3D graphics rendering system for performing Z value clamping in near-Z range to maximize scene resolution of visually important Z components
US6618048B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 2000 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Jun 23, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/405
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A graphics system including a custom graphics and audio processor produces exciting 2D and 3D graphics and surround sound. The system includes a graphics and audio processor including a 3D graphics pipeline and an audio digital signal processor. The graphics pipeline performs Z-buffering and optionally provides memory efficient full scene anti-aliasing (FSAA). When the anti-aliasing rendering mode is selected, Z value bit compression is performed to more efficiently make use of the available Z buffer memory. A Z-clamping arrangement is used to improve the precision of visually important Z components by clamping Z values to zero of pixels that fall within a predetermined Z-axis range near the Z=0 eye/camera (viewport) plane. This allows a Z-clipping plane to be used very close to the eye/camera plane—to avoid undesirable visual artifacts produced when objects rendered near to the eye/camera plane are clipped—while preserving Z value precision for the remaining depth of the scene. In an example implementation, a Z value compression circuit provided in the graphics pipeline is enhanced to effectuate Z-clamping within the predetermined range of Z values. The enhanced circui…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.