feat: additive transform tweens added

Engine.Core/Abstract/IBehaviourController.cs

@@ -3,25 +3,10 @@ using System.Collections.Generic;
 namespace Syntriax.Engine.Core;
 
 /// <summary>
-/// Represents a controller for managing <see cref="IBehaviour"/>s and notify them accordingly about the engine's updates. Connected to an <see cref="IUniverseObject"/>.
+/// Represents a controller for managing <see cref="IBehaviour"/>s. Connected to an <see cref="IUniverseObject"/>.
 /// </summary>
 public interface IBehaviourController : IEntity, IHasUniverseObject, IEnumerable<IBehaviour>
 {
-    /// <summary>
-    /// Event triggered before the update of <see cref="IBehaviour"/>s.
-    /// </summary>
-    event PreUpdateEventHandler? OnPreUpdate;
-
-    /// <summary>
-    /// Event triggered during the update of <see cref="IBehaviour"/>s.
-    /// </summary>
-    event UpdateEventHandler? OnUpdate;
-
-    /// <summary>
-    /// Event triggered before the drawing phase.
-    /// </summary>
-    event PreDrawEventHandler? OnPreDraw;
-
     /// <summary>
     /// Event triggered when a <see cref="IBehaviour"/> is added to the <see cref="IBehaviourController"/>.
     /// </summary>
@@ -83,20 +68,6 @@ public interface IBehaviourController : IEntity, IHasUniverseObject, IEnumerable
     /// <param name="behaviour">The <see cref="IBehaviour"/> to remove.</param>
     void RemoveBehaviour<T>(T behaviour) where T : class, IBehaviour;
 
-    /// <summary>
-    /// Updates all <see cref="IBehaviour"/>s in the <see cref="IBehaviourController"/>.
-    /// </summary>
-    void Update();
-
-    /// <summary>
-    /// Performs pre-draw operations.
-    /// </summary>
-    void UpdatePreDraw();
-
-    delegate void PreUpdateEventHandler(IBehaviourController sender);
-    delegate void UpdateEventHandler(IBehaviourController sender);
-    delegate void PreDrawEventHandler(IBehaviourController sender);
     delegate void BehaviourAddedEventHandler(IBehaviourController sender, IBehaviour behaviourAdded);
     delegate void BehaviourRemovedEventHandler(IBehaviourController sender, IBehaviour behaviourRemoved);
-
 }

Engine.Core/Abstract/IUniverse.cs

@@ -18,9 +18,24 @@ public interface IUniverse : IEntity, IEnumerable<IUniverseObject>
     event UpdateEventHandler? OnUpdate;
 
     /// <summary>
-    /// Event triggered when <see cref="PreDraw"/> is called on the <see cref="IUniverse"/>.
+    /// Event triggered after <see cref="Update(UniverseTime)"/> is called on the <see cref="IUniverse"/>.
     /// </summary>
-    event PreDrawEventHandler? OnPreDraw;
+    event UpdateEventHandler? OnPostUpdate;
+
+    /// <summary>
+    /// Event triggered when <see cref="Draw"/> is about to be called called on the <see cref="IUniverse"/>.
+    /// </summary>
+    event DrawEventHandler? OnPreDraw;
+
+    /// <summary>
+    /// Event triggered when <see cref="Draw"/> is called on the <see cref="IUniverse"/>.
+    /// </summary>
+    event DrawEventHandler? OnDraw;
+
+    /// <summary>
+    /// Event triggered after <see cref="Draw"/> is called on the <see cref="IUniverse"/>.
+    /// </summary>
+    event DrawEventHandler? OnPostDraw;
 
     /// <summary>
     /// Event triggered when a <see cref="IUniverseObject"/> is registered to the <see cref="IUniverse"/>.
@@ -84,14 +99,14 @@ public interface IUniverse : IEntity, IEnumerable<IUniverseObject>
     void Update(UniverseTime universeTime);
 
     /// <summary>
-    /// Performs operations that should be done before the draw calls.
+    /// Performs operations that should be done to the draw.
     /// </summary>
-    void PreDraw();
+    void Draw();
 
     delegate void TimeScaleChangedEventHandler(IUniverse sender, float previousTimeScale);
 
     delegate void UpdateEventHandler(IUniverse sender, UniverseTime engineTime);
-    delegate void PreDrawEventHandler(IUniverse sender);
+    delegate void DrawEventHandler(IUniverse sender);
 
     delegate void UniverseObjectRegisteredEventHandler(IUniverse sender, IUniverseObject universeObjectRegistered);
     delegate void UniverseObjectUnRegisteredEventHandler(IUniverse sender, IUniverseObject universeObjectUnregistered);

Engine.Core/Behaviour.cs

@@ -1,9 +1,9 @@
 namespace Syntriax.Engine.Core;
 
-public abstract class Behaviour : BehaviourBase
+public abstract class Behaviour : BehaviourBase, IFirstFrameUpdate,
+    IPreUpdate, IUpdate, IPostUpdate,
+    IPreDraw, IDraw, IPostDraw
 {
-    private bool isInitializedThisFrame = false;
-
     protected IUniverse Universe => BehaviourController.UniverseObject.Universe;
     protected IUniverseObject UniverseObject => BehaviourController.UniverseObject;
 
@@ -20,11 +20,6 @@ public abstract class Behaviour : BehaviourBase
     protected virtual void OnInitialize() { }
     protected virtual void OnInitialize(IInitializable _)
     {
-        isInitializedThisFrame = true;
-
-        BehaviourController.OnPreUpdate += PreUpdate;
-        BehaviourController.OnPreDraw += PreDraw;
-        BehaviourController.OnUpdate += Update;
         BehaviourController.UniverseObject.OnEnteredUniverse += EnteredUniverse;
         BehaviourController.UniverseObject.OnExitedUniverse += ExitedUniverse;
 
@@ -37,9 +32,6 @@ public abstract class Behaviour : BehaviourBase
     protected virtual void OnFinalize() { }
     protected virtual void OnFinalize(IInitializable _)
     {
-        BehaviourController.OnPreUpdate -= PreUpdate;
-        BehaviourController.OnPreDraw -= PreDraw;
-        BehaviourController.OnUpdate -= Update;
         BehaviourController.UniverseObject.OnEnteredUniverse -= EnteredUniverse;
         BehaviourController.UniverseObject.OnExitedUniverse -= ExitedUniverse;
 
@@ -49,9 +41,16 @@ public abstract class Behaviour : BehaviourBase
             ExitedUniverse(UniverseObject, Universe);
     }
 
+    protected virtual void OnFirstActiveFrame() { }
+    void IFirstFrameUpdate.FirstActiveFrame()
+    {
+        Debug.Assert.AssertInitialized(this);
+        OnFirstActiveFrame();
+    }
+
     protected virtual void OnPreUpdatePreActiveCheck() { }
     protected virtual void OnPreUpdate() { }
-    protected virtual void PreUpdate(IBehaviourController _)
+    void IPreUpdate.PreUpdate()
     {
         Debug.Assert.AssertInitialized(this);
 
@@ -60,22 +59,12 @@ public abstract class Behaviour : BehaviourBase
         if (!IsActive)
             return;
 
-        if (isInitializedThisFrame)
-            FirstActiveFrame();
-
         OnPreUpdate();
     }
 
-    protected virtual void OnFirstActiveFrame() { }
-    protected virtual void FirstActiveFrame()
-    {
-        OnFirstActiveFrame();
-        isInitializedThisFrame = false;
-    }
-
     protected virtual void OnUpdatePreActiveCheck() { }
     protected virtual void OnUpdate() { }
-    protected virtual void Update(IBehaviourController _)
+    void IUpdate.Update()
     {
         Debug.Assert.AssertInitialized(this);
 
@@ -87,9 +76,23 @@ public abstract class Behaviour : BehaviourBase
         OnUpdate();
     }
 
+    protected virtual void OnPostUpdatePreActiveCheck() { }
+    protected virtual void OnPostUpdate() { }
+    void IPostUpdate.PostUpdate()
+    {
+        Debug.Assert.AssertInitialized(this);
+
+        OnPostUpdatePreActiveCheck();
+
+        if (!StateEnable.Enabled)
+            return;
+
+        OnPostUpdate();
+    }
+
     protected virtual void OnPreDrawPreActiveCheck() { }
     protected virtual void OnPreDraw() { }
-    protected virtual void PreDraw(IBehaviourController _)
+    void IPreDraw.PreDraw()
     {
         Debug.Assert.AssertInitialized(this);
 
@@ -101,6 +104,34 @@ public abstract class Behaviour : BehaviourBase
         OnPreDraw();
     }
 
+    protected virtual void OnDrawPreActiveCheck() { }
+    protected virtual void OnDraw() { }
+    void IDraw.Draw()
+    {
+        Debug.Assert.AssertInitialized(this);
+
+        OnDrawPreActiveCheck();
+
+        if (!StateEnable.Enabled)
+            return;
+
+        OnDraw();
+    }
+
+    protected virtual void OnPostDrawPreActiveCheck() { }
+    protected virtual void OnPostDraw() { }
+    void IPostDraw.PostDraw()
+    {
+        Debug.Assert.AssertInitialized(this);
+
+        OnPostDrawPreActiveCheck();
+
+        if (!StateEnable.Enabled)
+            return;
+
+        OnPostDraw();
+    }
+
     protected virtual void OnEnteredUniverse(IUniverse universe) { }
     protected virtual void EnteredUniverse(IUniverseObject sender, IUniverse universe) => OnEnteredUniverse(universe);
 

Engine.Core/Behaviour2D.cs

@@ -17,10 +17,6 @@ public abstract class Behaviour2D : Behaviour, IBehaviour2D
     }
 
     protected sealed override void OnUnassign(IAssignable assignable) => base.OnUnassign(assignable);
-    protected sealed override void PreUpdate(IBehaviourController behaviourController) => base.PreUpdate(behaviourController);
-    protected sealed override void FirstActiveFrame() => base.FirstActiveFrame();
-    protected sealed override void Update(IBehaviourController behaviourController) => base.Update(behaviourController);
-    protected sealed override void PreDraw(IBehaviourController behaviourController) => base.PreDraw(behaviourController);
     protected sealed override void EnteredUniverse(IUniverseObject sender, IUniverse universe) => base.EnteredUniverse(sender, universe);
     protected sealed override void ExitedUniverse(IUniverseObject sender, IUniverse universe) => base.ExitedUniverse(sender, universe);
 }

Engine.Core/BehaviourController.cs

@@ -8,10 +8,6 @@ namespace Syntriax.Engine.Core;
 [System.Diagnostics.DebuggerDisplay("Behaviour Count: {behaviours.Count}")]
 public class BehaviourController : BaseEntity, IBehaviourController
 {
-    public event IBehaviourController.PreUpdateEventHandler? OnPreUpdate = null;
-    public event IBehaviourController.UpdateEventHandler? OnUpdate = null;
-    public event IBehaviourController.PreDrawEventHandler? OnPreDraw = null;
-
     public event IBehaviourController.BehaviourAddedEventHandler? OnBehaviourAdded = null;
     public event IBehaviourController.BehaviourRemovedEventHandler? OnBehaviourRemoved = null;
     public event IHasUniverseObject.UniverseObjectAssignedEventHandler? OnUniverseObjectAssigned = null;
@@ -36,7 +32,10 @@ public class BehaviourController : BaseEntity, IBehaviourController
     }
 
     public T AddBehaviour<T>(params object?[]? args) where T : class, IBehaviour
-        => AddBehaviour(Factory.BehaviourFactory.Instantiate<T>(_universeObject, args));
+    {
+        T behaviour = Factory.BehaviourFactory.Instantiate<T>(args);
+        return AddBehaviour(behaviour);
+    }
 
     public T? GetBehaviour<T>()
     {
@@ -125,27 +124,6 @@ public class BehaviourController : BaseEntity, IBehaviourController
             behaviour.Finalize();
     }
 
-    public void Update()
-    {
-        Debug.Assert.AssertInitialized(this);
-
-        if (!UniverseObject.StateEnable.Enabled || !StateEnable.Enabled)
-            return;
-
-        OnPreUpdate?.InvokeSafe(this);
-        OnUpdate?.InvokeSafe(this);
-    }
-
-    public void UpdatePreDraw()
-    {
-        Debug.Assert.AssertInitialized(this);
-
-        if (!UniverseObject.StateEnable.Enabled || !StateEnable.Enabled)
-            return;
-
-        OnPreDraw?.InvokeSafe(this);
-    }
-
     public BehaviourController() { }
     public BehaviourController(IUniverseObject universeObject) => Assign(universeObject);
 

Engine.Core/Engine.Core.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>false</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>Syntriax.Engine.Core</RootNamespace>

Engine.Core/Exceptions/BehaviourNotFoundException.cs

@@ -1,9 +1,3 @@
-using System;
-
 namespace Syntriax.Engine.Core.Exceptions;
 
-public class BehaviourNotFoundException(string? message) : Exception(message)
+public class BehaviourNotFoundException(string? message) : NotFoundException(message);
-{
-    public static NotAssignedException FromType<TBehaviour>()
-        => new($"{typeof(TBehaviour).FullName} was not found");
-}

Engine.Core/Exceptions/NotFoundException.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace Syntriax.Engine.Core.Exceptions;
+
+public class NotFoundException(string? message) : Exception(message)
+{
+    public static NotAssignedException FromType<T>()
+        => new($"{typeof(T).FullName} was not found");
+}

Engine.Core/Exceptions/UniverseObjectNotFoundException.cs

@@ -1,9 +1,3 @@
-using System;
-
 namespace Syntriax.Engine.Core.Exceptions;
 
-public class UniverseObjectNotFoundException(string? message) : Exception(message)
+public class UniverseObjectNotFoundException(string? message) : NotFoundException(message);
-{
-    public static NotAssignedException FromType<TUniverseObject>()
-        => new($"{typeof(TUniverseObject).FullName} was not found");
-}

Engine.Core/Extensions/BehaviourControllerExtensions.cs

@@ -1,3 +1,4 @@
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 
 using Syntriax.Engine.Core.Exceptions;
@@ -38,6 +39,19 @@ public static class BehaviourControllerExtensions
     public static T GetOrAddBehaviour<T>(this IBehaviourController behaviourController, params object?[]? args) where T : class, IBehaviour
         => behaviourController.GetBehaviour<T>() ?? behaviourController.AddBehaviour<T>(args);
 
+    /// <summary>
+    /// Gets an existing <see cref="IBehaviour"/> of the specified type, or adds and returns the fallback type if it doesn't exist.
+    /// </summary>
+    /// <typeparam name="TOriginal">The type of <see cref="IBehaviour"/> to get.</typeparam>
+    /// <typeparam name="TFallback">The type of <see cref="IBehaviour"/> to add. It must be assignable from <typeparamref name="TOriginal"/></typeparam>
+    /// <param name="behaviourController">The <see cref="IBehaviourController"/> to search in.</param>
+    /// <param name="args">Optional arguments to pass to the constructor of the <see cref="IBehaviour"/> if a new one is added.</param>
+    /// <returns>The existing or newly added <see cref="IBehaviour"/> of the specified type.</returns>
+    public static TOriginal GetOrAddBehaviour<TOriginal, TFallback>(this IBehaviourController behaviourController, params object?[]? args)
+            where TOriginal : class
+            where TFallback : class, IBehaviour, TOriginal
+        => behaviourController.GetBehaviour<TOriginal>() ?? behaviourController.AddBehaviour<TFallback>(args);
+
     /// <summary>
     /// Tries to get a <see cref="IBehaviour"/> of the specified type in it's <see cref="IUniverseObject"/>'s parents recursively.
     /// </summary>
@@ -81,6 +95,27 @@ public static class BehaviourControllerExtensions
     public static T GetRequiredBehaviourInParent<T>(this IBehaviourController behaviourController) where T : class
         => behaviourController.GetBehaviourInParent<T>() ?? throw new BehaviourNotFoundException($"{behaviourController.UniverseObject.Name}'s {nameof(IBehaviourController)} does not contain any {typeof(T).FullName} on any parent");
 
+    /// <summary>
+    /// Gets all <see cref="IBehaviour"/>s of the specified type in it's <see cref="IUniverseObject"/>'s parents recursively and stores them in the provided list.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/>s to get.</typeparam>
+    /// <param name="behavioursInParent">The list to store the <see cref="IBehaviour"/>s.</param>
+    public static void GetBehavioursInParent<T>(this IBehaviourController behaviourController, IList<T> behavioursInParent) where T : class
+    {
+        IBehaviourController? controller = behaviourController;
+        List<T> cache = [];
+        behavioursInParent.Clear();
+
+        while (controller is not null)
+        {
+            controller.GetBehaviours(cache);
+            foreach (T behaviour in cache)
+                behavioursInParent.Add(behaviour);
+
+            controller = controller.UniverseObject.Parent?.BehaviourController;
+        }
+    }
+
     /// <summary>
     /// Tries to get a <see cref="IBehaviour"/> of the specified type in it's <see cref="IUniverseObject"/>'s children recursively.
     /// </summary>
@@ -120,4 +155,28 @@ public static class BehaviourControllerExtensions
     /// <returns>The <see cref="IBehaviour"/> of the specified type if found; otherwise, throws <see cref="BehaviourNotFoundException"/>.</returns>
     public static T GetRequiredBehaviourInChildren<T>(this IBehaviourController behaviourController) where T : class
         => behaviourController.GetBehaviourInChildren<T>() ?? throw new BehaviourNotFoundException($"{behaviourController.UniverseObject.Name}'s {nameof(IBehaviourController)} does not contain any {typeof(T).FullName} on any children ");
+
+    /// <summary>
+    /// Gets all <see cref="IBehaviour"/>s of the specified type in it's <see cref="IUniverseObject"/>'s children recursively and stores them in the provided list.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/>s to get.</typeparam>
+    /// <param name="behavioursInChildren">The list to store the <see cref="IBehaviour"/>s.</param>
+    public static void GetBehavioursInChildren<T>(this IBehaviourController behaviourController, IList<T> behavioursInChildren) where T : class
+    {
+        List<T> cache = [];
+        behavioursInChildren.Clear();
+
+        TraverseChildrenForBehaviour(behaviourController.UniverseObject, behavioursInChildren, cache);
+    }
+
+    private static void TraverseChildrenForBehaviour<T>(IUniverseObject universeObject, IList<T> behaviours, IList<T> cache) where T : class
+    {
+        universeObject.BehaviourController.GetBehaviours(cache);
+
+        foreach (T behaviour in cache)
+            behaviours.Add(behaviour);
+
+        foreach (IUniverseObject child in universeObject)
+            TraverseChildrenForBehaviour(child, behaviours, cache);
+    }
 }

Engine.Core/Extensions/BehaviourExtensions.cs

@@ -1,34 +0,0 @@
-using System.Collections.Generic;
-using System.Diagnostics.CodeAnalysis;
-
-namespace Syntriax.Engine.Core;
-
-public static class BehaviourExtensions
-{
-    public static T? FindBehaviour<T>(this IEnumerable<IUniverseObject> universeObjects) where T : class
-    {
-        foreach (IUniverseObject universeObject in universeObjects)
-            if (universeObject.BehaviourController.GetBehaviour<T>() is T behaviour)
-                return behaviour;
-
-        return default;
-    }
-
-    public static bool TryFindBehaviour<T>(this IEnumerable<IUniverseObject> universeObjects, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
-    {
-        behaviour = FindBehaviour<T>(universeObjects);
-        return behaviour is not null;
-    }
-
-    public static void FindBehaviours<T>(this IEnumerable<IUniverseObject> universeObjects, List<T> behaviours) where T : class
-    {
-        behaviours.Clear();
-        List<T> cache = [];
-
-        foreach (IUniverseObject universeObject in universeObjects)
-        {
-            universeObject.BehaviourController.GetBehaviours(cache);
-            behaviours.AddRange(cache);
-        }
-    }
-}

Engine.Core/Extensions/UniverseExtensions.cs

@@ -7,9 +7,30 @@ public static class UniverseExtensions
     public static IUniverseObject InstantiateUniverseObject(this IUniverse universe, params object?[]? args)
         => universe.InstantiateUniverseObject<UniverseObject>(args);
 
+    /// <summary>
+    /// Searches through all <see cref="IUniverseObject"/>s to find the specified instance of the type.
+    /// </summary>
+    /// <typeparam name="T">Type to be searched through the <see cref="IUniverse"/>.</typeparam>
+    /// <returns>The specified type if found; otherwise, throws <see cref="UniverseObjectNotFoundException"/>.</returns>
     public static T GetRequiredUniverseObject<T>(this IUniverse universe) where T : class
         => universe.GetUniverseObject<T>() ?? throw new UniverseObjectNotFoundException($"{universe.GetType().FullName}({universe.Id}) does not contain any {nameof(IUniverseObject)} object of type {typeof(T).FullName}");
 
+    /// <summary>
+    /// Searches through all <see cref="IBehaviours"/>s to find the specified instance of the type.
+    /// </summary>
+    /// <typeparam name="T">Type to be searched through the <see cref="IUniverse"/>.</typeparam>
+    /// <returns>The specified type if found; otherwise, throws <see cref="BehaviourNotFoundException"/>.</returns>
     public static T FindRequiredBehaviour<T>(this IUniverse universe) where T : class
         => universe.FindBehaviour<T>() ?? throw new BehaviourNotFoundException($"{universe.GetType().FullName}({universe.Id}) does not contain any {nameof(IUniverseObject)} with {nameof(IBehaviour)} of type {typeof(T).FullName}");
+
+    /// <summary>
+    /// Searches through all <see cref="IUniverseObject"/>s and <see cref="IBehaviours"/>s to find the specified instance of the type.
+    /// </summary>
+    /// <remarks>
+    /// WARNING: This is more expensive compared to <see cref="GetRequiredUniverseObject{T}(IUniverse)"/> or <see cref="FindRequiredBehaviour{T}(IUniverse)"/> as it combines the two. If you know whether the type is either a type that gets implemented on an <see cref="IBehaviour"/> or <see cref="IUniverseObject"/> use the method appropriate for it for performance.
+    /// </remarks>
+    /// <typeparam name="T">Type to be searched through the <see cref="IUniverse"/>.</typeparam>
+    /// <returns>The specified type if found; otherwise, throws <see cref="NotFoundException"/>.</returns>
+    public static T FindRequired<T>(this IUniverse universe) where T : class
+        => universe.Find<T>() ?? throw new NotFoundException($"{universe.GetType().FullName}({universe.Id}) does not contain any {nameof(IUniverseObject)} or {nameof(IBehaviour)} of type {typeof(T).FullName}");
 }

Engine.Core/Extensions/UniverseObjectExtensions.cs

@@ -1,6 +1,8 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 
+using Syntriax.Engine.Core.Exceptions;
+
 namespace Syntriax.Engine.Core;
 
 public static class UniverseObjectExtensions
@@ -14,6 +16,13 @@ public static class UniverseObjectExtensions
         return universeObject;
     }
 
+    #region Universe Object Search
+    /// <summary>
+    /// Gets a <see cref="IUniverseObject"/> of the specified type.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObjects">The <see cref="IUniverseObject"/>s to search.</param>
+    /// <returns>The first found <see cref="IUniverseObject"/> of the specified type; otherwise, null.</returns>
     public static T? GetUniverseObject<T>(this IEnumerable<IUniverseObject> universeObjects) where T : class
     {
         foreach (IUniverseObject universeObject in universeObjects)
@@ -23,17 +32,224 @@ public static class UniverseObjectExtensions
         return default;
     }
 
-    public static bool TryGetUniverseObject<T>(this IEnumerable<IUniverseObject> universeObjects, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
+    /// <summary>
+    /// Tries to get a <see cref="IUniverseObject"/> of the specified type.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObjects">The <see cref="IUniverseObject"/>s to search.</param>
+    /// <returns><see cref="true"/> if a <see cref="IUniverseObject"/> of the specified type was found in the universe objects; otherwise, <see cref="false"/>.</returns>
+    public static bool TryGetUniverseObject<T>(this IEnumerable<IUniverseObject> universeObjects, [NotNullWhen(returnValue: true)] out T? universeObject) where T : class
     {
-        behaviour = GetUniverseObject<T>(universeObjects);
+        universeObject = GetUniverseObject<T>(universeObjects);
+        return universeObject is not null;
+    }
+
+    /// <summary>
+    /// Searches through the provided <see cref="IUniverseObject"/>s to collect a list of <see cref="IUniverseObject"/>s of the specified type.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObject">The <see cref="IUniverseObject"/> to search.</param>
+    /// <returns>The found <see cref="IUniverseObject"/>s of the specified types</returns>
+    public static void GetUniverseObjects<T>(this IEnumerable<IUniverseObject> universeObjects, IList<T> foundUniverseObjects) where T : class
+    {
+        foundUniverseObjects.Clear();
+
+        foreach (IUniverseObject universeObject in universeObjects)
+            if (universeObject is T @object)
+                foundUniverseObjects.Add(@object);
+    }
+    #endregion
+
+    #region Universe Object Search In Parent
+    /// <summary>
+    /// Tries to get a <see cref="IUniverseObject"/> of the specified type in it's parents recursively.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="behaviour">When this method returns, contains the <see cref="IUniverseObject"/> of the specified type, if found; otherwise, null.</param>
+    /// <returns><see cref="true"/> if a <see cref="IUniverseObject"/> of the specified type was found in the parent universe objects; otherwise, <see cref="false"/>.</returns>
+    public static bool TryGetUniverseObjectInParent<T>(this IUniverseObject universeObject, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
+    {
+        behaviour = GetUniverseObjectInParent<T>(universeObject);
         return behaviour is not null;
     }
 
-    public static void GetUniverseObjects<T>(this IEnumerable<IUniverseObject> universeObjects, List<T> behaviours) where T : class
+    /// <summary>
+    /// Gets a <see cref="IUniverseObject"/> of the specified type in it's parents recursively.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObject">The <see cref="IUniverseObject"/> to start searching from.</param>
+    /// <returns>The <see cref="IUniverseObject"/> of the specified type if found; otherwise, null.</returns>
+    public static T? GetUniverseObjectInParent<T>(this IUniverseObject universeObject) where T : class
+    {
+        if (universeObject.GetUniverseObject<T>() is T localUniverseObject)
+            return localUniverseObject;
+
+        IUniverseObject? parent = universeObject;
+
+        while (parent is not null)
+        {
+            if (parent is T behaviour)
+                return behaviour;
+
+            parent = universeObject.Parent;
+        }
+
+        return default;
+    }
+
+    /// <summary>
+    /// Gets a <see cref="IUniverseObject"/> of the specified type in the parents recursively. Throws an error if not found.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObject">The <see cref="IUniverseObject"/> to start searching from.</param>
+    /// <returns>The <see cref="IUniverseObject"/> of the specified type if found; otherwise, throws <see cref="UniverseObjectNotFoundException"/>.</returns>
+    public static T GetRequiredUniverseObjectInParent<T>(this IUniverseObject universeObject) where T : class
+        => universeObject.GetUniverseObjectInParent<T>() ?? throw new UniverseObjectNotFoundException($"{universeObject.Name}'s {nameof(IUniverseObject)} does not contain any {typeof(T).FullName} on any parent ");
+
+    #endregion
+
+    #region Universe Object Search In Children
+    /// <summary>
+    /// Tries to get a <see cref="IUniverseObject"/> of the specified type in it's children recursively.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="behaviour">When this method returns, contains the <see cref="IUniverseObject"/> of the specified type, if found; otherwise, null.</param>
+    /// <returns><see cref="true"/> if a <see cref="IUniverseObject"/> of the specified type was found in the child universe objects; otherwise, <see cref="false"/>.</returns>
+    public static bool TryGetUniverseObjectInChildren<T>(this IUniverseObject universeObject, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
+    {
+        behaviour = GetUniverseObjectInChildren<T>(universeObject);
+        return behaviour is not null;
+    }
+
+    /// <summary>
+    /// Gets a <see cref="IUniverseObject"/> of the specified type in it's children recursively.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObject">The <see cref="IUniverseObject"/> to start searching from.</param>
+    /// <returns>The <see cref="IUniverseObject"/> of the specified type if found; otherwise, null.</returns>
+    public static T? GetUniverseObjectInChildren<T>(this IUniverseObject universeObject) where T : class
+    {
+        if (universeObject.GetUniverseObject<T>() is T localUniverseObject)
+            return localUniverseObject;
+
+        foreach (IUniverseObject child in universeObject)
+            if (GetUniverseObjectInChildren<T>(child) is T behaviour)
+                return behaviour;
+
+        return default;
+    }
+
+    /// <summary>
+    /// Gets a <see cref="IUniverseObject"/> of the specified type in the children recursively. Throws an error if not found.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IUniverseObject"/> to get.</typeparam>
+    /// <param name="universeObject">The <see cref="IUniverseObject"/> to start searching from.</param>
+    /// <returns>The <see cref="IUniverseObject"/> of the specified type if found; otherwise, throws <see cref="UniverseObjectNotFoundException"/>.</returns>
+    public static T GetRequiredUniverseObjectInChildren<T>(this IUniverseObject universeObject) where T : class
+        => universeObject.GetUniverseObjectInChildren<T>() ?? throw new UniverseObjectNotFoundException($"{universeObject.Name}'s {nameof(IUniverseObject)} does not contain any {typeof(T).FullName} on any children ");
+    #endregion
+
+    #region Behaviour Search
+    /// <summary>
+    /// Finds a <see cref="IBehaviour"/> of the specified type in the provided <see cref="IUniverseObject"/>s.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to find.</typeparam>
+    /// <returns>The first found <see cref="IBehaviour"/> of the specified type; otherwise, null.</returns>
+    public static T? FindBehaviour<T>(this IEnumerable<IUniverseObject> universeObjects) where T : class
+    {
+        foreach (IUniverseObject universeObject in universeObjects)
+            if (universeObject.BehaviourController.GetBehaviour<T>() is T behaviour)
+                return behaviour;
+
+        return default;
+    }
+
+    /// <summary>
+    /// Tries to find a <see cref="IBehaviour"/> of the specified type in the provided <see cref="IUniverseObject"/>s.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to find.</typeparam>
+    /// <param name="behaviour">When this method returns, contains the <see cref="IUniverseObject"/> of the specified type, if found; otherwise, null.</param>
+    /// <returns><see cref="true"/> if a <see cref="IBehaviour"/> of the specified type was found in the provided <see cref="IUniverseObject"/>s; otherwise, <see cref="false"/>.</returns>
+    public static bool TryFindBehaviour<T>(this IEnumerable<IUniverseObject> universeObjects, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
+    {
+        behaviour = FindBehaviour<T>(universeObjects);
+        return behaviour is not null;
+    }
+
+    /// <summary>
+    /// Searches through the provided <see cref="IUniverseObject"/>s to collect a list of <see cref="IBehaviour"/>s of the specified type.
+    /// </summary>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to get.</typeparam>
+    /// <param name="universeObjects">The <see cref="IUniverseObject"/>s to search.</param>
+    public static void FindBehaviours<T>(this IEnumerable<IUniverseObject> universeObjects, IList<T> behaviours) where T : class
     {
         behaviours.Clear();
+        List<T> cache = [];
+
         foreach (IUniverseObject universeObject in universeObjects)
-            if (universeObject is T @object)
+        {
-                behaviours.Add(@object);
+            universeObject.BehaviourController.GetBehaviours(cache);
+            foreach (T behaviour in cache)
+                behaviours.Add(behaviour);
+        }
     }
+    #endregion
+
+    #region General Search
+    /// <summary>
+    /// Finds an object of the specified type in the provided <see cref="IUniverseObject"/>s and their <see cref="IBehaviour"/>s.
+    /// </summary>
+    /// <remarks>
+    /// WARNING: This is more expensive compared to <see cref="GetUniverseObject{T}(IEnumerable{IUniverseObject})"/> or <see cref="FindBehaviour{T}(IEnumerable{IUniverseObject})"/> as it combines the two. If you know whether the type is either a type that gets implemented on an <see cref="IBehaviour"/> or <see cref="IUniverseObject"/> use the method appropriate for it for performance.
+    /// </remarks>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to find.</typeparam>
+    /// <returns>The first found instance of the specified type; otherwise, null.</returns>
+    public static T? Find<T>(this IEnumerable<IUniverseObject> universeObjects) where T : class
+    {
+        if (universeObjects.GetUniverseObject<T>() is T foundUniverseObject)
+            return foundUniverseObject;
+
+        if (universeObjects.FindBehaviour<T>() is T foundBehaviour)
+            return foundBehaviour;
+
+        return null;
+    }
+
+    /// <summary>
+    /// Tries to find an object of the specified type in the provided <see cref="IUniverseObject"/>s and their <see cref="IBehaviour"/>s.
+    /// </summary>
+    /// <remarks>
+    /// WARNING: This is more expensive compared to <see cref="TryGetUniverseObject{T}(IEnumerable{IUniverseObject}, out T?)"/> or <see cref="TryFindBehaviour{T}(IEnumerable{IUniverseObject}, out T?)"/> as it combines the two. If you know whether the type is either a type that gets implemented on an <see cref="IBehaviour"/> or <see cref="IUniverseObject"/> use the method appropriate for it for performance.
+    /// </remarks>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to find.</typeparam>
+    /// <param name="behaviour">When this method returns, contains the <see cref="IUniverseObject"/> of the specified type, if found; otherwise, null.</param>
+    /// <returns><see cref="true"/> if an object of the specified type was found in the provided <see cref="IUniverseObject"/>s; otherwise, <see cref="false"/>.</returns>
+    public static bool TryFind<T>(this IEnumerable<IUniverseObject> universeObjects, [NotNullWhen(returnValue: true)] out T? behaviour) where T : class
+    {
+        behaviour = Find<T>(universeObjects);
+        return behaviour is not null;
+    }
+
+    /// <summary>
+    /// Searches through the provided <see cref="IUniverseObject"/>s and their <see cref="IBehaviour"/>s to collect a list of the specified type.
+    /// </summary>
+    /// <remarks>
+    /// WARNING: This is more expensive compared to <see cref="GetUniverseObjects{T}(IEnumerable{IUniverseObject}, IList{T})"/> or <see cref="FindBehaviours{T}(IEnumerable{IUniverseObject}, IList{T})"/> as it combines the two. If you know whether the type is either a type that gets implemented on an <see cref="IBehaviour"/> or <see cref="IUniverseObject"/> use the method appropriate for it for performance.
+    /// </remarks>
+    /// <typeparam name="T">The type of <see cref="IBehaviour"/> to get.</typeparam>
+    /// <param name="instances">List of objects found wit the specified type.</param>
+    /// <param name="universeObjects">The <see cref="IUniverseObject"/>s to search.</param>
+    public static void Find<T>(this IEnumerable<IUniverseObject> universeObjects, IList<T> instances) where T : class
+    {
+        instances.Clear();
+        List<T> cache = [];
+
+        foreach (IUniverseObject universeObject in universeObjects)
+        {
+            universeObject.Find(cache);
+            foreach (T behaviour in cache)
+                instances.Add(behaviour);
+        }
+    }
+    #endregion
 }

Engine.Core/Factory/BehaviourFactory.cs

@@ -4,10 +4,10 @@ namespace Syntriax.Engine.Core.Factory;
 
 public class BehaviourFactory
 {
-    public static T Instantiate<T>(IUniverseObject universeObject, params object?[]? args) where T : class, IBehaviour
+    public static T Instantiate<T>(params object?[]? args) where T : class, IBehaviour
-        => Instantiate<T>(universeObject, stateEnable: null, args);
+        => Instantiate<T>(stateEnable: null, args);
 
-    public static T Instantiate<T>(IUniverseObject universeObject, IStateEnable? stateEnable, params object?[]? args)
+    public static T Instantiate<T>(IStateEnable? stateEnable, params object?[]? args)
         where T : class, IBehaviour
     {
         T behaviour = TypeFactory.Get<T>(args);
@@ -18,8 +18,6 @@ public class BehaviourFactory
 
         if (!behaviour.Assign(stateEnable))
             throw AssignFailedException.From(behaviour, stateEnable);
-        if (!behaviour.Assign(universeObject.BehaviourController))
-            throw AssignFailedException.From(behaviour, universeObject.BehaviourController);
 
         return behaviour;
     }

Engine.Core/Systems/Abstract/IDraw.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified when the draw phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IDraw : IBehaviour
+{
+    /// <summary>
+    /// Calls draw logic for the <see cref="IBehaviour"/> to be displayed visually.
+    /// </summary>
+    void Draw();
+}

Engine.Core/Systems/Abstract/IFirstFrameUpdate.cs

@@ -0,0 +1,6 @@
+namespace Syntriax.Engine.Core;
+
+public interface IFirstFrameUpdate : IBehaviour
+{
+    void FirstActiveFrame();
+}

Engine.Core/Systems/Abstract/IPostDraw.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified after the draw phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IPostDraw : IBehaviour
+{
+    /// <summary>
+    /// Updates the state of the <see cref="IBehaviour"/> after the main draw phase happens.
+    /// </summary>
+    void PostDraw();
+}

Engine.Core/Systems/Abstract/IPostUpdate.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified after the update phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IPostUpdate : IBehaviour
+{
+    /// <summary>
+    /// Updates the state of the <see cref="IBehaviour"/> after the main update phase happens.
+    /// </summary>
+    void PostUpdate();
+}

Engine.Core/Systems/Abstract/IPreDraw.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified before the draw phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IPreDraw : IBehaviour
+{
+    /// <summary>
+    /// Updates the state of the <see cref="IBehaviour"/> before the main draw phase happens.
+    /// </summary>
+    void PreDraw();
+}

Engine.Core/Systems/Abstract/IPreUpdate.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified before the update phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IPreUpdate : IBehaviour
+{
+    /// <summary>
+    /// Updates the state of the <see cref="IBehaviour"/> before the main update phase happens.
+    /// </summary>
+    void PreUpdate();
+}

Engine.Core/Systems/Abstract/IUpdate.cs

@@ -0,0 +1,12 @@
+namespace Syntriax.Engine.Core;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> to be notified when the update phase of the <see cref="IUniverse"/> occurs.
+/// </summary>
+public interface IUpdate : IBehaviour
+{
+    /// <summary>
+    /// Updates the state of the <see cref="IBehaviour"/>.
+    /// </summary>
+    void Update();
+}

Engine.Core/Systems/DrawManager.cs

@@ -0,0 +1,51 @@
+
+namespace Syntriax.Engine.Core;
+
+public class DrawManager : UniverseObject
+{
+    private static System.Comparison<IBehaviour> SortByPriority() => (x, y) => y.Priority.CompareTo(x.Priority);
+
+    private readonly ActiveBehaviourCollectorSorted<IPreDraw> preDrawEntities = new() { SortBy = SortByPriority() };
+    private readonly ActiveBehaviourCollectorSorted<IDraw> drawEntities = new() { SortBy = SortByPriority() };
+    private readonly ActiveBehaviourCollectorSorted<IPostDraw> postDrawEntities = new() { SortBy = SortByPriority() };
+
+    private void OnPreDraw(IUniverse sender)
+    {
+        for (int i = preDrawEntities.Behaviours.Count - 1; i >= 0; i--)
+            preDrawEntities.Behaviours[i].PreDraw();
+    }
+
+    private void OnDraw(IUniverse sender)
+    {
+        for (int i = drawEntities.Behaviours.Count - 1; i >= 0; i--)
+            drawEntities.Behaviours[i].Draw();
+    }
+
+    private void OnPostDraw(IUniverse sender)
+    {
+        for (int i = postDrawEntities.Behaviours.Count - 1; i >= 0; i--)
+            postDrawEntities.Behaviours[i].PostDraw();
+    }
+
+    protected override void OnEnteringUniverse(IUniverse universe)
+    {
+        preDrawEntities.Assign(universe);
+        drawEntities.Assign(universe);
+        postDrawEntities.Assign(universe);
+
+        universe.OnPreDraw += OnPreDraw;
+        universe.OnDraw += OnDraw;
+        universe.OnPostDraw += OnPostDraw;
+    }
+
+    protected override void OnExitingUniverse(IUniverse universe)
+    {
+        preDrawEntities.Unassign();
+        drawEntities.Unassign();
+        postDrawEntities.Unassign();
+
+        universe.OnPreDraw -= OnPreDraw;
+        universe.OnDraw -= OnDraw;
+        universe.OnPostDraw -= OnPostDraw;
+    }
+}

Engine.Core/Systems/UpdateManager.cs

@@ -0,0 +1,74 @@
+
+using System.Collections.Generic;
+
+namespace Syntriax.Engine.Core;
+
+public class UpdateManager : UniverseObject
+{
+    private static System.Comparison<IBehaviour> SortByPriority() => (x, y) => y.Priority.CompareTo(x.Priority);
+
+    private readonly ActiveBehaviourCollectorSorted<IFirstFrameUpdate> firstFrameUpdates = new() { SortBy = SortByPriority() };
+    private readonly ActiveBehaviourCollectorSorted<IPreUpdate> preUpdateEntities = new() { SortBy = SortByPriority() };
+    private readonly ActiveBehaviourCollectorSorted<IUpdate> updateEntities = new() { SortBy = SortByPriority() };
+    private readonly ActiveBehaviourCollectorSorted<IPostUpdate> postUpdateEntities = new() { SortBy = SortByPriority() };
+
+    private readonly List<IFirstFrameUpdate> toCallFirstFrameUpdates = [];
+
+    protected override void OnEnteringUniverse(IUniverse universe)
+    {
+        firstFrameUpdates.Assign(universe);
+        preUpdateEntities.Assign(universe);
+        updateEntities.Assign(universe);
+        postUpdateEntities.Assign(universe);
+
+        universe.OnPreUpdate += OnPreUpdate;
+        universe.OnUpdate += OnUpdate;
+        universe.OnPostUpdate += OnPostUpdate;
+    }
+
+    protected override void OnExitingUniverse(IUniverse universe)
+    {
+        firstFrameUpdates.Unassign();
+        preUpdateEntities.Unassign();
+        updateEntities.Unassign();
+        postUpdateEntities.Unassign();
+
+        universe.OnPreUpdate -= OnPreUpdate;
+        universe.OnUpdate -= OnUpdate;
+        universe.OnPostUpdate -= OnPostUpdate;
+    }
+
+    private void OnPreUpdate(IUniverse sender, UniverseTime engineTime)
+    {
+        for (int i = toCallFirstFrameUpdates.Count - 1; i >= 0; i--)
+        {
+            toCallFirstFrameUpdates[i].FirstActiveFrame();
+            toCallFirstFrameUpdates.RemoveAt(i);
+        }
+
+        for (int i = preUpdateEntities.Behaviours.Count - 1; i >= 0; i--)
+            preUpdateEntities.Behaviours[i].PreUpdate();
+    }
+
+    private void OnUpdate(IUniverse sender, UniverseTime engineTime)
+    {
+        for (int i = updateEntities.Behaviours.Count - 1; i >= 0; i--)
+            updateEntities.Behaviours[i].Update();
+    }
+
+    private void OnPostUpdate(IUniverse sender, UniverseTime engineTime)
+    {
+        for (int i = postUpdateEntities.Behaviours.Count - 1; i >= 0; i--)
+            postUpdateEntities.Behaviours[i].PostUpdate();
+    }
+
+    private void OnFirstFrameCollected(IBehaviourCollector<IFirstFrameUpdate> sender, IFirstFrameUpdate behaviourCollected)
+    {
+        toCallFirstFrameUpdates.Add(behaviourCollected);
+    }
+
+    public UpdateManager()
+    {
+        firstFrameUpdates.OnCollected += OnFirstFrameCollected;
+    }
+}

Engine.Core/Universe.cs

@@ -9,7 +9,10 @@ public class Universe : BaseEntity, IUniverse
 {
     public event IUniverse.UpdateEventHandler? OnPreUpdate = null;
     public event IUniverse.UpdateEventHandler? OnUpdate = null;
-    public event IUniverse.PreDrawEventHandler? OnPreDraw = null;
+    public event IUniverse.UpdateEventHandler? OnPostUpdate = null;
+    public event IUniverse.DrawEventHandler? OnPreDraw = null;
+    public event IUniverse.DrawEventHandler? OnDraw = null;
+    public event IUniverse.DrawEventHandler? OnPostDraw = null;
 
     public event IUniverse.UniverseObjectRegisteredEventHandler? OnUniverseObjectRegistered = null;
     public event IUniverse.UniverseObjectUnRegisteredEventHandler? OnUniverseObjectUnRegistered = null;
@@ -116,21 +119,17 @@ public class Universe : BaseEntity, IUniverse
         Time = new(TimeSpan.FromTicks((long)(Time.TimeSinceStart.Ticks + engineTime.DeltaSpan.Ticks * TimeScale)), TimeSpan.FromTicks((long)(engineTime.DeltaSpan.Ticks * TimeScale)));
 
         OnPreUpdate?.InvokeSafe(this, Time);
-
-        for (int i = 0; i < UniverseObjects.Count; i++)
-            UniverseObjects[i].BehaviourController.Update();
-
         OnUpdate?.InvokeSafe(this, Time);
+        OnPostUpdate?.InvokeSafe(this, Time);
     }
 
-    public void PreDraw()
+    public void Draw()
     {
         Debug.Assert.AssertInitialized(this);
 
-        for (int i = 0; i < UniverseObjects.Count; i++)
-            UniverseObjects[i].BehaviourController.UpdatePreDraw();
-
         OnPreDraw?.InvokeSafe(this);
+        OnDraw?.InvokeSafe(this);
+        OnPostDraw?.InvokeSafe(this);
     }
 
     private void OnUniverseObjectFinalize(IInitializable initializable)

Engine.Physics2D/Abstract/IPhysicsEngine2D.cs

@@ -26,6 +26,13 @@ public interface IPhysicsEngine2D
     /// <param name="deltaTime">The time step.</param>
     void Step(float deltaTime);
 
+    /// <summary>
+    /// Advances the physics simulation by the specified time on a single <see cref="IRigidBody2D"/>.
+    /// </summary>
+    /// <param name="rigidBody">The <see cref="IRigidBody2D"/> to be progressed individually.</param>
+    /// <param name="deltaTime">The time step.</param>
+    void StepIndividual(IRigidBody2D rigidBody, float deltaTime);
+
     delegate void PhysicsIterationEventHandler(IPhysicsEngine2D sender, float iterationDeltaTime);
     delegate void PhysicsStepEventHandler(IPhysicsEngine2D sender, float stepDeltaTime);
 }

Engine.Physics2D/Abstract/Updates/IPostPhysicsUpdate.cs

@@ -0,0 +1,15 @@
+using Syntriax.Engine.Core;
+
+namespace Syntriax.Engine.Physics2D;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> that listens to the phase after the physics simulation phase.
+/// </summary>
+public interface IPostPhysicsUpdate : IBehaviour
+{
+    /// <summary>
+    /// Execute logic that should occur after the physics simulation has been updated.
+    /// </summary>
+    /// <param name="delta">The time elapsed since the last physics update, typically in seconds.</param>
+    void PostPhysicsUpdate(float delta);
+}

Engine.Physics2D/Abstract/Updates/IPrePhysicsUpdate.cs

@@ -0,0 +1,15 @@
+using Syntriax.Engine.Core;
+
+namespace Syntriax.Engine.Physics2D;
+
+/// <summary>
+/// Represents a <see cref="IBehaviour"/> that listens to the phase before the physics simulation phase.
+/// </summary>
+public interface IPrePhysicsUpdate : IBehaviour
+{
+    /// <summary>
+    /// Execute logic that should occur before the physics simulation is updated.
+    /// </summary>
+    /// <param name="delta">The time elapsed since the last physics update, typically in seconds.</param>
+    void PrePhysicsUpdate(float delta);
+}

Engine.Physics2D/Engine.Physics2D.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>Syntriax.Engine.Physics2D</RootNamespace>

Engine.Physics2D/PhysicsEngine2D.cs

@@ -14,9 +14,12 @@ public class PhysicsEngine2D : UniverseObject, IPhysicsEngine2D
     protected readonly ICollisionDetector2D collisionDetector = null!;
     protected readonly ICollisionResolver2D collisionResolver = null!;
 
+    private static System.Comparison<IBehaviour> SortByPriority() => (x, y) => y.Priority.CompareTo(x.Priority);
+    protected ActiveBehaviourCollectorSorted<IPrePhysicsUpdate> physicsPreUpdateCollector = new() { SortBy = SortByPriority() };
+    protected ActiveBehaviourCollectorSorted<IPhysicsUpdate> physicsUpdateCollector = new() { SortBy = SortByPriority() };
+    protected ActiveBehaviourCollectorSorted<IPostPhysicsUpdate> physicsPostUpdateCollector = new() { SortBy = SortByPriority() };
     protected BehaviourCollector<IRigidBody2D> rigidBodyCollector = new();
     protected BehaviourCollector<ICollider2D> colliderCollector = new();
-    protected BehaviourCollector<IPhysicsUpdate> physicsUpdateCollector = new();
 
     public int IterationPerStep { get => _iterationPerStep; set => _iterationPerStep = value < 1 ? 1 : value; }
     public float IterationPeriod { get => _iterationPeriod; set => _iterationPeriod = value.Max(0.0001f); }
@@ -25,6 +28,12 @@ public class PhysicsEngine2D : UniverseObject, IPhysicsEngine2D
     {
         float intervalDeltaTime = deltaTime / IterationPerStep;
 
+        foreach (IPrePhysicsUpdate physicsPreUpdate in physicsPreUpdateCollector)
+            physicsPreUpdate.PrePhysicsUpdate(deltaTime);
+
+        foreach (IPhysicsUpdate physicsUpdate in physicsUpdateCollector)
+            physicsUpdate.PhysicsUpdate(deltaTime);
+
         for (int iterationIndex = 0; iterationIndex < IterationPerStep; iterationIndex++)
         {
             // Can Parallel
@@ -40,64 +49,118 @@ public class PhysicsEngine2D : UniverseObject, IPhysicsEngine2D
             {
                 ICollider2D? colliderX = colliderCollector.Behaviours[x];
                 if (!colliderX.IsActive)
-                    return;
+                    continue;
 
                 for (int y = x + 1; y < colliderCollector.Behaviours.Count; y++)
                 {
                     ICollider2D? colliderY = colliderCollector.Behaviours[y];
 
                     if (!colliderY.IsActive)
-                        return;
-
-                    if (colliderX.RigidBody2D == colliderY.RigidBody2D)
                         continue;
 
-                    bool bothCollidersAreTriggers = colliderX.IsTrigger && colliderX.IsTrigger == colliderY.IsTrigger;
+                    ResolveColliders(colliderX, colliderY);
-                    if (bothCollidersAreTriggers)
-                        continue;
-
-                    bool bothCollidersAreStatic = (colliderX.RigidBody2D?.IsStatic ?? true) && (colliderY.RigidBody2D?.IsStatic ?? true);
-                    if (bothCollidersAreStatic)
-                        continue;
-
-                    if (collisionDetector.TryDetect(colliderX, colliderY, out CollisionDetectionInformation information))
-                    {
-                        if (colliderX.IsTrigger)
-                        {
-                            colliderX.Trigger(colliderY);
-                            continue;
-                        }
-                        else if (colliderY.IsTrigger)
-                        {
-                            colliderY.Trigger(colliderX);
-                            continue;
-                        }
-
-                        if (information.Detector == colliderX)
-                        {
-                            colliderX.Detect(information);
-                            colliderY.Detect(information.Reverse());
-                        }
-                        else
-                        {
-                            colliderX.Detect(information.Reverse());
-                            colliderY.Detect(information);
-                        }
-
-                        collisionResolver?.Resolve(information);
-                    }
                 }
             }
 
             OnPhysicsIteration?.InvokeSafe(this, intervalDeltaTime);
         }
 
-        foreach (IPhysicsUpdate physicsUpdate in physicsUpdateCollector)
+        foreach (IPostPhysicsUpdate physicsPostUpdate in physicsPostUpdateCollector)
-            physicsUpdate.PhysicsUpdate(deltaTime);
+            physicsPostUpdate.PostPhysicsUpdate(deltaTime);
 
         OnPhysicsStep?.InvokeSafe(this, deltaTime);
     }
 
+    public void StepIndividual(IRigidBody2D rigidBody, float deltaTime)
+    {
+        float intervalDeltaTime = deltaTime / IterationPerStep;
+
+        System.Collections.Generic.List<ICollider2D> childColliders = [];
+        System.Collections.Generic.List<IPrePhysicsUpdate> physicsPreUpdates = [];
+        System.Collections.Generic.List<IPhysicsUpdate> physicsUpdates = [];
+        System.Collections.Generic.List<IPostPhysicsUpdate> physicsPostUpdates = [];
+
+        rigidBody.BehaviourController.GetBehavioursInChildren(childColliders);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsPreUpdates);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsUpdates);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsPostUpdates);
+
+        foreach (IPrePhysicsUpdate physicsPreUpdate in physicsPreUpdates)
+            physicsPreUpdate.PrePhysicsUpdate(deltaTime);
+
+        foreach (IPhysicsUpdate physicsUpdate in physicsUpdates)
+            physicsUpdate.PhysicsUpdate(deltaTime);
+
+        for (int iterationIndex = 0; iterationIndex < IterationPerStep; iterationIndex++)
+        {
+            StepRigidBody(rigidBody, intervalDeltaTime);
+
+            foreach (ICollider2D collider in childColliders)
+                collider.Recalculate();
+
+            for (int x = 0; x < childColliders.Count; x++)
+            {
+                ICollider2D? colliderX = childColliders[x];
+                if (!colliderX.IsActive)
+                    continue;
+
+                for (int y = 0; y < colliderCollector.Behaviours.Count; y++)
+                {
+                    ICollider2D? colliderY = colliderCollector.Behaviours[y];
+
+                    if (!colliderY.IsActive)
+                        continue;
+
+                    ResolveColliders(colliderX, colliderY);
+                }
+            }
+        }
+
+        foreach (IPostPhysicsUpdate physicsPostUpdate in physicsPostUpdates)
+            physicsPostUpdate.PostPhysicsUpdate(deltaTime);
+    }
+
+    private void ResolveColliders(ICollider2D colliderX, ICollider2D colliderY)
+    {
+        if (colliderX.RigidBody2D == colliderY.RigidBody2D)
+            return;
+
+        bool bothCollidersAreTriggers = colliderX.IsTrigger && colliderX.IsTrigger == colliderY.IsTrigger;
+        if (bothCollidersAreTriggers)
+            return;
+
+        bool bothCollidersAreStatic = (colliderX.RigidBody2D?.IsStatic ?? true) && (colliderY.RigidBody2D?.IsStatic ?? true);
+        if (bothCollidersAreStatic)
+            return;
+
+        if (!collisionDetector.TryDetect(colliderX, colliderY, out CollisionDetectionInformation information))
+            return;
+
+        if (colliderX.IsTrigger)
+        {
+            colliderX.Trigger(colliderY);
+            return;
+        }
+        else if (colliderY.IsTrigger)
+        {
+            colliderY.Trigger(colliderX);
+            return;
+        }
+
+        if (information.Detector == colliderX)
+        {
+            colliderX.Detect(information);
+            colliderY.Detect(information.Reverse());
+        }
+        else
+        {
+            colliderX.Detect(information.Reverse());
+            colliderY.Detect(information);
+        }
+
+        collisionResolver?.Resolve(information);
+    }
+
     private static void StepRigidBody(IRigidBody2D rigidBody, float intervalDeltaTime)
     {
         if (rigidBody.IsStatic || !rigidBody.IsActive)
@@ -109,7 +172,9 @@ public class PhysicsEngine2D : UniverseObject, IPhysicsEngine2D
 
     protected override void OnEnteringUniverse(IUniverse universe)
     {
+        physicsPreUpdateCollector.Assign(universe);
         physicsUpdateCollector.Assign(universe);
+        physicsPostUpdateCollector.Assign(universe);
         colliderCollector.Assign(universe);
         rigidBodyCollector.Assign(universe);
 
@@ -118,7 +183,9 @@ public class PhysicsEngine2D : UniverseObject, IPhysicsEngine2D
 
     protected override void OnExitingUniverse(IUniverse universe)
     {
+        physicsPreUpdateCollector.Unassign();
         physicsUpdateCollector.Unassign();
+        physicsPostUpdateCollector.Unassign();
         colliderCollector.Unassign();
         rigidBodyCollector.Unassign();
 

Engine.Physics2D/PhysicsEngine2DStandalone.cs

@@ -57,52 +57,15 @@ public class PhysicsEngine2DStandalone : IPhysicsEngine2D
             {
                 ICollider2D? colliderX = colliders[x];
                 if (!colliderX.IsActive)
-                    return;
+                    continue;
 
                 for (int y = x + 1; y < colliders.Count; y++)
                 {
                     ICollider2D? colliderY = colliders[y];
-
                     if (!colliderY.IsActive)
                         return;
 
-                    if (colliderX.RigidBody2D == colliderY.RigidBody2D)
+                    ResolveColliders(colliderX, colliderY);
-                        continue;
-
-                    bool bothCollidersAreTriggers = colliderX.IsTrigger && colliderX.IsTrigger == colliderY.IsTrigger;
-                    if (bothCollidersAreTriggers)
-                        continue;
-
-                    bool bothCollidersAreStatic = (colliderX.RigidBody2D?.IsStatic ?? true) && (colliderY.RigidBody2D?.IsStatic ?? true);
-                    if (bothCollidersAreStatic)
-                        continue;
-
-                    if (collisionDetector.TryDetect(colliderX, colliderY, out CollisionDetectionInformation information))
-                    {
-                        if (colliderX.IsTrigger)
-                        {
-                            colliderX.Trigger(colliderY);
-                            continue;
-                        }
-                        else if (colliderY.IsTrigger)
-                        {
-                            colliderY.Trigger(colliderX);
-                            continue;
-                        }
-
-                        if (information.Detector == colliderX)
-                        {
-                            colliderX.Detect(information);
-                            colliderY.Detect(information.Reverse());
-                        }
-                        else
-                        {
-                            colliderX.Detect(information.Reverse());
-                            colliderY.Detect(information);
-                        }
-
-                        collisionResolver?.Resolve(information);
-                    }
                 }
             }
             OnPhysicsIteration?.InvokeSafe(this, intervalDeltaTime);
@@ -110,6 +73,96 @@ public class PhysicsEngine2DStandalone : IPhysicsEngine2D
         OnPhysicsStep?.InvokeSafe(this, deltaTime);
     }
 
+    public void StepIndividual(IRigidBody2D rigidBody, float deltaTime)
+    {
+        float intervalDeltaTime = deltaTime / IterationPerStep;
+
+        List<ICollider2D> childColliders = [];
+        List<IPrePhysicsUpdate> physicsPreUpdates = [];
+        List<IPhysicsUpdate> physicsUpdates = [];
+        List<IPostPhysicsUpdate> physicsPostUpdates = [];
+
+        rigidBody.BehaviourController.GetBehavioursInChildren(childColliders);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsPreUpdates);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsUpdates);
+        rigidBody.BehaviourController.GetBehavioursInChildren(physicsPostUpdates);
+
+        foreach (IPrePhysicsUpdate physicsPreUpdate in physicsPreUpdates)
+            physicsPreUpdate.PrePhysicsUpdate(deltaTime);
+
+        foreach (IPhysicsUpdate physicsUpdate in physicsUpdates)
+            physicsUpdate.PhysicsUpdate(deltaTime);
+
+        for (int iterationIndex = 0; iterationIndex < IterationPerStep; iterationIndex++)
+        {
+            StepRigidBody(rigidBody, intervalDeltaTime);
+
+            foreach (ICollider2D collider in childColliders)
+                collider.Recalculate();
+
+            for (int x = 0; x < childColliders.Count; x++)
+            {
+                ICollider2D? colliderX = childColliders[x];
+                if (!colliderX.IsActive)
+                    continue;
+
+                for (int y = 0; y < colliders.Count; y++)
+                {
+                    ICollider2D? colliderY = colliders[y];
+
+                    if (!colliderY.IsActive)
+                        continue;
+
+                    ResolveColliders(colliderX, colliderY);
+                }
+            }
+        }
+
+        foreach (IPostPhysicsUpdate physicsPostUpdate in physicsPostUpdates)
+            physicsPostUpdate.PostPhysicsUpdate(deltaTime);
+    }
+
+    private void ResolveColliders(ICollider2D colliderX, ICollider2D colliderY)
+    {
+        if (colliderX.RigidBody2D == colliderY.RigidBody2D)
+            return;
+
+        bool bothCollidersAreTriggers = colliderX.IsTrigger && colliderX.IsTrigger == colliderY.IsTrigger;
+        if (bothCollidersAreTriggers)
+            return;
+
+        bool bothCollidersAreStatic = (colliderX.RigidBody2D?.IsStatic ?? true) && (colliderY.RigidBody2D?.IsStatic ?? true);
+        if (bothCollidersAreStatic)
+            return;
+
+        if (!collisionDetector.TryDetect(colliderX, colliderY, out CollisionDetectionInformation information))
+            return;
+
+        if (colliderX.IsTrigger)
+        {
+            colliderX.Trigger(colliderY);
+            return;
+        }
+        else if (colliderY.IsTrigger)
+        {
+            colliderY.Trigger(colliderX);
+            return;
+        }
+
+        if (information.Detector == colliderX)
+        {
+            colliderX.Detect(information);
+            colliderY.Detect(information.Reverse());
+        }
+        else
+        {
+            colliderX.Detect(information.Reverse());
+            colliderY.Detect(information);
+        }
+
+        collisionResolver?.Resolve(information);
+    }
+
     private static void StepRigidBody(IRigidBody2D rigidBody, float intervalDeltaTime)
     {
         if (rigidBody.IsStatic || !rigidBody.IsActive)

Engine.Serializers/Engine.Serializers.Yaml/Engine.Serializers.Yaml.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>Syntriax.Engine.Serializers.Yaml</RootNamespace>

Engine.Serializers/Engine.Serializers.Yaml/YamlSerializer.cs

@@ -20,7 +20,7 @@ public class YamlSerializer : Core.Serialization.ISerializer
     private readonly EntityRegistry entityRegistry = null!;
     private readonly IProgressionTracker progressionTracker = null!;
 
-    private readonly object Lock = new();
+    private readonly System.Threading.Lock Lock = new();
 
     public YamlSerializer()
     {

Engine.Systems/Engine.Systems.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>Syntriax.Engine.Systems</RootNamespace>

Engine.Systems/Tween/EngineExtensions/TweenTransform2DExtensions.cs

@@ -39,4 +39,69 @@ public static class TweenTransform2DExtensions
         float initialLocalRotation = transform2D.LocalRotation;
         return tweenManager.StartTween(duration, t => transform2D.LocalRotation = initialLocalRotation.Lerp(targetLocalRotation, t));
     }
+    public static ITween TweenPositionAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, Vector2D additivePosition)
+    {
+        Vector2D progressedPosition = Vector2D.Zero;
+        return tweenManager.StartTween(duration, t =>
+        {
+            Vector2D displacement = Vector2D.Zero.Lerp(additivePosition, t) - progressedPosition;
+            transform2D.Position += displacement;
+            progressedPosition += displacement;
+        });
+    }
+
+    public static ITween TweenScaleAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, Vector2D additiveScale)
+    {
+        Vector2D progressedScale = Vector2D.Zero;
+        return tweenManager.StartTween(duration, t =>
+        {
+            Vector2D displacement = Vector2D.Zero.Lerp(additiveScale, t) - progressedScale;
+            transform2D.Scale += displacement;
+            progressedScale += displacement;
+        });
+    }
+
+    public static ITween TweenRotationAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, float additiveRotation)
+    {
+        float progressedRotation = 0f;
+        return tweenManager.StartTween(duration, t =>
+        {
+            float displacement = 0f.Lerp(additiveRotation, t) - progressedRotation;
+            transform2D.Rotation += displacement;
+            progressedRotation += displacement;
+        });
+    }
+
+    public static ITween TweenLocalPositionAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, Vector2D additiveLocalPosition)
+    {
+        Vector2D progressedLocalPosition = Vector2D.Zero;
+        return tweenManager.StartTween(duration, t =>
+        {
+            Vector2D displacement = Vector2D.Zero.Lerp(additiveLocalPosition, t) - progressedLocalPosition;
+            transform2D.LocalPosition += displacement;
+            progressedLocalPosition += displacement;
+        });
+    }
+
+    public static ITween TweenLocalScaleAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, Vector2D additiveLocalScale)
+    {
+        Vector2D progressedLocalScale = Vector2D.Zero;
+        return tweenManager.StartTween(duration, t =>
+        {
+            Vector2D displacement = Vector2D.Zero.Lerp(additiveLocalScale, t) - progressedLocalScale;
+            transform2D.LocalScale += displacement;
+            progressedLocalScale += displacement;
+        });
+    }
+
+    public static ITween TweenLocalRotationAdditive(this ITransform2D transform2D, ITweenManager tweenManager, float duration, float additiveLocalRotation)
+    {
+        float progressedLocalRotation = 0f;
+        return tweenManager.StartTween(duration, t =>
+        {
+            float displacement = 0f.Lerp(additiveLocalRotation, t) - progressedLocalRotation;
+            transform2D.LocalRotation += displacement;
+            progressedLocalRotation += displacement;
+        });
+    }
 }

Engine/Engine.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>disable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>Syntriax.Engine</RootNamespace>