The root object under which to search for or create the child object.
The name of the child object to find or create. Only exact matches are considered.
The scene in which to add the new scene object if it needs to be created.
The found or created child scene object.
Finds or creates a child scene object with the specified name under the given root object. It only searches the immediate children of the root object. If a child object with the specified name already exists, it is returned. Otherwise, a new scene object is created, added to the scene, and assigned the specified name.