Colloquy Cycle on Thursday, January 15, 1998 - 16:15

Due to the surface meshes produced at increasing complexity in many applications, interest in efficient simplification algorithms and multiresolution representation is very high. An enhanced simplification approach together with a general multiresolution data scheme will be presented in the seminar.

JADE, a new simplification solution based on the Mesh Decimation approach has been designed to provide both increased approximation precision, based on global error management, and multiresolution output. Results will be presented on Jade's empirical time complexity, approximation quality, and simplification power (together with a comparison with other simplification solutions).

Moreover, on the basis of these simplification techniques, we foresee a modeling framework based on three separate stages (shape modeling, multiresolution encoding and resolution modeling), and propose a new approach to the last stage, resolution modeling, which is highly general, user-driven and not strictly tied to a particular simplification method. The approach proposed is based on a multiresolution representation scheme for triangulated, 2-manifold meshes, the Hypertriangulation Model (HyT). This scheme allows to selectively "walk" along the multiresolution surface, moving between adjacent faces efficiently. A prototypal resolution modeling system, Zeta, has been implemented to allow interactive modeling of surface details. It supports: efficient extraction of fixed resolution representations; unified management of selective refinement and selective simplification; easy composition of the selective refinement/simplification actions, with no cracks in the variable resolution mesh produced; multiresolution editing; interactive response times.