Processing graphic objects for fast rasterised rendering
US6483519B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1999 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Sep 10, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/42
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed are methods, apparatus (1) and computer readable media for rendering at least one graphic object (80, 90) described by at least one edge (82-86, 92-98) into a raster pixel image (78) having a plurality of scan lines and a plurality of pixel locations on each scan line. For each scan line, coordinates of intersection of those edges of the objects that intersect the scan line are determined in a predetermined order. This is preferably achieved by processing edge records (418) using a number of buffers (402, 404,406, 412,420, 422) thereby enabling efficient sorting of edge intersections into order. For each adjacent pair of edge intersections, information (530) associated with the corresponding object is examined to determining a set of active objects (508, 510) for a span of pixel locations between the corresponding pair of edge intersections. For each span of pixel locations, the corresponding set of active objects is used to determine (600) a value for each of the locations within the span. The information may include one or more of a fill count, a clip count and other factors. A compositing model accommodating opacity is also disclosed, as are stack operations used to fa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.