Introducing design intent in discrete surface modelling

In the early design phases, stylists need high-level tools to properly support their creativity. In a sketch, the character of an object is usually impressed through certain curves, semantically important from the aesthetic point of view. Therefore, modelling with a curve-oriented methodology seems to re¯ect designers' habits during the sketching phase. Capturing such semantics of curves is the intention of the proposed modelling approach. The concept of styling features is here described and applied to a discrete surface representation, preferred to the standard splines in order to answer still exiting drawbacks of continuous representations along the entire development process. In this paper, features obtainable by means of generalised sweep operations are de®ned and treated on subdivision surfaces. The choice of this type of feature is due to the expressive power in describing recurring shapes in industrial products.