NURBS in VRML

ABSTRACT

In the days of VRML 1.0, NURBS seemed to be too complex to be adapted to the specification. Current development of hardware compels us to reevaluate this idea: While CPU clocks break the 1-GHz barrier, users still have to cope with 56K modems. NURBS meet exactly these demands. A NURBS description is a compact storage form, but its evaluation requires more computational effort. In addition, NURBS can be utilized for morphing effects and they provide a means for a smooth LOD. Adopting trimmed NURBS allows visualization of complex CAD models in VRML. This paper gives an overview of the proposed nodes and their implementation and applications. We take a closer look at LOD, animations and trimmed NURBS. Finally, we look ahead and briefly touch on an emerging new representation, subdivision surfaces.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS

Additional Classification:
  I. Computing Methodologies
  I.6 SIMULATION AND MODELING

General Terms:
Design, Experimentation

Keywords:
NURBS, parametric surfaces, subdivision surfaces, trimmed NURBS