fix: coroutine managers now handle exceptions

This coroutine manager allows for nested IEnumerators, however it is experimental at the moment.

Engine.Core/Abstract/ICamera.cs

@@ -5,6 +5,11 @@ namespace Engine.Core;
 /// </summary>
 public interface ICamera
 {
+    /// <summary>
+    /// The viewport of the <see cref="ICamera"/>.
+    /// </summary>
+    Vector2D Viewport { get; }
+
     /// <summary>
     /// View <see cref="Matrix4x4"/> of the <see cref="ICamera"/>.
     /// </summary>

Engine.Core/Config/BasicConfiguration.cs

@@ -0,0 +1,51 @@
+using System.Collections.Generic;
+
+namespace Engine.Core.Config;
+
+public class BasicConfiguration : IConfiguration
+{
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnAdded { get; } = new();
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnSet { get; } = new();
+    public Event<IConfiguration, IConfiguration.ConfigUpdateArguments> OnRemoved { get; } = new();
+
+    private readonly Dictionary<string, object?> values = [];
+
+    public IReadOnlyDictionary<string, object?> Values => values;
+
+    public T Get<T>(string key, T defaultValue) => Get<T>(key) ?? defaultValue;
+    public T? Get<T>(string key)
+    {
+        if (!values.TryGetValue(key, out object? value))
+            return default;
+
+        if (value is T castedObject)
+            return castedObject;
+
+        try { return (T?)System.Convert.ChangeType(value, typeof(T)); } catch { }
+
+        return default;
+    }
+
+    public object? Get(string key)
+    {
+        values.TryGetValue(key, out object? value);
+        return value;
+    }
+
+    public bool Has(string key) => values.ContainsKey(key);
+
+    public void Remove<T>(string key)
+    {
+        if (values.Remove(key))
+            OnRemoved.Invoke(this, new(key));
+    }
+
+    public void Set<T>(string key, T value)
+    {
+        if (!values.TryAdd(key, value))
+            values[key] = value;
+        else
+            OnAdded.Invoke(this, new(key));
+        OnSet.Invoke(this, new(key));
+    }
+}

Engine.Core/Config/ConfigurationExtensions.cs

@@ -0,0 +1,8 @@
+using Engine.Core.Exceptions;
+
+namespace Engine.Core.Config;
+
+public static class ConfigurationExtensions
+{
+    public static T GetRequired<T>(this IConfiguration configuration, string key) => configuration.Get<T>(key) ?? throw new NotFoundException($"Type of {typeof(T).FullName} with the key {key} was not present in the {configuration.GetType().FullName}");
+}

Engine.Core/Config/IConfiguration.cs

@@ -0,0 +1,24 @@
+using System.Collections.Generic;
+
+namespace Engine.Core.Config;
+
+public interface IConfiguration
+{
+    static IConfiguration System { get; set; } = new SystemConfiguration();
+    static IConfiguration Shared { get; set; } = new BasicConfiguration();
+
+    Event<IConfiguration, ConfigUpdateArguments> OnAdded { get; }
+    Event<IConfiguration, ConfigUpdateArguments> OnSet { get; }
+    Event<IConfiguration, ConfigUpdateArguments> OnRemoved { get; }
+
+    IReadOnlyDictionary<string, object?> Values { get; }
+
+    bool Has(string key);
+    object? Get(string key);
+    T Get<T>(string key, T defaultValue);
+    T? Get<T>(string key);
+    void Set<T>(string key, T value);
+    void Remove<T>(string key);
+
+    readonly record struct ConfigUpdateArguments(string Key);
+}

Engine.Core/Config/SystemConfiguration.cs

@@ -0,0 +1,11 @@
+namespace Engine.Core.Config;
+
+public class SystemConfiguration : BasicConfiguration, IConfiguration
+{
+    public SystemConfiguration()
+    {
+        foreach (System.Collections.DictionaryEntry entry in System.Environment.GetEnvironmentVariables())
+            if (entry is { Key: string key, Value: not null })
+                Set(key, entry.Value);
+    }
+}

Engine.Core/Debug/LoggerBase.cs

@@ -4,7 +4,7 @@ namespace Engine.Core.Debug;
 
 public abstract class LoggerBase : ILogger
 {
-    public ILogger.Level FilterLevel { get; set; } = ILogger.Level.Trace;
+    public ILogger.Level FilterLevel { get; set; } = ILogger.Level.Info;
 
     public void Log(string message, ILogger.Level level = ILogger.Level.Info, bool force = false)
     {

Engine.Core/Debug/RotatingFileLogger.cs

@@ -55,7 +55,7 @@ public class RotatingFileLogger : ILogger
     private static void RotateLastLogs(string directory, string prefix, int rotateLength)
     {
         IOrderedEnumerable<string> logs = System.IO.Directory.GetFiles(directory, $"{prefix}*.log")
-            .OrderBy(File.GetCreationTime);
+            .OrderByDescending(File.GetCreationTime);
 
         foreach (string file in logs.Skip(rotateLength))
             try

Engine.Core/Extensions/IdentifiableExtensions.cs

@@ -0,0 +1,12 @@
+namespace Engine.Core;
+
+public static class IdentifiableExtensions
+{
+    public static bool IsIdentical(this IIdentifiable? left, IIdentifiable? right)
+    {
+        if (left == null || right == null)
+            return false;
+
+        return left?.Id?.CompareTo(right?.Id) == 0;
+    }
+}

Engine.Core/Helpers/Event.cs

@@ -58,6 +58,9 @@ public class Event
 
     public ILogger Logger { get; set => field = value ?? ILogger.Shared; } = ILogger.Shared;
 
+    private int currentOnceCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+    private int currentCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+
     private readonly List<ListenerData> listeners = null!;
     private readonly List<ListenerData> onceListeners = null!;
 
@@ -74,6 +77,9 @@ public class Event
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentCallIndex)
+            currentCallIndex++;
+
         listeners.Insert(insertIndex, listenerData);
     }
 
@@ -90,6 +96,9 @@ public class Event
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentOnceCallIndex)
+            currentOnceCallIndex++;
+
         onceListeners.Insert(insertIndex, listenerData);
     }
 
@@ -103,6 +112,8 @@ public class Event
             if (listeners[i].Callback == listener)
             {
                 listeners.RemoveAt(i);
+                if (i < currentCallIndex)
+                    currentCallIndex--;
                 return;
             }
     }
@@ -117,6 +128,8 @@ public class Event
             if (onceListeners[i].Callback == listener)
             {
                 onceListeners.RemoveAt(i);
+                if (i < currentOnceCallIndex)
+                    currentOnceCallIndex--;
                 return;
             }
     }
@@ -131,23 +144,23 @@ public class Event
     /// </summary>
     public void Invoke()
     {
-        for (int i = listeners.Count - 1; i >= 0; i--)
-            try { listeners[i].Callback.Invoke(); }
+        for (currentCallIndex = listeners.Count - 1; currentCallIndex >= 0; currentCallIndex--)
+            try { listeners[currentCallIndex].Callback.Invoke(); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{listeners[i].Callback.Method.DeclaringType?.FullName}.{listeners[i].Callback.Method.Name}()";
-                EventHelpers.LogInvocationException(listeners[i].Callback.Target ?? this, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{listeners[currentCallIndex].Callback.Method.DeclaringType?.FullName}.{listeners[currentCallIndex].Callback.Method.Name}()";
+                EventHelpers.LogInvocationException(listeners[currentCallIndex].Callback.Target ?? this, Logger, exception, methodCallRepresentation);
             }
 
-        for (int i = onceListeners.Count - 1; i >= 0; i--)
+        for (currentOnceCallIndex = onceListeners.Count - 1; currentOnceCallIndex >= 0; currentOnceCallIndex--)
         {
-            try { onceListeners[i].Callback.Invoke(); }
+            try { onceListeners[currentOnceCallIndex].Callback.Invoke(); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{onceListeners[i].Callback.Method.DeclaringType?.FullName}.{onceListeners[i].Callback.Method.Name}()";
-                EventHelpers.LogInvocationException(onceListeners[i].Callback.Target ?? this, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{onceListeners[currentOnceCallIndex].Callback.Method.DeclaringType?.FullName}.{onceListeners[currentOnceCallIndex].Callback.Method.Name}()";
+                EventHelpers.LogInvocationException(onceListeners[currentOnceCallIndex].Callback.Target ?? this, Logger, exception, methodCallRepresentation);
             }
-            onceListeners.RemoveAt(i);
+            onceListeners.RemoveAt(currentOnceCallIndex);
         }
     }
 
@@ -216,6 +229,9 @@ public class Event<TSender> where TSender : class
 
     public ILogger Logger { get; set => field = value ?? ILogger.Shared; } = ILogger.Shared;
 
+    private int currentOnceCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+    private int currentCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+
     private readonly List<ListenerData> listeners = null!;
     private readonly List<ListenerData> onceListeners = null!;
 
@@ -232,6 +248,9 @@ public class Event<TSender> where TSender : class
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentCallIndex)
+            currentCallIndex++;
+
         listeners.Insert(insertIndex, listenerData);
     }
 
@@ -248,6 +267,9 @@ public class Event<TSender> where TSender : class
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentOnceCallIndex)
+            currentOnceCallIndex++;
+
         onceListeners.Insert(insertIndex, listenerData);
     }
 
@@ -261,6 +283,8 @@ public class Event<TSender> where TSender : class
             if (listeners[i].Callback == listener)
             {
                 listeners.RemoveAt(i);
+                if (i < currentCallIndex)
+                    currentCallIndex--;
                 return;
             }
     }
@@ -275,6 +299,8 @@ public class Event<TSender> where TSender : class
             if (onceListeners[i].Callback == listener)
             {
                 onceListeners.RemoveAt(i);
+                if (i < currentOnceCallIndex)
+                    currentOnceCallIndex--;
                 return;
             }
     }
@@ -290,23 +316,23 @@ public class Event<TSender> where TSender : class
     /// <param name="sender">The caller that's triggering this event.</param>
     public void Invoke(TSender sender)
     {
-        for (int i = listeners.Count - 1; i >= 0; i--)
-            try { listeners[i].Callback.Invoke(sender); }
+        for (currentCallIndex = listeners.Count - 1; currentCallIndex >= 0; currentCallIndex--)
+            try { listeners[currentCallIndex].Callback.Invoke(sender); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{listeners[i].Callback.Method.DeclaringType?.FullName}.{listeners[i].Callback.Method.Name}({sender})";
-                EventHelpers.LogInvocationException(listeners[i].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{listeners[currentCallIndex].Callback.Method.DeclaringType?.FullName}.{listeners[currentCallIndex].Callback.Method.Name}({sender})";
+                EventHelpers.LogInvocationException(listeners[currentCallIndex].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
             }
 
-        for (int i = onceListeners.Count - 1; i >= 0; i--)
+        for (currentOnceCallIndex = onceListeners.Count - 1; currentOnceCallIndex >= 0; currentOnceCallIndex--)
         {
-            try { onceListeners[i].Callback.Invoke(sender); }
+            try { onceListeners[currentOnceCallIndex].Callback.Invoke(sender); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{onceListeners[i].Callback.Method.DeclaringType?.FullName}.{onceListeners[i].Callback.Method.Name}({sender})";
-                EventHelpers.LogInvocationException(onceListeners[i].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{onceListeners[currentOnceCallIndex].Callback.Method.DeclaringType?.FullName}.{onceListeners[currentOnceCallIndex].Callback.Method.Name}({sender})";
+                EventHelpers.LogInvocationException(onceListeners[currentOnceCallIndex].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
             }
-            onceListeners.RemoveAt(i);
+            onceListeners.RemoveAt(currentOnceCallIndex);
         }
     }
 
@@ -382,6 +408,9 @@ public class Event<TSender, TArguments> where TSender : class
 
     public ILogger Logger { get; set => field = value ?? ILogger.Shared; } = ILogger.Shared;
 
+    private int currentOnceCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+    private int currentCallIndex = -1; // These are for the purpose of if a listener is added/removed during invocation the index is dynamically updated so no missing/duplicate invocations happen.
+
     private readonly List<ListenerData> listeners = null!;
     private readonly List<ListenerData> onceListeners = null!;
 
@@ -398,6 +427,9 @@ public class Event<TSender, TArguments> where TSender : class
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentCallIndex)
+            currentCallIndex++;
+
         listeners.Insert(insertIndex, listenerData);
     }
 
@@ -414,6 +446,9 @@ public class Event<TSender, TArguments> where TSender : class
         if (insertIndex < 0)
             insertIndex = ~insertIndex;
 
+        if (insertIndex < currentOnceCallIndex)
+            currentOnceCallIndex++;
+
         onceListeners.Insert(insertIndex, listenerData);
     }
 
@@ -427,6 +462,8 @@ public class Event<TSender, TArguments> where TSender : class
             if (listeners[i].Callback == listener)
             {
                 listeners.RemoveAt(i);
+                if (i < currentCallIndex)
+                    currentCallIndex--;
                 return;
             }
     }
@@ -441,6 +478,8 @@ public class Event<TSender, TArguments> where TSender : class
             if (onceListeners[i].Callback == listener)
             {
                 onceListeners.RemoveAt(i);
+                if (i < currentOnceCallIndex)
+                    currentOnceCallIndex--;
                 return;
             }
     }
@@ -457,23 +496,23 @@ public class Event<TSender, TArguments> where TSender : class
     /// <param name="args">The arguments provided for this event.</param>
     public void Invoke(TSender sender, TArguments args)
     {
-        for (int i = listeners.Count - 1; i >= 0; i--)
-            try { listeners[i].Callback.Invoke(sender, args); }
+        for (currentCallIndex = listeners.Count - 1; currentCallIndex >= 0; currentCallIndex--)
+            try { listeners[currentCallIndex].Callback.Invoke(sender, args); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{listeners[i].Callback.Method.DeclaringType?.FullName}.{listeners[i].Callback.Method.Name}({sender}, {args})";
-                EventHelpers.LogInvocationException(listeners[i].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{listeners[currentCallIndex].Callback.Method.DeclaringType?.FullName}.{listeners[currentCallIndex].Callback.Method.Name}({sender}, {args})";
+                EventHelpers.LogInvocationException(listeners[currentCallIndex].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
             }
 
-        for (int i = onceListeners.Count - 1; i >= 0; i--)
+        for (currentOnceCallIndex = onceListeners.Count - 1; currentOnceCallIndex >= 0; currentOnceCallIndex--)
         {
-            try { onceListeners[i].Callback.Invoke(sender, args); }
+            try { onceListeners[currentOnceCallIndex].Callback.Invoke(sender, args); }
             catch (Exception exception)
             {
-                string methodCallRepresentation = $"{onceListeners[i].Callback.Method.DeclaringType?.FullName}.{onceListeners[i].Callback.Method.Name}({sender}, {args})";
-                EventHelpers.LogInvocationException(onceListeners[i].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
+                string methodCallRepresentation = $"{onceListeners[currentOnceCallIndex].Callback.Method.DeclaringType?.FullName}.{onceListeners[currentOnceCallIndex].Callback.Method.Name}({sender}, {args})";
+                EventHelpers.LogInvocationException(onceListeners[currentOnceCallIndex].Callback.Target ?? sender, Logger, exception, methodCallRepresentation);
             }
-            onceListeners.RemoveAt(i);
+            onceListeners.RemoveAt(currentOnceCallIndex);
         }
     }
 

Engine.Core/Helpers/FastListOrdered.cs

@@ -16,8 +16,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
     private readonly Func<TItem, TIndex> getIndexFunc = null!;
     private readonly IComparer<TIndex> sortBy = null!;
 
-    private int count = 0;
-    public int Count => count;
+    public int Count { get; private set; } = 0;
 
     public bool IsReadOnly { get; set; } = false;
 
@@ -35,10 +34,10 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
     private (TIndex TIndex, int i) GetAt(Index index)
     {
         int actualIndex = index.IsFromEnd
-                ? count - index.Value
+                ? Count - index.Value
                 : index.Value;
 
-        if (actualIndex < 0 || actualIndex >= count)
+        if (actualIndex < 0 || actualIndex >= Count)
             throw new IndexOutOfRangeException();
 
         int leftIndex = actualIndex;
@@ -75,7 +74,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
             items[key] = list = [];
 
         list.Add(item);
-        count++;
+        Count++;
     }
 
     public void Insert(int index, TItem item)
@@ -88,7 +87,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
             items[tIndex] = list = [];
 
         list.Insert(index, item);
-        count++;
+        Count++;
     }
 
     public bool Remove(TItem item)
@@ -103,7 +102,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
         if (!list.Remove(item))
             return false;
 
-        count--;
+        Count--;
         return true;
     }
 
@@ -114,7 +113,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
 
         (TIndex tIndex, int i) = GetAt(index);
         items[tIndex].RemoveAt(i);
-        count--;
+        Count--;
     }
 
     public void Clear()
@@ -125,7 +124,7 @@ public class FastListOrdered<TIndex, TItem> : IList<TItem>, IReadOnlyList<TItem>
         foreach ((TIndex index, FastList<TItem> list) in items)
             list.Clear();
 
-        count = 0;
+        Count = 0;
     }
 
     public bool Contains(TItem item)

Engine.Core/Math.cs

@@ -30,6 +30,16 @@ public static class Math
     /// </summary>
     public const float DegreeToRadian = Pi / 180f;
 
+    /// <inheritdoc cref="Invert{T}(T)" />
+    public static T OneOver<T>(T value) where T : INumber<T> => T.One / value;
+
+    /// <summary>
+    /// Gets 1 / value of given <see cref="T"/>.
+    /// </summary>
+    /// <param name="value">The value <see cref="T"/>.</param>
+    /// <returns>1 / value of given <see cref="T"/>.</returns>
+    public static T Invert<T>(T value) where T : INumber<T> => T.One / value;
+
     /// <summary>
     /// Gets one minus of given <see cref="T"/>.
     /// </summary>

Engine.Core/MathExtensions.cs

@@ -8,6 +8,12 @@ public static class MathExtensions
     /// <inheritdoc cref="Math.OneMinus{T}(T)" />
     public static T OneMinus<T>(this T value) where T : INumber<T> => Math.OneMinus(value);
 
+    /// <inheritdoc cref="Math.OneOver{T}(T)" />
+    public static T OneOver<T>(this T value) where T : INumber<T> => Math.OneOver(value);
+
+    /// <inheritdoc cref="Math.Invert{T}(T)" />
+    public static T Invert<T>(this T value) where T : INumber<T> => Math.OneMinus(value);
+
     /// <inheritdoc cref="Math.Add{T}(T, T)" />
     public static T Add<T>(this T left, T value) where T : INumber<T> => Math.Add(left, value);
 

Engine.Core/Primitives/Circle.cs

@@ -34,6 +34,16 @@ public readonly struct Circle(Vector2D center, float radius) : IEquatable<Circle
     /// </summary>
     public readonly float Diameter => 2f * Radius;
 
+    /// <summary>
+    /// Gets the area of the <see cref="Circle"/>.
+    /// </summary>
+    public readonly float Area => Math.Pi * RadiusSquared;
+
+    /// <summary>
+    /// Gets the geometric interia of the <see cref="Circle"/>.
+    /// </summary>
+    public readonly float GeometricInertia => .5f * RadiusSquared;
+
     /// <summary>
     /// A predefined unit <see cref="Circle"/> with a center at the origin and a radius of 1.
     /// </summary>

Engine.Core/Primitives/ColorRGB.cs

@@ -95,7 +95,11 @@ public readonly struct ColorRGB(byte r, byte g, byte b) : IEquatable<ColorRGB>
         int greenDiff = to.G - from.G;
         int blueDiff = to.B - from.B;
 
-        return from + new ColorRGB((byte)(redDiff * t), (byte)(greenDiff * t), (byte)(blueDiff * t));
+        return new(
+            (byte)(from.R + redDiff * t),
+            (byte)(from.G + greenDiff * t),
+            (byte)(from.B + blueDiff * t)
+        );
     }
 
     /// <summary>

Engine.Core/Primitives/ColorRGBA.cs

@@ -1,4 +1,5 @@
 using System;
+using Engine.Core.Debug;
 
 namespace Engine.Core;
 
@@ -125,7 +126,12 @@ public readonly struct ColorRGBA(byte r, byte g, byte b, byte a = 255) : IEquata
         int blueDiff = to.B - from.B;
         int alphaDiff = to.A - from.A;
 
-        return from + new ColorRGBA((byte)(redDiff * t), (byte)(greenDiff * t), (byte)(blueDiff * t), (byte)(alphaDiff * t));
+        return new(
+            (byte)(from.R + redDiff * t),
+            (byte)(from.G + greenDiff * t),
+            (byte)(from.B + blueDiff * t),
+            (byte)(from.A + alphaDiff * t)
+        );
     }
 
     /// <summary>

Engine.Core/Primitives/Matrix4x4.cs

@@ -436,4 +436,9 @@ public static class Matrix4x4Extensions
 
     /// <inheritdoc cref="Matrix4x4.ToRightHanded(Matrix4x4) />
     public static Matrix4x4 ToRightHanded(this Matrix4x4 matrix) => Matrix4x4.ToRightHanded(matrix);
+
+    /// <summary>
+    /// Multiplies two <see cref="Matrix4x4"/>'s.
+    /// </summary>
+    public static Matrix4x4 ApplyMatrix(this Matrix4x4 left, Matrix4x4 right) => left * right;
 }

Engine.Core/Primitives/Shape2D.cs

@@ -22,6 +22,31 @@ public class Shape2D(List<Vector2D> vertices) : IEnumerable<Vector2D>
 
     private readonly List<Vector2D> _vertices = vertices;
 
+    /// <summary>
+    /// Gets the area of the <see cref="Shape2D"/>.
+    /// </summary>
+    public float Area
+    {
+        get
+        {
+            float area = 0f;
+
+            for (int i = 0; i < _vertices.Count; i++)
+            {
+                Vector2D a = _vertices[i];
+                Vector2D b = _vertices[(i + 1) % _vertices.Count];
+                area += a.Cross(b);
+            }
+
+            return area.Abs() * .5f;
+        }
+    }
+
+    /// <summary>
+    /// Gets the geometric interia of the <see cref="Shape2D"/>.
+    /// </summary>
+    public float GeometricInertia => GetGeometricInertia(this, Vector2D.Zero);
+
     /// <summary>
     /// Gets the vertices of the <see cref="Shape2D"/>.
     /// </summary>
@@ -112,6 +137,40 @@ public class Shape2D(List<Vector2D> vertices) : IEnumerable<Vector2D>
         return new Triangle(p1, p2, p3);
     }
 
+    /// <summary>
+    /// Gets the geometric interia of the <see cref="Shape2D"/>.
+    /// </summary>
+    /// <param name="shape">The shape to get the geometrical interia of.</param>
+    /// <param name="centerOfMass">The point in space to calculate the geometrical interia from.</param>
+    /// <returns>The geometrical interia of the <see cref="Shape2D"/>.</returns>
+    public static float GetGeometricInertia(Shape2D shape, Vector2D centerOfMass)
+    {
+        float geometricInertia = 0f;
+
+        for (int i = 0; i < shape._vertices.Count; i++)
+        {
+            Vector2D p1 = centerOfMass.FromTo(shape._vertices[i]);
+            Vector2D p2 = centerOfMass.FromTo(shape._vertices[(i + 1) % shape._vertices.Count]);
+
+            float cross = p1.Cross(p2);
+            float dot = p1.Dot(p1) + p1.Dot(p2) + p2.Dot(p2);
+
+            geometricInertia += cross * dot;
+        }
+
+        return geometricInertia.Abs() / 12f;
+    }
+
+    /// <summary>
+    /// Gets the  interia of the <see cref="Shape2D"/>.
+    /// </summary>
+    /// <param name="shape">The shape to get the interia of.</param>
+    /// <param name="centerOfMass">The point in space to calculate the geometrical interia from.</param>
+    /// <param name="mass">Mass of the shape.</param>
+    /// <returns>The interia of the <see cref="Shape2D"/>.</returns>
+    public static float GetInertia(Shape2D shape, Vector2D centerOfMass, float mass)
+        => GetGeometricInertia(shape, centerOfMass) * mass;
+
     /// <summary>
     /// Triangulates the given convex <see cref="Shape2D"/>.
     /// </summary>
@@ -297,6 +356,12 @@ public static class Shape2DExtensions
     /// <inheritdoc cref="Shape2D.GetSuperTriangle(Shape2D)" />
     public static Triangle ToSuperTriangle(this Shape2D shape) => Shape2D.GetSuperTriangle(shape);
 
+    /// <inheritdoc cref="Shape2D.GetGeometricInertia(Shape2D, Vector2D)" />
+    public static float GetGeometricInertia(this Shape2D shape, Vector2D centerOfMass) => Shape2D.GetGeometricInertia(shape, centerOfMass);
+
+    /// <inheritdoc cref="Shape2D.GetInertia(Shape2D, Vector2D, float)" />
+    public static float GetInertia(this Shape2D shape, Vector2D centerOfMass, float mass) => Shape2D.GetInertia(shape, centerOfMass, mass);
+
     /// <inheritdoc cref="Shape2D.TriangulateConvex(Shape2D, IList{Triangle})" />
     public static void ToTrianglesConvex(this Shape2D shape, IList<Triangle> triangles) => Shape2D.TriangulateConvex(shape, triangles);
 

Engine.Core/Serialization/ISerializer.cs

@@ -4,15 +4,15 @@ namespace Engine.Core.Serialization;
 
 public interface ISerializer
 {
-    object Deserialize(string configuration);
-    object Deserialize(string configuration, Type type);
-    T Deserialize<T>(string configuration);
+    object Deserialize(string content);
+    object Deserialize(string content, Type type);
+    T Deserialize<T>(string content);
 
     string Serialize(object instance);
 
-    ProgressiveTask<object> DeserializeAsync(string configuration);
-    ProgressiveTask<object> DeserializeAsync(string configuration, Type type);
-    ProgressiveTask<T> DeserializeAsync<T>(string configuration);
+    ProgressiveTask<object> DeserializeAsync(string content);
+    ProgressiveTask<object> DeserializeAsync(string content, Type type);
+    ProgressiveTask<T> DeserializeAsync<T>(string content);
 
     ProgressiveTask<string> SerializeAsync(object instance);
 }

Engine.Core/Systems/Abstract/ICoroutineManager.cs

@@ -0,0 +1,9 @@
+using System.Collections;
+
+namespace Engine.Core;
+
+public interface ICoroutineManager
+{
+    IEnumerator StartCoroutine(IEnumerator enumerator);
+    void StopCoroutine(IEnumerator enumerator);
+}

Engine.Core/Systems/CoroutineManager.cs

@@ -1,6 +1,8 @@
 using System.Collections;
 using System.Collections.Generic;
 
+using Engine.Core.Debug;
+
 namespace Engine.Core;
 
 public class CoroutineManager : Behaviour, IUpdate
@@ -22,11 +24,21 @@ public class CoroutineManager : Behaviour, IUpdate
     {
         for (int i = enumerators.Count - 1; i >= 0; i--)
         {
-            if (enumerators[i].Current is ICoroutineYield coroutineYield && coroutineYield.Yield())
-                continue;
+            try
+            {
+                if (enumerators[i].Current is ICoroutineYield coroutineYield && coroutineYield.Yield())
+                    continue;
 
-            if (!enumerators[i].MoveNext())
+                if (!enumerators[i].MoveNext())
+                    enumerators.RemoveAt(i);
+            }
+            catch (System.Exception exception)
+            {
+                ILogger.Shared.LogError(this, $"Coroutine failed, removing from execution.");
+                ILogger.Shared.LogException(this, exception);
+                ILogger.Shared.LogTrace(exception.StackTrace);
                 enumerators.RemoveAt(i);
+            }
         }
     }
 

Engine.Core/Systems/NestedCoroutineManager.cs

@@ -0,0 +1,92 @@
+using System.Collections;
+using System.Collections.Generic;
+
+using Engine.Core.Debug;
+
+namespace Engine.Core;
+
+public class NestedCoroutineManager : Behaviour, IUpdate, ICoroutineManager
+{
+    private readonly List<CoroutineStack> stacks = [];
+    private readonly Pool<CoroutineStack> pool = new(() => new());
+
+    public IEnumerator StartCoroutine(IEnumerator enumerator)
+    {
+        CoroutineStack stack = pool.Get();
+        stack.EntryPoint = enumerator;
+        stack.Stack.Push(enumerator);
+
+        stacks.Add(stack);
+
+        return enumerator;
+    }
+
+    public void StopCoroutine(IEnumerator enumerator)
+    {
+        for (int i = 0; i < stacks.Count; i++)
+            if (stacks[i].EntryPoint == enumerator)
+            {
+                RemoveCoroutineAt(i);
+                return;
+            }
+    }
+
+    private void RemoveCoroutineAt(int i)
+    {
+        stacks[i].Reset();
+        stacks.RemoveAt(i);
+    }
+
+    void IUpdate.Update()
+    {
+        for (int i = stacks.Count - 1; i >= 0; i--)
+        {
+            Stack<IEnumerator> stack = stacks[i].Stack;
+
+            if (stack.Count == 0)
+            {
+                RemoveCoroutineAt(i);
+                continue;
+            }
+
+            try
+            {
+                IEnumerator top = stack.Peek();
+
+                if (top.Current is ICoroutineYield coroutineYield && coroutineYield.Yield())
+                    continue;
+
+                if (top.Current is IEnumerator nested)
+                {
+                    stack.Push(nested);
+                    continue;
+                }
+
+                if (!top.MoveNext())
+                {
+                    stack.Pop();
+                    if (stack.Count != 0)
+                        stack.Peek().MoveNext();
+                    continue;
+                }
+            }
+            catch (System.Exception exception)
+            {
+                ILogger.Shared.LogError(this, $"Coroutine failed, removing from execution.");
+                ILogger.Shared.LogException(this, exception);
+                ILogger.Shared.LogTrace(exception.StackTrace);
+                RemoveCoroutineAt(i);
+            }
+        }
+    }
+
+    private class CoroutineStack
+    {
+        public IEnumerator EntryPoint = null!;
+        public Stack<IEnumerator> Stack = new();
+
+        public void Reset() { EntryPoint = null!; Stack.Clear(); }
+    }
+
+    public NestedCoroutineManager() => Priority = int.MinValue;
+}

Engine.Core/Systems/UpdateManager.cs

@@ -44,6 +44,17 @@ public class UpdateManager : Behaviour, IEnterUniverse, IExitUniverse
         universe.OnPostUpdate.RemoveListener(OnPostUpdate);
     }
 
+    /// <summary>
+    /// Call the <see cref="IFirstFrameUpdate"/> early if it's in queue to be called by this the <see cref="UpdateManager"/>. 
+    /// It will not be called in the next natural cycle.
+    /// </summary>
+    /// <param name="instance">The instance that will be called now rather than later.</param>
+    public void CallFirstActiveFrameImmediately(IFirstFrameUpdate instance)
+    {
+        if (toCallFirstFrameUpdates.Remove(instance))
+            instance.FirstActiveFrame();
+    }
+
     private void OnFirstUpdate(IUniverse sender, IUniverse.UpdateArguments args)
     {
         for (int i = toCallFirstFrameUpdates.Count - 1; i >= 0; i--)

Engine.Core/Systems/Yields/WaitForTaskYield.cs

@@ -0,0 +1,35 @@
+using System.Threading.Tasks;
+
+using static Engine.Core.WaitForTaskYield;
+
+namespace Engine.Core;
+
+public class WaitForTaskYield(Task task, TaskCompletionStatus completionStatus = TaskCompletionStatus.Any) : ICoroutineYield
+{
+    public bool Yield()
+    {
+        switch (completionStatus)
+        {
+            case TaskCompletionStatus.Success:
+                if (task.IsCanceled)
+                    throw new("Task has been canceled.");
+                if (task.IsFaulted)
+                    throw task.Exception ?? new("Task has faulted.");
+                return !task.IsCompletedSuccessfully;
+
+            case TaskCompletionStatus.Fail:
+                if (task.IsCompletedSuccessfully)
+                    throw new("Task was completed successfully.");
+                return !task.IsFaulted;
+        }
+
+        return !task.IsCompleted;
+    }
+
+    public enum TaskCompletionStatus
+    {
+        Any,
+        Success,
+        Fail
+    }
+}

Engine.Core/Systems/Yields/WaitForTimeYield.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace Engine.Core;
+
+public class WaitForTimeYield(float seconds = 0f, float milliseconds = 0f, float minutes = 0f, float hours = 0f) : ICoroutineYield
+{
+    private readonly DateTime triggerTime = DateTime.UtcNow
+        .AddHours(hours)
+        .AddMinutes(minutes)
+        .AddSeconds(seconds)
+        .AddMilliseconds(milliseconds);
+
+    public bool Yield() => DateTime.UtcNow < triggerTime;
+}

Engine.Core/Systems/Yields/WaitUntilYield.cs

@@ -0,0 +1,10 @@
+using System;
+
+namespace Engine.Core;
+
+public class WaitUntilYield(Func<bool> condition) : ICoroutineYield
+{
+    private readonly Func<bool> condition = condition;
+
+    public bool Yield() => !condition.Invoke();
+}

Engine.Core/Systems/Yields/WaitWhileYield.cs

@@ -2,7 +2,7 @@ using System;
 
 namespace Engine.Core;
 
-public class CoroutineYield(Func<bool> condition) : ICoroutineYield
+public class WaitWhileYield(Func<bool> condition) : ICoroutineYield
 {
     private readonly Func<bool> condition = condition;
 

Engine.Core/Systems/Yields/YieldExtensions.cs

@@ -0,0 +1,10 @@
+using System.Threading.Tasks;
+
+using static Engine.Core.WaitForTaskYield;
+
+namespace Engine.Core;
+
+public static class YieldExtensions
+{
+    public static WaitForTaskYield ToYield(this Task task, TaskCompletionStatus completionStatus = TaskCompletionStatus.Any) => new(task, completionStatus);
+}

Engine.Integration/Engine.Integration.LiteNetLib/LiteNetLibCommunicatorBase.cs

@@ -178,6 +178,7 @@ public abstract class LiteNetLibCommunicatorBase : Behaviour, IEnterUniverse, IE
         netPacketProcessor.RegisterNestedType(Vector3DNetPacker.Write, Vector3DNetPacker.Read);
         netPacketProcessor.RegisterNestedType(Vector3DIntNetPacker.Write, Vector3DIntNetPacker.Read);
         netPacketProcessor.RegisterNestedType(Vector4DNetPacker.Write, Vector4DNetPacker.Read);
+        netPacketProcessor.RegisterNestedType(Matrix4x4NetPacker.Write, Matrix4x4NetPacker.Read);
     }
 
     public INetworkCommunicator SubscribeToPackets<T>(Event<IConnection, T>.EventHandler callback)

Engine.Integration/Engine.Integration.LiteNetLib/LiteNetLibServer.cs

@@ -6,7 +6,7 @@ using Engine.Core.Debug;
 
 namespace Engine.Systems.Network;
 
-public class LiteNetLibServer : LiteNetLibCommunicatorBase, INetworkCommunicatorServer
+public class LiteNetLibServer : LiteNetLibCommunicatorBase, INetworkCommunicatorServer, IPostUpdate
 {
     public string Password { get; private set; } = string.Empty;
     public int MaxConnectionCount { get; private set; } = 2;
@@ -104,17 +104,8 @@ public class LiteNetLibServer : LiteNetLibCommunicatorBase, INetworkCommunicator
         }
     }
 
-    private void PollEvents(IUniverse sender, IUniverse.UpdateArguments args) => Manager.PollEvents();
-
-    public override void EnterUniverse(IUniverse universe)
+    public void PostUpdate()
     {
-        base.EnterUniverse(universe);
-        universe.OnPostUpdate.AddListener(PollEvents);
-    }
-
-    public override void ExitUniverse(IUniverse universe)
-    {
-        base.ExitUniverse(universe);
-        universe.OnPostUpdate.RemoveListener(PollEvents);
+        Manager.PollEvents();
     }
 }

Engine.Integration/Engine.Integration.LiteNetLib/Packers/Matrix4x4NetPacker.cs

@@ -0,0 +1,61 @@
+using LiteNetLib.Utils;
+
+using Engine.Core;
+
+namespace Engine.Systems.Network.Packers;
+
+internal static class Matrix4x4NetPacker
+{
+    internal static void Write(NetDataWriter writer, Matrix4x4 data)
+    {
+        writer.Put(data.M11);
+        writer.Put(data.M12);
+        writer.Put(data.M13);
+        writer.Put(data.M14);
+
+        writer.Put(data.M21);
+        writer.Put(data.M22);
+        writer.Put(data.M23);
+        writer.Put(data.M24);
+
+        writer.Put(data.M31);
+        writer.Put(data.M32);
+        writer.Put(data.M33);
+        writer.Put(data.M34);
+
+        writer.Put(data.M41);
+        writer.Put(data.M42);
+        writer.Put(data.M43);
+        writer.Put(data.M44);
+    }
+
+    internal static Matrix4x4 Read(NetDataReader reader)
+    {
+        float m11 = reader.GetFloat();
+        float m12 = reader.GetFloat();
+        float m13 = reader.GetFloat();
+        float m14 = reader.GetFloat();
+
+        float m21 = reader.GetFloat();
+        float m22 = reader.GetFloat();
+        float m23 = reader.GetFloat();
+        float m24 = reader.GetFloat();
+
+        float m31 = reader.GetFloat();
+        float m32 = reader.GetFloat();
+        float m33 = reader.GetFloat();
+        float m34 = reader.GetFloat();
+
+        float m41 = reader.GetFloat();
+        float m42 = reader.GetFloat();
+        float m43 = reader.GetFloat();
+        float m44 = reader.GetFloat();
+
+        return new Matrix4x4(
+            m11, m12, m13, m14,
+            m21, m22, m23, m24,
+            m31, m32, m33, m34,
+            m41, m42, m43, m44
+        );
+    }
+}

Engine.Integration/Engine.Integration.MonoGame/Behaviours/MonoGameCamera2D.cs

@@ -1,5 +1,4 @@
 using Microsoft.Xna.Framework;
-using Microsoft.Xna.Framework.Graphics;
 
 using Engine.Core;
 
@@ -41,7 +40,7 @@ public class MonoGameCamera2D : Behaviour, ICamera2D, IFirstFrameUpdate, ILastFr
         }
     } = Matrix4x4.Identity;
 
-    public Viewport Viewport
+    public Vector2D Viewport
     {
         get;
         set
@@ -72,8 +71,8 @@ public class MonoGameCamera2D : Behaviour, ICamera2D, IFirstFrameUpdate, ILastFr
     // TODO This causes delay since OnPreDraw calls assuming this is called in in Update 
     public Vector2D ScreenToWorldPosition(Vector2D screenPosition)
     {
-        float x = 2f * screenPosition.X / Viewport.Width - 1f;
-        float y = 1f - 2f * screenPosition.Y / Viewport.Height;
+        float x = 2f * screenPosition.X / Viewport.X - 1f;
+        float y = 1f - 2f * screenPosition.Y / Viewport.Y;
         Vector4D normalizedCoordinates = new(x, y, 0f, 1f);
 
         Matrix4x4 invertedViewProjectionMatrix = (ProjectionMatrix * ViewMatrix).Inverse;
@@ -96,8 +95,8 @@ public class MonoGameCamera2D : Behaviour, ICamera2D, IFirstFrameUpdate, ILastFr
         if (clip.W != 0f)
             clip /= clip.W;
 
-        float screenX = (clip.X + 1f) * .5f * Viewport.Width;
-        float screenY = (1f - clip.Y) * .5f * Viewport.Height;
+        float screenX = (clip.X + 1f) * .5f * Viewport.X;
+        float screenY = (1f - clip.Y) * .5f * Viewport.Y;
 
         return new(screenX, screenY);
     }
@@ -106,17 +105,17 @@ public class MonoGameCamera2D : Behaviour, ICamera2D, IFirstFrameUpdate, ILastFr
     public void FirstActiveFrame()
     {
         Graphics = BehaviourController.UniverseObject.Universe.FindRequiredBehaviour<MonoGameWindowContainer>().Window.Graphics;
-        Viewport = Graphics.GraphicsDevice.Viewport;
+        Viewport = new(Graphics.GraphicsDevice.Viewport.Width, Graphics.GraphicsDevice.Viewport.Height);
         Transform = BehaviourController.GetRequiredBehaviour<ITransform2D>();
     }
 
     public void PreDraw()
     {
-        ProjectionMatrix = Matrix4x4.CreateOrthographicViewCentered(Viewport.Width, Viewport.Height);
-        ViewMatrix =
-            Matrix4x4.CreateTranslation(new Vector3D(-Transform.Position.X, -Transform.Position.Y, 0f))
-                .ApplyRotationZ(Transform.Rotation * Math.DegreeToRadian)
-                .ApplyScale(Transform.Scale.X.Max(Transform.Scale.Y))
-                .ApplyScale(Zoom);
+        ProjectionMatrix = Matrix4x4.CreateOrthographicViewCentered(Viewport.X, Viewport.Y);
+        ViewMatrix = Matrix4x4.Identity
+            .ApplyTranslation(new Vector3D(-Transform.Position.X, -Transform.Position.Y, 0f))
+            .ApplyRotationZ(Transform.Rotation * Math.DegreeToRadian)
+            .ApplyScale(Transform.Scale.X.Max(Transform.Scale.Y))
+            .ApplyScale(Zoom);
     }
 }

Engine.Integration/Engine.Integration.MonoGame/Behaviours/MonoGameCamera3D.cs

@@ -49,7 +49,7 @@ public class MonoGameCamera3D : Behaviour, ICamera3D, IFirstFrameUpdate, ILastFr
         }
     } = Matrix4x4.Identity;
 
-    public Viewport Viewport
+    public Vector2D Viewport
     {
         get;
         set
@@ -57,7 +57,7 @@ public class MonoGameCamera3D : Behaviour, ICamera3D, IFirstFrameUpdate, ILastFr
             if (field.Equals(value))
                 return;
 
-            Viewport previousViewport = field;
+            Vector2D previousViewport = field;
             field = value;
             SetForRecalculation();
             OnViewportChanged.Invoke(this, new(previousViewport));
@@ -114,21 +114,21 @@ public class MonoGameCamera3D : Behaviour, ICamera3D, IFirstFrameUpdate, ILastFr
         Matrix projection = ProjectionMatrix.ToXnaMatrix();
         Matrix view = ViewMatrix.ToXnaMatrix();
 
-        Vector3 worldNear = Viewport.Unproject(nearPoint, projection, view, Matrix.Identity);
-        Vector3 worldFar = Viewport.Unproject(farPoint, projection, view, Matrix.Identity);
+        Vector3 worldNear = Graphics.GraphicsDevice.Viewport.Unproject(nearPoint, projection, view, Matrix.Identity);
+        Vector3 worldFar = Graphics.GraphicsDevice.Viewport.Unproject(farPoint, projection, view, Matrix.Identity);
 
         Vector3 direction = Vector3.Normalize(worldFar - worldNear);
         return new(worldNear.ToVector3D(), direction.ToVector3D());
     }
 
-    public Vector2D WorldToScreenPosition(Vector3D worldPosition) => Viewport.Project(worldPosition.ToVector3(), ProjectionMatrix.ToXnaMatrix(), ViewMatrix.ToXnaMatrix(), Matrix.Identity).ToVector3D();
+    public Vector2D WorldToScreenPosition(Vector3D worldPosition) => Graphics.GraphicsDevice.Viewport.Project(worldPosition.ToVector3(), ProjectionMatrix.ToXnaMatrix(), ViewMatrix.ToXnaMatrix(), Matrix.Identity).ToVector3D();
 
     public void LastActiveFrame() => Transform.OnTransformUpdated.RemoveListener(SetDirtyOnTransformUpdate);
     public void FirstActiveFrame()
     {
         Transform = BehaviourController.GetRequiredBehaviour<ITransform3D>();
         Graphics = BehaviourController.UniverseObject.Universe.FindRequiredBehaviour<MonoGameWindowContainer>().Window.Graphics;
-        Viewport = Graphics.GraphicsDevice.Viewport;
+        Viewport = new(Graphics.GraphicsDevice.Viewport.Width, Graphics.GraphicsDevice.Viewport.Height);
 
         Transform.OnTransformUpdated.AddListener(SetDirtyOnTransformUpdate);
     }
@@ -167,7 +167,7 @@ public class MonoGameCamera3D : Behaviour, ICamera3D, IFirstFrameUpdate, ILastFr
     private void CalculateProjection()
     {
         float yScale = 1f / (float)Math.Tan(fieldOfView / 2f);
-        float xScale = yScale / Viewport.AspectRatio;
+        float xScale = yScale / (Viewport.X / Viewport.Y);
 
         ProjectionMatrix = new Matrix4x4(
             xScale, 0, 0, 0,
@@ -179,5 +179,5 @@ public class MonoGameCamera3D : Behaviour, ICamera3D, IFirstFrameUpdate, ILastFr
 
     public readonly record struct ViewChangedArguments(Matrix4x4 PreviousView);
     public readonly record struct ProjectionChangedArguments(Matrix4x4 PreviousProjection);
-    public readonly record struct ViewportChangedArguments(Viewport PreviousViewport);
+    public readonly record struct ViewportChangedArguments(Vector2D PreviousViewport);
 }

Engine.Integration/Engine.Integration.MonoGame/Behaviours/SpriteBatcher.cs

@@ -1,5 +1,7 @@
 using System.Collections.Generic;
 
+using Microsoft.Xna.Framework.Graphics;
+
 using Engine.Core;
 
 namespace Engine.Integration.MonoGame;
@@ -12,6 +14,7 @@ public class SpriteBatcher : Behaviour, IFirstFrameUpdate, IDraw
     private ISpriteBatch spriteBatch = null!;
     private MonoGameCamera2D camera2D = null!;
 
+    private readonly RasterizerState rasterizerState = new() { CullMode = CullMode.CullClockwiseFace };
     private readonly ActiveBehaviourCollectorOrdered<int, IDrawableSprite> drawableSprites = new(GetPriority(), SortByPriority());
 
     public void FirstActiveFrame()
@@ -26,7 +29,13 @@ public class SpriteBatcher : Behaviour, IFirstFrameUpdate, IDraw
 
     public void Draw()
     {
-        spriteBatch.Begin(transformMatrix: camera2D.ViewMatrix.ToXnaMatrix());
+        Matrix4x4 transformMatrix = Matrix4x4.Identity
+            .ApplyTranslation(new Vector2D(camera2D.Viewport.X, camera2D.Viewport.Y) * .5f)
+            .ApplyScale(new Vector3D(1f, -1f, 1f))
+            .ApplyMatrix(camera2D.ViewMatrix)
+            .Transposed;
+
+        spriteBatch.Begin(transformMatrix: transformMatrix.ToXnaMatrix(), rasterizerState: rasterizerState);
         for (int i = 0; i < drawableSprites.Count; i++)
             drawableSprites[i].Draw(spriteBatch);
         spriteBatch.End();

Engine.Integration/Engine.Integration.MonoGame/MonoGameTriangleBatch.cs

@@ -19,8 +19,11 @@ public class MonoGameTriangleBatch : Behaviour, ITriangleBatch, IFirstFrameUpdat
     private BasicEffect basicEffect = null!;
     private readonly RasterizerState rasterizerState = new() { CullMode = CullMode.None };
 
+    private ICamera camera = null!;
+
     public void FirstActiveFrame()
     {
+        camera = Universe.FindRequiredBehaviour<ICamera>();
         GraphicsDevice graphicsDevice = Universe.FindRequiredBehaviour<MonoGameWindowContainer>().Window.GraphicsDevice;
         this.graphicsDevice = graphicsDevice;
         basicEffect = new(graphicsDevice);
@@ -36,7 +39,7 @@ public class MonoGameTriangleBatch : Behaviour, ITriangleBatch, IFirstFrameUpdat
         Vector2 A = triangle.A.ToVector2();
         Vector2 B = triangle.B.ToVector2();
         Vector2 C = triangle.C.ToVector2();
-        Color color = colorRGBA.ToColor();
+        Color color = colorRGBA.ToPreMultipliedColor();
 
         vertices[verticesIndex++] = new(new(A.X, A.Y, 0f), color);
         vertices[verticesIndex++] = new(new(B.X, B.Y, 0f), color);
@@ -45,10 +48,8 @@ public class MonoGameTriangleBatch : Behaviour, ITriangleBatch, IFirstFrameUpdat
 
     public void Begin(Matrix4x4? view = null, Matrix4x4? projection = null)
     {
-        Viewport viewport = graphicsDevice.Viewport;
-
-        this.view = (view ?? Matrix4x4.Identity).Transposed.ToXnaMatrix();
-        this.projection = (projection ?? Matrix4x4.CreateOrthographicViewCentered(viewport.Width, viewport.Height)).Transposed.ToXnaMatrix();
+        this.view = (view ?? camera.ViewMatrix).Transposed.ToXnaMatrix();
+        this.projection = (projection ?? camera.ProjectionMatrix).Transposed.ToXnaMatrix();
     }
 
     public void End() => Flush();
@@ -59,6 +60,8 @@ public class MonoGameTriangleBatch : Behaviour, ITriangleBatch, IFirstFrameUpdat
             return;
 
         graphicsDevice.RasterizerState = rasterizerState;
+        graphicsDevice.BlendState = BlendState.AlphaBlend;
+
         basicEffect.Projection = projection;
         basicEffect.View = view;
         vertexBuffer.SetData(vertices);
@@ -66,8 +69,10 @@ public class MonoGameTriangleBatch : Behaviour, ITriangleBatch, IFirstFrameUpdat
         graphicsDevice.SetVertexBuffer(vertexBuffer);
 
         foreach (EffectPass pass in basicEffect.CurrentTechnique.Passes)
+        {
             pass.Apply();
-        graphicsDevice.DrawPrimitives(PrimitiveType.TriangleList, 0, verticesIndex / 3);
+            graphicsDevice.DrawPrimitives(PrimitiveType.TriangleList, 0, verticesIndex / 3);
+        }
 
         verticesIndex = 0;
     }

Engine.Integration/Engine.Integration.Yaml/Converters/BehaviourControllerConverter.cs

@@ -11,7 +11,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class BehaviourControllerConverter : EngineTypeYamlSerializerBase<IBehaviourController>
+public class BehaviourControllerConverter : EngineTypeYamlConverterBase<IBehaviourController>
 {
     private const string BEHAVIOURS_SCALAR_NAME = "Behaviours";
 

Engine.Integration/Engine.Integration.Yaml/Converters/BehaviourConverter.cs

@@ -9,7 +9,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class BehaviourConverter : EngineTypeYamlSerializerBase<IBehaviour>
+public class BehaviourConverter : EngineTypeYamlConverterBase<IBehaviour>
 {
     public override IBehaviour? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/EngineTypeYamlConverterBase.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public abstract class EngineTypeYamlSerializerBase<T> : IEngineTypeYamlConverter
+public abstract class EngineTypeYamlConverterBase<T> : IEngineTypeYamlConverter
 {
     protected const string SERIALIZED_SCALAR_NAME = "Properties";
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/AABB2DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class AABB2DConverter : EngineTypeYamlSerializerBase<AABB2D>
+public class AABB2DConverter : EngineTypeYamlConverterBase<AABB2D>
 {
     public override AABB2D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/AABB3DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class AABB3DConverter : EngineTypeYamlSerializerBase<AABB3D>
+public class AABB3DConverter : EngineTypeYamlConverterBase<AABB3D>
 {
     public override AABB3D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/CircleConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class CircleConverter : EngineTypeYamlSerializerBase<Circle>
+public class CircleConverter : EngineTypeYamlConverterBase<Circle>
 {
     public override Circle Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/ColorHSVAConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class ColorHSVAConverter : EngineTypeYamlSerializerBase<ColorHSVA>
+public class ColorHSVAConverter : EngineTypeYamlConverterBase<ColorHSVA>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(ColorHSVA).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/ColorHSVConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class ColorHSVConverter : EngineTypeYamlSerializerBase<ColorHSV>
+public class ColorHSVConverter : EngineTypeYamlConverterBase<ColorHSV>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(ColorHSV).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/ColorRGBAConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class ColorRGBAConverter : EngineTypeYamlSerializerBase<ColorRGBA>
+public class ColorRGBAConverter : EngineTypeYamlConverterBase<ColorRGBA>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(ColorRGBA).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/ColorRGBConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class ColorRGBConverter : EngineTypeYamlSerializerBase<ColorRGB>
+public class ColorRGBConverter : EngineTypeYamlConverterBase<ColorRGB>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(ColorRGB).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Line2DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Line2DConverter : EngineTypeYamlSerializerBase<Line2D>
+public class Line2DConverter : EngineTypeYamlConverterBase<Line2D>
 {
     public override Line2D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Line2DEquationConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Line2DEquationConverter : EngineTypeYamlSerializerBase<Line2DEquation>
+public class Line2DEquationConverter : EngineTypeYamlConverterBase<Line2DEquation>
 {
     public override Line2DEquation Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Line3DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Line3DConverter : EngineTypeYamlSerializerBase<Line3D>
+public class Line3DConverter : EngineTypeYamlConverterBase<Line3D>
 {
     public override Line3D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Matrix4x4Converter.cs

@@ -0,0 +1,33 @@
+using System;
+
+using Engine.Core;
+
+using YamlDotNet.Core;
+using YamlDotNet.Core.Events;
+using YamlDotNet.Serialization;
+
+namespace Engine.Serializers.Yaml;
+
+public class Matrix4x4Converter : EngineTypeYamlConverterBase<Matrix4x4>
+{
+    private static readonly int SUBSTRING_START_LENGTH = nameof(Matrix4x4).Length + 1;
+
+    public override Matrix4x4 Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
+    {
+        string value = parser.Consume<Scalar>().Value;
+        string insideParenthesis = value[SUBSTRING_START_LENGTH..^1];
+        string[] values = insideParenthesis.Split(", ");
+        return new Matrix4x4(
+            float.Parse(values[0]), float.Parse(values[1]), float.Parse(values[2]), float.Parse(values[3]),
+            float.Parse(values[4]), float.Parse(values[5]), float.Parse(values[6]), float.Parse(values[7]),
+            float.Parse(values[8]), float.Parse(values[9]), float.Parse(values[10]), float.Parse(values[11]),
+            float.Parse(values[12]), float.Parse(values[13]), float.Parse(values[14]), float.Parse(values[15])
+        );
+    }
+
+    public override void WriteYaml(IEmitter emitter, object? value, Type type, ObjectSerializer serializer)
+    {
+        Matrix4x4 m = (Matrix4x4)value!;
+        emitter.Emit(new Scalar($"{nameof(Matrix4x4)}({m.M11}, {m.M12}, {m.M13}, {m.M14},{m.M21}, {m.M22}, {m.M23}, {m.M24},{m.M31}, {m.M32}, {m.M33}, {m.M34},{m.M41}, {m.M42}, {m.M43}, {m.M44})"));
+    }
+}

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Projection1DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Projection1DConverter : EngineTypeYamlSerializerBase<Projection1D>
+public class Projection1DConverter : EngineTypeYamlConverterBase<Projection1D>
 {
     public override Projection1D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/QuaternionConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class QuaternionConverter : EngineTypeYamlSerializerBase<Quaternion>
+public class QuaternionConverter : EngineTypeYamlConverterBase<Quaternion>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Quaternion).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Ray2DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Ray2DConverter : EngineTypeYamlSerializerBase<Ray2D>
+public class Ray2DConverter : EngineTypeYamlConverterBase<Ray2D>
 {
     public override Ray2D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Ray3DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Ray3DConverter : EngineTypeYamlSerializerBase<Ray3D>
+public class Ray3DConverter : EngineTypeYamlConverterBase<Ray3D>
 {
     public override Ray3D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Shape2DConverter.cs

@@ -9,7 +9,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Shape2DConverter : EngineTypeYamlSerializerBase<Shape2D>
+public class Shape2DConverter : EngineTypeYamlConverterBase<Shape2D>
 {
     public override Shape2D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Sphere3DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Sphere3DConverter : EngineTypeYamlSerializerBase<Sphere3D>
+public class Sphere3DConverter : EngineTypeYamlConverterBase<Sphere3D>
 {
     public override Sphere3D Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/TriangleConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class TriangleConverter : EngineTypeYamlSerializerBase<Triangle>
+public class TriangleConverter : EngineTypeYamlConverterBase<Triangle>
 {
     public override Triangle Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Vector2DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Vector2DConverter : EngineTypeYamlSerializerBase<Vector2D>
+public class Vector2DConverter : EngineTypeYamlConverterBase<Vector2D>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Vector2D).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Vector2DIntConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Vector2DIntConverter : EngineTypeYamlSerializerBase<Vector2DInt>
+public class Vector2DIntConverter : EngineTypeYamlConverterBase<Vector2DInt>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Vector2DInt).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Vector3DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Vector3DConverter : EngineTypeYamlSerializerBase<Vector3D>
+public class Vector3DConverter : EngineTypeYamlConverterBase<Vector3D>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Vector3D).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Vector3DIntConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Vector3DIntConverter : EngineTypeYamlSerializerBase<Vector3DInt>
+public class Vector3DIntConverter : EngineTypeYamlConverterBase<Vector3DInt>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Vector3DInt).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/Primitives/Vector4DConverter.cs

@@ -8,7 +8,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class Vector4DConverter : EngineTypeYamlSerializerBase<Vector4D>
+public class Vector4DConverter : EngineTypeYamlConverterBase<Vector4D>
 {
     private static readonly int SUBSTRING_START_LENGTH = nameof(Vector4D).Length + 1;
 

Engine.Integration/Engine.Integration.Yaml/Converters/SerializedClassConverter.cs

@@ -12,7 +12,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class SerializedClassConverter : EngineTypeYamlSerializerBase<SerializedClass>
+public class SerializedClassConverter : EngineTypeYamlConverterBase<SerializedClass>
 {
     public override SerializedClass? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {
@@ -37,17 +37,25 @@ public class SerializedClassConverter : EngineTypeYamlSerializerBase<SerializedC
             }
         }
 
+        foreach ((string key, object @object) in publicDictionary)
+            if (@object is IDictionary<object, object> dictionary && dictionary.TryGetValue(nameof(TypeContainer.Type), out object? typeField) && dictionary.TryGetValue(nameof(TypeContainer.Value), out object? valueField))
+                publicDictionary[key] = new TypeContainer() { Type = typeField!.ToString()!, Value = valueField };
+
+        foreach ((string key, object @object) in privateDictionary)
+            if (@object is IDictionary<object, object> dictionary && dictionary.TryGetValue(nameof(TypeContainer.Type), out object? typeField) && dictionary.TryGetValue(nameof(TypeContainer.Value), out object? valueField))
+                privateDictionary[key] = new TypeContainer() { Type = typeField!.ToString()!, Value = valueField };
+
         Type classType = TypeFactory.GetType(serializedClass.Type);
 
         foreach ((string key, object @object) in publicDictionary)
             if (@object is TypeContainer typeContainer)
-                serializedClass.Public.Add(key, Serializer.InternalDeserialize(typeContainer.Value!.ToString()!, TypeFactory.GetType(typeContainer.Type)));
+                serializedClass.Public.Add(key, Serializer.InternalDeserialize(Serializer.Serialize(typeContainer.Value!), TypeFactory.GetType(typeContainer.Type)));
             else
                 serializedClass.Public.Add(key, Serializer.InternalDeserialize(@object.ToString()!, (classType.GetProperty(key, System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance)?.PropertyType ?? classType.GetField(key, System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance)?.FieldType)!));
 
         foreach ((string key, object @object) in privateDictionary)
             if (@object is TypeContainer typeContainer)
-                serializedClass.Private.Add(key, Serializer.InternalDeserialize(typeContainer.Value!.ToString()!, TypeFactory.GetType(typeContainer.Type)));
+                serializedClass.Private.Add(key, Serializer.InternalDeserialize(Serializer.Serialize(typeContainer.Value!), TypeFactory.GetType(typeContainer.Type)));
             else
                 serializedClass.Private.Add(key, Serializer.InternalDeserialize(@object.ToString()!, (classType.GetProperty(key, System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Default)?.PropertyType ?? classType.GetField(key, System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Default)?.FieldType)!));
 
@@ -65,14 +73,14 @@ public class SerializedClassConverter : EngineTypeYamlSerializerBase<SerializedC
         Dictionary<string, object> publics = [];
         Dictionary<string, object> privates = [];
 
-        foreach ((string key, object? @object) in serializedClass.Public.Where(v => !v.GetType().HasAttribute<IgnoreSerializationAttribute>()))
-            if (@object?.GetType().IsClass == false)
+        foreach ((string key, object? @object) in serializedClass.Public)
+            if (@object?.GetType().IsClass == false || @object is string)
                 publics.Add(key, @object!);
             else
                 publics.Add(key, new TypeContainer(@object));
 
-        foreach ((string key, object? @object) in serializedClass.Private.Where(v => !v.GetType().HasAttribute<IgnoreSerializationAttribute>()))
-            if (@object?.GetType().IsClass == false)
+        foreach ((string key, object? @object) in serializedClass.Private)
+            if (@object?.GetType().IsClass == false || @object is string)
                 privates.Add(key, @object!);
             else
                 privates.Add(key, new TypeContainer(@object));

Engine.Integration/Engine.Integration.Yaml/Converters/StateEnableConverter.cs

@@ -9,7 +9,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class StateEnableConverter : EngineTypeYamlSerializerBase<IStateEnable>
+public class StateEnableConverter : EngineTypeYamlConverterBase<IStateEnable>
 {
     public override IStateEnable? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/TypeContainerConverter.cs

@@ -9,7 +9,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class TypeContainerConverter : EngineTypeYamlSerializerBase<TypeContainer>
+public class TypeContainerConverter : EngineTypeYamlConverterBase<TypeContainer>
 {
     public override TypeContainer Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/UniverseConverter.cs

@@ -11,7 +11,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class UniverseConverter : EngineTypeYamlSerializerBase<IUniverse>
+public class UniverseConverter : EngineTypeYamlConverterBase<IUniverse>
 {
     public override IUniverse? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/Converters/UniverseObjectConverter.cs

@@ -11,7 +11,7 @@ using YamlDotNet.Serialization;
 
 namespace Engine.Serializers.Yaml;
 
-public class UniverseObjectSerializer : EngineTypeYamlSerializerBase<IUniverseObject>
+public class UniverseObjectConverter : EngineTypeYamlConverterBase<IUniverseObject>
 {
     public override IUniverseObject? Read(IParser parser, Type type, ObjectDeserializer rootDeserializer)
     {

Engine.Integration/Engine.Integration.Yaml/YamlConfiguration.cs

@@ -0,0 +1,44 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+using Engine.Core.Config;
+
+namespace Engine.Serializers.Yaml;
+
+public class YamlConfiguration : BasicConfiguration
+{
+    public readonly string FilePath;
+
+    private readonly YamlSerializer yamlSerializer = new();
+
+    public YamlConfiguration(string filePath)
+    {
+        if (!filePath.EndsWith(".yaml"))
+            filePath += ".yaml";
+
+        FilePath = filePath;
+
+        bool isRelativePath = Path.GetFullPath(filePath).CompareTo(filePath) != 0;
+
+        if (isRelativePath)
+            FilePath = Path.GetFullPath(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, filePath));
+
+        if (Path.GetDirectoryName(FilePath) is string directoryPath)
+            Directory.CreateDirectory(directoryPath);
+
+        if (!File.Exists(FilePath))
+            return;
+
+        string yamlFileText = File.ReadAllText(FilePath);
+        Dictionary<string, string> valuePairs = yamlSerializer.Deserialize<Dictionary<string, string>>(yamlFileText);
+
+        foreach ((string key, string value) in valuePairs)
+            Set(key, value);
+    }
+
+    public void Save()
+    {
+        File.WriteAllText(FilePath, yamlSerializer.Serialize(Values));
+    }
+}

Engine.Integration/Engine.Integration.Yaml/YamlSerializer.cs

@@ -62,65 +62,65 @@ public class YamlSerializer : Core.Serialization.ISerializer
         }
     }
 
-    public object Deserialize(string configuration)
+    public object Deserialize(string content)
     {
         lock (Lock)
         {
             identifiableRegistry.Reset();
-            object result = deserializer.Deserialize(configuration)!;
+            object result = deserializer.Deserialize(content)!;
             identifiableRegistry.AssignAll();
             return result;
         }
     }
 
-    public object Deserialize(string configuration, Type type)
+    public object Deserialize(string content, Type type)
     {
         lock (Lock)
         {
             identifiableRegistry.Reset();
-            object result = deserializer.Deserialize(configuration, type)!;
+            object result = deserializer.Deserialize(content, type)!;
             identifiableRegistry.AssignAll();
             return result;
         }
     }
 
-    public T Deserialize<T>(string configuration)
+    public T Deserialize<T>(string content)
     {
         lock (Lock)
         {
             identifiableRegistry.Reset();
-            T result = deserializer.Deserialize<T>(configuration);
+            T result = deserializer.Deserialize<T>(content);
             identifiableRegistry.AssignAll();
             return result;
         }
     }
 
-    public ProgressiveTask<object> DeserializeAsync(string configuration)
+    public ProgressiveTask<object> DeserializeAsync(string content)
     {
         lock (Lock)
         {
             progressionTracker.Reset();
-            Task<object> task = Task.Run(() => Deserialize(configuration));
+            Task<object> task = Task.Run(() => Deserialize(content));
             return new ProgressiveTask<object>(progressionTracker, task);
         }
     }
 
-    public ProgressiveTask<object> DeserializeAsync(string configuration, Type type)
+    public ProgressiveTask<object> DeserializeAsync(string content, Type type)
     {
         lock (Lock)
         {
             progressionTracker.Reset();
-            Task<object> task = Task.Run(() => Deserialize(configuration, type));
+            Task<object> task = Task.Run(() => Deserialize(content, type));
             return new ProgressiveTask<object>(progressionTracker, task);
         }
     }
 
-    public ProgressiveTask<T> DeserializeAsync<T>(string configuration)
+    public ProgressiveTask<T> DeserializeAsync<T>(string content)
     {
         lock (Lock)
         {
             progressionTracker.Reset();
-            Task<T> task = Task.Run(() => Deserialize<T>(configuration));
+            Task<T> task = Task.Run(() => Deserialize<T>(content));
             return new ProgressiveTask<T>(progressionTracker, task);
         }
     }
@@ -135,8 +135,8 @@ public class YamlSerializer : Core.Serialization.ISerializer
         }
     }
 
-    internal object InternalDeserialize(string configuration, Type type)
+    internal object InternalDeserialize(string content, Type type)
     {
-        return deserializer.Deserialize(configuration, type)!;
+        return deserializer.Deserialize(content, type)!;
     }
 }

Engine.Physics2D/Abstract/ICollider2D.cs

@@ -7,6 +7,11 @@ namespace Engine.Physics2D;
 /// </summary>
 public interface ICollider2D : IBehaviour
 {
+    /// <summary>
+    /// Event triggered when the collider is recalculated.
+    /// </summary>
+    Event<ICollider2D> OnRecalculated { get; }
+
     /// <summary>
     /// Event triggered when a collision is detected.
     /// </summary>
@@ -30,6 +35,16 @@ public interface ICollider2D : IBehaviour
     /// </summary>
     IRigidBody2D? RigidBody2D { get; }
 
+    /// <summary>
+    /// The area of the <see cref="ICollider2D"/>.
+    /// </summary>
+    float Area { get; }
+
+    /// <summary>
+    /// The geometric inertia of the <see cref="ICollider2D"/>.
+    /// </summary>
+    float GeometricInertia { get; }
+
     /// <summary>
     /// The value indicating whether the <see cref="ICollider2D"/> is a trigger.
     /// </summary>

Engine.Physics2D/Abstract/IRigidBody2D.cs

@@ -27,6 +27,21 @@ public interface IRigidBody2D : IBehaviour2D
     /// </summary>
     float Mass { get; set; }
 
+    /// <summary>
+    /// The inverse mass (1 / Mass) of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float InverseMass { get; }
+
+    /// <summary>
+    /// The Invertia of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float Inertia { get; }
+
+    /// <summary>
+    /// The inverse Invertia (1 / Invertia) of the <see cref="IRigidBody2D"/>.
+    /// </summary>
+    float InverseInertia { get; }
+
     /// <summary>
     /// The value indicating whether the <see cref="IRigidBody2D"/> is static/immovable.
     /// </summary>

Engine.Physics2D/Collider2DBase.cs

@@ -4,6 +4,7 @@ namespace Engine.Physics2D;
 
 public abstract class Collider2DBase : Behaviour2D, ICollider2D
 {
+    public Event<ICollider2D> OnRecalculated { get; } = new();
     public Event<ICollider2D, CollisionDetectionInformation> OnCollisionDetected { get; } = new();
     public Event<ICollider2D, CollisionDetectionInformation> OnCollisionResolved { get; } = new();
     public Event<ICollider2D, ICollider2D> OnTriggered { get; } = new();
@@ -20,6 +21,9 @@ public abstract class Collider2DBase : Behaviour2D, ICollider2D
     public IRigidBody2D? RigidBody2D { get; protected set; } = null;
     public bool IsTrigger { get; set; } = false;
 
+    public abstract float Area { get; }
+    public abstract float GeometricInertia { get; }
+
     public void Recalculate()
     {
         if (!NeedsRecalculation)
@@ -27,6 +31,7 @@ public abstract class Collider2DBase : Behaviour2D, ICollider2D
 
         CalculateCollider();
         NeedsRecalculation = false;
+        OnRecalculated.Invoke(this);
     }
 
     public abstract void CalculateCollider();

Engine.Physics2D/Collider2DCircle.cs

@@ -15,7 +15,15 @@ public class Collider2DCircle : Collider2DBase, ICircleCollider2D
         }
     } = Circle.UnitCircle;
 
-    public override void CalculateCollider() => CircleWorld = Transform.Transform(CircleLocal);
+    private float area = 0f; public override float Area => area;
+    private float geometricInertia = 0f; public override float GeometricInertia => geometricInertia;
+
+    public override void CalculateCollider()
+    {
+        CircleWorld = Transform.Transform(CircleLocal);
+        area = CircleWorld.Area;
+        geometricInertia = CircleWorld.GeometricInertia;
+    }
 
     public Collider2DCircle() { }
     public Collider2DCircle(Circle circle) => CircleLocal = circle;

Engine.Physics2D/Collider2DShape.cs

@@ -15,7 +15,16 @@ public class Collider2DShape : Collider2DBase, IShapeCollider2D
         }
     } = Shape2D.Square;
 
-    public override void CalculateCollider() => ShapeLocal.Transform(Transform, ShapeWorld);
+    private float area = 0f; public override float Area => area;
+    private float geometricInertia = 0f; public override float GeometricInertia => geometricInertia;
+
+    public override void CalculateCollider()
+    {
+        ShapeLocal.Transform(Transform, ShapeWorld);
+
+        area = ShapeWorld.Area;
+        geometricInertia = ShapeWorld.GetGeometricInertia(Transform.Position);
+    }
 
     public Collider2DShape() { }
     public Collider2DShape(Shape2D shape) { ShapeLocal = shape; }

Engine.Physics2D/CollisionDetectionInformation.cs

@@ -7,14 +7,16 @@ public readonly struct CollisionDetectionInformation
 (
     ICollider2D Detector,
     ICollider2D Detected,
+    Vector2D ContactPoint,
     Vector2D Normal,
     float Penetration
 )
 {
     public ICollider2D Detector { get; init; } = Detector;
     public ICollider2D Detected { get; init; } = Detected;
+    public Vector2D ContactPoint { get; init; } = ContactPoint;
     public Vector2D Normal { get; init; } = Normal;
     public float Penetration { get; init; } = Penetration;
 
-    public CollisionDetectionInformation Reverse() => new(Detected, Detector, -Normal, Penetration);
+    public CollisionDetectionInformation Reverse() => new(Detected, Detector, ContactPoint, -Normal, Penetration);
 }

Engine.Physics2D/CollisionDetector2D.cs

@@ -1,3 +1,5 @@
+using System.Collections.Generic;
+
 using Engine.Core;
 using Engine.Physics2D;
 
@@ -41,12 +43,13 @@ public class CollisionDetector2D : ICollisionDetector2D
 
     private static bool DetectShapeShapeOneWay(IShapeCollider2D left, IShapeCollider2D right, ref CollisionDetectionInformation collisionInformation)
     {
-        System.Collections.Generic.IReadOnlyList<Vector2D> vertices = left.ShapeWorld.Vertices;
+        IReadOnlyList<Vector2D> vertices = left.ShapeWorld.Vertices;
         int count = vertices.Count;
 
         for (int indexProjection = 0; indexProjection < count; indexProjection++)
         {
-            Vector2D projectionVector = vertices[indexProjection].FromTo(vertices[(indexProjection + 1) % count]).Perpendicular().Normalized;
+            Vector2D leftEdge = vertices[indexProjection].FromTo(vertices[(indexProjection + 1) % count]);
+            Vector2D projectionVector = leftEdge.Perpendicular().Normalized;
 
             Projection1D leftProjection = left.ShapeWorld.ToProjection(projectionVector);
             Projection1D rightProjection = right.ShapeWorld.ToProjection(projectionVector);
@@ -55,17 +58,61 @@ public class CollisionDetector2D : ICollisionDetector2D
                 return false;
 
             if (collisionInformation.Detector is null || Math.Abs(collisionInformation.Penetration) > Math.Abs(depth))
-                collisionInformation = new(left, right, projectionVector, depth);
+            {
+                Vector2D contactPoint = FindShapeToShapeContactPoint(left, right, projectionVector);
+                collisionInformation = new(left, right, contactPoint, projectionVector, depth);
+            }
         }
 
         return true;
     }
 
+    private static Vector2D FindShapeToShapeContactPoint(IShapeCollider2D left, IShapeCollider2D right, Vector2D contactProjectionVector)
+    {
+        IReadOnlyList<Vector2D> leftVertices = left.ShapeWorld.Vertices;
+        IReadOnlyList<Vector2D> rightVertices = right.ShapeWorld.Vertices;
+
+        Line2D leftSupportLine = GetSupportLine(leftVertices, contactProjectionVector);
+        Line2D rightSupportLine = GetSupportLine(rightVertices, -contactProjectionVector);
+
+        if (leftSupportLine.Direction.Dot(rightSupportLine.Direction).Abs() > .99f)
+            return (leftSupportLine.From + leftSupportLine.To + rightSupportLine.From + rightSupportLine.To) / 4f;
+
+        return leftSupportLine.IntersectionPoint(rightSupportLine);
+    }
+
+    private static Line2D GetSupportLine(IReadOnlyList<Vector2D> vertices, Vector2D contactProjectionVector)
+    {
+        System.Span<Vector2D> points = stackalloc Vector2D[2];
+        System.Span<float> distances = stackalloc float[2] { float.MaxValue, float.MaxValue };
+        for (int i = 0; i < vertices.Count; i++)
+        {
+            Vector2D point = vertices[i];
+            float distance = contactProjectionVector.Dot(point);
+
+            if (distance < distances[0])
+            {
+                points[1] = points[0];
+                distances[1] = distances[0];
+
+                points[0] = point;
+                distances[0] = distance;
+            }
+            else if (distance < distances[1])
+            {
+                points[1] = point;
+                distances[1] = distance;
+            }
+        }
+
+        return new(points[0], points[1]);
+    }
+
     private static bool DetectShapeCircle(IShapeCollider2D shapeCollider, ICircleCollider2D circleCollider, out CollisionDetectionInformation collisionInformation)
     {
         collisionInformation = default;
 
-        System.Collections.Generic.IReadOnlyList<Vector2D> vertices = shapeCollider.ShapeWorld.Vertices;
+        IReadOnlyList<Vector2D> vertices = shapeCollider.ShapeWorld.Vertices;
         int count = vertices.Count;
 
         for (int indexProjection = 0; indexProjection < count; indexProjection++)
@@ -78,8 +125,10 @@ public class CollisionDetector2D : ICollisionDetector2D
             if (!shapeProjection.Overlaps(circleProjection, out float depth))
                 return false;
 
+            Vector2D contactPoint = circleCollider.CircleWorld.Center + projectionVector * circleCollider.CircleWorld.Radius;
+
             if (collisionInformation.Detector is null || Math.Abs(collisionInformation.Penetration) > Math.Abs(depth))
-                collisionInformation = new(shapeCollider, circleCollider, projectionVector, depth);
+                collisionInformation = new(shapeCollider, circleCollider, contactPoint, projectionVector, depth);
         }
 
         {
@@ -91,8 +140,10 @@ public class CollisionDetector2D : ICollisionDetector2D
             if (!shapeProjection.Overlaps(circleProjection, out float depth))
                 return false;
 
+            Vector2D contactPoint = circleCollider.CircleWorld.Center + shapeToCircleProjectionVector * circleCollider.CircleWorld.Radius;
+
             if (collisionInformation.Detector is null || Math.Abs(collisionInformation.Penetration) > Math.Abs(depth))
-                collisionInformation = new(shapeCollider, circleCollider, shapeToCircleProjectionVector, depth);
+                collisionInformation = new(shapeCollider, circleCollider, contactPoint, shapeToCircleProjectionVector, depth);
         }
 
         return true;
@@ -110,7 +161,10 @@ public class CollisionDetector2D : ICollisionDetector2D
         bool collision = leftProjection.Overlaps(rightProjection, out float depth);
 
         if (collision)
-            collisionInformation = new(left, right, leftToRightCenterProjectionVector, depth);
+        {
+            Vector2D contactPoint = left.CircleWorld.Center + leftToRightCenterProjectionVector * left.CircleWorld.Radius;
+            collisionInformation = new(left, right, contactPoint, leftToRightCenterProjectionVector, depth);
+        }
 
         return collision;
     }

Engine.Physics2D/CollisionResolver2D.cs

@@ -6,8 +6,6 @@ public class CollisionResolver2D : ICollisionResolver2D
 {
     public void Resolve(CollisionDetectionInformation collisionInformation)
     {
-        Vector2D displacementVector = collisionInformation.Normal * collisionInformation.Penetration;
-
         ICollider2D left = collisionInformation.Detector;
         ICollider2D right = collisionInformation.Detected;
 
@@ -17,6 +15,20 @@ public class CollisionResolver2D : ICollisionResolver2D
         if (isLeftStatic && isRightStatic)
             return;
 
+        Displace(collisionInformation, left, right, isLeftStatic, isRightStatic);
+        Bounce(collisionInformation, left, right, isLeftStatic, isRightStatic);
+
+        left.Recalculate();
+        right.Recalculate();
+
+        left.Resolve(collisionInformation);
+        right.Resolve(collisionInformation);
+    }
+
+    private static void Displace(CollisionDetectionInformation collisionInformation, ICollider2D left, ICollider2D right, bool isLeftStatic, bool isRightStatic)
+    {
+        Vector2D displacementVector = collisionInformation.Normal * collisionInformation.Penetration;
+
         if (isLeftStatic)
             right.Transform.Position += displacementVector;
         else if (isRightStatic)
@@ -33,11 +45,32 @@ public class CollisionResolver2D : ICollisionResolver2D
             right.Transform.Position += leftMomentumPercentage * displacementVector;
             left.Transform.Position -= rightMomentumPercentage * displacementVector;
         }
+    }
 
-        left.Recalculate();
-        right.Recalculate();
+    private static void Bounce(CollisionDetectionInformation collisionInformation, ICollider2D left, ICollider2D right, bool isLeftStatic, bool isRightStatic)
+    {
+        Vector2D leftVelocity = left.RigidBody2D?.Velocity ?? Vector2D.Zero;
+        Vector2D rightVelocity = right.RigidBody2D?.Velocity ?? Vector2D.Zero;
 
-        left.Resolve(collisionInformation);
-        right.Resolve(collisionInformation);
+        Vector2D relativeVelocity = leftVelocity - rightVelocity;
+        float velocityAlongNormal = Vector2D.Dot(relativeVelocity, collisionInformation.Normal);
+
+        if (velocityAlongNormal > 0)
+        {
+            collisionInformation = collisionInformation.Reverse();
+            velocityAlongNormal = -velocityAlongNormal;
+        }
+
+        float e = (left.RigidBody2D?.Material.Restitution ?? 0f).Add(right.RigidBody2D?.Material.Restitution ?? 0f).Divide(2f);
+
+        float leftMassEffective = isLeftStatic ? float.PositiveInfinity : left.RigidBody2D?.Mass ?? float.Epsilon;
+        float rightMassEffective = isRightStatic ? float.PositiveInfinity : right.RigidBody2D?.Mass ?? float.Epsilon;
+        float impulse = -(1f + e) * velocityAlongNormal / ((1f / leftMassEffective) + (1f / rightMassEffective));
+
+        if (!isLeftStatic)
+            left.RigidBody2D?.Velocity += impulse / leftMassEffective * collisionInformation.Normal;
+
+        if (!isRightStatic)
+            right.RigidBody2D?.Velocity -= impulse / rightMassEffective * collisionInformation.Normal;
     }
 }

Engine.Physics2D/PhysicsMaterial2D.cs

@@ -1,7 +1,7 @@
 namespace Engine.Physics2D;
 
-public readonly struct PhysicsMaterial2D(float Friction, float Restitution) : IPhysicsMaterial2D
+public class PhysicsMaterial2D(float Friction, float Restitution) : IPhysicsMaterial2D
 {
-    public readonly float Friction { get; init; } = Friction;
-    public readonly float Restitution { get; init; } = Restitution;
+    public float Friction { get; set; } = Friction;
+    public float Restitution { get; set; } = Restitution;
 }

Engine.Physics2D/PhysicsMaterial2DDefault.cs

@@ -1,8 +0,0 @@
-namespace Engine.Physics2D;
-
-public readonly struct PhysicsMaterial2DDefault : IPhysicsMaterial2D
-{
-    public readonly float Friction => .1f;
-
-    public readonly float Restitution => .1f;
-}

Engine.Physics2D/ReadOnlyPhysicsMaterial2D.cs

@@ -0,0 +1,9 @@
+namespace Engine.Physics2D;
+
+public readonly struct ReadOnlyPhysicsMaterial2D(float Friction, float Restitution) : IPhysicsMaterial2D
+{
+    public readonly float Friction { get; } = Friction;
+    public readonly float Restitution { get; } = Restitution;
+
+    public readonly static ReadOnlyPhysicsMaterial2D Default = new(.1f, .1f);
+}

Engine.Physics2D/RigidBody2D.cs

@@ -1,16 +1,75 @@
+using System.Collections.Generic;
+
 using Engine.Core;
 
 namespace Engine.Physics2D;
 
-public class RigidBody2D : Behaviour2D, IRigidBody2D
+public class RigidBody2D : Behaviour2D, IRigidBody2D, IFirstFrameUpdate, ILastFrameUpdate
 {
     private const float LOWEST_ALLOWED_MASS = 0.00001f;
 
-    public IPhysicsMaterial2D Material { get; set; } = new PhysicsMaterial2DDefault();
+    public IPhysicsMaterial2D Material { get; set; } = ReadOnlyPhysicsMaterial2D.Default;
 
     public Vector2D Velocity { get; set; } = Vector2D.Zero;
     public float AngularVelocity { get; set; } = 0f;
     public bool IsStatic { get; set; } = false;
 
-    public float Mass { get; set => field = Math.Max(value, LOWEST_ALLOWED_MASS); } = 1f;
+    public float Mass { get; set { field = Math.Max(value, LOWEST_ALLOWED_MASS); } } = 1f;
+    public float InverseMass { get; protected set; } = 1f;
+
+    public float Inertia { get; protected set; } = 1f;
+    public float InverseInertia { get; protected set; } = 1f;
+
+    private readonly List<ICollider2D> childColliders = [];
+
+    public void LastActiveFrame() => DisconnectColliders();
+    public void FirstActiveFrame()
+    {
+        ReconnectColliders();
+        UpdateValues();
+    }
+
+    private void ReconnectColliders()
+    {
+        DisconnectColliders();
+
+        BehaviourController.GetBehavioursInChildren(childColliders);
+
+        foreach (ICollider2D collider in childColliders)
+            collider.OnRecalculated.AddListener(RecalculateCallback);
+    }
+
+    private void DisconnectColliders()
+    {
+        foreach (ICollider2D collider in childColliders)
+            collider.OnRecalculated.RemoveListener(RecalculateCallback);
+    }
+
+    private void RecalculateCallback(ICollider2D _) => UpdateValues();
+    private void UpdateValues()
+    {
+        InverseMass = Mass.OneOver();
+
+        Vector2D center = Transform.Position;
+        Inertia = 0f;
+
+        float totalColliderArea = 0f;
+
+        foreach (ICollider2D collider in childColliders)
+            totalColliderArea += collider.Area;
+
+        foreach (ICollider2D collider in childColliders)
+        {
+            float colliderMass = Mass * (collider.Area / totalColliderArea);
+            float colliderInertia = collider.GeometricInertia * colliderMass;
+            float distanceSquared = center.FromTo(collider.Transform.Position).MagnitudeSquared;
+
+            Inertia += colliderInertia + colliderMass * distanceSquared;
+        }
+
+        if (childColliders.Count == 0)
+            Inertia = 1f;
+
+        InverseInertia = Inertia.OneOver();
+    }
 }

Engine.Systems/Graphics/TriangleBatcher.cs

@@ -10,14 +10,10 @@ public class TriangleBatcher : Behaviour, IFirstFrameUpdate, ILastFrameUpdate, I
     private static System.Func<IBehaviour, int> GetPriority() => (b) => b.Priority;
 
     private readonly BehaviourCollector<ITriangleBatch> triangleBatches = new();
-    private ICamera camera = null!;
-
     private readonly ActiveBehaviourCollectorOrdered<int, IDrawableTriangle> drawableShapes = new(GetPriority(), SortByAscendingPriority());
 
     public void FirstActiveFrame()
     {
-        camera = Universe.FindRequiredBehaviour<ICamera>();
-
         drawableShapes.Assign(Universe);
         triangleBatches.Assign(Universe);
     }
@@ -27,7 +23,7 @@ public class TriangleBatcher : Behaviour, IFirstFrameUpdate, ILastFrameUpdate, I
         for (int i = 0; i < triangleBatches.Count; i++)
         {
             ITriangleBatch triangleBatch = triangleBatches[i];
-            triangleBatch.Begin(camera.ViewMatrix, camera.ProjectionMatrix);
+            triangleBatch.Begin();
             for (int j = 0; j < drawableShapes.Count; j++)
                 drawableShapes[j].Draw(triangleBatch);
             triangleBatch.End();

Engine.Systems/Network/Abstract/IPacketListenerClientEntity.cs

@@ -0,0 +1,6 @@
+namespace Engine.Systems.Network;
+
+public interface IPacketListenerClientEntity<T> : INetworkEntity where T : IEntityNetworkPacket
+{
+    void OnEntityClientPacketArrived(IConnection sender, T packet);
+}

Engine.Systems/Network/Abstract/IPacketListenerServerEntity.cs

@@ -0,0 +1,6 @@
+namespace Engine.Systems.Network;
+
+public interface IPacketListenerServerEntity<T> : INetworkEntity where T : IEntityNetworkPacket
+{
+    void OnEntityServerPacketArrived(IConnection sender, T packet);
+}

Engine.Systems/Network/CommonNetworkBehaviour.cs

@@ -0,0 +1,40 @@
+using Engine.Core;
+
+namespace Engine.Systems.Network;
+
+/// <summary>
+/// Basic network behaviour that supports both client & server behaviour. Finds both 
+/// the <see cref="INetworkCommunicatorClient"/> and the <see cref="INetworkCommunicatorServer"/> 
+/// in the universe in it's first active frame. Recommended to use <see cref="ClientBehaviour"/> or <see cref="ServerBehaviour"/>
+/// <br/> 
+/// Disclaimer: It implements <see cref="IFirstFrameUpdate"/> and <see cref="ILastFrameUpdate"/> in virtual methods.
+/// </summary>
+public class CommonNetworkBehaviour : Behaviour, IFirstFrameUpdate, ILastFrameUpdate
+{
+    protected INetworkCommunicatorServer? server = null!;
+    protected INetworkCommunicatorClient? client = null!;
+
+    protected bool IsServer { get; private set; } = false;
+    protected bool IsClient { get; private set; } = false;
+
+    public INetworkCommunicatorServer Server => server ?? throw new Core.Exceptions.NotFoundException($"Universe does not contain a {nameof(INetworkCommunicatorServer)}");
+    public INetworkCommunicatorClient Client => client ?? throw new Core.Exceptions.NotFoundException($"Universe does not contain a {nameof(INetworkCommunicatorClient)}");
+
+    public virtual void FirstActiveFrame()
+    {
+        client = Universe.FindBehaviour<INetworkCommunicatorClient>();
+        server = Universe.FindBehaviour<INetworkCommunicatorServer>();
+
+        IsServer = server is not null;
+        IsClient = client is not null;
+    }
+
+    public virtual void LastActiveFrame()
+    {
+        client = null!;
+        server = null!;
+
+        IsServer = false;
+        IsClient = false;
+    }
+}

Engine.Systems/Network/Extensions/CommunicatorExtensions.cs

@@ -0,0 +1,13 @@
+
+using System.Collections.Generic;
+
+namespace Engine.Systems.Network;
+
+public static class CommunicatorExtensions
+{
+    public static void SendToClients<T>(this INetworkCommunicatorServer server, IEnumerable<IConnection> connections, T packet, PacketDelivery packetDelivery = PacketDelivery.ReliableInOrder) where T : class, new()
+    {
+        foreach (IConnection connection in connections)
+            server.SendToClient(connection, packet, packetDelivery);
+    }
+}

Engine.Systems/Network/NetworkManager.cs

@@ -10,25 +10,127 @@ namespace Engine.Systems.Network;
 /// <summary>
 /// Intermediary manager that looks up in it's hierarchy for a <see cref="INetworkCommunicator"/> to route/broadcast it's received packets to their destinations.
 /// </summary>
+/// TODO: I need to peer check this class, I don't exactly remember the state I was in when I was originally writing it and left it uncommented and the current comments are added later on.
+/// It's a fairly complex manager that relies heavily on Reflection and lots of generic method delegation which is making it very hard to read back. 
 public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetworkManager
 {
-    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> clientPacketArrivalMethods = [];
-    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> serverPacketArrivalMethods = [];
+    #region Packet Router/Broadcaster to Listener Delegates
 
-    private readonly Dictionary<Type, Dictionary<string, object>> clientPacketRouters = [];
-    private readonly Dictionary<Type, Dictionary<string, object>> serverPacketRouters = [];
+    /// <summary>
+    /// Behaviour Type → Packet Type → List of <see cref="IPacketListenerClient{T}"/> listener methods (broadcast packets, client-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> clientBroadcastPacketListenerMethods = [];
 
-    private readonly List<(Type packetType, Delegate @delegate)> packetRetrievalDelegates = [];
+    /// <summary>
+    /// Behaviour Type → Packet Type → List of <see cref="IPacketListenerServer{T}"/> listener methods (broadcast packets, server-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> serverBroadcastPacketListenerMethods = [];
 
+    /// <summary>
+    /// Behaviour Type → Packet Type → List of <see cref="IPacketListenerClientEntity{T}"/> listener methods (entity packets, client-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> clientEntityPacketListenerMethods = [];
+
+    /// <summary>
+    /// Behaviour Type → Packet Type → List of <see cref="IPacketListenerServerEntity{T}"/> listener methods (entity packets, server-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<Type, List<MethodInfo>>> serverEntityPacketListenerMethods = [];
+
+    #endregion 
+
+    #region Packet Router/Broadcaster Events
+
+    /// <summary>
+    /// Packet Type → Behaviour.Id → Broadcaster Event (broadcast, client-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<string, object>> clientPacketBroadcastEvents = [];
+
+    /// <summary>
+    /// Packet Type → Behaviour.Id → Broadcaster Event (broadcast, server-side)
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<string, object>> serverPacketBroadcastEvents = [];
+
+    /// <summary>
+    /// Maps an <see cref="IEntityNetworkPacket"/> type to a set of routing events,
+    /// keyed by <see cref="IIdentifiable.Id"/>, for CLIENT entity listeners.
+    /// The packet is routed to the correct <see cref="INetworkEntity"/> instance
+    /// by matching <see cref="IEntityNetworkPacket.EntityId"/>.
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<string, object>> clientEntityPacketRouterEvents = [];
+
+    /// <summary>
+    /// Maps an <see cref="IEntityNetworkPacket"/> type to a set of routing events,
+    /// keyed by <see cref="IIdentifiable.Id"/>, for SERVER entity listeners.
+    /// The packet is routed to the correct <see cref="INetworkEntity"/> instance
+    /// by matching <see cref="IEntityNetworkPacket.EntityId"/>.
+    /// </summary>
+    private readonly Dictionary<Type, Dictionary<string, object>> serverEntityPacketRouterEvents = [];
+
+    #endregion 
+
+    #region Packet Retrieval Delegates
+
+    /// <summary>
+    /// Stores delegates that connect incoming broadcast packets from <see cref="INetworkCommunicator"/>
+    /// to <see cref="OnPacketReceived{T}(IConnection, T)"/>. 
+    /// These are used to subscribe/unsubscribe from <see cref="INetworkCommunicator"/> events.
+    /// </summary>
+    private readonly List<PacketRetrievalDelegatePair> broadcastPacketRetrievalSubscriptionDelegates = [];
+
+    /// <summary>
+    /// Stores delegates that connect incoming entity packets from <see cref="INetworkCommunicator"/>
+    /// to <see cref="OnPacketReceived{T}(IConnection, T)"/>. 
+    /// These are used to subscribe/unsubscribe from <see cref="INetworkCommunicator"/> events.
+    /// </summary>
+    private readonly List<PacketRetrievalDelegatePair> entityPacketRetrievalSubscriptionDelegates = [];
+
+    /// <summary>
+    /// Stores delegates that connect incoming all packets from <see cref="INetworkCommunicator"/> to 
+    /// <see cref="OnPacketReceived{T}(IConnection, T)"/>. This is a combination of all subscription 
+    /// delegates filtered so there are no duplicates packet entries.
+    /// </summary>
+    private readonly List<PacketRetrievalDelegatePair> uniqueRetrievalSubscriptionDelegates = [];
+
+    #endregion
+
+    #region Method Caches
+
+    /// <summary>
+    /// Packet type → <see cref="ClearRouter{T}(object)"/> method.
+    /// </summary>
     private readonly Dictionary<Type, MethodInfo> clearRoutesMethods = [];
-    private readonly Dictionary<Type, MethodInfo> registerPacketListenersMethods = [];
 
+    /// <summary>
+    /// Packet type → <see cref="RegisterBroadcastPacketListenerEvent{T}(INetworkEntity, Event{IConnection, T}, NetworkType)"/> method.
+    /// </summary>
+    private readonly Dictionary<Type, MethodInfo> registerBroadcastPacketListenersMethods = [];
+
+    /// <summary>
+    /// Packet type → <see cref="RegisterEntityPacketListenerEvent{T}(INetworkEntity, Event{IConnection, T}, NetworkType)"/> method.
+    /// </summary>
+    private readonly Dictionary<Type, MethodInfo> registerEntityPacketListenersMethods = [];
+
+    #endregion 
+
+    #region Network Entity Collector
+
+    /// <summary>
+    /// All active network <see cref="INetworkEntity"/>, keyed by <see cref="IIdentifiable.Id"/>.
+    /// </summary>
     private readonly Dictionary<string, INetworkEntity> _networkEntities = [];
     public IReadOnlyDictionary<string, INetworkEntity> NetworkEntities => _networkEntities;
 
+    /// <summary>
+    /// Collector responsible for detecting <see cref="INetworkEntity"/>s entering/leaving the universe.
+    /// </summary>
     private readonly BehaviourCollector<INetworkEntity> _networkEntityCollector = new();
+
     public IBehaviourCollector<INetworkEntity> NetworkEntityCollector => _networkEntityCollector;
 
+    #endregion
+
+    #region Network Communicator
+
     public INetworkCommunicator NetworkCommunicator
     {
         get;
@@ -40,68 +142,74 @@ public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetwork
             INetworkCommunicator? previousCommunicator = field;
             field = value;
 
-            if (previousCommunicator is not null) UnsubscribeCommunicatorMethods(previousCommunicator);
-            if (field is not null) SubscribeCommunicatorMethods(field);
+            // Unsubscribe packet delegates from old communicator
+            if (previousCommunicator is not null)
+                InvokeCommunicatorMethods(nameof(INetworkCommunicator.UnsubscribeFromPackets), previousCommunicator);
+
+            // Subscribe packet delegates to new communicator
+            if (field is not null)
+                InvokeCommunicatorMethods(nameof(INetworkCommunicator.SubscribeToPackets), field);
         }
     } = null!;
 
-    #region Communicator Subscriptions
-    private void SubscribeCommunicatorMethods(INetworkCommunicator networkCommunicator)
-    {
-        MethodInfo subscribeToPacketsMethod = typeof(INetworkCommunicator)
-            .GetMethod(nameof(INetworkCommunicator.SubscribeToPackets), BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance)!;
-
-        foreach ((Type packetType, Delegate @delegate) in packetRetrievalDelegates)
-        {
-            MethodInfo genericSubscribeMethod = subscribeToPacketsMethod.MakeGenericMethod(packetType);
-            genericSubscribeMethod.Invoke(networkCommunicator, [@delegate]);
-        }
-    }
-
-    private void UnsubscribeCommunicatorMethods(INetworkCommunicator networkCommunicator)
+    /// <summary>
+    /// Dynamically invokes <see cref="INetworkCommunicator.SubscribeToPackets{T}(Event{IConnection, T}.EventHandler)"/> 
+    /// or <see cref="INetworkCommunicator.UnsubscribeFromPackets{T}(Event{IConnection, T}.EventHandler)"/>
+    /// on the provided <see cref="INetworkCommunicator"/> for all known packet types.
+    /// </summary>
+    private void InvokeCommunicatorMethods(string methodName, INetworkCommunicator networkCommunicator)
     {
         MethodInfo unsubscribeFromPacketsMethod = typeof(INetworkCommunicator)
-            .GetMethod(nameof(INetworkCommunicator.UnsubscribeFromPackets), BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance)!;
+            .GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance)!;
 
-        foreach ((Type packetType, Delegate @delegate) in packetRetrievalDelegates)
+        foreach ((Type packetType, Delegate @delegate) in uniqueRetrievalSubscriptionDelegates)
         {
-            MethodInfo genericUnsubscribeMethod = unsubscribeFromPacketsMethod.MakeGenericMethod(packetType);
-            genericUnsubscribeMethod.Invoke(networkCommunicator, [@delegate]);
+            MethodInfo genericMethod = unsubscribeFromPacketsMethod.MakeGenericMethod(packetType);
+            genericMethod.Invoke(networkCommunicator, [@delegate]);
         }
     }
+
     #endregion
 
-    #region Packet Routing
+    ////////////////////////////////////////////////////////////////
+
+    #region Packet Routing/Broadcasting
+
+    /// <summary>
+    /// Entry point for ALL incoming packets from the <see cref="NetworkCommunicator"/>.
+    /// </summary>
     private void OnPacketReceived<T>(IConnection sender, T entityDataPacket)
     {
+        BroadcastPacket(sender, entityDataPacket);
+
         if (entityDataPacket is IEntityNetworkPacket entityPacket)
             RoutePacket(sender, entityDataPacket, entityPacket);
-        else
-            BroadcastPacket(sender, entityDataPacket);
     }
 
     private void RoutePacket<T>(IConnection sender, T entityDataPacket, IEntityNetworkPacket entityPacket)
     {
         if (NetworkCommunicator is INetworkCommunicatorClient)
-            RoutePacket(clientPacketRouters, entityPacket.EntityId, sender, entityDataPacket);
+            RoutePacket(clientEntityPacketRouterEvents, entityPacket.EntityId, sender, entityDataPacket);
+
         if (NetworkCommunicator is INetworkCommunicatorServer)
-            RoutePacket(serverPacketRouters, entityPacket.EntityId, sender, entityDataPacket);
+            RoutePacket(serverEntityPacketRouterEvents, entityPacket.EntityId, sender, entityDataPacket);
     }
 
     private void BroadcastPacket<T>(IConnection sender, T entityDataPacket)
     {
         if (NetworkCommunicator is INetworkCommunicatorClient)
-            BroadcastPacket(clientPacketRouters, sender, entityDataPacket);
+            BroadcastPacket(clientPacketBroadcastEvents, sender, entityDataPacket);
+
         if (NetworkCommunicator is INetworkCommunicatorServer)
-            BroadcastPacket(serverPacketRouters, sender, entityDataPacket);
+            BroadcastPacket(serverPacketBroadcastEvents, sender, entityDataPacket);
     }
 
-    private static void BroadcastPacket<T>(
-        Dictionary<Type, Dictionary<string, object>> packetRouters,
+    private void BroadcastPacket<T>(
+        Dictionary<Type, Dictionary<string, object>> packetBroadcasters,
         IConnection sender,
         T entityDataPacket)
     {
-        if (!packetRouters.TryGetValue(entityDataPacket!.GetType(), out Dictionary<string, object>? routers))
+        if (!packetBroadcasters.TryGetValue(entityDataPacket!.GetType(), out Dictionary<string, object>? routers))
             return;
 
         foreach ((string behaviourId, object routerEventReference) in routers)
@@ -111,7 +219,7 @@ public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetwork
         }
     }
 
-    private static void RoutePacket<T>(
+    private void RoutePacket<T>(
         Dictionary<Type, Dictionary<string, object>> packetRouters,
         string entityId,
         IConnection sender,
@@ -126,65 +234,114 @@ public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetwork
         Event<IConnection, T> routerEvent = (Event<IConnection, T>)routerEventReference;
         routerEvent.Invoke(sender, entityDataPacket!);
     }
+
     #endregion
 
     #region Packet Routers
+
+    /// <summary>
+    /// Registers routing events for the behaviour based on cached packet listener methods.
+    /// </summary>
     private void RegisterPacketRoutersFor(
         INetworkEntity behaviour,
         Dictionary<Type, Dictionary<string, object>> packetRouters,
-        Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetArrivalMethods,
-        NetworkType networkType)
+        Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetListenerMethods,
+        NetworkType networkType,
+        Dictionary<Type, MethodInfo> registerPacketListenerListenersMethods)
     {
-        if (!packetArrivalMethods.TryGetValue(behaviour.GetType(), out Dictionary<Type, List<MethodInfo>>? arrivalMethods))
+        if (!packetListenerMethods.TryGetValue(behaviour.GetType(), out Dictionary<Type, List<MethodInfo>>? listenerMethods))
             return;
 
-        foreach ((Type packetType, List<MethodInfo> methods) in arrivalMethods)
-            foreach (MethodInfo receiveMethod in methods)
+        foreach (Type packetType in listenerMethods.Keys)
+        {
+            if (!packetRouters.TryGetValue(packetType, out Dictionary<string, object>? routers))
             {
-                if (!packetRouters.TryGetValue(packetType, out Dictionary<string, object>? routers))
-                {
-                    routers = [];
-                    packetRouters.Add(packetType, routers);
-                }
-
-                object packetListenerEvent = CreateEventAndRegister(packetType, behaviour, networkType);
-                routers.Add(behaviour.Id, packetListenerEvent);
+                routers = [];
+                packetRouters.Add(packetType, routers);
             }
+
+            object packetListenerEvent = CreateEventAndRegister(packetType, behaviour, networkType, registerPacketListenerListenersMethods);
+
+            routers.Add(behaviour.Id, packetListenerEvent);
+        }
     }
 
-    private object CreateEventAndRegister(Type packetType, INetworkEntity behaviour, NetworkType networkType)
+    /// <summary>
+    /// Creates an Event<IConnection, TPacket> and attaches listener callbacks.
+    /// </summary>
+    private object CreateEventAndRegister(
+        Type packetType,
+        INetworkEntity behaviour,
+        NetworkType networkType,
+        Dictionary<Type, MethodInfo> registerPacketListenersMethods)
     {
         Type genericEventType = typeof(Event<,>).MakeGenericType(typeof(IConnection), packetType);
         object packetListenerEvent = Activator.CreateInstance(genericEventType)!;
 
         if (!registerPacketListenersMethods.TryGetValue(packetType, out MethodInfo? registerPacketListenerMethod))
-            throw new($"{nameof(RegisterPacketListenerEvent)} for {packetType.Name} has not been cached.");
+            throw new($"Packet Listener Events for {packetType.Name} has not been cached.");
 
         registerPacketListenerMethod.Invoke(this, [behaviour, packetListenerEvent, networkType]);
         return packetListenerEvent;
     }
 
-    private static void RegisterPacketListenerEvent<T>(
+    /// <summary>
+    /// Registers broadcast packet listeners on the behaviour.
+    /// </summary>
+    private static void RegisterBroadcastPacketListenerEvent<T>(
         INetworkEntity behaviour,
         Event<IConnection, T> packetListenerEvent,
         NetworkType networkType)
     {
         switch (networkType)
         {
-            case NetworkType.Client: packetListenerEvent.AddListener((sender, packet) => ((IPacketListenerClient<T>)behaviour).OnClientPacketArrived(sender, packet)); break;
-            case NetworkType.Server: packetListenerEvent.AddListener((sender, packet) => ((IPacketListenerServer<T>)behaviour).OnServerPacketArrived(sender, packet)); break;
+            case NetworkType.Client:
+                packetListenerEvent.AddListener(
+                    (sender, packet) => ((IPacketListenerClient<T>)behaviour).OnClientPacketArrived(sender, packet));
+                break;
+
+            case NetworkType.Server:
+                packetListenerEvent.AddListener(
+                    (sender, packet) => ((IPacketListenerServer<T>)behaviour).OnServerPacketArrived(sender, packet));
+                break;
         }
     }
 
+    /// <summary>
+    /// Registers entity-specific packet listeners on a network behaviour.
+    /// </summary>
+    private static void RegisterEntityPacketListenerEvent<T>(
+        INetworkEntity behaviour,
+        Event<IConnection, T> packetListenerEvent,
+        NetworkType networkType
+    ) where T : IEntityNetworkPacket
+    {
+        switch (networkType)
+        {
+            case NetworkType.Client:
+                packetListenerEvent.AddListener(
+                    (sender, packet) => ((IPacketListenerClientEntity<T>)behaviour).OnEntityClientPacketArrived(sender, packet));
+                break;
+
+            case NetworkType.Server:
+                packetListenerEvent.AddListener(
+                    (sender, packet) => ((IPacketListenerServerEntity<T>)behaviour).OnEntityServerPacketArrived(sender, packet));
+                break;
+        }
+    }
+
+    /// <summary>
+    /// Unregisters all routing events associated with the behaviour.
+    /// </summary>
     private void UnregisterPacketRoutersFor(
         INetworkEntity behaviour,
         Dictionary<Type, Dictionary<string, object>> packetRouters,
-        Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetArrivalMethods)
+        Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetListenerMethods)
     {
-        if (!packetArrivalMethods.TryGetValue(behaviour.GetType(), out Dictionary<Type, List<MethodInfo>>? arrivalMethods))
+        if (!packetListenerMethods.TryGetValue(behaviour.GetType(), out Dictionary<Type, List<MethodInfo>>? listenerMethods))
             return;
 
-        foreach ((Type packetType, List<MethodInfo> methods) in arrivalMethods)
+        foreach ((Type packetType, List<MethodInfo> methods) in listenerMethods)
         {
             if (!packetRouters.TryGetValue(packetType, out Dictionary<string, object>? routers))
                 continue;
@@ -199,6 +356,9 @@ public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetwork
         }
     }
 
+    /// <summary>
+    /// Clears all listeners from a router event.
+    /// </summary>
     private static void ClearRouter<T>(object routerEventReference)
     {
         Event<IConnection, T> routerEvent = (Event<IConnection, T>)routerEventReference;
@@ -208,124 +368,192 @@ public class NetworkManager : Behaviour, IEnterUniverse, IExitUniverse, INetwork
     #endregion
 
     #region Engine Callbacks
-    private void OnCollected(IBehaviourCollector<INetworkEntity> sender, IBehaviourCollector<INetworkEntity>.BehaviourCollectedArguments args)
+
+    /// <summary>
+    /// Called when an <see cref="INetworkEntity"/> enters the universe.
+    /// Registers all packet routing for that entity.
+    /// </summary>
+    private void OnCollected(
+        IBehaviourCollector<INetworkEntity> sender,
+        IBehaviourCollector<INetworkEntity>.BehaviourCollectedArguments args)
     {
         INetworkEntity collectedBehaviour = args.BehaviourCollected;
 
         if (!_networkEntities.TryAdd(collectedBehaviour.Id, collectedBehaviour))
             throw new($"Unable to add {collectedBehaviour.Id} to {nameof(NetworkManager)}");
 
-        RegisterPacketRoutersFor(collectedBehaviour, clientPacketRouters, clientPacketArrivalMethods, NetworkType.Client);
-        RegisterPacketRoutersFor(collectedBehaviour, serverPacketRouters, serverPacketArrivalMethods, NetworkType.Server);
+        RegisterPacketRoutersFor(collectedBehaviour, clientPacketBroadcastEvents, clientBroadcastPacketListenerMethods, NetworkType.Client, registerBroadcastPacketListenersMethods);
+        RegisterPacketRoutersFor(collectedBehaviour, clientEntityPacketRouterEvents, clientEntityPacketListenerMethods, NetworkType.Client, registerEntityPacketListenersMethods);
+
+        RegisterPacketRoutersFor(collectedBehaviour, serverPacketBroadcastEvents, serverBroadcastPacketListenerMethods, NetworkType.Server, registerBroadcastPacketListenersMethods);
+        RegisterPacketRoutersFor(collectedBehaviour, serverEntityPacketRouterEvents, serverEntityPacketListenerMethods, NetworkType.Server, registerEntityPacketListenersMethods);
     }
 
+    /// <summary>
+    /// Called when an <see cref="INetworkEntity"/> is removed from the universe.
+    /// Cleans up all routing.
+    /// </summary>
     private void OnRemoved(IBehaviourCollector<INetworkEntity> sender, IBehaviourCollector<INetworkEntity>.BehaviourRemovedArguments args)
     {
         INetworkEntity removedBehaviour = args.BehaviourRemoved;
-        if (!_networkEntities.Remove(args.BehaviourRemoved.Id))
+
+        if (!_networkEntities.Remove(removedBehaviour.Id))
             return;
 
-        UnregisterPacketRoutersFor(removedBehaviour, clientPacketRouters, clientPacketArrivalMethods);
-        UnregisterPacketRoutersFor(removedBehaviour, serverPacketRouters, serverPacketArrivalMethods);
+        UnregisterPacketRoutersFor(removedBehaviour, clientPacketBroadcastEvents, clientBroadcastPacketListenerMethods);
+        UnregisterPacketRoutersFor(removedBehaviour, clientEntityPacketRouterEvents, clientEntityPacketListenerMethods);
+
+        UnregisterPacketRoutersFor(removedBehaviour, serverPacketBroadcastEvents, serverBroadcastPacketListenerMethods);
+        UnregisterPacketRoutersFor(removedBehaviour, serverEntityPacketRouterEvents, serverEntityPacketListenerMethods);
     }
 
     public void ExitUniverse(IUniverse universe) => _networkEntityCollector.Unassign();
+
     public void EnterUniverse(IUniverse universe)
     {
         _networkEntityCollector.Assign(universe);
         NetworkCommunicator = BehaviourController.GetRequiredBehaviourInParent<INetworkCommunicator>();
     }
+
     #endregion
 
     #region Initialization
+
     public NetworkManager()
     {
-        CachePacketRetrievalDelegates();
+        CacheRetrievalSubscriptionDelegates();
         CacheRegistrationMethods();
-        CachePacketArrivalMethods();
+        CachePacketListenerMethods();
 
         _networkEntityCollector.OnCollected.AddListener(OnCollected);
         _networkEntityCollector.OnRemoved.AddListener(OnRemoved);
     }
 
-    private void CachePacketRetrievalDelegates()
+    /// <summary>
+    /// Caches all retrieval subscription delegates for packets.
+    /// </summary>
+    private void CacheRetrievalSubscriptionDelegates()
     {
-        IEnumerable<Type> packetTypes = AppDomain.CurrentDomain.GetAssemblies().SelectMany(a => a.GetTypes())
-            .Where(t => typeof(INetworkPacket).IsAssignableFrom(t) && !t.IsInterface && !t.IsAbstract && !t.IsGenericType);
+        CachePacketRetrievalDelegates(typeof(INetworkPacket), broadcastPacketRetrievalSubscriptionDelegates);
+        CachePacketRetrievalDelegates(typeof(IEntityNetworkPacket), entityPacketRetrievalSubscriptionDelegates);
 
-        MethodInfo onPacketArrivedMethod = GetType()
-            .GetMethod(nameof(OnPacketReceived), BindingFlags.NonPublic | BindingFlags.Instance)!;
+        uniqueRetrievalSubscriptionDelegates.AddRange(broadcastPacketRetrievalSubscriptionDelegates.Concat(entityPacketRetrievalSubscriptionDelegates).DistinctBy(pair => pair.PacketType));
+    }
 
-        foreach (Type packetType in packetTypes)
+    /// <summary>
+    /// Creates delegates for all concrete packet types that forward packets to <see cref="OnPacketReceived{T}(IConnection, T)"/>.
+    /// </summary>
+    private void CachePacketRetrievalDelegates(Type packetType, List<PacketRetrievalDelegatePair> retrievalDelegates)
+    {
+        IEnumerable<Type> packetTypes =
+            AppDomain.CurrentDomain.GetAssemblies()
+                .SelectMany(a => a.GetTypes())
+                .Where(t =>
+                    packetType.IsAssignableFrom(t) &&
+                    !t.IsInterface &&
+                    !t.IsAbstract &&
+                    !t.IsGenericType
+                );
+
+        MethodInfo onPacketArrivedMethod = GetType().GetMethod(nameof(OnPacketReceived), BindingFlags.NonPublic | BindingFlags.Instance)!;
+
+        foreach (Type type in packetTypes)
         {
-            MethodInfo genericOnPacketArrivedMethod = onPacketArrivedMethod.MakeGenericMethod(packetType);
+            MethodInfo genericOnPacketArrivedMethod = onPacketArrivedMethod.MakeGenericMethod(type);
+
+            Type genericDelegateType = typeof(Event<,>.EventHandler).MakeGenericType(typeof(IConnection), type);
 
-            Type genericDelegateType = typeof(Event<,>.EventHandler).MakeGenericType(typeof(IConnection), packetType);
             Delegate genericPacketReceivedDelegate = Delegate.CreateDelegate(genericDelegateType, this, genericOnPacketArrivedMethod);
 
-            packetRetrievalDelegates.Add((packetType, genericPacketReceivedDelegate));
+            retrievalDelegates.Add((type, genericPacketReceivedDelegate));
         }
     }
 
+    /// <summary>
+    /// Caches all registration and cleanup methods for packets.
+    /// </summary>
     private void CacheRegistrationMethods()
     {
-        CacheRegistrationMethods(registerPacketListenersMethods, nameof(RegisterPacketListenerEvent));
-        CacheRegistrationMethods(clearRoutesMethods, nameof(ClearRouter));
+        CacheRegistrationMethods(registerBroadcastPacketListenersMethods, nameof(RegisterBroadcastPacketListenerEvent), broadcastPacketRetrievalSubscriptionDelegates);
+        CacheRegistrationMethods(registerEntityPacketListenersMethods, nameof(RegisterEntityPacketListenerEvent), entityPacketRetrievalSubscriptionDelegates);
+        CacheRegistrationMethods(clearRoutesMethods, nameof(ClearRouter), uniqueRetrievalSubscriptionDelegates);
     }
 
-    private void CacheRegistrationMethods(Dictionary<Type, MethodInfo> registrationMethods, string methodName)
+    /// <summary>
+    /// Creates generic method instances for each packet type listener to be registered into the <see cref="NetworkEntity"/>.
+    /// </summary>
+    private void CacheRegistrationMethods(
+        Dictionary<Type, MethodInfo> listenerRegistrationMethods,
+        string methodName,
+        List<PacketRetrievalDelegatePair> packetRetrievalDelegates)
     {
         MethodInfo registerPacketMethod = typeof(NetworkManager).GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Static)!;
+
         foreach ((Type packetType, Delegate @delegate) in packetRetrievalDelegates)
         {
             MethodInfo genericMethod = registerPacketMethod.MakeGenericMethod(packetType);
-            registrationMethods.Add(packetType, genericMethod);
+            listenerRegistrationMethods.TryAdd(packetType, genericMethod);
         }
     }
 
-    private void CachePacketArrivalMethods()
+    /// <summary>
+    /// Caches packet listener methods for all packet listener interfaces.
+    /// </summary>
+    private void CachePacketListenerMethods()
     {
-        CachePacketArrivalMethods(clientPacketArrivalMethods, typeof(IPacketListenerClient<>), nameof(IPacketListenerClient<INetworkEntity>.OnClientPacketArrived));
-        CachePacketArrivalMethods(serverPacketArrivalMethods, typeof(IPacketListenerServer<>), nameof(IPacketListenerServer<INetworkEntity>.OnServerPacketArrived));
+        CachePacketListenerMethods(clientBroadcastPacketListenerMethods, typeof(IPacketListenerClient<>), nameof(IPacketListenerClient<>.OnClientPacketArrived));
+        CachePacketListenerMethods(serverBroadcastPacketListenerMethods, typeof(IPacketListenerServer<>), nameof(IPacketListenerServer<>.OnServerPacketArrived));
+        CachePacketListenerMethods(clientEntityPacketListenerMethods, typeof(IPacketListenerClientEntity<>), nameof(IPacketListenerClientEntity<>.OnEntityClientPacketArrived));
+        CachePacketListenerMethods(serverEntityPacketListenerMethods, typeof(IPacketListenerServerEntity<>), nameof(IPacketListenerServerEntity<>.OnEntityServerPacketArrived));
     }
 
-    private static void CachePacketArrivalMethods(Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetArrivalMethods, Type listenerType, string packetArrivalMethodName)
+    /// <summary>
+    /// Discovers all types implementing a given packet listener interface and caches their methods.
+    /// </summary>
+    private static void CachePacketListenerMethods(
+        Dictionary<Type, Dictionary<Type, List<MethodInfo>>> packetListenerMethods,
+        Type listenerType,
+        string packetListenerMethodName)
     {
         foreach (Type listenerClass in GetGenericsWith(listenerType))
         {
-            Dictionary<Type, List<MethodInfo>> packetRouters = [];
-            packetArrivalMethods.Add(listenerClass, packetRouters);
+            Dictionary<Type, List<MethodInfo>> listenerMethodDictionary = [];
+            packetListenerMethods.Add(listenerClass, listenerMethodDictionary);
 
             foreach (Type packetListener in GetGenericInterfacesWith(listenerType, listenerClass))
             {
                 Type packetType = packetListener.GetGenericArguments().First();
 
-                List<MethodInfo> arrivalMethods = packetListener
-                    .GetMethods()
-                    .Where(m => m.Name == packetArrivalMethodName)
-                    .ToList();
+                List<MethodInfo> listenerMethods = [.. packetListener.GetMethods().Where(m => m.Name == packetListenerMethodName)];
 
-                packetRouters.Add(packetType, arrivalMethods);
+                listenerMethodDictionary.Add(packetType, listenerMethods);
             }
         }
     }
 
+    /// <summary>
+    /// Finds all types that implement a generic interface.
+    /// </summary>
     private static IEnumerable<Type> GetGenericsWith(Type type)
         => AppDomain.CurrentDomain
             .GetAssemblies()
             .SelectMany(a =>
                 a.GetTypes().Where(
                     t => t.GetInterfaces().Any(
-                        i => i.IsGenericType && i.GetGenericTypeDefinition() == type
-                    )
-                )
-            );
+                        i => i.IsGenericType && i.GetGenericTypeDefinition() == type)));
 
+    // Gets all generic interfaces of a specific definition on a type
     private static IEnumerable<Type> GetGenericInterfacesWith(Type interfaceType, Type type)
-        => type.GetInterfaces().Where(
-            i => i.IsGenericType && i.GetGenericTypeDefinition() == interfaceType
-        );
+        => type.GetInterfaces().Where(i => i.IsGenericType && i.GetGenericTypeDefinition() == interfaceType);
+
     #endregion
 
+    // Identifies whether packet routing is client-side or server-side
     private enum NetworkType { Client, Server }
+
+    private readonly record struct PacketRetrievalDelegatePair(Type PacketType, Delegate Delegate)
+    {
+        public static implicit operator (Type packetType, Delegate @delegate)(PacketRetrievalDelegatePair value) => (value.PacketType, value.Delegate);
+        public static implicit operator PacketRetrievalDelegatePair((Type packetType, Delegate @delegate) value) => new(value.packetType, value.@delegate);
+    }
 }

Engine.Systems/Tween/Tween.cs

@@ -27,8 +27,16 @@ internal class Tween : ITween
             field = value;
             switch (value)
             {
-                case TweenState.Completed: OnCompleted?.Invoke(this); OnEnded?.Invoke(this); break;
-                case TweenState.Cancelled: OnCancelled?.Invoke(this); OnEnded?.Invoke(this); break;
+                case TweenState.Completed:
+                    OnCompleted?.Invoke(this);
+                    if (State == TweenState.Completed)
+                        OnEnded?.Invoke(this);
+                    break;
+                case TweenState.Cancelled:
+                    OnCancelled?.Invoke(this);
+                    if (State == TweenState.Cancelled)
+                        OnEnded?.Invoke(this);
+                    break;
                 case TweenState.Paused: OnPaused?.Invoke(this); break;
                 case TweenState.Playing:
                     if (previousState == TweenState.Idle)

Engine.Systems/Tween/TweenExtensions.cs

@@ -4,35 +4,48 @@ namespace Engine.Systems.Tween;
 
 public static class TweenExtensions
 {
+    private static readonly System.Collections.Generic.Dictionary<ITween, int> loopDictionary = [];
+
     public static ITween Loop(this ITween tween, int count)
     {
-        Tween tweenConcrete = (Tween)tween;
-        int counter = count;
+        if (!loopDictionary.TryAdd(tween, count))
+            throw new($"Tween already has a loop in progress.");
 
-        tweenConcrete.OnCompleted.AddListener(_ =>
-        {
-            if (counter-- <= 0)
-                return;
-
-            tweenConcrete.Reset();
-            tweenConcrete.State = TweenState.Playing;
-        });
+        tween.OnCompleted.AddListener(looperDelegate);
+        tween.OnEnded.AddListener(looperEndDelegate);
 
         return tween;
     }
 
+    private static readonly Core.Event<ITween>.EventHandler looperEndDelegate = sender => loopDictionary.Remove(sender);
+    private static readonly Core.Event<ITween>.EventHandler looperDelegate = sender =>
+    {
+        int counter = loopDictionary[sender] = loopDictionary[sender] - 1;
+
+        if (counter <= 0)
+        {
+            loopDictionary.Remove(sender);
+            return;
+        }
+
+        Tween tweenConcrete = (Tween)sender;
+        tweenConcrete.Reset();
+        tweenConcrete.State = TweenState.Playing;
+    };
+
     public static ITween LoopInfinitely(this ITween tween)
     {
-        Tween tweenConcrete = (Tween)tween;
-        tweenConcrete.OnCompleted.AddListener(_ =>
-        {
-            tweenConcrete.Reset();
-            tweenConcrete.State = TweenState.Playing;
-        });
-
+        tween.OnCompleted.AddListener(repeaterDelegate);
         return tween;
     }
 
+    private static readonly Core.Event<ITween>.EventHandler repeaterDelegate = sender =>
+    {
+        Tween tweenConcrete = (Tween)sender;
+        tweenConcrete.Reset();
+        tweenConcrete.State = TweenState.Playing;
+    };
+
     public static ITween Ease(this ITween tween, IEasing easing)
     {
         Tween tweenConcrete = (Tween)tween;

Engine.Systems/Tween/TweenManager.cs

@@ -7,7 +7,7 @@ namespace Engine.Systems.Tween;
 
 public class TweenManager : Behaviour, IEnterUniverse, IExitUniverse, ITweenManager
 {
-    private CoroutineManager coroutineManager = null!;
+    private ICoroutineManager coroutineManager = null!;
 
     private readonly Dictionary<ITween, IEnumerator> runningCoroutines = [];
     private readonly Queue<Tween> pool = new();
@@ -75,7 +75,7 @@ public class TweenManager : Behaviour, IEnterUniverse, IExitUniverse, ITweenMana
 
     public void EnterUniverse(IUniverse universe)
     {
-        coroutineManager = universe.FindRequiredBehaviour<CoroutineManager>();
+        coroutineManager = universe.FindRequiredBehaviour<ICoroutineManager>();
     }
 
     public void ExitUniverse(IUniverse universe)

Engine.Systems/Tween/Yields/WaitForTweenCompleteCoroutineYield.cs

@@ -2,4 +2,4 @@ using Engine.Core;
 
 namespace Engine.Systems.Tween;
 
-public class WaitForTweenCompleteCoroutineYield(ITween tween) : CoroutineYield(() => tween.State == TweenState.Completed);
+public class WaitForTweenCompleteCoroutineYield(ITween tween) : WaitUntilYield(() => tween.State == TweenState.Completed);

Engine.Systems/Tween/Yields/WaitForTweenDoneCoroutineYield.cs

@@ -2,4 +2,4 @@ using Engine.Core;
 
 namespace Engine.Systems.Tween;
 
-public class WaitWhileTweenActiveCoroutineYield(ITween tween) : CoroutineYield(() => tween.State.CheckFlag(TweenState.Completed | TweenState.Cancelled));
+public class WaitForTweenDoneCoroutineYield(ITween tween) : WaitUntilYield(() => tween.State.CheckFlag(TweenState.Completed | TweenState.Cancelled));