Revert "OBT1.1.0 Merge branch 'dev_pte' into dev"

This reverts commit 177cf89756, reversing
changes made to 42ba733cd4.

Barotrauma/BarotraumaShared/SharedSource/Map/Entity.cs

@@ -1,6 +1,5 @@
 using Microsoft.Xna.Framework;
 using System;
-using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
 using Barotrauma.IO;
@@ -21,10 +20,10 @@ namespace Barotrauma
 
         public const ushort MaxEntityCount = ushort.MaxValue - 4; //ushort.MaxValue - 4 because the 4 values above are reserved values
 
-        private static readonly ConcurrentDictionary<ushort, Entity> dictionary = new ConcurrentDictionary<ushort, Entity>();
+        private static readonly Dictionary<ushort, Entity> dictionary = new Dictionary<ushort, Entity>();
         public static IReadOnlyCollection<Entity> GetEntities()
         {
-            return (IReadOnlyCollection<Entity>)dictionary.Values;
+            return dictionary.Values;
         }
 
         public static int EntityCount => dictionary.Count;
@@ -123,11 +122,13 @@ namespace Barotrauma
             //give a unique ID
             ID = DetermineID(id, submarine);
 
-            if (!dictionary.TryAdd(ID, this))
+            if (dictionary.ContainsKey(ID))
             {
                 throw new Exception($"ID {ID} is taken by {dictionary[ID]}");
             }
 
+            dictionary.Add(ID, this);
+
             CreationStackTrace = "";
 #if DEBUG
             var st = new StackTrace(skipFrames: 2, fNeedFileInfo: true);
@@ -146,6 +147,7 @@ namespace Barotrauma
                 CreationStackTrace += $"{fileName}@{fileLineNumber}; ";
             }
 #endif
+            #warning TODO: consider removing this mutex, entity creation probably shouldn't be multithreaded
             lock (creationCounterMutex)
             {
                 CreationIndex = creationCounter;
@@ -259,7 +261,7 @@ namespace Barotrauma
                         DebugConsole.ThrowError($"Error while removing item \"{item}\"", exception);
                     }
                 }
-                Item.ClearAllItemCollections();
+                Item.ItemList.Clear();
             }
             if (Character.CharacterList.Count > 0)
             {
@@ -323,7 +325,7 @@ namespace Barotrauma
             }
             else
             {
-                dictionary.TryRemove(ID, out _);
+                dictionary.Remove(ID);
             }
             IdFreed = true;
         }