A Versatile Interactive 3D Brush Model

An original painting created by Eriko Baxter with our new virtual brush model.

William Baxter
Ming Lin

We present a flexible modeling approach capable of realistically simulating many varieties of brushes commonly used in painting. Our geometric model of brush heads is a combination of subdivision surfaces and hundreds of individual bristles represented by thin polygonal strips. We exploit bristle-to-bristle coherence, simulating only a fraction of the bristles and using interpolation for the remainder. Our dynamic model incorporates realistic physically-based deformation, including anisotropic friction, brush plasticity, and tip spreading. We use an energy minimization framework with a novel geometric representation of the brush head to generate a wider variety of brushes. Finally, we have developed an improved haptic model that provides realistic force feedback, directly related to the results of the brush dynamic simulation.

Using this model, we are able to simulate a wide range of brush styles and create an excellent variety of strokes such as the crisp, curvy strokes ofWestern decorative painting, or rough scratchy strokes like certain Oriental calligraphy. We have also developed an exporter for a popular free 3D modeling package that makes it easier for non-programmers to create any desired style of brush, real or fanciful.

William Baxter and Ming Lin,
A Versatile Interactive 3D Brush Model,
To appear in Proc. of Pacific Graphics 2004,
October, 2004.
(Paper pre-print, ~9MB)

Video (~29 MB, AVI/MS MPEG4 Codec)

Each of these images was created using our new brush models with the previously published paint model of the dAb system. Many thanks to our artists.

(top) Strokes from the new brush model.
(bottom) Strokes from the previous brush model.

(left) Strokes from the new brush model.
(right) Strokes from the previous brush model.

Brush models and example strokes created with each.
Links and Related Work:
dAb: Interactive Haptic Painting with 3D Virtual Brushes
A Viscous Paint Model for Interactive Applications
IMPaSTo - A Realistic, Interactive Model for Paint