From 4081693d3212952caffd06be409c7cef518ab883 Mon Sep 17 00:00:00 2001
From: Syntriax <syntriax@gmail.com>
Date: Fri, 11 Apr 2025 23:28:46 +0300
Subject: [PATCH] fix: removing an object from hierarchy setting all children's
 parents null

---
 Engine.Core/GameManager.cs     | 7 ++++++-
 Engine.Core/HierarchyObject.cs | 1 -
 Engine.Core/Transform2D.cs     | 2 --
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/Engine.Core/GameManager.cs b/Engine.Core/GameManager.cs
index 5aa3bd0..d86e993 100644
--- a/Engine.Core/GameManager.cs
+++ b/Engine.Core/GameManager.cs
@@ -68,6 +68,12 @@ public class GameManager : BaseEntity, IGameManager
     }
 
     public void Remove(IHierarchyObject hierarchyObject)
+    {
+        hierarchyObject.SetParent(null);
+        RemoveIncursive(hierarchyObject);
+    }
+
+    private void RemoveIncursive(IHierarchyObject hierarchyObject)
     {
         if (!_hierarchyObjects.Contains(hierarchyObject))
             throw new Exception($"{nameof(IHierarchyObject)} named {hierarchyObject.Name} is not registered to the {nameof(GameManager)}.");
@@ -79,7 +85,6 @@ public class GameManager : BaseEntity, IGameManager
             Remove(hierarchyObject.Children[i]);
 
         _hierarchyObjects.Remove(hierarchyObject);
-        hierarchyObject.SetParent(null);
 
         if (!hierarchyObject.ExitHierarchy())
             throw new Exception($"{hierarchyObject.Name} can't exit the hierarchy");
diff --git a/Engine.Core/HierarchyObject.cs b/Engine.Core/HierarchyObject.cs
index c9fb225..87316f8 100644
--- a/Engine.Core/HierarchyObject.cs
+++ b/Engine.Core/HierarchyObject.cs
@@ -64,7 +64,6 @@ public class HierarchyObject : BaseEntity, IHierarchyObject
 
         OnExitingHierarchy(gameManager);
         _gameManager = null!;
-        SetParent(null);
         OnExitedHierarchy?.Invoke(this, gameManager);
         return true;
     }
diff --git a/Engine.Core/Transform2D.cs b/Engine.Core/Transform2D.cs
index 176efd3..b2a1eb1 100644
--- a/Engine.Core/Transform2D.cs
+++ b/Engine.Core/Transform2D.cs
@@ -220,7 +220,6 @@ public class Transform2D : Behaviour, ITransform2D
         ITransform2D? previousParent = parentTransform;
         if (previousParent is not null)
         {
-            previousParent.BehaviourController.HierarchyObject.RemoveChild(HierarchyObject);
             previousParent.OnPositionChanged -= RecalculatePosition;
             previousParent.OnScaleChanged -= RecalculateScale;
             previousParent.OnRotationChanged -= RecalculateRotation;
@@ -232,7 +231,6 @@ public class Transform2D : Behaviour, ITransform2D
 
         if (parentTransform is not null)
         {
-            parentTransform.BehaviourController.HierarchyObject.AddChild(HierarchyObject);
             parentTransform.OnPositionChanged += RecalculatePosition;
             parentTransform.OnScaleChanged += RecalculateScale;
             parentTransform.OnRotationChanged += RecalculateRotation;