We describe the theoretical frame for a method of creating and describing rounded objects of arbitrary topology in CAD, and its implementation for UNIGRAFIX, a polygon-based modeler developed at UC Berkeley that generates black-and-white, smooth-shaded images on several output devices. The mathematical foundation for building triangular patches interpolating cubic edges and blending with geometric continuity is given, and various approaches are discussed. To represent curvature information, we extended the UNIGRAFIX language to UniCubix, and we implemented uci, an interactive shell that interprets a UniCubix description and converts it into UNIGRAFIX wireframes or polyhedral nets that approximate curved patches. Uci also provides a prototype of a global smoothing operation, that takes a polyhedral object of arbitrary topology and creates the UniCubix representation of a smooth object interpolating the input vertices.
Title
Interpolating Patches Between Cubic Boundaries
Published
1985-12-01
Full Collection Name
Electrical Engineering & Computer Sciences Technical Reports
Other Identifiers
CSD-87-313
Type
Text
Extent
42 p
Archive
The Engineering Library
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