System and method for generating smooth low degree polynomial spline surfaces over irregular meshes
US5602979A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 15, 1995 |
| Grant date | Feb 11, 1997 |
| Priority date | — |
| Expiry date | Dec 15, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T17/20
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and method for modeling smooth free-form shapes using B-splines over irregular meshes, in a simple and efficient manner, to generate a display of aesthetically pleasing shapes is disclosed. A low degree parametric polynomial representation is generated. As a result, techniques for surface-surface or ray-surface intersection are faster and more robust than possible with existing techniques. In accordance with the present invention, an input mesh M.sup.0 is initially simplified by isolating irregularities and constraining geometry. First, the input mesh M.sup.0 is subjected to general refinement, whereby a new mesh M.sup.1 is constructed, which in turn is subjected to constrained refinement, whereby another new mesh M.sup.2 is constructed. After the general and constrained refinement steps, the mesh M.sup.2 is broken up into a set of "quad-nets" corresponding to each of its vertices. Finally, these quad nets are used as local geometry, over which, 4 cubic Bezier triangles are constructed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.