Anti-aliasing line pixel coverage calculation using programmable shader
US7164430B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 2003 |
| Grant date | Jan 16, 2007 |
| Priority date | — |
| Expiry date | May 20, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T11/203
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and method for rendering a non-zero thickness line on a pixel-limited output device such that aliasing of the line is reduced. The edges defining a line segment are expanded to insure that any pixel touched by the line segment has its center included in the bounds of the line segment. The area of any pixel partially or fully covered by the expanded line is determined. If one edge of the line traverses the pixel, the area is determined according to whether a triangular or triangular plus parallelogram area is covered. If more than one edge of the line segment traverses a pixel, the area covered is computed based on the single edge case. With the area covered by the line segment known, the color or shading of the pixel is determined by linear interpolation between the line and the background.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.