Removing Polar Rendering Artifacts in Subdivision Surfaces

Abstract

A polar artifact occurs in subdivision surfaces around high valency vertices. It manifests as large polygons in an otherwise finely subdivided mesh. It is particularly noticeable in subdivision schemes that have been tuned to improve the appearance and behaviors of the limit surface. Using the bounded curvature Catmull-Clark scheme as an example, we describe three practical methods by which this rendering artifact can be removed, thereby allowing us to benefit from the improved character of such tuned schemes.