replace SHA256 hash to FNV1a 64bit hash because it's crashes on Godot…

…/Net8 android
RevenantX · Feb 8, 2024 · 3d80a5a · 3d80a5a
1 parent 0cbe30a
commit 3d80a5a
Show file tree

Hide file tree

Showing 2 changed files with 15 additions and 19 deletions.
diff --git a/LiteEntitySystem/EntityTypesMap.cs b/LiteEntitySystem/EntityTypesMap.cs
@@ -2,8 +2,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
-using System.Security.Cryptography;
-using System.Text;
 using LiteEntitySystem.Internal;
 
 namespace LiteEntitySystem
@@ -24,7 +22,6 @@ public abstract class EntityTypesMap
     {
         internal ushort MaxId;
         internal readonly Dictionary<Type, RegisteredTypeInfo> RegisteredTypes = new();
-        private readonly SHA256 _sha256 = SHA256.Create();
         private bool _isFinished;
         private const BindingFlags FieldsFlags = BindingFlags.Instance |
                                                  BindingFlags.Public |
@@ -35,8 +32,11 @@ public abstract class EntityTypesMap
         /// Can be used to detect that server/client has difference
         /// </summary>
         /// <returns>hash</returns>
-        public byte[] EvaluateEntityClassDataHash()
+        public ulong EvaluateEntityClassDataHash()
         {
+            //FNV1a 64 bit hash
+            ulong hash = 14695981039346656037UL; //offset
+
             if (!_isFinished)
             {
                 foreach (var (entType, _) in RegisteredTypes.OrderBy(kv => kv.Value.ClassId))
@@ -57,20 +57,22 @@ public byte[] EvaluateEntityClassDataHash()
                         }
                     }
                 }
-                _sha256.TransformFinalBlock(new byte[]{ 255 }, 0, 1);
                 _isFinished = true;
             }
-
-            return _sha256.Hash;
+            return hash;
 
             void TryHashField(FieldInfo fi)
             {
                 var ft = fi.FieldType;
                 if ((fi.IsStatic && EntityClassData.IsRemoteCallType(ft)) || 
                     (ft.IsGenericType && !ft.IsArray && ft.GetGenericTypeDefinition() == typeof(SyncVar<>)))
                 {
-                    byte[] ftName = Encoding.ASCII.GetBytes(ft.Name + (ft.IsGenericType ? ft.GetGenericArguments()[0].Name : string.Empty));
-                    _sha256.TransformBlock(ftName, 0, ftName.Length, null, 0);
+                    string ftName = ft.Name + (ft.IsGenericType ? ft.GetGenericArguments()[0].Name : string.Empty);
+                    for (int i = 0; i < ftName.Length; i++)
+                    {
+                        hash ^= ftName[i];
+                        hash *= 1099511628211UL; //prime
+                    }
                 }
             }
         }

diff --git a/LiteEntitySystem/ServerEntityManager.cs b/LiteEntitySystem/ServerEntityManager.cs
@@ -196,15 +196,12 @@ public ControllerLogic GetPlayerController(NetPlayer player)
         /// <param name="initMethod">Method that will be called after entity construction</param>
         /// <typeparam name="T">Entity type</typeparam>
         /// <returns>Created entity or null in case of limit</returns>
-        public T AddController<T>(NetPlayer owner, Action<T> initMethod = null) where T : ControllerLogic
-        {
-            var result = Add<T>(ent =>
+        public T AddController<T>(NetPlayer owner, Action<T> initMethod = null) where T : ControllerLogic =>
+            Add<T>(ent =>
             {
                 ent.InternalOwnerId = owner.Id;
                 initMethod?.Invoke(ent);
             });
-            return result;
-        }
 
         /// <summary>
         /// Add new player controller entity and start controlling entityToControl
@@ -214,16 +211,13 @@ public T AddController<T>(NetPlayer owner, Action<T> initMethod = null) where T
         /// <param name="initMethod">Method that will be called after entity construction</param>
         /// <typeparam name="T">Entity type</typeparam>
         /// <returns>Created entity or null in case of limit</returns>
-        public T AddController<T>(NetPlayer owner, PawnLogic entityToControl, Action<T> initMethod = null) where T : ControllerLogic
-        {
-            var result = Add<T>(ent =>
+        public T AddController<T>(NetPlayer owner, PawnLogic entityToControl, Action<T> initMethod = null) where T : ControllerLogic =>
+            Add<T>(ent =>
             {
                 ent.InternalOwnerId = owner.Id;
                 ent.StartControl(entityToControl);
                 initMethod?.Invoke(ent);
             });
-            return result;
-        }
 
         /// <summary>
         /// Add new AI controller entity