Graphics system
US6697066B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 2001 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | May 15, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/80
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Shading values in a graphics processing system are determined by using approximation techniques. For example, where a Beckmann Distribution Function (BDF) is used, the shading values are determined by reformulating the BDF in terms of the scalar product of the surface normal and the viewpoint-light half-vector to produce a modified BDF. A portion of the BDF is divided into a plurality of intervals, each defined by first and second control points at its boundaries. Each interval is then approximated using a cubic approximation to produce coefficients for use in determining the shading values. In alternative embodiments, other functions are approximated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.