Method and apparatus for virtualizing off-screen memory of a graphics engine
US5757386A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 11, 1995 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Aug 11, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/36
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An application request for off-screen VRAM is satisfied transparently to the application by allocating off-screen VRAM, if available, or system RAM if off-screen VRAM is unavailable. In addition, a list is kept of previous memory requests so that requests which were satisfied by allocating system RAM can be switched to off-screen VRAM, if such off-screen VRAM should later become available. Allocation of off-screen VRAM is controlled by a device driver that responds to various application memory requests and controls the off-screen VRAM resources, among other things. The device driver receives an allocation request for off-screen VRAM and determines whether the request may be honored with available off-screen VRAM resources. If the request can be honored with available off-screen VRAM resources, the device driver allocates a portion of the available off-screen VRAM resources to honor the request and decreases the amount of available off-screen VRAM resources. If the request cannot be honored with available off-screen resources, the device driver allocates a portion of system RAM to honor the request. The device driver also receives and processes requests to deallocate, previously al…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.