Oriental Brush Simulation using 3 Dimensional Action.

Calligraphy is an art of beautiful handwriting seen widely in Oriental countries. The principle tool for oriental calligraphers is the oriental brush which has characteristics different from a pen. The purpose of this paper is to realize a simulation of the expressive oriental brush with a pen tablet and a web camera. Especially we have focused on the effects of the pressure that the calligrapher gives to the oriental brush. The information from the tablet such as the xy-coordinates, pressure, altitude, and azimuth of the pen can be utilized to simulate the oriental brush. However the pen pressure values obtained from the pen tablet are not suitable for an elaborate simulation of the oriental brush in that the calligrapher cannot closely control the pressure. In our system, the calligrapher uses a device brush, i.e., a device pen with attached hairs, as a substitute for the oriental brush. The system measures the z-coordinate of the brush, i.e., the height from the surface of the tablet to the center of gravity of the brush bristles, by using a web camera and utilizes it as a parameter for the brush pressure. The aerial movements of the brush are reflected to the various aspects such as the shape and size of the droplet, ink consumption, ink diffusion, and ink scratchiness, which enables users to write calligraphy with the device brush with a feeling that they use a real oriental brush and to make more delicate expressions.