From 8aea5136f8923f1437cd44c048ddf78ac08152da Mon Sep 17 00:00:00 2001
From: vaner-org <angadmishra@outlook.com>
Date: Thu, 29 May 2025 03:57:17 +0530
Subject: [PATCH] Adds "Set as Main Scene" option to EditorSceneTabs context
 menu

Adds the option to quickly set main scene by right-clicking a scene tab. If the scene has no root, then the option is greyed out. If the scene is unsaved, the file is saved and then set as main scene.

Co-Authored-By: Alex Tam <65537185+altamkp@users.noreply.github.com>
---
 editor/editor_node.cpp             | 18 ++++++++++++++++++
 editor/editor_node.h               |  2 ++
 editor/scene/editor_scene_tabs.cpp |  8 +++++++-
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/editor/editor_node.cpp b/editor/editor_node.cpp
index ce1c82faf70..301244c82a3 100644
--- a/editor/editor_node.cpp
+++ b/editor/editor_node.cpp
@@ -2600,6 +2600,11 @@ void EditorNode::_dialog_action(String p_file) {
 			}
 		} break;
 
+		case SAVE_AND_SET_MAIN_SCENE: {
+			_save_scene(p_file);
+			_menu_option_confirm(SCENE_SET_MAIN_SCENE, true);
+		} break;
+
 		case FILE_EXPORT_MESH_LIBRARY: {
 			const Dictionary &fd_options = file_export_lib->get_selected_options();
 			bool merge_with_existing_library = fd_options.get(TTR("Merge With Existing"), true);
@@ -3332,6 +3337,19 @@ void EditorNode::_menu_option_confirm(int p_option, bool p_confirmed) {
 
 		} break;
 
+		case SCENE_SET_MAIN_SCENE: {
+			const String scene_path = editor_data.get_scene_path(editor_data.get_edited_scene());
+			if (scene_path.is_empty()) {
+				current_menu_option = SAVE_AND_SET_MAIN_SCENE;
+				_menu_option_confirm(SCENE_SAVE_AS_SCENE, true);
+				file->set_title(TTR("Save new main scene..."));
+			} else {
+				ProjectSettings::get_singleton()->set("application/run/main_scene", ResourceUID::path_to_uid(scene_path));
+				ProjectSettings::get_singleton()->save();
+				FileSystemDock::get_singleton()->update_all();
+			}
+		} break;
+
 		case SCENE_SAVE_ALL_SCENES: {
 			_save_all_scenes();
 		} break;
diff --git a/editor/editor_node.h b/editor/editor_node.h
index 35b0a18c672..7c2f0131014 100644
--- a/editor/editor_node.h
+++ b/editor/editor_node.h
@@ -148,6 +148,7 @@ public:
 		SCENE_SAVE_SCENE,
 		SCENE_SAVE_AS_SCENE,
 		SCENE_SAVE_ALL_SCENES,
+		SCENE_SET_MAIN_SCENE,
 		SCENE_MULTI_SAVE_AS_SCENE,
 		SCENE_QUICK_OPEN,
 		SCENE_QUICK_OPEN_SCENE,
@@ -216,6 +217,7 @@ public:
 		SCENE_TAB_CLOSE,
 		SAVE_AND_RUN,
 		SAVE_AND_RUN_MAIN_SCENE,
+		SAVE_AND_SET_MAIN_SCENE,
 		RESOURCE_SAVE,
 		RESOURCE_SAVE_AS,
 		SETTINGS_PICK_MAIN_SCENE,
diff --git a/editor/scene/editor_scene_tabs.cpp b/editor/scene/editor_scene_tabs.cpp
index cb5f88a5352..ced86f6b5e0 100644
--- a/editor/scene/editor_scene_tabs.cpp
+++ b/editor/scene/editor_scene_tabs.cpp
@@ -30,6 +30,7 @@
 
 #include "editor_scene_tabs.h"
 
+#include "core/config/project_settings.h"
 #include "editor/docks/inspector_dock.h"
 #include "editor/editor_main_screen.h"
 #include "editor/editor_node.h"
@@ -192,11 +193,16 @@ void EditorSceneTabs::_update_context_menu() {
 	DISABLE_LAST_OPTION_IF(!can_save_all_scenes);
 
 	if (tab_id >= 0) {
+		const String scene_path = EditorNode::get_editor_data().get_scene_path(tab_id);
+		const String main_scene_path = GLOBAL_GET("application/run/main_scene");
+
 		scene_tabs_context_menu->add_separator();
 		scene_tabs_context_menu->add_item(TTR("Show in FileSystem"), SCENE_SHOW_IN_FILESYSTEM);
-		DISABLE_LAST_OPTION_IF(!ResourceLoader::exists(EditorNode::get_editor_data().get_scene_path(tab_id)));
+		DISABLE_LAST_OPTION_IF(!ResourceLoader::exists(scene_path));
 		scene_tabs_context_menu->add_item(TTR("Play This Scene"), SCENE_RUN);
 		DISABLE_LAST_OPTION_IF(no_root_node);
+		scene_tabs_context_menu->add_item(TTR("Set as Main Scene"), EditorNode::SCENE_SET_MAIN_SCENE);
+		DISABLE_LAST_OPTION_IF(no_root_node || (!main_scene_path.is_empty() && ResourceUID::ensure_path(main_scene_path) == scene_path));
 
 		scene_tabs_context_menu->add_separator();
 		scene_tabs_context_menu->add_shortcut(ED_GET_SHORTCUT("editor/close_scene"), EditorNode::SCENE_CLOSE);