ECS - optimize Entity.AddComponent<>() / RemoveComponent<>()

src/ECS/Archetype/EntityStore.Archetype.cs

@@ -74,7 +74,7 @@ internal bool TryGetValue(ArchetypeKey searchKey, out ArchetypeKey archetypeKey)
         return archSet.TryGetValue(searchKey, out archetypeKey);
     }
 
-    private static Archetype GetArchetypeWith(EntityStoreBase store, Archetype current, int structIndex)
+    internal static Archetype GetArchetypeWith(EntityStoreBase store, Archetype current, int structIndex)
     {
         var key = store.searchKey;
         key.SetWith(current, structIndex);
@@ -89,7 +89,7 @@ private static Archetype GetArchetypeWith(EntityStoreBase store, Archetype curre
         return archetype;
     }
 
-    private static Archetype GetArchetypeWithout(EntityStoreBase store, Archetype archetype, int structIndex)
+    internal static Archetype GetArchetypeWithout(EntityStoreBase store, Archetype archetype, int structIndex)
     {
         var key = store.searchKey;
         key.SetWithout(archetype, structIndex);

src/ECS/Archetype/EntityStore.Mutation.cs

@@ -15,6 +15,7 @@ namespace Friflo.Engine.ECS;
 
 public partial class EntityStoreBase
 {
+/*
     // ------------------------------------ add / remove component ------------------------------------
 #region add / remove component
     internal static bool AddComponent<T>(
@@ -99,7 +100,8 @@ internal static bool RemoveComponent<T>(
         return true;
     }
     #endregion
-
+*/
+
     // ------------------------------------ add / remove entity Tag ------------------------------------
 #region add / remove tags
 

src/ECS/Archetype/EntityStore.cs

@@ -91,11 +91,10 @@ public abstract partial class EntityStoreBase
     [Browse(Never)] internal            int                     singleIndex;        //  4
     [Browse(Never)] internal            bool                    shrinkArchetypes;   //  1
 
-                    private             InternBase              internBase;         // 88
+                    internal            InternBase              internBase;         // 88
     /// <summary>Contains state of <see cref="EntityStoreBase"/> not relevant for application development.</summary>
     /// <remarks>Declaring internal state fields in this struct remove noise in debugger.</remarks>
-    // MUST be private by all means 
-    private struct InternBase {
+    internal struct InternBase {
         internal        long                                        archetypesCapacity;     // 16   - sum of all Archetype capacities
         internal        double                                      shrinkRatio;            //  8
         // --- delegates
@@ -191,13 +190,13 @@ internal static ArgumentException IdOutOfRangeException(EntityStore store, int i
         return new ArgumentException($"id: {id}. expect in [0, current max id: {store.nodes.Length - 1}]");
     }
 
-    private static ArgumentException AddRelationException(int id, int structIndex) {
+    internal static ArgumentException AddRelationException(int id, int structIndex) {
         var componentType   = Static.EntitySchema.components[structIndex];
         var type            = componentType.Name;
         return new ArgumentException($"relation component must be added with:  entity.{nameof(RelationExtensions.AddRelation)}(new {type}());  id: {id}");
     }
 
-    private static ArgumentException RemoveRelationException(int id, int structIndex) {
+    internal static ArgumentException RemoveRelationException(int id, int structIndex) {
         var componentType   = Static.EntitySchema.components[structIndex];
         var type            = componentType.Name;
         var keyType         = componentType.RelationKeyType.Name;

src/ECS/Base/Types/ComponentType.cs

@@ -94,31 +94,16 @@ internal ComponentType(string componentKey, int structIndex, Type indexType, Typ
     }
 
     internal override bool RemoveEntityComponent(Entity entity) {
-        int archIndex = 0;
-        ref var node    = ref entity.store.nodes[entity.Id];
-        if (node.IsAlive(entity.Revision)) {
-            return EntityStoreBase.RemoveComponent<T>(entity.Id, ref node.archetype, ref node.compIndex, ref archIndex, StructIndex);
-        }
-        throw EntityStoreBase.EntityArgumentNullException(entity, nameof(entity));
+        return entity.RemoveComponent<T>();
     }
 
     internal override bool AddEntityComponent(Entity entity) {
-        int archIndex = 0;
-        ref var node    = ref entity.store.nodes[entity.Id];
-        if (node.IsAlive(entity.Revision)) {
-            return EntityStoreBase.AddComponent<T>(entity.Id, StructIndex, ref node.archetype, ref node.compIndex, ref archIndex, default);
-        }
-        throw EntityStoreBase.EntityArgumentNullException(entity, nameof(entity));
+        return entity.AddComponent<T>(default);
     }
 
     internal override bool AddEntityComponentValue(Entity entity, object value) {
-        int archIndex = 0;
         var componentValue = (T)value;
-        ref var node    = ref entity.store.nodes[entity.Id];
-        if (node.IsAlive(entity.Revision)) {
-            return EntityStoreBase.AddComponent(entity.Id, StructIndex, ref node.archetype, ref node.compIndex, ref archIndex, componentValue);
-        }
-        throw EntityStoreBase.EntityArgumentNullException(entity, nameof(entity));
+        return entity.AddComponent(componentValue);
     }
 
     internal override StructHeap CreateHeap() {

src/ECS/Entity.cs

@@ -176,7 +176,7 @@ namespace Friflo.Engine.ECS;
 /// </remarks>
 [CLSCompliant(true)]
 [StructLayout(LayoutKind.Explicit)]
-public readonly struct Entity : IEquatable<Entity>
+public readonly partial struct Entity : IEquatable<Entity>
 {
     // ------------------------------------ general properties ------------------------------------
 #region general properties
@@ -424,13 +424,10 @@ public bool     TryGetComponent<T>(out T result) where T : struct, IComponent
     /// <returns>true - component is newly added to the entity.<br/> false - component is updated.</returns>
     /// <remarks>Note: Use <see cref="EntityUtils.AddEntityComponent"/> as non generic alternative</remarks>
     public bool AddComponent<T>()               where T : struct, IComponent {
-        int archIndex   = 0;
-        ref var node    = ref store.nodes[Id];
-        if (node.IsAlive(Revision)) {
-            return EntityStoreBase.AddComponent<T>(Id, StructInfo<T>.Index, ref node.archetype, ref node.compIndex, ref archIndex, default);
-        }
-        throw EntityNullException();
+        return AddComponent<T>(default);
     }
+
+    /*
     /// <summary>
     /// Add the given <paramref name="component"/> to the entity.<br/>
     /// If the entity contains a component of the same type it is updated.<br/>
@@ -458,7 +455,7 @@ public bool RemoveComponent<T>()            where T : struct, IComponent {
             return EntityStoreBase.RemoveComponent<T>(Id, ref node.archetype, ref node.compIndex, ref archIndex, StructInfo<T>.Index);
         }
         throw EntityNullException();
-    }
+    }*/
     #endregion
 
 

src/ECS/Entity/Mutation.cs

@@ -0,0 +1,104 @@
+// Copyright (c) Ullrich Praetz - https://github.com/friflo. All rights reserved.
+// See LICENSE file in the project root for full license information.
+
+using Friflo.Engine.ECS.Index;
+
+// ReSharper disable once CheckNamespace
+namespace Friflo.Engine.ECS;
+
+public readonly partial struct  Entity
+{ 
+    /// <summary>
+    /// Add the given <paramref name="component"/> to the entity.<br/>
+    /// If the entity contains a component of the same type it is updated.<br/>
+    /// See <a href="https://friflo.gitbook.io/friflo.engine.ecs/examples/general#component">Example.</a>
+    /// </summary>
+    /// <returns>true - component is newly added to the entity.<br/> false - component is updated.</returns>
+    public bool AddComponent<T>(in T component)      where T : struct, IComponent
+    {
+        int id          = Id;
+        var localStore  = store;
+        ref var node    = ref localStore.nodes[id];
+        var arch        = node.archetype;
+        if (arch == null || Revision != node.revision) {
+            throw EntityNullException();  
+        }
+        int structIndex = StructInfo<T>.Index;
+        ComponentChangedAction  action;
+        bool                    added;
+        if (StructInfo<T>.IsRelation) {
+            throw EntityStoreBase.AddRelationException(id, structIndex);
+        }
+        int localCompIndex  = node.compIndex;
+        var oldHeap         = (StructHeap<T>)arch.heapMap[structIndex];
+        StructHeap<T> newHeap;
+        if (oldHeap != null) {
+            // --- case: archetype contains the component type  => archetype remains unchanged
+            oldHeap.componentStash = oldHeap.components[localCompIndex];
+            added   = false;
+            action  = ComponentChangedAction.Update;
+            if (StructInfo<T>.HasIndex) StoreIndex.UpdateIndex(localStore, id, component, oldHeap);
+            newHeap = oldHeap;
+            goto AssignComponent;
+        }
+        // --- case: archetype doesn't contain component type   => change entity archetype
+        var newArchetype    = EntityStoreBase.GetArchetypeWith(localStore, arch, structIndex);
+        localCompIndex      = Archetype.MoveEntityTo(arch, id, localCompIndex, newArchetype);
+        node.compIndex      = localCompIndex;
+        node.archetype      = arch = newArchetype;
+        added               = true;
+        action              = ComponentChangedAction.Add;
+        if (StructInfo<T>.HasIndex) StoreIndex.AddIndex(localStore, id, component);
+        newHeap             = (StructHeap<T>)arch.heapMap[structIndex];
+
+    AssignComponent:  // --- assign passed component value
+        newHeap.components[localCompIndex]  = component;
+        // Send event. See: SEND_EVENT notes
+        var componentAdded = localStore.internBase.componentAdded;
+        if (componentAdded == null) {
+            return added;
+        }
+        componentAdded.Invoke(new ComponentChanged (localStore, id, action, structIndex, oldHeap));
+        return added;
+    }
+
+    /// <summary>Remove the component of the given type from the entity.</summary>
+    /// <returns>true if entity contained a component of the given type before</returns>
+    /// <remarks>
+    /// Executes in O(1)<br/>
+    /// <remarks>Note: Use <see cref="EntityUtils.RemoveEntityComponent"/> as non generic alternative</remarks>
+    /// </remarks>
+    public bool RemoveComponent<T>()            where T : struct, IComponent
+    {
+        var id              = Id;
+        int structIndex     = StructInfo<T>.Index;
+        var localStore      = store;
+        ref var node        = ref localStore.nodes[id];
+        var arch            = node.archetype;
+        if (arch == null || Revision != node.revision) {
+            throw EntityNullException();
+        }
+        if (StructInfo<T>.IsRelation) {
+            throw EntityStoreBase.RemoveRelationException(id, structIndex);
+        }
+        int localCompIndex  = node.compIndex;
+        var heap            = (StructHeap<T>)arch.heapMap[structIndex];
+        if (heap == null) {
+            return false;
+        }
+        heap.componentStash = heap.components[localCompIndex];
+        if (StructInfo<T>.HasIndex) StoreIndex.RemoveIndex(localStore, id, heap);
+        var newArchetype = EntityStoreBase.GetArchetypeWithout(localStore, arch, structIndex);
+
+        // --- change entity archetype
+        node.archetype   = newArchetype;
+        node.compIndex   = Archetype.MoveEntityTo(arch, id, localCompIndex, newArchetype);
+        // Send event. See: SEND_EVENT notes
+        var componentRemoved = localStore.internBase.componentRemoved;
+        if (componentRemoved == null) {
+            return true;
+        }
+        componentRemoved.Invoke(new ComponentChanged (localStore, id, ComponentChangedAction.Remove, structIndex, heap));
+        return true;
+    }
+}

src/ECS/RawEntity/RawEntityStore.cs

@@ -2,6 +2,7 @@
 // See LICENSE file in the project root for full license information.
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 
 // Hard rule: this file MUST NOT use type: Entity
 
@@ -135,21 +136,18 @@ public ref T GetEntityComponent<T>(int id)
         return ref heap.components[entity.compIndex];
     }
 
+    [ExcludeFromCodeCoverage]
     public bool AddEntityComponent<T>(int id, in T component)
         where T : struct, IComponent
     {
-        ref var entity      = ref entities[id];
-        var archetype       = archs[entity.archIndex];
-        var structIndex     = StructInfo<T>.Index;
-        return AddComponent(id, structIndex, ref archetype, ref entity.compIndex, ref entity.archIndex, component);
+        throw new NotImplementedException($"{nameof(RawEntityStore)} will be removed");
     }
 
+    [ExcludeFromCodeCoverage]
     public bool RemoveEntityComponent<T>(int id)
         where T : struct, IComponent
     {
-        ref var entity      = ref entities[id];
-        var archetype       = archs[entity.archIndex];
-        return RemoveComponent<T>(id, ref archetype, ref entity.compIndex, ref entity.archIndex, StructInfo<T>.Index);
+        throw new NotImplementedException($"{nameof(RawEntityStore)} will be removed");
     }
     #endregion
 

src/Tests/ECS/Entity/Test_Entity_NRE.cs

@@ -70,20 +70,20 @@ public static void Test_Entity_NRE_Component()
         var schema = EntityStore.GetEntitySchema();
         var componentType = schema.ComponentTypeByType[typeof(Position)];
 
-        var ane = Throws<ArgumentException>(() => {
+        nre = Throws<NullReferenceException>(() => {
             EntityUtils.RemoveEntityComponent(entity, componentType);
         });
-        AreEqual(expectArg, ane!.Message);
+        AreEqual(expect, nre!.Message);
 
-        ane = Throws<ArgumentException>(() => {
+        nre = Throws<NullReferenceException>(() => {
             EntityUtils.AddEntityComponent(entity, componentType);
         });
-        AreEqual(expectArg, ane!.Message);
+        AreEqual(expect, nre!.Message);
 
-        ane = Throws<ArgumentException>(() => {
+        nre = Throws<NullReferenceException>(() => {
             EntityUtils.AddEntityComponentValue(entity, componentType, new Position());
         });
-        AreEqual(expectArg, ane!.Message);
+        AreEqual(expect, nre!.Message);
 
         // --- tags
         nre = Throws<NullReferenceException>(() => {
@@ -106,7 +106,7 @@ public static void Test_Entity_NRE_Component()
         });
         AreEqual(expect, nre!.Message);
 
-        ane = Throws<ArgumentException>(() => {
+        var ane = Throws<ArgumentException>(() => {
             store.CloneEntity(entity);
         });
         AreEqual(expectArg, ane!.Message);

src/Tests/ECS/Raw/Test_RawEntities.cs

@@ -12,7 +12,7 @@ namespace Tests.ECS.Raw {
 public static class Test_RawEntities
 {
     /// <summary>Similar to <see cref="Test_StructComponent.Test_9_RemoveComponent"/></summary>
-    [Test]
+    // [Test]
     public static void Test_RawEntities_Components()
     {
         var store   = new RawEntityStore();