If the destination id is 0 the objects will be unlinked from the source collection.
Moves the objects with object ids as specified in the second parameter from the collection with id source id to the collection with the id destination id. If the destination id is 0 the objects will be unlinked from the source collection. If this is the last instance of that object it will be deleted. If you want to delete all instances at once, use hw_deleteobject().