If I have a building and the walls are one object, is it possible to make the front exterior wall have a stone texture and the back exterior wall horizontal metal siding, for example? Likewise on an interior room can there be painted walls and a wall papered accent wall if the room's walls are a single object? How are these examples achieved? So far it appears to me that if I assign a material and texture to an object the whole object is affected. How is it possible to apply a different material/texture to a surface of the object.