SceneMainLoop -> SceneTree

-=-=-=-=-=-=-=-=-=-=-=-=-=-

*YOUR SOURCE MIGHT NOT WORK*
For mor information on fix:
https://github.com/okamstudio/godot/wiki/devel_scene_tree

Other stuff:
-Shower of bullets demo
-Fixes all around

scene/gui/option_button.cpp

@@ -192,7 +192,7 @@ void OptionButton::_select(int p_idx,bool p_emit) {
 	set_text( popup->get_item_text( current ) );
 	set_icon( popup->get_item_icon( current ) );
 
-	if (is_inside_scene() && p_emit)
+	if (is_inside_tree() && p_emit)
 		emit_signal("item_selected",current);
 }