Unstable v0.1300.0.0 (February 19th 2021)

Barotrauma/BarotraumaShared/SharedSource/Prefabs/IPrefab.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Security.Cryptography;
 using System.Text;
 
 namespace Barotrauma
@@ -11,4 +12,28 @@ namespace Barotrauma
         string FilePath { get; }
         ContentPackage ContentPackage { get; }
     }
+
+    public interface IHasUintIdentifier
+    {
+        uint UIntIdentifier { get; set; }
+    }
+
+    public static class PrefabExtensions
+    {
+        public static void CalculatePrefabUIntIdentifier<T>(this T prefab, PrefabCollection<T> prefabs) where T : class, IPrefab, IHasUintIdentifier, IDisposable
+        {
+            using (MD5 md5 = MD5.Create())
+            {
+                prefab.UIntIdentifier = ToolBox.StringToUInt32Hash(prefab.Identifier, md5);
+
+                //it's theoretically possible for two different values to generate the same hash, but the probability is astronomically small
+                var collision = prefabs.Find(p => p != prefab && p.UIntIdentifier == prefab.UIntIdentifier);
+                if (collision != null)
+                {
+                    DebugConsole.ThrowError($"Hashing collision when generating uint identifiers for {nameof(T)}: {prefab.Identifier} has the same identifier as {collision.Identifier} ({prefab.UIntIdentifier})");
+                    collision.UIntIdentifier++;
+                }
+            }
+        }
+    }
 }