Combined transform systems

Profiler window calls count
Parallel transform system is now in the normal transform system
Removed unused parent system

Nerfed.Runtime/Systems/LocalToWorldSystem.cs

@@ -15,19 +15,62 @@ namespace Nerfed.Runtime.Systems
 {
     public class LocalToWorldSystem : MoonTools.ECS.System
     {
+        private readonly bool useParallelFor = false; // When having a low amount of transforms or when in debug mode this might be slower.
         private readonly Filter rootEntitiesFilter;
+        private readonly Filter transformEntitiesFilter;
+        private readonly Action<int> updateWorldTransform;
 
         public LocalToWorldSystem(World world) : base(world)
         {
             rootEntitiesFilter = FilterBuilder.Include<LocalTransform>().Exclude<Child>().Build();
+            if (useParallelFor)
+            {
+                transformEntitiesFilter = FilterBuilder.Include<LocalTransform>().Build();
+                updateWorldTransform = UpdateWorldTransformByIndex;
+            }
         }
 
         public override void Update(TimeSpan delta)
         {
-            foreach (Entity entity in rootEntitiesFilter.Entities)
+            if (rootEntitiesFilter.Empty)
             {
-                UpdateWorldTransform(entity, Matrix4x4.Identity);
+                return;
             }
+
+            if (useParallelFor)
+            {
+                Profiler.BeginSample("ParallelFor.LocalToWorldCheck");
+                // This check is needed because some entities might not have a LocalToWorld component yet.
+                // Adding this during the loop will break.
+                foreach (Entity entity in transformEntitiesFilter.Entities) {
+                    if (Has<LocalToWorld>(entity))
+                    {
+                        continue;
+                    }
+
+                    Set(entity, new LocalToWorld(Matrix4x4.Identity));
+                }
+                Profiler.EndSample();
+
+                Profiler.BeginSample("ParallelFor.LocalToWorldUpdate");
+                // This should only be used when the filter doesn't change by executing these functions!
+                // So no entity deletion or setting/removing of components used by the filters in this loop.
+                Parallel.For(0, rootEntitiesFilter.Count, updateWorldTransform);
+                Profiler.EndSample();
+            }
+            else
+            {
+                foreach (Entity entity in rootEntitiesFilter.Entities)
+                {
+                    UpdateWorldTransform(entity, Matrix4x4.Identity);
+                }
+            }
+        }
+
+        private void UpdateWorldTransformByIndex(int entityFilterIndex)
+        {
+            Entity entity = rootEntitiesFilter.NthEntity(entityFilterIndex);
+            UpdateWorldTransform(entity, Matrix4x4.Identity);
         }
 
         private void UpdateWorldTransform(in Entity entity, Matrix4x4 localToWorldMatrix)
@@ -41,8 +84,6 @@ namespace Nerfed.Runtime.Systems
                 localToWorldMatrix = Matrix4x4.Multiply(localToWorldMatrix, localTransform.TRS());
                 LocalToWorld localToWorld = new(localToWorldMatrix);
                 Set(entity, localToWorld);
-                //Task.Delay(10).Wait();
-                //Log.Info($"Entity {entity} | local position {localTransform.position} | world position {localToWorldMatrix.Translation}");
             }
 
             ReverseSpanEnumerator<Entity> childEntities = World.InRelations<ChildParentRelation>(entity);