Expressive brush strokes

Abstract Expressive brush strokes are modeled using a technique based on variable offset approximation of uniform cubic B -splines. The trajectory of a brush stroke is represented as a 3D cubic B -spline and each bristle as a 3D offset cubic B -spline of this trajectory. The first two coordinates are the spatial position coordinates and the third coordinate represents the shade of each bristle. This technique facilitates the process of inputting data, simplifies the computation task, and provides some advantages in the animation process of brush strokes.