Steaming prefetching texture cache for level of detail maps in a 3D-graphics engine
US6433789B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 18, 2000 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | Feb 18, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a texture prefetching method for use in a three-dimensional graphics display system in which texture maps of an object are stored in memory for texels at (u,v) memory locations. The method of fetching texels for use in calculating (x,y) display pixel values comprises the steps of: a) identifying in (u,v) space a geometric shape to be displayed in (x,y) space, b) establishing tiles of pixels within the geometric shape for use in accessing texels, c) computing texel addresses at one side of a tile based on current addresses (topuc, topvc) and first and second derivatives of (u,v) as a function of (x) and a first derivative as a function of (y), d) computing texel addresses at an opposing side of the tile based on current addresses (u0,v0) and first and second derivatives of (u,v) as a function of (x) and a first derivative as a function of (y), and e) fetching texel blocks within the tiles as defined by the addresses in steps c) and d). In a preferred embodiment, the geometric shape is a triangle, and a tile comprises a quadrilateral having top and bottom pixel locations for two opposing sides, and step c) and step d) define comers of the quadrilateral in (u,v) space.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.