Traditional Chinese calligraphy and painting rely heavily on the artist's skill in executing brushstrokes. While CAD systems have been able to help the user in a variety of graphics design activities ranging from architectural and engineering drawings to very realistic 3D renderings, the infinite variations of the brushstroke still present a challenging modelling problem. The author shows some possibilities in modelling brushstrokes using Bezier techniques. Cubic B6zier functions are used to model the following attributes of brushstrokes: variation of shape or outline of a brushstroke; shade or colour variation along and across the brushstroke; some effects due to the variation of moisture content of the brush as well as paper characteristics. Idealized brushstrokes can be produced by supplying a few parameters (primarily, B6zier control points). A program processes these parameters and outputs a PostScript* program which is then executed by a PostScript equipped printer.
computer-aided design, brushstrokes, B~zier curves
CAD systems make it possible for many users to create graphics designs in a reasonable amount of time. Without CAD systems, some designs could either be very time consuming and expensive to produce using traditional methods or simply impossible. CAD systems provide powerful tools to help users create designs ranging from simple line and curve drawings to very complex architectural and engineering drawings and even very realistic 3D renderings. Users who have trouble using a compass to draw a circle can produce a perfect drawing of a circle by pressing a few keys. Those who never progressed beyond crayons can produce beautiful 3D renderings of machine parts or fictional scenery with the help of CAD systems.
Traditional Chinese painting and calligraphy share the same minimal set of material, namely, paper, brush, ink stick and ink stone. Liquid ink is produced by placing some water on the ink stone and rubbing the ink stick against the water puddle on the ink stone. The jet black ink diluted with water can produce an infinite number of shades of grey. In the hands of trained artists, bamboo leaves, pine needles, and lotus flowers come alive with skilful brushwork. Many factors influence the.