ECS - Relations: fix #11

src/ECS/Archetype/Archetype.cs

@@ -277,11 +277,11 @@ internal static int MoveEntityTo(Archetype sourceArch, int id, int sourceIndex,
             // This is redundant for Entity.AddComponent() but other callers may not assign a component value.
             targetHeap.SetComponentDefault(targetIndex);
         }
-        MoveLastComponentsTo(sourceArch, sourceIndex);
+        MoveLastComponentsTo(sourceArch, sourceIndex, true);
         return targetIndex;
     }
 
-    internal static void MoveLastComponentsTo(Archetype arch, int newIndex)
+    internal static void MoveLastComponentsTo(Archetype arch, int newIndex, bool updateCompIndex)
     {
         var lastIndex   = arch.entityCount - 1;
         var store       = arch.store;
@@ -292,8 +292,9 @@ internal static void MoveLastComponentsTo(Archetype arch, int newIndex)
             }
             var entityIds       = arch.entityIds;
             var lastEntityId    = entityIds[lastIndex];
-            store.UpdateEntityCompIndex(lastEntityId, newIndex); // set entity component index for new archetype
-
+            if (updateCompIndex) {
+                store.UpdateEntityCompIndex(lastEntityId, newIndex); // set entity component index for new archetype
+            }
             entityIds[newIndex] = lastEntityId;
         }   // ReSharper disable once RedundantIfElseBlock
         else {

src/ECS/Entity.cs

@@ -622,8 +622,8 @@ public void DeleteEntity()
                 store.DeleteEntityEvent(this);
             }
             finally {
-                store.DeleteNode(this); 
-                Archetype.MoveLastComponentsTo(node.archetype, node.compIndex);
+                store.DeleteNode(this);
+                Archetype.MoveLastComponentsTo(node.archetype, node.compIndex, true);
             }
             return;
         }

src/ECS/RawEntity/RawEntityStore.cs

@@ -114,7 +114,7 @@ public bool DeleteEntity(int id)
             return false;
         }
         var archetype   = archs[archIndex];
-        Archetype.MoveLastComponentsTo(archetype, entity.compIndex);
+        Archetype.MoveLastComponentsTo(archetype, entity.compIndex, true);
         entity.archIndex = 0;
         entity.compIndex = 0;
         entityCount--;

src/ECS/Relations/Internal/EntityRelations.cs

@@ -211,7 +211,7 @@ protected IdArray RemoveEntityRelation(int id, int position, IdArray positions,
         }
 
         // --- move last relation to position of removed relation
-        Archetype.MoveLastComponentsTo(type, position);
+        Archetype.MoveLastComponentsTo(type, position, false);
         if (positions.count == 1) {
             map.Remove(id);
             store.nodes[id].isOwner &= ~relationBit;

src/Tests/ECS/Relations/Test_Relations_GitHub_11.cs

@@ -0,0 +1,33 @@
+using System;
+using Friflo.Engine.ECS;
+using NUnit.Framework;
+
+// ReSharper disable InconsistentNaming
+namespace Tests.ECS.Relations
+{
+    // Fix https://github.com/friflo/Friflo.Engine.ECS/issues/11
+    public static class Test_Relations_GitHub_11
+    {
+        [Test]
+        public static void Test_Rel_Test()
+        {
+            var store = new EntityStore();
+            var entity1 = store.CreateEntity();
+            entity1.Add(new MyComponent1 { a = 1 });
+
+            var entity2 = store.CreateEntity();
+            entity2.Add(new MyComponent1 { a = 2 });
+
+            var entity3 = store.CreateEntity();
+
+            entity1.AddRelation(new AttackRelation { target = entity3 });
+            entity2.AddRelation(new AttackRelation { target = entity3 });
+
+            entity1.RemoveRelation<AttackRelation>(entity3);
+
+            Assert.AreEqual(1, entity1.GetComponent<MyComponent1>().a);
+            Assert.AreEqual(2, entity2.GetComponent<MyComponent1>().a);
+            Console.WriteLine($"{entity1.GetComponent<MyComponent1>().a} {entity2.GetComponent<MyComponent1>().a}");
+        }
+    }
+}