feat: Paddle Data Send

.vscode/launch.json

@@ -10,9 +10,9 @@
       "request": "launch",
       "preLaunchTask": "build",
       // If you have changed target frameworks, make sure to update the program path.
-      "program": "${workspaceFolder}/bin/Debug/net8.0/${workspaceFolderBasename}.dll",
+      "program": "${workspaceFolder}/Game/bin/Debug/net8.0/Game.dll",
-      "args": [],
+      "args": ["server"],
-      "cwd": "${workspaceFolder}",
+      "cwd": "${workspaceFolder}/Game",
       // For more information about the 'console' field, see https://aka.ms/VSCode-CS-LaunchJson-Console
       "console": "internalConsole",
       "stopAtEntry": false

.vscode/tasks.json

@@ -9,7 +9,10 @@
         "kind": "build",
         "isDefault": true
       },
-      "label": "build"
+      "label": "build",
+      "options": {
+        "cwd": "${workspaceFolder}/Game"
+      }
     }
   ]
 }

Engine

@@ -1 +1 @@
-Subproject commit ef21cdf2138a2f5107a628c0fe970b88bc03dcfd
+Subproject commit 2cf6135063b12dfff4d2c8391ad8edde806183f0

Game/Abstract/IContentLoader.cs

@@ -0,0 +1,8 @@
+using Microsoft.Xna.Framework.Content;
+
+namespace Pong.Behaviours;
+
+public interface IMonoGameContentLoader
+{
+    void LoadContent(ContentManager content);
+}

Game/Behaviours/BallBehaviour.cs

@@ -1,12 +1,19 @@
 using System;
 
+using Microsoft.Xna.Framework.Audio;
+using Microsoft.Xna.Framework.Content;
+
+using LiteNetLib;
+
 using Syntriax.Engine.Core;
+using Syntriax.Engine.Network;
+using Syntriax.Engine.Network.Abstract;
 using Syntriax.Engine.Physics2D;
 using Syntriax.Engine.Physics2D.Abstract;
 
 namespace Pong.Behaviours;
 
-public class BallBehaviour : BehaviourOverride
+public class BallBehaviour : NetworkBehaviour, IMonoGameContentLoader
 {
     public Vector2D StartDirection { get; private set; } = Vector2D.Zero;
     public float Speed { get; set; } = 500f;
@@ -14,6 +21,13 @@ public class BallBehaviour : BehaviourOverride
 
     private readonly Random random = new();
     private IRigidBody2D rigidBody = null!;
+    private INetworkCommunicator communicator = null!;
+    private SoundEffect soundEffect = null!;
+
+    public void LoadContent(ContentManager content)
+    {
+        soundEffect = content.Load<SoundEffect>("Hit");
+    }
 
     protected override void OnFirstActiveFrame()
     {
@@ -21,11 +35,13 @@ public class BallBehaviour : BehaviourOverride
             throw new Exception($"{nameof(IRigidBody2D)} is missing on {GameObject.Name}.");
         if (!BehaviourController.TryGetBehaviour(out ICollider2D? foundCollider))
             throw new Exception($"{nameof(ICollider2D)} is missing on {GameObject.Name}.");
+        if (!GameObject.GameManager.TryFindBehaviour(out INetworkCommunicator? foundCommunicator))
+            throw new Exception($"{nameof(INetworkCommunicator)} is missing on GameManager.");
 
         foundCollider.OnCollisionDetected += OnCollisionDetected;
 
         rigidBody = foundRigidBody;
-
+        communicator = foundCommunicator;
         if (GameObject.GameManager.TryFindBehaviour(out PongManagerBehaviour? pongManager))
         {
             pongManager.OnReset += ResetBall;
@@ -45,6 +61,8 @@ public class BallBehaviour : BehaviourOverride
         StateEnable.Enabled = true;
         BehaviourController.GameObject.Transform.Position = Vector2D.Zero;
         rigidBody.Velocity = GetRandomDirection() * Speed;
+
+        SendBallData();
     }
 
     private Vector2D GetRandomDirection()
@@ -70,6 +88,27 @@ public class BallBehaviour : BehaviourOverride
             rigidBody.Velocity = information.Left.Transform.Position.FromTo(information.Right.Transform.Position).Normalized * rigidBody.Velocity.Magnitude;
         else
             rigidBody.Velocity = rigidBody.Velocity.Reflect(information.Normal);
+
+        soundEffect.Play();
+
+        SendBallData();
+    }
+
+    private void SendBallData()
+    {
+        if (communicator is not INetworkServer server)
+            return;
+
+        LiteNetLib.Utils.NetDataWriter dataWriter = communicator.GetMessageWriter(this);
+        dataWriter.Put(rigidBody.Transform.Position);
+        dataWriter.Put(rigidBody.Velocity);
+        server.Manager.SendToAll(dataWriter, LiteNetLib.DeliveryMethod.ReliableOrdered);
+    }
+
+    protected override void OnMessageReceived(NetPacketReader reader, NetPeer peer)
+    {
+        rigidBody.Transform.Position = reader.GetVector2D();
+        rigidBody.Velocity = reader.GetVector2D();
     }
 
     public BallBehaviour() { }

Game/Behaviours/KeyboardInputsBehaviour.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-
 using Microsoft.Xna.Framework.Input;
 
 using Syntriax.Engine.Core;
@@ -10,8 +9,8 @@ namespace Pong.Behaviours;
 
 public class KeyboardInputsBehaviour : BehaviourOverride, IButtonInputs<Keys>
 {
-    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>> OnPressed = new(256);
+    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>?> OnPressed = new(256);
-    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>> OnReleased = new(256);
+    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>?> OnReleased = new(256);
 
     private int cachePressedCurrentlyCount = 0;
     private readonly Keys[] cachePressedCurrently = new Keys[256];
@@ -69,7 +68,7 @@ public class KeyboardInputsBehaviour : BehaviourOverride, IButtonInputs<Keys>
             if (WasPressed(currentlyPressedKey))
                 continue;
 
-            action.Invoke(this, currentlyPressedKey);
+            action?.Invoke(this, currentlyPressedKey);
         }
 
         for (int i = 0; i < cachePressedPreviouslyCount; i++)
@@ -82,7 +81,7 @@ public class KeyboardInputsBehaviour : BehaviourOverride, IButtonInputs<Keys>
             if (IsPressed(previouslyPressedKey))
                 continue;
 
-            action.Invoke(this, previouslyPressedKey);
+            action?.Invoke(this, previouslyPressedKey);
         }
 
         Array.Copy(cachePressedCurrently, cachePressedPreviously, cachePressedCurrentlyCount);

Game/Behaviours/MonoGameCamera2DBehaviour.cs

@@ -8,9 +8,9 @@ namespace Pong.Behaviours;
 
 public class MonoGameCamera2DBehaviour(GraphicsDeviceManager Graphics) : BehaviourOverride, ICamera2D
 {
-    public event OnMatrixTransformChangedDelegate? OnMatrixTransformChanged = null;
+    public System.Action<MonoGameCamera2DBehaviour>? OnMatrixTransformChanged { get; set; } = null;
-    public event OnViewportChangedDelegate? OnViewportChanged = null;
+    public System.Action<MonoGameCamera2DBehaviour>? OnViewportChanged { get; set; } = null;
-    public event OnZoomChangedDelegate? OnZoomChanged = null;
+    public System.Action<MonoGameCamera2DBehaviour>? OnZoomChanged { get; set; } = null;
 
     private Matrix _matrixTransform = Matrix.Identity;
 
@@ -72,7 +72,7 @@ public class MonoGameCamera2DBehaviour(GraphicsDeviceManager Graphics) : Behavio
         set => Transform.Rotation = value;
     }
 
-    public event IAssignableTransform.OnTransformAssignedDelegate? OnTransformAssigned { add => GameObject.OnTransformAssigned += value; remove => GameObject.OnTransformAssigned -= value; }
+    System.Action<IAssignableTransform>? IAssignableTransform.OnTransformAssigned { get => GameObject.OnTransformAssigned; set => GameObject.OnTransformAssigned = value; }
     ITransform IAssignableTransform.Transform => GameObject.Transform;
     bool IAssignableTransform.Assign(ITransform transform) => GameObject.Assign(transform);
 
@@ -99,8 +99,4 @@ public class MonoGameCamera2DBehaviour(GraphicsDeviceManager Graphics) : Behavio
             Matrix.CreateScale(Zoom) *
             Matrix.CreateTranslation(new Vector3(_viewport.Width * .5f, _viewport.Height * .5f, 0f));
     }
-
-    public delegate void OnMatrixTransformChangedDelegate(MonoGameCamera2DBehaviour sender);
-    public delegate void OnViewportChangedDelegate(MonoGameCamera2DBehaviour sender);
-    public delegate void OnZoomChangedDelegate(MonoGameCamera2DBehaviour sender);
 }

Game/Behaviours/NetworkedKeyboardInputs.cs

@@ -0,0 +1,154 @@
+using System;
+using System.Collections.Generic;
+using LiteNetLib;
+using Microsoft.Xna.Framework.Input;
+using Syntriax.Engine.Input;
+using Syntriax.Engine.Network;
+
+namespace Pong.Behaviours;
+
+public class NetworkedKeyboardInputs : NetworkBehaviour, IButtonInputs<Keys>
+{
+    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>?> OnPressed = new(256);
+    private readonly Dictionary<Keys, Action<IButtonInputs<Keys>, Keys>?> OnReleased = new(256);
+
+    private int cachePressedCurrentlyCount = 0;
+    private readonly Keys[] cachePressedCurrently = new Keys[256];
+
+    private int cachePressedPreviouslyCount = 0;
+    private readonly Keys[] cachePressedPreviously = new Keys[256];
+
+    public void RegisterOnPress(Keys key, Action<IButtonInputs<Keys>, Keys> callback)
+    {
+        if (OnPressed.TryGetValue(key, out var action))
+        {
+            action += callback;
+            OnPressed.Remove(key);
+            OnPressed.Add(key, action);
+            return;
+        }
+
+        OnPressed.Add(key, callback);
+    }
+
+    public void UnregisterOnPress(Keys key, Action<IButtonInputs<Keys>, Keys> callback)
+    {
+        if (OnPressed.TryGetValue(key, out var action))
+            action -= callback;
+    }
+
+    public void RegisterOnRelease(Keys key, Action<IButtonInputs<Keys>, Keys> callback)
+    {
+        if (OnReleased.TryGetValue(key, out var action))
+        {
+            action += callback;
+            OnReleased.Remove(key);
+            OnReleased.Add(key, action);
+            return;
+        }
+
+        OnReleased.Add(key, callback);
+    }
+
+    public void UnregisterOnRelease(Keys key, Action<IButtonInputs<Keys>, Keys> callback)
+    {
+        if (OnReleased.TryGetValue(key, out var action))
+            action -= callback;
+    }
+
+    protected override void OnUpdate()
+    {
+        if (!IsServer && !LocalAssigned)
+            return;
+
+        KeyboardState keyboardState = Keyboard.GetState();
+        keyboardState.GetPressedKeys(cachePressedCurrently);
+        cachePressedCurrentlyCount = keyboardState.GetPressedKeyCount();
+
+        for (int i = 0; i < cachePressedCurrentlyCount; i++)
+        {
+            Keys currentlyPressedKey = cachePressedCurrently[i];
+
+            if (!OnPressed.TryGetValue(currentlyPressedKey, out var action))
+                continue;
+
+            if (WasPressed(currentlyPressedKey))
+                continue;
+
+            action?.Invoke(this, currentlyPressedKey);
+        }
+
+        for (int i = 0; i < cachePressedPreviouslyCount; i++)
+        {
+            Keys previouslyPressedKey = cachePressedPreviously[i];
+
+            if (!OnReleased.TryGetValue(previouslyPressedKey, out var action))
+                continue;
+
+            if (IsPressed(previouslyPressedKey))
+                continue;
+
+            action?.Invoke(this, previouslyPressedKey);
+        }
+
+        Array.Copy(cachePressedCurrently, cachePressedPreviously, cachePressedCurrentlyCount);
+        cachePressedPreviouslyCount = cachePressedCurrentlyCount;
+    }
+
+    public bool IsPressed(Keys key)
+    {
+        for (int i = 0; i < cachePressedCurrentlyCount; i++)
+            if (cachePressedCurrently[i] == key)
+                return true;
+        return false;
+    }
+
+    public bool WasPressed(Keys key)
+    {
+        for (int i = 0; i < cachePressedPreviouslyCount; i++)
+            if (cachePressedPreviously[i] == key)
+                return true;
+        return false;
+    }
+
+    protected override void OnInitialize()
+    {
+        base.OnInitialize();
+        foreach (Keys key in Enum.GetValues(typeof(Keys)))
+        {
+            RegisterOnPress(key, (keys, keyVal) =>
+            {
+                if (!LocalAssigned && !IsServer)
+                    return;
+
+                var netDataWriter = NetworkCommunicator.GetMessageWriter(this);
+                netDataWriter.Put(true);
+                netDataWriter.Put((int)key);
+                NetworkCommunicator.Manager.SendToAll(netDataWriter, DeliveryMethod.ReliableOrdered);
+            });
+            RegisterOnRelease(key, (keys, keyVal) =>
+            {
+                if (!LocalAssigned && !IsServer)
+                    return;
+
+                var netDataWriter = NetworkCommunicator.GetMessageWriter(this);
+                netDataWriter.Put(false);
+                netDataWriter.Put((int)key);
+                NetworkCommunicator.Manager.SendToAll(netDataWriter, DeliveryMethod.ReliableOrdered);
+            });
+        }
+    }
+
+    protected override void OnMessageReceived(NetPacketReader reader, NetPeer peer)
+    {
+        bool isPressed = reader.GetBool();
+        Keys key = (Keys)reader.GetInt();
+
+        if (isPressed)
+            if (OnPressed.TryGetValue(key, out var action))
+                action?.Invoke(this, key);
+        if (!isPressed)
+            if (OnReleased.TryGetValue(key, out var action))
+                action?.Invoke(this, key);
+    }
+}

Game/Behaviours/PaddleBehaviour.cs

@@ -2,8 +2,13 @@ using System;
 
 using Microsoft.Xna.Framework.Input;
 
+using LiteNetLib;
+using LiteNetLib.Utils;
+
 using Syntriax.Engine.Core;
 using Syntriax.Engine.Input;
+using Syntriax.Engine.Network;
+using Syntriax.Engine.Network.Abstract;
 
 namespace Pong.Behaviours;
 
@@ -19,6 +24,7 @@ public class PaddleBehaviour(Keys Up, Keys Down, float High, float Low, float Sp
     private bool isDownPressed = false;
 
     private IButtonInputs<Keys> inputs = null!;
+    private INetworkCommunicator communicator = null!;
 
     protected override void OnUpdate()
     {
@@ -26,23 +32,33 @@ public class PaddleBehaviour(Keys Up, Keys Down, float High, float Low, float Sp
             return;
 
         if (isUpPressed)
-            GameObject.Transform.Position = GameObject.Transform.Position + Vector2D.Up * (float)Time.Elapsed.TotalSeconds * Speed;
+            MovePaddle(Vector2D.Up * (float)Time.Elapsed.TotalSeconds * Speed);
         else if (isDownPressed)
-            GameObject.Transform.Position = GameObject.Transform.Position + -Vector2D.Up * (float)Time.Elapsed.TotalSeconds * Speed;
+            MovePaddle(-Vector2D.Up * (float)Time.Elapsed.TotalSeconds * Speed);
+    }
 
+    private void MovePaddle(Vector2D vectorToAdd)
+    {
+        GameObject.Transform.Position += vectorToAdd;
         GameObject.Transform.Position = new Vector2D(GameObject.Transform.Position.X, MathF.Max(MathF.Min(GameObject.Transform.Position.Y, High), Low));
     }
 
     protected override void OnFirstActiveFrame()
     {
-        if (!BehaviourController.TryGetBehaviour<IButtonInputs<Keys>>(out var behaviourResult))
+        BehaviourController.TryGetBehaviour<IButtonInputs<Keys>>(out var behaviourResult);
-            inputs = behaviourResult ?? BehaviourController.AddBehaviour<KeyboardInputsBehaviour>();
+        inputs = behaviourResult ?? throw new Exception($"{nameof(IButtonInputs<Keys>)} is missing on {GameObject.Name}.");
+
+        if (!GameObject.GameManager.TryFindBehaviour(out INetworkCommunicator? foundCommunicator))
+            throw new Exception($"{nameof(INetworkCommunicator)} is missing on GameManager.");
 
         inputs.RegisterOnPress(Up, OnUpPressed);
         inputs.RegisterOnRelease(Up, OnUpReleased);
 
         inputs.RegisterOnPress(Down, OnDownPressed);
         inputs.RegisterOnRelease(Down, OnDownReleased);
+
+        communicator = foundCommunicator;
+        communicator.RegisterEntityListener(this, OnDataReceived);
     }
 
     protected override void OnFinalize()
@@ -54,8 +70,32 @@ public class PaddleBehaviour(Keys Up, Keys Down, float High, float Low, float Sp
         inputs.UnregisterOnRelease(Down, OnDownReleased);
     }
 
-    private void OnUpPressed(IButtonInputs<Keys> inputs, Keys keys) => isUpPressed = true;
+    private void UpdateNetwork()
-    private void OnUpReleased(IButtonInputs<Keys> inputs, Keys keys) => isUpPressed = false;
+    {
-    private void OnDownPressed(IButtonInputs<Keys> inputs, Keys keys) => isDownPressed = true;
+        NetDataWriter netDataWriter = communicator.GetEntityWriter(this);
-    private void OnDownReleased(IButtonInputs<Keys> inputs, Keys keys) => isDownPressed = false;
+        netDataWriter.Put(isUpPressed);
+        netDataWriter.Put(isDownPressed);
+        netDataWriter.Put(Transform.Position);
+        communicator.Manager.SendToAll(netDataWriter, DeliveryMethod.ReliableOrdered);
+    }
+
+    private void OnDataReceived(NetPacketReader reader, NetPeer peer)
+    {
+        if (communicator is INetworkServer server)
+        {
+            reader.Get(out isUpPressed);
+            reader.Get(out isDownPressed);
+        }
+        else
+        {
+            reader.Get(out isUpPressed);
+            reader.Get(out isDownPressed);
+            Transform.Position = reader.GetVector2D();
+        }
+    }
+
+    private void OnUpPressed(IButtonInputs<Keys> inputs, Keys keys) { isUpPressed = true; UpdateNetwork(); }
+    private void OnUpReleased(IButtonInputs<Keys> inputs, Keys keys) { isUpPressed = false; UpdateNetwork(); }
+    private void OnDownPressed(IButtonInputs<Keys> inputs, Keys keys) { isDownPressed = true; UpdateNetwork(); }
+    private void OnDownReleased(IButtonInputs<Keys> inputs, Keys keys) { isDownPressed = false; UpdateNetwork(); }
 }

Game/Behaviours/PongManagerBehaviour.cs

@@ -2,16 +2,23 @@ using System;
 
 using Microsoft.Xna.Framework.Input;
 
+using LiteNetLib;
+
 using Syntriax.Engine.Core;
+using Syntriax.Engine.Network;
+using Syntriax.Engine.Network.Abstract;
 
 namespace Pong.Behaviours;
 
-public class PongManagerBehaviour : BehaviourOverride
+public class PongManagerBehaviour : NetworkBehaviour
 {
     public Action<PongManagerBehaviour>? OnReset { get; set; } = null;
     public Action<PongManagerBehaviour>? OnFinished { get; set; } = null;
+    public Action<PongManagerBehaviour>? OnScoresUpdated { get; set; } = null;
     public Action<PongManagerBehaviour>? OnScored { get; set; } = null;
 
+    private INetworkCommunicator communicator = null!;
+
     public int ScoreLeft { get; private set; } = 0;
     public int ScoreRight { get; private set; } = 0;
     public int ScoreSum => ScoreLeft + ScoreRight;
@@ -28,30 +35,43 @@ public class PongManagerBehaviour : BehaviourOverride
         if (!BehaviourController.TryGetBehaviour(out buttonInputs))
             buttonInputs = BehaviourController.AddBehaviour<KeyboardInputsBehaviour>();
 
-        buttonInputs.RegisterOnRelease(Keys.Space, (_, _1) => Reset());
+        if (!GameObject.GameManager.TryFindBehaviour(out INetworkCommunicator? foundCommunicator))
-    }
+            throw new Exception($"{nameof(INetworkCommunicator)} is missing on GameManager.");
 
+        buttonInputs.RegisterOnRelease(Keys.Space, (_, _1) => Reset());
+
+        communicator = foundCommunicator;
+    }
 
     public void ScoreToLeft()
     {
         ScoreLeft++;
+        OnScoresUpdated?.Invoke(this);
         OnScored?.Invoke(this);
 
+        SendData();
+
         CheckFinish();
     }
 
     public void ScoreToRight()
     {
         ScoreRight++;
+        OnScoresUpdated?.Invoke(this);
         OnScored?.Invoke(this);
 
+        SendData();
+
         CheckFinish();
     }
 
     public void Reset()
     {
         ScoreLeft = ScoreRight = 0;
+        OnScoresUpdated?.Invoke(this);
         OnReset?.Invoke(this);
+
+        SendData();
     }
 
     private void CheckFinish()
@@ -61,4 +81,24 @@ public class PongManagerBehaviour : BehaviourOverride
         if (ScoreLeft > halfwayScore || ScoreRight > halfwayScore)
             OnFinished?.Invoke(this);
     }
+
+    private void SendData()
+    {
+        if (communicator is not INetworkServer server)
+            return;
+
+        LiteNetLib.Utils.NetDataWriter dataWriter = communicator.GetMessageWriter(this);
+        dataWriter.Put(ScoreLeft);
+        dataWriter.Put(ScoreRight);
+        server.Manager.SendToAll(dataWriter, LiteNetLib.DeliveryMethod.ReliableOrdered);
+    }
+
+    protected override void OnMessageReceived(NetPacketReader reader, NetPeer peer)
+    {
+        ScoreLeft = reader.GetInt();
+        ScoreRight = reader.GetInt();
+        OnScoresUpdated?.Invoke(this);
+
+        CheckFinish();
+    }
 }

Game/Behaviours/TextScoreBehaviour.cs

@@ -14,8 +14,7 @@ public class TextScoreBehaviour : TextBehaviour
         if (!GameObject.GameManager.TryFindBehaviour(out pongManager))
             return;
 
-        pongManager.OnScored += UpdateScores;
+        pongManager.OnScoresUpdated += UpdateScores;
-        pongManager.OnReset += UpdateScores;
 
         UpdateScores(pongManager);
     }

Game/Content/Content.mgcb

@@ -13,6 +13,12 @@
 
 #---------------------------------- Content ---------------------------------#
 
+#begin Hit.wav
+/importer:WavImporter
+/processor:SoundEffectProcessor
+/processorParam:Quality=Best
+/build:Hit.wav
+
 #begin UbuntuMono.spritefont
 /importer:FontDescriptionImporter
 /processor:FontDescriptionProcessor

Game/Game.csproj

@@ -21,6 +21,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Apos.Shapes" Version="0.2.3" />
+    <PackageReference Include="LiteNetLib" Version="1.2.0" />
     <PackageReference Include="MonoGame.Framework.DesktopGL" Version="3.8.1.303" />
     <PackageReference Include="MonoGame.Content.Builder.Task" Version="3.8.1.303" />
   </ItemGroup>

Game/GamePong.cs

@@ -1,16 +1,19 @@
 using System;
+
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Graphics;
 using Microsoft.Xna.Framework.Input;
 
-using Pong.Behaviours;
 using Apos.Shapes;
 
+using Pong.Behaviours;
+using Syntriax.Engine.Network;
+
 using Syntriax.Engine.Core;
 using Syntriax.Engine.Core.Abstract;
 using Syntriax.Engine.Physics2D;
-using Syntriax.Engine.Physics2D.Primitives;
 using Syntriax.Engine.Physics2D.Abstract;
+using Syntriax.Engine.Physics2D.Primitives;
 
 namespace Pong;
 
@@ -24,6 +27,7 @@ public class GamePong : Game
     private GameManager gameManager = null!;
     private BehaviourCollector<IDisplayableSprite> displayableCollector = null!;
     private BehaviourCollector<IDisplayableShape> displayableShapeCollector = null!;
+    private BehaviourCollector<IMonoGameContentLoader> monoGameContentLoaderCollector = null!;
     private MonoGameCamera2DBehaviour cameraBehaviour = null!;
 
     private PongManagerBehaviour pongManager = null!;
@@ -49,8 +53,11 @@ public class GamePong : Game
         gameManager = new();
         displayableCollector = new(gameManager);
         displayableShapeCollector = new(gameManager);
+        monoGameContentLoaderCollector = new(gameManager);
         physicsEngine = new PhysicsEngine2DCollector(gameManager) { IterationPerStep = 3 };
 
+        monoGameContentLoaderCollector.OnCollected += (_, cached) => cached.LoadContent(Content);
+
         gameManager.Initialize();
 
         base.Initialize();
@@ -64,58 +71,83 @@ public class GamePong : Game
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectCamera = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Camera"); ;
+        string[] commandLineArguments = Environment.GetCommandLineArgs();
+        if (commandLineArguments.Length != 1)
+        {
+            if (commandLineArguments[1].Equals("server", StringComparison.OrdinalIgnoreCase))
+            {
+                gameManager.InstantiateGameObject().BehaviourController.AddBehaviour<NetworkServer>().Start(8888, 2);
+                Window.Title = "Pong - Server";
+            }
+            else
+            {
+                Window.Title = $"Pong - Client -> {commandLineArguments[1]}";
+                gameManager.InstantiateGameObject().BehaviourController.AddBehaviour<NetworkClient>().Connect(commandLineArguments[1], 8888);
+            }
+        }
+        else
+        {
+            gameManager.InstantiateGameObject().BehaviourController.AddBehaviour<NetworkClient>().Connect("127.0.0.1", 8888);
+            Window.Title = $"Pong - Client -> 127.0.0.1";
+        }
+
+        ////////////////////////////////////////////////////////////////////////////////////
+
+        IGameObject gameObjectCamera = gameManager.InstantiateGameObject().SetGameObject("Camera"); ;
         gameObjectCamera.BehaviourController.AddBehaviour<CameraController>();
         cameraBehaviour = gameObjectCamera.BehaviourController.AddBehaviour<MonoGameCamera2DBehaviour>(graphics);
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectPongManager = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Pong Game Manager");
+        IGameObject gameObjectPongManager = gameManager.InstantiateGameObject().SetGameObject("Pong Game Manager");
         pongManager = gameObjectPongManager.BehaviourController.AddBehaviour<PongManagerBehaviour>(5);
+        pongManager.Id = "pongManager";
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectBall = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Ball");
+        IGameObject gameObjectBall = gameManager.InstantiateGameObject().SetGameObject("Ball");
         gameObjectBall.Transform.SetTransform(position: new Vector2D(0, 0f), scale: new Vector2D(10f, 10f));
 
         gameObjectBall.BehaviourController.AddBehaviour<CircleBehaviour>(new Circle(Vector2D.Zero, 1f));
-        gameObjectBall.BehaviourController.AddBehaviour<BallBehaviour>();
+        gameObjectBall.BehaviourController.AddBehaviour<BallBehaviour>().Id = "ball";
         gameObjectBall.BehaviourController.AddBehaviour<RigidBody2D>();
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectLeftPaddle = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Left Paddle");
+        IGameObject gameObjectLeftPaddle = gameManager.InstantiateGameObject().SetGameObject("Left Paddle");
         gameObjectLeftPaddle.Transform.SetTransform(position: new Vector2D(-468f, 0f), scale: new Vector2D(15f, 60f));
 
-        gameObjectLeftPaddle.BehaviourController.AddBehaviour<PaddleBehaviour>(Keys.W, Keys.S, 228f, -228f, 400f);
+        gameObjectLeftPaddle.BehaviourController.AddBehaviour<NetworkedKeyboardInputs>().Id = "leftPaddleInput";
+        gameObjectLeftPaddle.BehaviourController.AddBehaviour<PaddleBehaviour>(Keys.W, Keys.S, 228f, -228f, 400f).Id = "leftPaddle";
         gameObjectLeftPaddle.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
         gameObjectLeftPaddle.BehaviourController.AddBehaviour<RigidBody2D>().IsStatic = true;
 
-        IGameObject gameObjectRightPaddle = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Right Paddle");
+        IGameObject gameObjectRightPaddle = gameManager.InstantiateGameObject().SetGameObject("Right Paddle");
         gameObjectRightPaddle.Transform.SetTransform(position: new Vector2D(468f, 0f), scale: new Vector2D(15f, 60f));
-        gameObjectRightPaddle.BehaviourController.AddBehaviour<PaddleBehaviour>(Keys.Up, Keys.Down, 228f, -228f, 400f);
+        gameObjectRightPaddle.BehaviourController.AddBehaviour<NetworkedKeyboardInputs>().Id = "rightPaddleInput";
+        gameObjectRightPaddle.BehaviourController.AddBehaviour<PaddleBehaviour>(Keys.Up, Keys.Down, 228f, -228f, 400f).Id = "rightPaddle";
         gameObjectRightPaddle.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
         gameObjectRightPaddle.BehaviourController.AddBehaviour<RigidBody2D>().IsStatic = true;
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectWallTop = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Wall Top");
+        IGameObject gameObjectWallTop = gameManager.InstantiateGameObject().SetGameObject("Wall Top");
         gameObjectWallTop.Transform.SetTransform(position: new Vector2D(0f, 308f), scale: new Vector2D(552f, 20f));
         gameObjectWallTop.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
         gameObjectWallTop.BehaviourController.AddBehaviour<RigidBody2D>().IsStatic = true;
 
-        IGameObject gameObjectWallBottom = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Wall Bottom");
+        IGameObject gameObjectWallBottom = gameManager.InstantiateGameObject().SetGameObject("Wall Bottom");
         gameObjectWallBottom.Transform.SetTransform(position: new Vector2D(0f, -308f), scale: new Vector2D(552f, 20f));
         gameObjectWallBottom.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
         gameObjectWallBottom.BehaviourController.AddBehaviour<RigidBody2D>().IsStatic = true;
 
-        IGameObject gameObjectWallRight = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Wall Right");
+        IGameObject gameObjectWallRight = gameManager.InstantiateGameObject().SetGameObject("Wall Right");
         gameObjectWallRight.Transform.SetTransform(position: new Vector2D(532f, 0f), scale: new Vector2D(20f, 328f));
         gameObjectWallRight.BehaviourController.AddBehaviour<WallScoreBehaviour>((Action)pongManager.ScoreToLeft);
         gameObjectWallRight.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
         gameObjectWallRight.BehaviourController.AddBehaviour<RigidBody2D>().IsStatic = true;
 
-        IGameObject gameObjectWallLeft = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Wall Left");
+        IGameObject gameObjectWallLeft = gameManager.InstantiateGameObject().SetGameObject("Wall Left");
         gameObjectWallLeft.Transform.SetTransform(position: new Vector2D(-532f, 0f), scale: new Vector2D(20f, 328f));
         gameObjectWallLeft.BehaviourController.AddBehaviour<WallScoreBehaviour>((Action)pongManager.ScoreToRight);
         gameObjectWallLeft.BehaviourController.AddBehaviour<ShapeBehaviour>(Shape.Box);
@@ -123,11 +155,11 @@ public class GamePong : Game
 
         ////////////////////////////////////////////////////////////////////////////////////
 
-        IGameObject gameObjectLeftScoreText = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Score Left");
+        IGameObject gameObjectLeftScoreText = gameManager.InstantiateGameObject().SetGameObject("Score Left");
         gameObjectLeftScoreText.Transform.SetTransform(position: new Vector2D(-250f, 250f), scale: Vector2D.One * .25f);
         gameObjectLeftScoreText.BehaviourController.AddBehaviour<TextScoreBehaviour>(true, spriteFont);
 
-        IGameObject gameObjectRightScoreText = gameManager.InstantiateGameObject<GameObject>().SetGameObject("Score Right");
+        IGameObject gameObjectRightScoreText = gameManager.InstantiateGameObject().SetGameObject("Score Right");
         gameObjectRightScoreText.Transform.SetTransform(position: new Vector2D(250f, 250f), scale: Vector2D.One * .25f);
         gameObjectRightScoreText.BehaviourController.AddBehaviour<TextScoreBehaviour>(false, spriteFont);
     }

Game/Network/Abstract/INetworkBehaviour.cs

@@ -0,0 +1,18 @@
+using Syntriax.Engine.Core.Abstract;
+
+namespace Syntriax.Engine.Network.Abstract;
+
+public interface INetworkBehaviour : IBehaviour
+{
+    int NetworkId { get; }
+
+    bool LocalAssigned { get; }
+
+    bool IsServer { get; }
+    bool IsClient { get; }
+
+    INetworkCommunicator NetworkCommunicator { get; }
+
+    public void RequestAssignment();
+    public void ReleaseAssignment();
+}

Game/Network/Abstract/INetworkClient.cs

@@ -0,0 +1,6 @@
+namespace Syntriax.Engine.Network.Abstract;
+
+public interface INetworkClient : INetworkCommunicator
+{
+    void Connect(string address, int port, string? password = null);
+}

Game/Network/Abstract/INetworkCommunicator.cs

@@ -0,0 +1,22 @@
+using System;
+
+using LiteNetLib;
+using LiteNetLib.Utils;
+
+using Syntriax.Engine.Core.Abstract;
+
+namespace Syntriax.Engine.Network.Abstract;
+
+public interface INetworkCommunicator
+{
+    EventBasedNetListener Listener { get; }
+    NetManager Manager { get; }
+
+    void PollEvents();
+    void Stop();
+
+    void RegisterEntityListener(IEntity entity, Action<NetPacketReader, NetPeer> onDataReceived);
+    void UnregisterEntityListener(IEntity entity);
+    NetDataWriter GetEntityWriter(IEntity entity);
+    NetDataWriter GetMessageWriter(IEntity entity);
+}

Game/Network/Abstract/INetworkEntity.cs

@@ -0,0 +1,11 @@
+using System;
+
+namespace Syntriax.Engine.Network.Abstract;
+
+internal interface INetworkEntity
+{
+    Action<INetworkEntity, int> OnNetworkIdChanged { get; set; }
+    int NetworkId { get; set; }
+
+    void SetNetworkId(int id);
+}

Game/Network/Abstract/INetworkManager.cs

@@ -0,0 +1,10 @@
+namespace Syntriax.Engine.Network.Abstract;
+
+public interface INetworkManager
+{
+    // Action<IGameObject>? OnNetworkGameObjectInstantiated { get; set; }
+
+    INetworkCommunicator NetworkCommunicator { get; }
+
+    // Task<T> Instantiate<T>(params object?[]? args) where T : class, IGameObject;
+}

Game/Network/Abstract/INetworkServer.cs

@@ -0,0 +1,10 @@
+namespace Syntriax.Engine.Network.Abstract;
+
+public interface INetworkServer : INetworkCommunicator
+{
+    string Password { get; }
+    int MaxConnectionCount { get; }
+    int Port { get; }
+
+    void Start(int port, int maxConnectionCount, string? password = null);
+}

Game/Network/NetworkBase.cs

@@ -0,0 +1,81 @@
+using System;
+using System.Collections.Generic;
+
+using LiteNetLib;
+using LiteNetLib.Utils;
+
+using Syntriax.Engine.Core;
+using Syntriax.Engine.Core.Abstract;
+using Syntriax.Engine.Network.Abstract;
+
+namespace Syntriax.Engine.Network;
+
+public abstract class NetworkBase : BehaviourOverride, INetworkCommunicator
+{
+    public EventBasedNetListener Listener { get; private set; } = null!;
+    public NetManager Manager { get; private set; } = null!;
+
+    public NetworkBase()
+    {
+        Priority = 10;
+
+        Listener = new EventBasedNetListener();
+        Manager = new NetManager(Listener);
+
+        Listener.NetworkReceiveEvent += NetworkReceiveEvent;
+    }
+
+    public void PollEvents() => Manager.PollEvents();
+    public void Stop() => Manager.Stop();
+
+    protected override void OnUpdate() => PollEvents();
+    protected override void OnFinalize() => Stop();
+
+    private readonly Dictionary<string, Action<NetPacketReader, NetPeer>> callbacks = new(32);
+
+    private void NetworkReceiveEvent(NetPeer peer, NetPacketReader reader, byte channel, DeliveryMethod deliveryMethod)
+    {
+        if (callbacks.TryGetValue(reader.GetString(), out var action))
+            action?.Invoke(reader, peer);
+
+        reader.Recycle();
+    }
+
+    public void RegisterEntityListener(IEntity entity, Action<NetPacketReader, NetPeer> onDataReceived)
+    {
+        if (callbacks.ContainsKey(entity.Id))
+            return;
+
+        callbacks.Add(entity.Id, onDataReceived);
+        entity.OnIdChanged += OnEntityIdChanged;
+    }
+
+    public void UnregisterEntityListener(IEntity entity)
+    {
+        if (!callbacks.Remove(entity.Id))
+            return;
+
+        entity.OnIdChanged -= OnEntityIdChanged;
+    }
+
+    public NetDataWriter GetMessageWriter(IEntity entity)
+    {
+        NetDataWriter netDataWriter = GetEntityWriter(entity);
+        netDataWriter.Put((int)MessageType.Message);
+        return netDataWriter;
+    }
+
+    public NetDataWriter GetEntityWriter(IEntity entity)
+    {
+        NetDataWriter netDataWriter = new();
+        netDataWriter.Put(entity.Id);
+        return netDataWriter;
+    }
+
+    private void OnEntityIdChanged(IEntity entity, string previousId)
+    {
+        var action = callbacks[previousId];
+        callbacks.Remove(previousId);
+        callbacks.Add(entity.Id, action);
+    }
+}

Game/Network/NetworkBehaviour.cs

@@ -0,0 +1,99 @@
+using System;
+
+using LiteNetLib;
+
+using Syntriax.Engine.Core;
+using Syntriax.Engine.Network.Abstract;
+
+namespace Syntriax.Engine.Network;
+
+public abstract class NetworkBehaviour : BehaviourOverride, INetworkBehaviour
+{
+    public int NetworkId { get; private set; } = 0;
+
+    public bool LocalAssigned { get; private set; } = false;
+
+    public bool IsServer { get; private set; } = false;
+    public bool IsClient { get; private set; } = false;
+
+    public INetworkCommunicator NetworkCommunicator { get; private set; } = null!;
+
+    protected override void OnInitialize()
+    {
+        NetworkCommunicator = BehaviourController.GetBehaviourInParent<INetworkCommunicator>()
+                              ?? GameObject.GameManager.FindBehaviour<INetworkCommunicator>()
+                              ?? throw new Exception($"Could not find an {nameof(INetworkCommunicator)}.");
+
+        NetworkCommunicator.RegisterEntityListener(this, OnMessageReceivedInternal);
+
+        if (NetworkCommunicator is INetworkClient client)
+        {
+            IsClient = true;
+            return;
+        }
+
+        IsServer = true;
+        LocalAssigned = true;
+    }
+
+    public void ReleaseAssignment()
+    {
+        if (IsServer)
+            return;
+
+        var netDataWriter = NetworkCommunicator.GetEntityWriter(this);
+        netDataWriter.Put((int)MessageType.AssignmentRelease);
+        NetworkCommunicator.Manager.SendToAll(netDataWriter, DeliveryMethod.ReliableOrdered);
+    }
+
+    public void RequestAssignment()
+    {
+        if (IsServer)
+            return;
+
+        var netDataWriter = NetworkCommunicator.GetEntityWriter(this);
+        netDataWriter.Put((int)MessageType.AssignmentRequest);
+        NetworkCommunicator.Manager.SendToAll(netDataWriter, DeliveryMethod.ReliableOrdered);
+    }
+
+    protected abstract void OnMessageReceived(NetPacketReader reader, NetPeer peer);
+    private void OnMessageReceivedInternal(NetPacketReader reader, NetPeer peer)
+    {
+        MessageType messageType = (MessageType)reader.GetInt();
+
+        if (IsServer)
+        {
+            switch (messageType)
+            {
+                case MessageType.Message: OnMessageReceived(reader, peer); break;
+                case MessageType.AssignmentRequest:
+                case MessageType.AssignmentRelease:
+                    var netDataWriter = NetworkCommunicator.GetEntityWriter(this);
+                    netDataWriter.Put((int)(messageType == MessageType.AssignmentRequest ? MessageType.Assigned : MessageType.Unassigned));
+                    peer.Send(netDataWriter, DeliveryMethod.ReliableOrdered);
+                    break;
+                default:
+                    break;
+            }
+            return;
+        }
+
+        switch (messageType)
+        {
+            case MessageType.Message: OnMessageReceived(reader, peer); break;
+            case MessageType.Assigned: LocalAssigned = true; break;
+            case MessageType.Unassigned: LocalAssigned = false; break;
+            default:
+                break;
+        }
+    }
+}
+
+internal enum MessageType
+{
+    Message,
+    AssignmentRequest,
+    AssignmentRelease,
+    Assigned,
+    Unassigned,
+}

Game/Network/NetworkClient.cs

@@ -0,0 +1,12 @@
+using Syntriax.Engine.Network.Abstract;
+
+namespace Syntriax.Engine.Network;
+
+public class NetworkClient : NetworkBase, INetworkClient
+{
+    public void Connect(string address, int port, string? password = null)
+    {
+        Manager.Start();
+        Manager.Connect(address, port, password ?? string.Empty);
+    }
+}

Game/Network/NetworkExtensions.cs

@@ -0,0 +1,20 @@
+using LiteNetLib;
+using LiteNetLib.Utils;
+
+using Syntriax.Engine.Core;
+
+namespace Syntriax.Engine.Network;
+
+public static class NetworkExtensions
+{
+    public static Vector2D GetVector2D(this NetPacketReader reader)
+        => new(reader.GetFloat(), reader.GetFloat());
+    public static void GetVector2D(this NetPacketReader reader, out Vector2D vector2D)
+        => vector2D = new(reader.GetFloat(), reader.GetFloat());
+
+    public static void Put(this NetDataWriter writer, Vector2D vector)
+    {
+        writer.Put(vector.X);
+        writer.Put(vector.Y);
+    }
+}

Game/Network/NetworkManager.cs

@@ -0,0 +1,31 @@
+using LiteNetLib;
+using Syntriax.Engine.Core;
+
+using Syntriax.Engine.Network.Abstract;
+
+namespace Syntriax.Engine.Network;
+
+public class NetworkManager : NetworkBehaviour, INetworkManager
+{
+    private BehaviourCollector<INetworkEntity> entities = null!;
+
+    private static int networkIdIndex = 0;
+
+    protected override void OnInitialize()
+    {
+        base.OnInitialize();
+
+        ((INetworkEntity)this).SetNetworkId(networkIdIndex++);
+
+        entities = new(GameObject.GameManager);
+        foreach (var entity in entities)
+            entity.SetNetworkId(networkIdIndex++);
+
+        entities.OnCollected += OnCollected;
+    }
+
+    private void OnCollected(BehaviourCollector<INetworkEntity> collector, INetworkEntity entity)
+        => entity.SetNetworkId(networkIdIndex++);
+
+    protected override void OnMessageReceived(NetPacketReader reader, NetPeer peer) { }
+}

Game/Network/NetworkServer.cs

@@ -0,0 +1,30 @@
+using Syntriax.Engine.Network.Abstract;
+
+namespace Syntriax.Engine.Network;
+
+public class NetworkServer : NetworkBase, INetworkServer
+{
+    public string Password { get; private set; } = string.Empty;
+    public int MaxConnectionCount { get; private set; } = 0;
+    public int Port { get; private set; } = 8888;
+
+    public NetworkServer() : base()
+    {
+        Listener.ConnectionRequestEvent += request =>
+        {
+            if (Manager.ConnectedPeersCount < MaxConnectionCount)
+                request.AcceptIfKey(Password);
+            else
+                request.Reject();
+        };
+    }
+
+    public void Start(int port, int maxConnectionCount, string? password = null)
+    {
+        Password = password ?? string.Empty;
+        MaxConnectionCount = maxConnectionCount;
+        Port = port;
+
+        Manager.Start(port);
+    }
+}