Brown Computer Graphics Group Brown Computer Graphics Group

Artistic Silhouettes: A Hybrid Approach

by J. D. Northrup and Lee Markosian.

To appear in NPAR 2000.


We present a new algorithm for rendering silhouette outlines of 3D polygonal meshes with stylized strokes. Rather than use silhouette edges of the model directly as the basis for drawing strokes, we first process the edges in image space to create long, connected paths corresponding to visible portions of silhouettes. The resulting paths have the precision of object-space edges, but avoid the unwanted zig-zagging and inconsistent visibility of raw silhouette edges. Our hybrid screen/object space approach thus allows us to apply stylizations to strokes that follow the visual silhouettes of an object. We describe details of our OpenGL-based stylized strokes that can resemble natural media, but render at interactive rates. We demonstrate our technique with the accompanying still images and animations rendered with our technique.

Accompanying quicktime movies using Radius Cinepak compression:

Art-based modeling and rendering project page