Method and apparatus to efficiently interpolate polygon attributes in two dimensions at a prescribed clock rate
US6072505A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1998 |
| Grant date | Jun 6, 2000 |
| Priority date | — |
| Expiry date | Apr 1, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T3/403
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A rasterizer comprised of a bounding box calculator, a plane converter, a windower, and incrementers. For each polygon to be processed, a bounding box calculation is performed which determines the display screen area, in spans, that totally encloses the polygon and passes the data to the plane converter. The plane converter also receives as input attribute values for each vertex of the polygon. The plane converter computes planar coefficients for each attribute of the polygon, for each of the edges of the polygon. The plane converter unit computes the start pixel center location at a start span and a starting coefficient value at that pixel center. The computed coefficients also include the rate of change or gradient, for each polygon attribute in the x and y directions, respectively. The plane converter also computes line coefficients for each of the edges of the polygon. Line equation values are passed through to the windower where further calculations allow the windower to determine which spans are either covered or intersected by the polygon. The incrementers receive the span coverage data from the windower in addition to receiving planar coefficient values from the plane conve…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.