
+void PacketDispatcher::UnregisterHandler(PacketHandler& handler) {
+	for (auto& pair : m_Handlers) {
+		if (pair.second.empty())
+			continue;
+
+		PacketType type = pair.first;
+
+		m_Handlers[type].erase(std::remove(m_Handlers[type].begin(), m_Handlers[type].end(), &handler), m_Handlers[type].end());
+	}
+}
+
+void PacketDispatcher::Dispatch(const Packet& packet) {
+	PacketType type = packet.GetType();
+	for (PacketHandler* handler : m_Handlers[type])
+		handler->Check(packet);
+}
+
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/PacketFactory.cpp

@@ -0,0 +1,32 @@
+#include <blitz/protocol/PacketFactory.h>
+
+#include <array>
+#include <cassert>
+#include <functional>
+
+namespace blitz {
+namespace protocol {
+namespace PacketFactory {
+
+using PacketCreator = std::function<std::unique_ptr<Packet>()>;
+
+#define DeclarePacket(PacketName, ...) std::make_unique<packets::PacketName>(),
+
+static std::array<std::unique_ptr<Packet>, static_cast<std::size_t>(PacketType::PACKET_COUNT)> Packets;
+
+void Init() {
+	Packets = {
+
+		DeclareAllPacket()
+
+	};
+}
+
+const std::unique_ptr<Packet>& CreateReadOnlyPacket(PacketType a_Type) {
+	assert(a_Type < PacketType::PACKET_COUNT);
+	return Packets[static_cast<std::size_t>(a_Type)];
+}
+
+}  // namespace PacketFactory
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/PacketHandler.cpp

@@ -0,0 +1,14 @@
+#include <blitz/protocol/PacketHandler.h>
+
+namespace blitz {
+namespace protocol {
+
+#define DeclarePacket(PacketName, ...)                                                                                                \
+	void PacketHandler::Visit(const packets::PacketName& a_Packet) {                                                                  \
+		HandlePacket(a_Packet);                                                                                                       \
+	}
+
+DeclareAllPacket()
+
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/PacketSerializer.cpp

@@ -0,0 +1,294 @@
+#include <blitz/protocol/PacketSerializer.h>
+
+#include <blitz/protocol/ByteBuffer.h>
+#include <blitz/protocol/PacketFactory.h>
+#include <blitz/protocol/PacketVisitor.h>
+
+#include <godot_cpp/variant/utility_functions.hpp>
+#include <godot_cpp/variant/variant.hpp>
+
+namespace blitz {
+namespace protocol {
+namespace PacketSerializer {
+
+#define DeclarePacket(PacketName, ...)                                                                                                \
+	void Visit(const packets::PacketName& a_Packet) override {                                                                        \
+		const auto& packetData = a_Packet.m_Data;                                                                                     \
+		SerializePacketData(packetData);                                                                                              \
+	}                                                                                                                                 \
+                                                                                                                                      \
+	void SerializePacketData(const packets::PacketName::PacketDataType& a_Packet);
+
+
+
+
+class Serializer : public PacketVisitor {
+  private:
+	ByteBuffer& m_Buffer;
+
+  public:
+	Serializer(ByteBuffer& a_Buffer) : m_Buffer(a_Buffer) {}
+
+	void Serialize(const Packet& a_Packet) {
+		m_Buffer << static_cast<PacketID>(a_Packet.GetType());
+		Check(a_Packet);
+	}
+
+	DeclareAllPacket()
+};
+
+#undef DeclarePacket
+
+
+
+
+
+#define DeclarePacket(PacketName, ...)                                                                                                \
+	void Visit(const packets::PacketName& a_Packet) override {                                                                        \
+		auto packetPtr = PacketFactory::CreatePacket<packets::PacketName>();                                                          \
+		auto& packetData = packetPtr->m_Data;                                                                                         \
+                                                                                                                                      \
+		DeserializePacketData(packetData);                                                                                            \
+                                                                                                                                      \
+		m_Packet = std::move(packetPtr);                                                                                              \
+	}                                                                                                                                 \
+                                                                                                                                      \
+	void DeserializePacketData(packets::PacketName::PacketDataType& a_Packet);
+
+
+
+class Deserializer : public PacketVisitor {
+  private:
+	ByteBuffer& m_Buffer;
+	PacketPtr m_Packet;
+
+  public:
+	Deserializer(ByteBuffer&& a_Buffer) : m_Buffer(a_Buffer) {}
+
+	bool Deserialize(const PacketPtr& a_Packet) {
+		try {
+			Check(*a_Packet.get());
+		} catch (std::exception& e) {
+			return false;
+		}
+		return true;
+	}
+
+	PacketPtr& GetPacket() {
+		return m_Packet;
+	}
+
+	DeclareAllPacket()
+};
+
+
+
+
+
+godot::PackedByteArray Serialize(const Packet& a_Packet) {
+	ByteBuffer stream;
+
+	Serializer serializer(stream);
+	serializer.Serialize(a_Packet);
+
+	return stream.GetByteArray();
+}
+
+std::unique_ptr<Packet> Deserialize(godot::PackedByteArray& a_Data) {
+	ByteBuffer stream(std::move(a_Data));
+
+	PacketID packetId;
+	stream >> packetId;
+
+	if (packetId >= static_cast<PacketID>(PacketType::PACKET_COUNT))
+		return nullptr;
+
+	PacketType packetType = PacketType(packetId);
+
+	// for double-dispatch
+	const PacketPtr& emptyPacket = PacketFactory::CreateReadOnlyPacket(packetType);
+
+	Deserializer deserializer(std::move(stream));
+	if (deserializer.Deserialize(emptyPacket)) {
+		PacketPtr packet = std::move(deserializer.GetPacket());
+		return packet;
+	}
+
+	return nullptr;
+}
+
+
+
+
+
+//---------------------------------------------
+// Packet serializer implementation
+//----------------------------------------------
+
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerLogin& a_Packet) {
+	m_Buffer << a_Packet.m_PlayerName;
+}
+
+void Deserializer::DeserializePacketData(data::PlayerLogin& a_Packet) {
+	m_Buffer >> a_Packet.m_PlayerName;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::UpdateHealth& a_Packet) {
+	m_Buffer << a_Packet.m_NewHealth;
+}
+
+void Deserializer::DeserializePacketData(data::UpdateHealth& a_Packet) {
+	m_Buffer >> a_Packet.m_NewHealth;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::LoggingSuccess& a_Packet) {
+	m_Buffer << a_Packet.m_PlayerId;
+}
+
+void Deserializer::DeserializePacketData(data::LoggingSuccess& a_Packet) {
+	m_Buffer >> a_Packet.m_PlayerId;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerDeath& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::PlayerDeath& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerJoin& a_Packet) {
+	m_Buffer << a_Packet.m_Player;
+}
+
+void Deserializer::DeserializePacketData(data::PlayerJoin& a_Packet) {
+	m_Buffer >> a_Packet.m_Player;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerLeave& a_Packet) {
+	m_Buffer << a_Packet.m_PlayerId;
+}
+
+void Deserializer::DeserializePacketData(data::PlayerLeave& a_Packet) {
+	m_Buffer >> a_Packet.m_PlayerId;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerList& a_Packet) {
+	m_Buffer << a_Packet.m_Players;
+	// m_Buffer << static_cast<std::uint8_t>(a_Packet.m_Players.size());
+	// for (auto player : a_Packet.m_Players) {
+	// 	m_Buffer << player.m_PlayerId << player.m_PlayerName;
+	// }
+}
+
+void Deserializer::DeserializePacketData(data::PlayerList& a_Packet) {
+	m_Buffer >> a_Packet.m_Players;
+	// std::uint8_t playerCount;
+	// m_Buffer >> playerCount;
+	// for (std::uint8_t i = 0; i < playerCount; i++) {
+	// 	PlayerInfo player;
+	// 	m_Buffer >> player.m_PlayerId >> player.m_PlayerName;
+	// 	a_Packet.m_Players.push_back(player);
+	// }
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerStats& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::PlayerStats& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::ServerConfig& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::ServerConfig& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::ServerTps& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::ServerTps& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::UpdateGameState& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::UpdateGameState& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::KeepAlive& a_Packet) {
+	m_Buffer << a_Packet.m_KeepAliveId;
+}
+
+void Deserializer::DeserializePacketData(data::KeepAlive& a_Packet) {
+	m_Buffer >> a_Packet.m_KeepAliveId;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::Disconnect& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::Disconnect& a_Packet) {}
+
+
+
+
+void Serializer::SerializePacketData(const data::ChatMessage& a_Packet) {
+	m_Buffer << a_Packet.m_Text;
+}
+
+void Deserializer::DeserializePacketData(data::ChatMessage& a_Packet) {
+	m_Buffer >> a_Packet.m_Text;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerPositionAndRotation& a_Packet) {
+	m_Buffer << a_Packet.m_Player << a_Packet.m_Position << a_Packet.m_Rotation;
+}
+
+void Deserializer::DeserializePacketData(data::PlayerPositionAndRotation& a_Packet) {
+	m_Buffer >> a_Packet.m_Player >> a_Packet.m_Position >> a_Packet.m_Rotation;
+}
+
+
+
+
+void Serializer::SerializePacketData(const data::PlayerShoot& a_Packet) {}
+
+void Deserializer::DeserializePacketData(data::PlayerShoot& a_Packet) {}
+
+
+
+
+
+}  // namespace PacketSerializer
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/PacketVisitor.cpp

@@ -0,0 +1,11 @@
+#include <blitz/protocol/PacketVisitor.h>
+
+namespace blitz {
+namespace protocol {
+
+void PacketVisitor::Check(const Packet& a_Packet) {
+	a_Packet.Accept(*this);
+}
+
+}  // namespace protocol
+}  // namespace blitz

src/blitz/protocol/Packets.cpp

@@ -0,0 +1,18 @@
+#define BLITZ_INSTANCIATE_PACKETS
+#include <blitz/protocol/Packets.h>
+
+#include <blitz/protocol/PacketVisitor.h>
+
+namespace blitz {
+namespace protocol {
+
+template <PacketType PT, typename Data>
+packets::ConcretePacket<PT, Data>::ConcretePacket(const PacketDataType& a_Data) : m_Data(a_Data) {}
+
+template <PacketType PT, typename Data>
+void packets::ConcretePacket<PT, Data>::Accept(PacketVisitor& a_Visitor) const {
+	a_Visitor.Visit(*this);
+}
+
+}  // namespace protocol
+}  // namespace blitz

src/register_types.cpp

@@ -17,15 +17,15 @@
 using namespace godot;
 
 static void RegisterClasses() {
-	ClassDB::register_class<blitz::Player>();
+	GDREGISTER_CLASS(blitz::Player);
-	ClassDB::register_class<blitz::SpringArmPivot>();
+	GDREGISTER_CLASS(blitz::SpringArmPivot);
-	ClassDB::register_class<blitz::FirstPersonPlayer>();
+	GDREGISTER_CLASS(blitz::FirstPersonPlayer);
-	ClassDB::register_class<blitz::MainMenu>();
+	GDREGISTER_CLASS(blitz::MainMenu);
-	ClassDB::register_class<blitz::Lobby>();
+	GDREGISTER_CLASS(blitz::Lobby);
-	ClassDB::register_class<blitz::World>();
+	GDREGISTER_CLASS(blitz::World);
-	ClassDB::register_class<blitz::Main>();
+	GDREGISTER_CLASS(blitz::Main);
-	ClassDB::register_class<blitz::NetworkInterface>();
+	GDREGISTER_CLASS(blitz::NetworkInterface);
-	ClassDB::register_class<blitz::Server>();
+	GDREGISTER_CLASS(blitz::Server);
 }
 
 void initialize_example_module(ModuleInitializationLevel p_level) {

xmake/godot.lua

@@ -16,7 +16,7 @@ add_rules("mode.debug", "mode.release")
 set_languages("c++20")
 
 -- use latest 4.x version by default
-add_requires("godotcpp4")
+add_requires("godotcpp4 4.2")
 
 
 includes("tasks.lua")

xmake/target.lua

@@ -14,6 +14,8 @@ target(PROJECT_NAME)
     -- more on https://xmake.io/#/manual/project_target?id=targetadd_files
     add_files("../src/**.cpp")
 
+    add_includedirs("../include")
+
     -- change the output name
     set_basename(PROJECT_NAME .. ".$(os)_$(mode)_$(arch)")