Add the ability to expose nodes for direct access in instantiated scenes

doc/classes/Node.xml

@@ -982,6 +982,9 @@
 		<member name="editor_description" type="String" setter="set_editor_description" getter="get_editor_description" default="&quot;&quot;">
 			An optional description to the node. It will be displayed as a tooltip when hovering over the node in the editor's Scene dock.
 		</member>
+		<member name="exposed_in_owner" type="bool" setter="set_exposed_in_owner" getter="is_exposed_in_owner" default="false">
+			Sets this node's state as an exposed node in its [member owner]. This allows the node to be accessed in the editor when the scene is instantiated in another. It also enforces that the node is unique, see [member unique_name_in_owner].
+		</member>
 		<member name="multiplayer" type="MultiplayerAPI" setter="" getter="get_multiplayer">
 			The [MultiplayerAPI] instance associated with this node. See [method SceneTree.get_multiplayer].
 			[b]Note:[/b] Renaming the node, or moving it in the tree, will not move the [MultiplayerAPI] to the new path, you will have to update this manually.

editor/editor_data.cpp

@@ -730,6 +730,9 @@ bool EditorData::check_and_update_scene(int p_idx) {
 			}
 		}
 
+		// Apply Overrides when instanced scene gets updated.
+		pscene->get_state()->apply_overrides(new_scene);
+
 		new_scene->set_scene_file_path(edited_scene[p_idx].root->get_scene_file_path());
 		Node *old_root = edited_scene[p_idx].root;
 		EditorNode::get_singleton()->set_edited_scene(new_scene);

editor/editor_node.cpp

@@ -4193,6 +4193,8 @@ Error EditorNode::load_scene(const String &p_scene, bool p_ignore_broken_deps, b
 			}
 		}
 	}
+	// Apply Overrides when loading a scene.
+	sdata->get_state()->apply_overrides(new_scene);
 
 	if (!restoring_scenes) {
 		save_editor_layout_delayed();

editor/gui/scene_tree_editor.cpp

@@ -177,6 +177,17 @@ void SceneTreeEditor::_cell_button_pressed(Object *p_item, int p_column, int p_i
 		undo_redo->create_action(TTR("Disable Scene Unique Name"));
 		undo_redo->add_do_method(n, "set_unique_name_in_owner", false);
 		undo_redo->add_undo_method(n, "set_unique_name_in_owner", true);
+		if (n->is_exposed_in_owner()) {
+			undo_redo->add_do_method(n, "set_exposed_in_owner", false);
+			undo_redo->add_undo_method(n, "set_exposed_in_owner", true);
+		}
+		undo_redo->add_do_method(this, "_update_tree");
+		undo_redo->add_undo_method(this, "_update_tree");
+		undo_redo->commit_action();
+	} else if (p_id == BUTTON_EXPOSED) {
+		undo_redo->create_action(TTR("Disable Scene Exposed Node"));
+		undo_redo->add_do_method(n, "set_exposed_in_owner", false);
+		undo_redo->add_undo_method(n, "set_exposed_in_owner", true);
 		undo_redo->add_do_method(this, "_update_tree");
 		undo_redo->add_undo_method(this, "_update_tree");
 		undo_redo->commit_action();
@@ -203,9 +214,14 @@ void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
 	bool part_of_subscene = false;
 
 	if (!display_foreign && p_node->get_owner() != get_scene_node() && p_node != get_scene_node()) {
-		if ((show_enabled_subscene || can_open_instance) && p_node->get_owner() && (get_scene_node()->is_editable_instance(p_node->get_owner()))) {
+		if (((show_enabled_subscene || can_open_instance) && p_node->get_owner() && (get_scene_node()->is_editable_instance(p_node->get_owner()))) || (p_node->get_owner() != get_scene_node() && p_node->is_exposed_in_owner())) {
 			part_of_subscene = true;
 			//allow
+		} else if (p_node->has_exposed_nodes(true)) {
+			for (int i = 0; i < p_node->get_child_count(); i++) {
+				_add_nodes(p_node->get_child(i), p_parent);
+			}
+			return;
 		} else {
 			return;
 		}
@@ -217,7 +233,7 @@ void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
 
 	item->set_text(0, p_node->get_name());
 	item->set_text_overrun_behavior(0, TextServer::OVERRUN_NO_TRIMMING);
-	if (can_rename && !part_of_subscene) {
+	if (can_rename && !part_of_subscene && (!p_node->is_exposed_in_owner() || p_node->get_owner() == get_scene_node())) {
 		item->set_editable(0, true);
 	}
 
@@ -322,6 +338,13 @@ void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
 			item->add_button(0, get_editor_theme_icon(SNAME("SceneUniqueName")), BUTTON_UNIQUE, p_node->get_owner() != EditorNode::get_singleton()->get_edited_scene(), vformat(TTR("This node can be accessed from within anywhere in the scene by preceding it with the '%s' prefix in a node path.\nClick to disable this."), UNIQUE_NODE_PREFIX));
 		}
 
+		if (p_node->is_exposed_in_owner()) {
+			item->add_button(0, get_editor_theme_icon(SNAME("SceneExposedNode")), BUTTON_EXPOSED, p_node->get_owner() != EditorNode::get_singleton()->get_edited_scene(), TTR("This node will be exposed in the editor when this scene is instantiated.\nClick to disable this."));
+			if (p_node->get_owner() != get_scene_node()) {
+				_set_item_custom_color(item, get_theme_color(SNAME("warning_color"), EditorStringName(Editor)));
+			}
+		}
+
 		int num_connections = p_node->get_persistent_signal_connection_count();
 		int num_groups = p_node->get_persistent_group_count();
 

editor/gui/scene_tree_editor.h

@@ -55,6 +55,7 @@ class SceneTreeEditor : public Control {
 		BUTTON_GROUPS = 7,
 		BUTTON_PIN = 8,
 		BUTTON_UNIQUE = 9,
+		BUTTON_EXPOSED = 10,
 	};
 
 	Tree *tree = nullptr;

editor/import/3d/resource_importer_scene.cpp

@@ -1024,6 +1024,11 @@ Node *ResourceImporterScene::_pre_fix_node(Node *p_node, Node *p_root, HashMap<R
 		}
 	}
 
+	if (!isroot && _teststr(name, "exp")) {
+		p_node->set_exposed_in_owner(true);
+		p_node->set_name(_fixstr(name, "exp"));
+	}
+
 	return p_node;
 }
 
@@ -1766,6 +1771,10 @@ Node *ResourceImporterScene::_post_fix_node(Node *p_node, Node *p_root, HashMap<
 		}
 	}
 
+	if (node_settings.has("import/exposed_in_owner")) {
+		p_node->set_exposed_in_owner(node_settings["import/exposed_in_owner"].operator bool());
+	}
+
 	return p_node;
 }
 
@@ -1976,9 +1985,11 @@ void ResourceImporterScene::get_internal_import_options(InternalImportCategory p
 	switch (p_category) {
 		case INTERNAL_IMPORT_CATEGORY_NODE: {
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/skip_import", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
+			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/exposed_in_owner", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
 		} break;
 		case INTERNAL_IMPORT_CATEGORY_MESH_3D_NODE: {
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/skip_import", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
+			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/exposed_in_owner", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "generate/physics", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::INT, "generate/navmesh", PROPERTY_HINT_ENUM, "Disabled,Mesh + NavMesh,NavMesh Only"), 0));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::INT, "physics/body_type", PROPERTY_HINT_ENUM, "Static,Dynamic,Area"), 0));
@@ -2057,6 +2068,7 @@ void ResourceImporterScene::get_internal_import_options(InternalImportCategory p
 		} break;
 		case INTERNAL_IMPORT_CATEGORY_ANIMATION_NODE: {
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/skip_import", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
+			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/exposed_in_owner", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "optimizer/enabled", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), true));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::FLOAT, "optimizer/max_velocity_error", PROPERTY_HINT_RANGE, "0,1,0.01"), 0.01));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::FLOAT, "optimizer/max_angular_error", PROPERTY_HINT_RANGE, "0,1,0.01"), 0.01));
@@ -2069,6 +2081,7 @@ void ResourceImporterScene::get_internal_import_options(InternalImportCategory p
 		} break;
 		case INTERNAL_IMPORT_CATEGORY_SKELETON_3D_NODE: {
 			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/skip_import", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
+			r_options->push_back(ImportOption(PropertyInfo(Variant::BOOL, "import/exposed_in_owner", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), false));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::INT, "rest_pose/load_pose", PROPERTY_HINT_ENUM, "Default Pose,Use AnimationPlayer,Load External Animation", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), 0));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::OBJECT, "rest_pose/external_animation_library", PROPERTY_HINT_RESOURCE_TYPE, "Animation,AnimationLibrary", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), Variant()));
 			r_options->push_back(ImportOption(PropertyInfo(Variant::STRING, "rest_pose/selected_animation", PROPERTY_HINT_ENUM, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_UPDATE_ALL_IF_MODIFIED), ""));
@@ -2615,6 +2628,7 @@ Node *ResourceImporterScene::_generate_meshes(Node *p_node, const Dictionary &p_
 			} break;
 		}
 
+		mesh_node->set_exposed_in_owner(src_mesh_node->is_exposed_in_owner());
 		mesh_node->set_layer_mask(src_mesh_node->get_layer_mask());
 		mesh_node->set_cast_shadows_setting(src_mesh_node->get_cast_shadows_setting());
 		mesh_node->set_visibility_range_begin(src_mesh_node->get_visibility_range_begin());

editor/scene_tree_dock.cpp

@@ -208,6 +208,8 @@ void SceneTreeDock::shortcut_input(const Ref<InputEvent> &p_event) {
 		_tool_selected(TOOL_SHOW_IN_FILE_SYSTEM);
 	} else if (ED_IS_SHORTCUT("scene_tree/toggle_unique_name", p_event)) {
 		_tool_selected(TOOL_TOGGLE_SCENE_UNIQUE_NAME);
+	} else if (ED_IS_SHORTCUT("scene_tree/toggle_exposed_node", p_event)) {
+		_tool_selected(TOOL_TOGGLE_SCENE_EXPOSED);
 	} else if (ED_IS_SHORTCUT("scene_tree/toggle_editable_children", p_event)) {
 		_tool_selected(TOOL_SCENE_EDITABLE_CHILDREN);
 	} else if (ED_IS_SHORTCUT("scene_tree/delete", p_event)) {
@@ -1424,6 +1426,82 @@ void SceneTreeDock::_tool_selected(int p_tool, bool p_confirm_override) {
 					}
 					undo_redo->add_do_method(node, "set_unique_name_in_owner", false);
 					undo_redo->add_undo_method(node, "set_unique_name_in_owner", true);
+					if (node->is_exposed_in_owner()) {
+						undo_redo->add_undo_method(node, "set_exposed_in_owner", true);
+					}
+				}
+				undo_redo->commit_action();
+			}
+		} break;
+		case TOOL_TOGGLE_SCENE_EXPOSED: {
+			// Enabling/disabling based on the same node based on which the checkbox in the menu is checked/unchecked.
+			List<Node *>::Element *first_selected = editor_selection->get_selected_node_list().front();
+			if (first_selected == nullptr) {
+				return;
+			}
+			if (first_selected->get() == EditorNode::get_singleton()->get_edited_scene()) {
+				// Exclude Root Node. It should never be unique name in its own scene!
+				editor_selection->remove_node(first_selected->get());
+				first_selected = editor_selection->get_selected_node_list().front();
+				if (first_selected == nullptr) {
+					return;
+				}
+			}
+			bool enabling = !first_selected->get()->is_exposed_in_owner();
+
+			List<Node *> full_selection = editor_selection->get_full_selected_node_list();
+			EditorUndoRedoManager *undo_redo = EditorUndoRedoManager::get_singleton();
+
+			if (enabling) {
+				Vector<Node *> new_exposed_nodes;
+				Vector<StringName> new_unique_names;
+				Vector<StringName> cant_be_set_unique_names;
+
+				for (Node *node : full_selection) {
+					if (node->is_exposed_in_owner()) {
+						continue;
+					}
+					if (node->get_owner() != get_tree()->get_edited_scene_root()) {
+						continue;
+					}
+
+					StringName name = node->get_name();
+					Node *unique_node = get_tree()->get_edited_scene_root()->get_node_or_null(UNIQUE_NODE_PREFIX + String(name));
+					if (new_unique_names.has(name) || (unique_node != nullptr && unique_node != this && unique_node->is_exposed_in_owner())) {
+						cant_be_set_unique_names.push_back(name);
+					} else {
+						new_exposed_nodes.push_back(node);
+						new_unique_names.push_back(name);
+					}
+				}
+				if (new_exposed_nodes.size()) {
+					undo_redo->create_action(TTR("Enable Exposed Node(s)"));
+					for (Node *node : new_exposed_nodes) {
+						if (!node->is_unique_name_in_owner()) {
+							undo_redo->add_undo_method(node, "set_unique_name_in_owner", false);
+						}
+						undo_redo->add_do_method(node, "set_exposed_in_owner", true);
+						undo_redo->add_undo_method(node, "set_exposed_in_owner", false);
+					}
+					undo_redo->commit_action();
+				}
+				if (cant_be_set_unique_names.size()) {
+					String popup_text = TTR("Unique names already used by another node in the scene:");
+					popup_text += "\n";
+					for (const StringName &name : cant_be_set_unique_names) {
+						popup_text += "\n" + String(name);
+					}
+					accept->set_text(popup_text);
+					accept->popup_centered();
+				}
+			} else { // Disabling.
+				undo_redo->create_action(TTR("Disable Exposed Node(s)"));
+				for (Node *node : full_selection) {
+					if (!node->is_unique_name_in_owner()) {
+						continue;
+					}
+					undo_redo->add_do_method(node, "set_exposed_in_owner", false);
+					undo_redo->add_undo_method(node, "set_exposed_in_owner", true);
 				}
 				undo_redo->commit_action();
 			}
@@ -2601,7 +2679,7 @@ void SceneTreeDock::_toggle_editable_children(Node *p_node) {
 		Array name_array;
 
 		for (Node *owned_node : owned) {
-			if (owned_node != p_node && owned_node != edited_scene && owned_node->get_owner() == edited_scene && owned_node->get_parent()->get_owner() != edited_scene) {
+			if (owned_node != p_node && owned_node != edited_scene && owned_node->get_owner() == edited_scene && owned_node->get_parent()->get_owner() != edited_scene && owned_node->is_exposed_in_owner()) {
 				owned_nodes_array.push_back(owned_node);
 				paths_array.push_back(p_node->get_path_to(owned_node->get_parent()));
 				name_array.push_back(owned_node->get_name());
@@ -3673,6 +3751,8 @@ void SceneTreeDock::_tree_rmb(const Vector2 &p_menu_pos) {
 			Node *node = full_selection.front()->get();
 			menu->add_icon_shortcut(get_editor_theme_icon(SNAME("SceneUniqueName")), ED_GET_SHORTCUT("scene_tree/toggle_unique_name"), TOOL_TOGGLE_SCENE_UNIQUE_NAME);
 			menu->set_item_text(menu->get_item_index(TOOL_TOGGLE_SCENE_UNIQUE_NAME), node->is_unique_name_in_owner() ? TTR("Revoke Unique Name") : TTR("Access as Unique Name"));
+			menu->add_icon_shortcut(get_editor_theme_icon(SNAME("SceneExposedNode")), ED_GET_SHORTCUT("scene_tree/toggle_exposed_node"), TOOL_TOGGLE_SCENE_EXPOSED);
+			menu->set_item_text(menu->get_item_index(TOOL_TOGGLE_SCENE_EXPOSED), node->is_exposed_in_owner() ? TTR("Unexpose Node in Instantiated Scenes") : TTR("Expose Node in Instantiated Scenes"));
 		}
 	}
 
@@ -4430,6 +4510,7 @@ SceneTreeDock::SceneTreeDock(Node *p_scene_root, EditorSelection *p_editor_selec
 	ED_SHORTCUT("scene_tree/show_in_file_system", TTR("Show in FileSystem"));
 	ED_SHORTCUT("scene_tree/toggle_unique_name", TTR("Toggle Access as Unique Name"));
 	ED_SHORTCUT("scene_tree/toggle_editable_children", TTR("Toggle Editable Children"));
+	ED_SHORTCUT("scene_tree/toggle_exposed_node", TTR("Toggle node as Exposed in scene"));
 	ED_SHORTCUT("scene_tree/delete_no_confirm", TTR("Delete (No Confirm)"), KeyModifierMask::SHIFT | Key::KEY_DELETE);
 	ED_SHORTCUT("scene_tree/delete", TTR("Delete"), Key::KEY_DELETE);
 

editor/scene_tree_dock.h

@@ -90,6 +90,7 @@ class SceneTreeDock : public VBoxContainer {
 		TOOL_SCENE_CLEAR_INHERITANCE_CONFIRM,
 		TOOL_SCENE_OPEN_INHERITED,
 		TOOL_TOGGLE_SCENE_UNIQUE_NAME,
+		TOOL_TOGGLE_SCENE_EXPOSED,
 		TOOL_CREATE_2D_SCENE,
 		TOOL_CREATE_3D_SCENE,
 		TOOL_CREATE_USER_INTERFACE,