Patent · US Expired

System and method for clearing depth and color buffers in a real-time graphics rendering system

US6982713B2 · kind B2 · utility

4Cited by
3References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 13, 2003
Grant dateJan 3, 2006
Priority date
Expiry dateDec 5, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T15/405
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and system for clearing depth and color buffers in a real time graphics rendering system 10. The method and system are able to improve both depth and color buffer clearing. The method and system may utilize a frame flag, a depth clearing module, and a fast color and frame flag clearing module. The system assigns a frame flag to each pixel, which is used to determine whether the current Z value for the pixel is valid. The frame flag may be attached to Z value in the depth buffer. Instead of filling entire depth and color buffers with background values, the system only fills the holes that were not drawn in the previous frame. The fast color and frame flag clearing module traverses a rectangular area, tile by tile, where a tile is a block of pixels, to determine whether each pixel is background by checking the frame flags that are read from the depth buffer. If at least one pixel of a tile is background, the module updates those pixels' color with background color by sending requests to memory interface.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.