MPI-I-2003-4-009

We discuss FaceSketch, an interface for 2D facial human-like cartoon sketching. The basic paradigm in FaceSketch is to offer a 2D interaction style and feel while employing 3D techniques to facilitate various tasks involved in drawing and redrawing faces from different views. The system works by accepting freeform strokes denoting head, eyes, nose, and other facial features, constructing an internal 3D model that conforms to the input silhouettes, and redisplaying the result in simple sketchy style from any user-specified viewing direction. In a manner similar to conventional 2D drawing process, the displayed shape may be changed by oversketching silhouettes, and hatches and strokes may be added within its boundary. Implementation-wise, we demonstrate the feasibility of using simple point primitive as a fundamental 3D modeling primitive in a sketch-based system. We discuss relatively simple but robust and efficient point-based algorithms for shape inflation, modification and display in 3D view. We discuss the feasibility of our ideas using a number of example interactions and facial sketches.