Sketch-Based Subdivision Models

Abstract

Designing a control mesh (or a polyhedron) for a subdivision model is a tedious task. It involves many difficult decisions such as how to minimize the number of extraordinary vertices, how best to choose their valencies, and where to place them in the control mesh. In this paper, we present an intuitive and interactive approach for using sketch-based interface to design subdivision models. The input to the system is a set of strokes forming the profile curves of the surface. From the constructed control polygons of the sketched curves, a coarse and quad dominant control mesh is generated with few extraordinary vertices or faces. The corresponding limit surface interpolates the profile curves with the capability of local control across these curves and of the model in general. Although our approach is oriented towards quad-based systems such as Catmull-Clark, it could well be adopted in other subdivision schemes.