Merge pull request #95225 from Hilderin/fix-performance-reimport-file

Fix performance issue reimport file reload scene

editor/editor_node.cpp

@@ -3870,17 +3870,18 @@ void EditorNode::_set_current_scene_nocheck(int p_idx) {
 	changing_scene = true;
 	editor_data.save_edited_scene_state(editor_selection, &editor_history, _get_main_scene_state());
 
-	if (get_editor_data().get_edited_scene_root()) {
+	Node *old_scene = get_editor_data().get_edited_scene_root();
-		if (get_editor_data().get_edited_scene_root()->get_parent() == scene_root) {
-			scene_root->remove_child(get_editor_data().get_edited_scene_root());
-		}
-	}
 
 	editor_selection->clear();
 	editor_data.set_edited_scene(p_idx);
 
 	Node *new_scene = editor_data.get_edited_scene_root();
 
+	// Remove the scene only if it's a new scene, preventing performance issues when adding and removing scenes.
+	if (old_scene && new_scene != old_scene && old_scene->get_parent() == scene_root) {
+		scene_root->remove_child(old_scene);
+	}
+
 	if (Popup *p = Object::cast_to<Popup>(new_scene)) {
 		p->show();
 	}
@@ -4154,25 +4155,48 @@ HashMap<StringName, Variant> EditorNode::get_modified_properties_for_node(Node *
 	p_node->get_property_list(&pinfo);
 	for (const PropertyInfo &E : pinfo) {
 		if (E.usage & PROPERTY_USAGE_STORAGE) {
+			bool node_reference = (E.type == Variant::OBJECT && E.hint == PROPERTY_HINT_NODE_TYPE);
+			if (p_node_references_only && !node_reference) {
+				continue;
+			}
 			bool is_valid_revert = false;
 			Variant revert_value = EditorPropertyRevert::get_property_revert_value(p_node, E.name, &is_valid_revert);
 			Variant current_value = p_node->get(E.name);
 			if (is_valid_revert) {
 				if (PropertyUtils::is_property_value_different(p_node, current_value, revert_value)) {
 					// If this property is a direct node reference, save a NodePath instead to prevent corrupted references.
-					if (E.type == Variant::OBJECT && E.hint == PROPERTY_HINT_NODE_TYPE) {
+					if (node_reference) {
 						Node *target_node = Object::cast_to<Node>(current_value);
 						if (target_node) {
 							modified_property_map[E.name] = p_node->get_path_to(target_node);
 						}
 					} else {
-						if (!p_node_references_only) {
 						modified_property_map[E.name] = current_value;
 					}
 				}
 			}
 		}
 	}
+
+	return modified_property_map;
+}
+
+HashMap<StringName, Variant> EditorNode::get_modified_properties_reference_to_nodes(Node *p_node, List<Node *> &p_nodes_referenced_by) {
+	HashMap<StringName, Variant> modified_property_map;
+
+	List<PropertyInfo> pinfo;
+	p_node->get_property_list(&pinfo);
+	for (const PropertyInfo &E : pinfo) {
+		if (E.usage & PROPERTY_USAGE_STORAGE) {
+			if (E.type != Variant::OBJECT || E.hint != PROPERTY_HINT_NODE_TYPE) {
+				continue;
+			}
+			Variant current_value = p_node->get(E.name);
+			Node *target_node = Object::cast_to<Node>(current_value);
+			if (target_node && p_nodes_referenced_by.find(target_node)) {
+				modified_property_map[E.name] = p_node->get_path_to(target_node);
+			}
+		}
 	}
 
 	return modified_property_map;
@@ -4264,28 +4288,6 @@ void EditorNode::update_node_from_node_modification_entry(Node *p_node, Modifica
 	}
 }
 
-void EditorNode::update_node_reference_modification_table_for_node(
-		Node *p_root,
-		Node *p_node,
-		List<Node *> p_excluded_nodes,
-		HashMap<NodePath, ModificationNodeEntry> &p_modification_table) {
-	if (!p_excluded_nodes.find(p_node)) {
-		HashMap<StringName, Variant> modified_properties = get_modified_properties_for_node(p_node, false);
-
-		if (!modified_properties.is_empty()) {
-			ModificationNodeEntry modification_node_entry;
-			modification_node_entry.property_table = modified_properties;
-
-			p_modification_table[p_root->get_path_to(p_node)] = modification_node_entry;
-		}
-
-		for (int i = 0; i < p_node->get_child_count(); i++) {
-			Node *child = p_node->get_child(i);
-			update_node_reference_modification_table_for_node(p_root, child, p_excluded_nodes, p_modification_table);
-		}
-	}
-}
-
 bool EditorNode::is_additional_node_in_scene(Node *p_edited_scene, Node *p_reimported_root, Node *p_node) {
 	if (p_node == p_reimported_root) {
 		return false;
@@ -4328,11 +4330,39 @@ bool EditorNode::is_additional_node_in_scene(Node *p_edited_scene, Node *p_reimp
 void EditorNode::get_preload_scene_modification_table(
 		Node *p_edited_scene,
 		Node *p_reimported_root,
-		Node *p_node, HashMap<NodePath, ModificationNodeEntry> &p_modification_table) {
+		Node *p_node, InstanceModificationsEntry &p_instance_modifications) {
-	// Only take the nodes that are in the base imported scene. The additional nodes will be managed
+	if (is_additional_node_in_scene(p_edited_scene, p_reimported_root, p_node)) {
-	// after the resources are reimported. It's not important to check which property has
+		// Only save additional nodes which have an owner since this was causing issues transient ownerless nodes
-	// changed on nodes that will not be reimported because they are not part of the reimported scene.
+		// which get recreated upon scene tree entry.
-	if (!is_additional_node_in_scene(p_edited_scene, p_reimported_root, p_node)) {
+		// For now instead, assume all ownerless nodes are transient and will have to be recreated.
+		if (p_node->get_owner()) {
+			HashMap<StringName, Variant> modified_properties = get_modified_properties_for_node(p_node, true);
+			if (p_node->get_owner() == p_edited_scene) {
+				AdditiveNodeEntry new_additive_node_entry;
+				new_additive_node_entry.node = p_node;
+				new_additive_node_entry.parent = p_reimported_root->get_path_to(p_node->get_parent());
+				new_additive_node_entry.owner = p_node->get_owner();
+				new_additive_node_entry.index = p_node->get_index();
+
+				Node2D *node_2d = Object::cast_to<Node2D>(p_node);
+				if (node_2d) {
+					new_additive_node_entry.transform_2d = node_2d->get_transform();
+				}
+				Node3D *node_3d = Object::cast_to<Node3D>(p_node);
+				if (node_3d) {
+					new_additive_node_entry.transform_3d = node_3d->get_transform();
+				}
+
+				p_instance_modifications.addition_list.push_back(new_additive_node_entry);
+			}
+			if (!modified_properties.is_empty()) {
+				ModificationNodeEntry modification_node_entry;
+				modification_node_entry.property_table = modified_properties;
+
+				p_instance_modifications.modifications[p_reimported_root->get_path_to(p_node)] = modification_node_entry;
+			}
+		}
+	} else {
 		HashMap<StringName, Variant> modified_properties = get_modified_properties_for_node(p_node, false);
 
 		// Find all valid connections to other nodes.
@@ -4391,58 +4421,42 @@ void EditorNode::get_preload_scene_modification_table(
 			modification_node_entry.connections_from = valid_connections_from;
 			modification_node_entry.groups = groups;
 
-			p_modification_table[p_reimported_root->get_path_to(p_node)] = modification_node_entry;
+			p_instance_modifications.modifications[p_reimported_root->get_path_to(p_node)] = modification_node_entry;
 		}
 	}
 
 	for (int i = 0; i < p_node->get_child_count(); i++) {
-		Node *child = p_node->get_child(i);
+		get_preload_scene_modification_table(p_edited_scene, p_reimported_root, p_node->get_child(i), p_instance_modifications);
-		get_preload_scene_modification_table(p_edited_scene, p_reimported_root, child, p_modification_table);
 	}
 }
 
-void EditorNode::update_reimported_diff_data_for_additional_nodes(
+void EditorNode::get_preload_modifications_reference_to_nodes(
-		Node *p_edited_scene,
+		Node *p_root,
-		Node *p_reimported_root,
 		Node *p_node,
-		HashMap<NodePath, ModificationNodeEntry> &p_modification_table,
+		List<Node *> &p_excluded_nodes,
-		List<AdditiveNodeEntry> &p_addition_list) {
+		List<Node *> &p_instance_list_with_children,
-	if (is_additional_node_in_scene(p_edited_scene, p_reimported_root, p_node)) {
+		HashMap<NodePath, ModificationNodeEntry> &p_modification_table) {
-		// Only save additional nodes which have an owner since this was causing issues transient ownerless nodes
+	if (!p_excluded_nodes.find(p_node)) {
-		// which get recreated upon scene tree entry.
+		HashMap<StringName, Variant> modified_properties = get_modified_properties_reference_to_nodes(p_node, p_instance_list_with_children);
-		// For now instead, assume all ownerless nodes are transient and will have to be recreated.
-		if (p_node->get_owner()) {
-			HashMap<StringName, Variant> modified_properties = get_modified_properties_for_node(p_node, true);
-			if (p_node->get_owner() == p_edited_scene) {
-				AdditiveNodeEntry new_additive_node_entry;
-				new_additive_node_entry.node = p_node;
-				new_additive_node_entry.parent = p_reimported_root->get_path_to(p_node->get_parent());
-				new_additive_node_entry.owner = p_node->get_owner();
-				new_additive_node_entry.index = p_node->get_index();
 
-				Node2D *node_2d = Object::cast_to<Node2D>(p_node);
-				if (node_2d) {
-					new_additive_node_entry.transform_2d = node_2d->get_relative_transform_to_parent(node_2d->get_parent());
-				}
-				Node3D *node_3d = Object::cast_to<Node3D>(p_node);
-				if (node_3d) {
-					new_additive_node_entry.transform_3d = node_3d->get_relative_transform(node_3d->get_parent());
-				}
-
-				p_addition_list.push_back(new_additive_node_entry);
-			}
 		if (!modified_properties.is_empty()) {
 			ModificationNodeEntry modification_node_entry;
 			modification_node_entry.property_table = modified_properties;
 
-				p_modification_table[p_reimported_root->get_path_to(p_node)] = modification_node_entry;
+			p_modification_table[p_root->get_path_to(p_node)] = modification_node_entry;
-			}
-		}
 		}
 
+		for (int i = 0; i < p_node->get_child_count(); i++) {
+			get_preload_modifications_reference_to_nodes(p_root, p_node->get_child(i), p_excluded_nodes, p_instance_list_with_children, p_modification_table);
+		}
+	}
+}
+
+void EditorNode::get_children_nodes(Node *p_node, List<Node *> &p_nodes) {
 	for (int i = 0; i < p_node->get_child_count(); i++) {
 		Node *child = p_node->get_child(i);
-		update_reimported_diff_data_for_additional_nodes(p_edited_scene, p_reimported_root, child, p_modification_table, p_addition_list);
+		p_nodes.push_back(child);
+		get_children_nodes(child, p_nodes);
 	}
 }
 
@@ -4456,8 +4470,7 @@ void EditorNode::replace_history_reimported_nodes(Node *p_original_root_node, No
 	}
 
 	for (int i = 0; i < p_node->get_child_count(); i++) {
-		Node *child = p_node->get_child(i);
+		replace_history_reimported_nodes(p_original_root_node, p_new_root_node, p_node->get_child(i));
-		replace_history_reimported_nodes(p_original_root_node, p_new_root_node, child);
 	}
 }
 
@@ -5831,25 +5844,6 @@ void EditorNode::reload_scene(const String &p_path) {
 	scene_tabs->set_current_tab(current_tab);
 }
 
-void EditorNode::get_edited_scene_map(const String &p_instance_path, HashMap<int, List<Node *>> &p_edited_scene_map) {
-	// Walk through each opened scene to get a global list of all instances which match
-	// the current reimported scenes.
-	for (int i = 0; i < editor_data.get_edited_scene_count(); i++) {
-		if (editor_data.get_scene_path(i) == p_instance_path) {
-			continue;
-		}
-		Node *edited_scene_root = editor_data.get_edited_scene_root(i);
-
-		if (edited_scene_root) {
-			List<Node *> valid_nodes;
-			find_all_instances_inheriting_path_in_node(edited_scene_root, edited_scene_root, p_instance_path, valid_nodes);
-			if (valid_nodes.size() > 0) {
-				p_edited_scene_map[i] = valid_nodes;
-			}
-		}
-	}
-}
-
 void EditorNode::find_all_instances_inheriting_path_in_node(Node *p_root, Node *p_node, const String &p_instance_path, List<Node *> &p_instance_list) {
 	String scene_file_path = p_node->get_scene_file_path();
 
@@ -5872,61 +5866,70 @@ void EditorNode::find_all_instances_inheriting_path_in_node(Node *p_root, Node *
 	}
 
 	for (int i = 0; i < p_node->get_child_count(); i++) {
-		Node *child = p_node->get_child(i);
+		find_all_instances_inheriting_path_in_node(p_root, p_node->get_child(i), p_instance_path, p_instance_list);
-		find_all_instances_inheriting_path_in_node(p_root, child, p_instance_path, p_instance_list);
 	}
 }
 
 void EditorNode::preload_reimporting_with_path_in_edited_scenes(const String &p_instance_path) {
-	HashMap<int, List<Node *>> edited_scene_map;
 	scenes_modification_table.clear();
 
-	get_edited_scene_map(p_instance_path, edited_scene_map);
+	EditorProgress progress("preload_reimporting_scene", TTR("Preparing scenes for reload"), editor_data.get_edited_scene_count());
-
-	if (edited_scene_map.size() > 0) {
-		scenes_modification_table.clear();
 
 	int original_edited_scene_idx = editor_data.get_edited_scene();
-		Node *original_edited_scene_root = editor_data.get_edited_scene_root();
 
-		// Prevent scene roots with the same name from being in the tree at the same time.
+	// Walk through each opened scene to get a global list of all instances which match
-		scene_root->remove_child(original_edited_scene_root);
+	// the current reimported scenes.
+	for (int current_scene_idx = 0; current_scene_idx < editor_data.get_edited_scene_count(); current_scene_idx++) {
+		progress.step(vformat(TTR("Analyzing scene %s"), editor_data.get_scene_title(current_scene_idx)), current_scene_idx);
 
-		for (const KeyValue<int, List<Node *>> &edited_scene_map_elem : edited_scene_map) {
+		if (editor_data.get_scene_path(current_scene_idx) == p_instance_path) {
-			// Set the current scene.
+			continue;
-			int current_scene_idx = edited_scene_map_elem.key;
+		}
+		Node *edited_scene_root = editor_data.get_edited_scene_root(current_scene_idx);
+
+		if (edited_scene_root) {
+			List<Node *> instance_list;
+			find_all_instances_inheriting_path_in_node(edited_scene_root, edited_scene_root, p_instance_path, instance_list);
+			if (instance_list.size() > 0) {
+				SceneModificationsEntry scene_motifications;
 				editor_data.set_edited_scene(current_scene_idx);
-			Node *current_edited_scene = editor_data.get_edited_scene_root(current_scene_idx);
 
-			// Make sure the node is in the tree so that editor_selection can add node smoothly.
+				List<Node *> instance_list_with_children;
-			scene_root->add_child(current_edited_scene);
+				for (Node *original_node : instance_list) {
+					InstanceModificationsEntry instance_modifications;
 
-			for (Node *original_node : edited_scene_map_elem.value) {
 					// Fetching all the modified properties of the nodes reimported scene.
-				HashMap<NodePath, ModificationNodeEntry> modification_table;
+					get_preload_scene_modification_table(edited_scene_root, original_node, original_node, instance_modifications);
-				get_preload_scene_modification_table(current_edited_scene, original_node, original_node, modification_table);
 
-				if (modification_table.size() > 0) {
+					instance_modifications.original_node = original_node;
-					NodePath scene_path_to_node = current_edited_scene->get_path_to(original_node);
+					scene_motifications.instance_list.push_back(instance_modifications);
-					scenes_modification_table[current_scene_idx][scene_path_to_node] = modification_table;
+
-				}
+					instance_list_with_children.push_back(original_node);
+					get_children_nodes(original_node, instance_list_with_children);
 				}
 
-			scene_root->remove_child(current_edited_scene);
+				// Search the scene to find nodes that references the nodes will be recreated.
+				get_preload_modifications_reference_to_nodes(edited_scene_root, edited_scene_root, instance_list, instance_list_with_children, scene_motifications.other_instances_modifications);
+
+				scenes_modification_table[current_scene_idx] = scene_motifications;
+			}
+		}
 	}
 
 	editor_data.set_edited_scene(original_edited_scene_idx);
-		scene_root->add_child(original_edited_scene_root);
+
-	}
+	progress.step(TTR("Preparation done."), editor_data.get_edited_scene_count());
 }
 
 void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_instance_path) {
-	HashMap<int, List<Node *>> edited_scene_map;
+	if (scenes_modification_table.size() == 0) {
+		return;
+	}
 	Array replaced_nodes;
 
-	get_edited_scene_map(p_instance_path, edited_scene_map);
+	EditorProgress progress("reloading_scene", TTR("Scenes reloading"), editor_data.get_edited_scene_count());
+	progress.step(TTR("Reloading..."), 0, true);
 
-	if (edited_scene_map.size() > 0) {
 	// Reload the new instance.
 	Error err;
 	Ref<PackedScene> instance_scene_packed_scene = ResourceLoader::load(p_instance_path, "", ResourceFormatLoader::CACHE_MODE_REPLACE, &err);
@@ -5943,19 +5946,24 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 	editor_selection->clear();
 
 	int original_edited_scene_idx = editor_data.get_edited_scene();
-		Node *original_edited_scene_root = editor_data.get_edited_scene_root();
 
-		// Prevent scene roots with the same name from being in the tree at the same time.
+	for (KeyValue<int, SceneModificationsEntry> &scene_modifications_elem : scenes_modification_table) {
-		scene_root->remove_child(original_edited_scene_root);
-
-		for (const KeyValue<int, List<Node *>> &edited_scene_map_elem : edited_scene_map) {
 		// Set the current scene.
-			int current_scene_idx = edited_scene_map_elem.key;
+		int current_scene_idx = scene_modifications_elem.key;
+		SceneModificationsEntry *scene_modifications = &scene_modifications_elem.value;
+
 		editor_data.set_edited_scene(current_scene_idx);
 		Node *current_edited_scene = editor_data.get_edited_scene_root(current_scene_idx);
 
 		// Make sure the node is in the tree so that editor_selection can add node smoothly.
+		if (original_edited_scene_idx != current_scene_idx) {
+			// Prevent scene roots with the same name from being in the tree at the same time.
+			Node *original_edited_scene_root = editor_data.get_edited_scene_root(original_edited_scene_idx);
+			if (original_edited_scene_root && original_edited_scene_root->get_name() == current_edited_scene->get_name()) {
+				scene_root->remove_child(original_edited_scene_root);
+			}
 			scene_root->add_child(current_edited_scene);
+		}
 
 		// Restore the state so that the selection can be updated.
 		editor_state = editor_data.restore_edited_scene_state(editor_selection, &editor_history);
@@ -5969,11 +5977,8 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 		// Update the version
 		editor_data.is_scene_changed(current_scene_idx);
 
-			// Contains modifications in the edited scene which reference nodes inside of any nodes we will be reimporting.
+		for (InstanceModificationsEntry instance_modifications : scene_modifications->instance_list) {
-			HashMap<NodePath, ModificationNodeEntry> edited_scene_global_modification_table;
+			Node *original_node = instance_modifications.original_node;
-			update_node_reference_modification_table_for_node(current_edited_scene, current_edited_scene, edited_scene_map_elem.value, edited_scene_global_modification_table);
-
-			for (Node *original_node : edited_scene_map_elem.value) {
 			String original_node_file_path = original_node->get_scene_file_path();
 
 			// Load a replacement scene for the node.
@@ -6064,17 +6069,8 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 			}
 			ERR_FAIL_NULL(instantiated_node);
 
-				// Walk the tree for the current node and extract relevant diff data, storing it in the modification table.
-				// For additional nodes which are part of the current scene, they get added to the addition table.
-				HashMap<NodePath, ModificationNodeEntry> modification_table;
-				List<AdditiveNodeEntry> addition_list;
-				if (scenes_modification_table.has(current_scene_idx) && scenes_modification_table[current_scene_idx].has(scene_path_to_node)) {
-					modification_table = scenes_modification_table[current_scene_idx][scene_path_to_node];
-				}
-				update_reimported_diff_data_for_additional_nodes(current_edited_scene, original_node, original_node, modification_table, addition_list);
-
 			// Disconnect all relevant connections, all connections from and persistent connections to.
-				for (const KeyValue<NodePath, ModificationNodeEntry> &modification_table_entry : modification_table) {
+			for (const KeyValue<NodePath, ModificationNodeEntry> &modification_table_entry : instance_modifications.modifications) {
 				for (Connection conn : modification_table_entry.value.connections_from) {
 					conn.signal.get_object()->disconnect(conn.signal.get_name(), conn.callable);
 				}
@@ -6096,7 +6092,7 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 			}
 
 			// Remove all nodes which were added as additional elements (they will be restored later).
-				for (AdditiveNodeEntry additive_node_entry : addition_list) {
+			for (AdditiveNodeEntry additive_node_entry : instance_modifications.addition_list) {
 				Node *addition_node = additive_node_entry.node;
 				addition_node->get_parent()->remove_child(addition_node);
 			}
@@ -6146,6 +6142,16 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 				instantiated_node->set_scene_file_path(original_node_file_path);
 				current_edited_scene = instantiated_node;
 				editor_data.set_edited_scene_root(current_edited_scene);
+
+				if (original_edited_scene_idx == current_scene_idx) {
+					// How that the editor executes a redraw while destroying or progressing the EditorProgress,
+					// it crashes when the root scene has been replaced because the edited scene
+					// was freed and no longer in the scene tree.
+					SceneTreeDock::get_singleton()->set_edited_scene(current_edited_scene);
+					if (get_tree()) {
+						get_tree()->set_edited_scene_root(current_edited_scene);
+					}
+				}
 			}
 
 			// Replace the original node with the instantiated version.
@@ -6168,7 +6174,7 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 			}
 
 			// Attempt to re-add all the additional nodes.
-				for (AdditiveNodeEntry additive_node_entry : addition_list) {
+			for (AdditiveNodeEntry additive_node_entry : instance_modifications.addition_list) {
 				Node *parent_node = instantiated_node->get_node_or_null(additive_node_entry.parent);
 
 				if (!parent_node) {
@@ -6210,7 +6216,7 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 			}
 
 			// Attempt to restore the modified properties and signals for the instantitated node and all its owned children.
-				for (KeyValue<NodePath, ModificationNodeEntry> &E : modification_table) {
+			for (KeyValue<NodePath, ModificationNodeEntry> &E : instance_modifications.modifications) {
 				NodePath new_current_path = E.key;
 				Node *modifiable_node = instantiated_node->get_node_or_null(new_current_path);
 
@@ -6221,7 +6227,7 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 		}
 
 		// Attempt to restore the modified properties and signals for the instantitated node and all its owned children.
-			for (KeyValue<NodePath, ModificationNodeEntry> &E : edited_scene_global_modification_table) {
+		for (KeyValue<NodePath, ModificationNodeEntry> &E : scene_modifications->other_instances_modifications) {
 			NodePath new_current_path = E.key;
 			Node *modifiable_node = current_edited_scene->get_node_or_null(new_current_path);
 
@@ -6241,24 +6247,30 @@ void EditorNode::reload_instances_with_path_in_edited_scenes(const String &p_ins
 		// Cleanup the history of the changes.
 		editor_history.cleanup_history();
 
+		if (original_edited_scene_idx != current_scene_idx) {
 			scene_root->remove_child(current_edited_scene);
+
+			// Ensure the current edited scene is re-added if removed earlier because it has the same name
+			// as the reimported scene. The editor could crash when reloading SceneTreeDock if the current
+			// edited scene is not in the scene tree.
+			Node *original_edited_scene_root = editor_data.get_edited_scene_root(original_edited_scene_idx);
+			if (original_edited_scene_root && !original_edited_scene_root->get_parent()) {
+				scene_root->add_child(original_edited_scene_root);
+			}
+		}
 	}
 
 	// For the whole editor, call the _notify_nodes_scene_reimported with a list of replaced nodes.
 	// To inform anything that depends on them that they should update as appropriate.
 	_notify_nodes_scene_reimported(this, replaced_nodes);
 
-		edited_scene_map.clear();
-
 	editor_data.set_edited_scene(original_edited_scene_idx);
 
-		original_edited_scene_root = editor_data.get_edited_scene_root();
-		scene_root->add_child(original_edited_scene_root);
-
 	editor_data.restore_edited_scene_state(editor_selection, &editor_history);
-	}
 
 	scenes_modification_table.clear();
+
+	progress.step(TTR("Reloading done."), editor_data.get_edited_scene_count());
 }
 
 void EditorNode::_remove_all_not_owned_children(Node *p_node, Node *p_owner) {

editor/editor_node.h

@@ -797,6 +797,7 @@ public:
 	Error load_resource(const String &p_resource, bool p_ignore_broken_deps = false);
 
 	HashMap<StringName, Variant> get_modified_properties_for_node(Node *p_node, bool p_node_references_only);
+	HashMap<StringName, Variant> get_modified_properties_reference_to_nodes(Node *p_node, List<Node *> &p_nodes_referenced_by);
 
 	struct AdditiveNodeEntry {
 		Node *node = nullptr;
@@ -820,27 +821,34 @@ public:
 		List<Node::GroupInfo> groups;
 	};
 
-	HashMap<int, HashMap<NodePath, HashMap<NodePath, ModificationNodeEntry>>> scenes_modification_table;
+	struct InstanceModificationsEntry {
+		Node *original_node;
+		List<Node *> instance_list;
+		HashMap<NodePath, ModificationNodeEntry> modifications;
+		List<AdditiveNodeEntry> addition_list;
+	};
+
+	struct SceneModificationsEntry {
+		List<InstanceModificationsEntry> instance_list;
+		HashMap<NodePath, ModificationNodeEntry> other_instances_modifications;
+	};
+
+	HashMap<int, SceneModificationsEntry> scenes_modification_table;
 
 	void update_node_from_node_modification_entry(Node *p_node, ModificationNodeEntry &p_node_modification);
 
-	void update_node_reference_modification_table_for_node(
-			Node *p_root,
-			Node *p_node,
-			List<Node *> p_excluded_nodes,
-			HashMap<NodePath, ModificationNodeEntry> &p_modification_table);
-
 	void get_preload_scene_modification_table(
 			Node *p_edited_scene,
 			Node *p_reimported_root,
-			Node *p_node, HashMap<NodePath, ModificationNodeEntry> &p_modification_table);
+			Node *p_node, InstanceModificationsEntry &p_instance_modifications);
 
-	void update_reimported_diff_data_for_additional_nodes(
+	void get_preload_modifications_reference_to_nodes(
-			Node *p_edited_scene,
+			Node *p_root,
-			Node *p_reimported_root,
 			Node *p_node,
-			HashMap<NodePath, ModificationNodeEntry> &p_modification_table,
+			List<Node *> &p_excluded_nodes,
-			List<AdditiveNodeEntry> &p_addition_list);
+			List<Node *> &p_instance_list_with_children,
+			HashMap<NodePath, ModificationNodeEntry> &p_modification_table);
+	void get_children_nodes(Node *p_node, List<Node *> &p_nodes);
 	bool is_additional_node_in_scene(Node *p_edited_scene, Node *p_reimported_root, Node *p_node);
 
 	void replace_history_reimported_nodes(Node *p_original_root_node, Node *p_new_root_node, Node *p_node);
@@ -898,7 +906,6 @@ public:
 
 	void reload_scene(const String &p_path);
 
-	void get_edited_scene_map(const String &p_instance_path, HashMap<int, List<Node *>> &p_edited_scene_map);
 	void find_all_instances_inheriting_path_in_node(Node *p_root, Node *p_node, const String &p_instance_path, List<Node *> &p_instance_list);
 	void preload_reimporting_with_path_in_edited_scenes(const String &p_path);
 	void reload_instances_with_path_in_edited_scenes(const String &p_path);