Over-sketching Operation to Realize Geometrical and Topological Editing across Multiple Objects in Sketch-based CAD Interface

We developed a new general-purpose sketch-based interface for use in two-dimensional computer-aided design (CAD) systems. In this interface, a sketch-based editing operation is used to modify the geometry and topology of multiple geometric objects via over-sketching. The interface was developed by inheriting a fuzzy logic-based strategy of the existing sketch-based interface SKIT (SKetch Input Tracer). Using this interface, a user can make drawings in a creative manner; e.g., they can start with a rough sketch and progressively achieve a detailed design while repeating the over-sketches.