In this paper, we describe a solid modeling representation that incorporates metaballs and skeletons to create a hybrid representation called “skeleballs”. Skeleballs support the kind of robust editing and range of shape deformation needed for automated shape generation. Metaballs are an implicit representation based on blended spherical objects; they provide flexibility and smooth localized deformations. Skeletons are reduced-dimensional shape descriptors that capture essential geometric and topological characteristics and enable construction of a well-behaved implicit solid representation. Robust deformation is attained by superposing metaball functions on a skeleton-based implicit representation. Automated local parametrization of the design space is obtained by simply placing metaballs at points distributed across the surface and employing their amplitudes as search parameters. The hybrid skeletal/metaball representation ensures solid validity under general deformation operations, readily supports topological changes, provides for the generation of shape parametrizations, and supports multi-resolution editing. The effectiveness of the hybrid representation is demonstrated in the context of an automated shape generation example.

This content is only available via PDF.
You do not currently have access to this content.