Load additive

closes #9

Editor/ScenePartitionSO.cs

@@ -235,6 +235,35 @@ public void LoadPartitions(ulong[] ids)
             }
         }
 
+        public void LoadPartitionsAdditive(ulong[] ids)
+        {
+            using (new ProfilerUtility.ProfilerScope($"{nameof(LoadPartitions)}"))
+            {
+                SortedSet<ulong> partitionIds = new SortedSet<ulong>();
+
+                // Additive partitions to load.
+                for (int i = 0; i < ids.Length; i++)
+                {
+                    SortedSet<ulong> connections = ScenePartitionUtils.FindDeeplyLinkedObjects(Data.ScenePartitions, ids[i]);
+                    foreach (ulong c in connections)
+                    {
+                        partitionIds.Add(c);
+                    }
+                }
+
+                // Partitions already loaded.
+                if (Data.HasLoadedPartitions)
+                {
+                    foreach (KeyValuePair<ulong, ScenePartition> item in Data.LoadedScenePartitions)
+                    {
+                        partitionIds.Add(item.Key);
+                    }
+                }
+
+                LoadScenePartitions(partitionIds);
+            }
+        }
+
         private SortedSet<ulong> GetAlwaysLoadIds()
         {
             SortedSet<ulong> partitionIds = new SortedSet<ulong>();
@@ -336,6 +365,14 @@ public void LoadCell(int gridId)
             }
         }
 
+        public void LoadCellAdditive(int gridId)
+        {
+            if (Data.SceneGrid.Grid.TryGetValue(gridId, out GridList ids))
+            {
+                LoadPartitionsAdditive(ids.list.ToArray());
+            }
+        }
+
         public void ClearCache()
         {
             data = null;

Editor/ScenePartitionSceneViewEditor.cs

@@ -66,6 +66,7 @@ private static void HandleDuringSceneGui(SceneView sceneView)
                 GenericMenu menu = new GenericMenu();
 
                 menu.AddItem(new GUIContent($"Load {gridId}"), false, Load, gridId);
+                menu.AddItem(new GUIContent($"LoadAdditive {gridId}"), false, LoadAdditive, gridId);
                 menu.ShowAsContext();
 
                 Event.current.Use();
@@ -95,5 +96,14 @@ private static void Load(object gridId)
 
             scenePartitionSO.LoadCell(cellId);
         }
+
+        private static void LoadAdditive(object gridId)
+        {
+            if (scenePartitionSO == null) return;
+            if (gridId == null) return;
+            if (gridId is not int cellId) return;
+
+            scenePartitionSO.LoadCellAdditive(cellId);
+        }
     }
 }