Window specific control of overlay planes in a graphics display system
US5469541A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1994 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Oct 25, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/14
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and methods for selectively controlling by graphics environment window the characteristics of an overlay common to multiple-windows while operating within the context of a conventional RAMDAC overlay control architecture. Window specific overlay control is accomplished by concatenating the window, masking and overlay data as an address to a mapping memory. The bit content of the mapping memory is controlled directly by the general purpose processor to selectively refine the relationship between the concatenated input as an address and the mapping memory output as the state conveyed to the overlay control of the RAMDAC. A common overlay is thus selectively modifiable by window.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.