Patent · US Expired

Method and apparatus for resolving pixel data in a graphics rendering system

US5949428A · kind A · utility

152Cited by
25References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 27, 1996
Grant dateSep 7, 1999
Priority date
Expiry dateJun 27, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T15/60
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In a graphics rendering system, an apparatus for resolving depth sorted lists of pixel fragments includes color and alpha accumulators for computing color and alpha values from the pixel fragments in a fragment list. Pixel fragments include color, alpha, coverage data. The coverage data describes how a geometric primitive covers sub-pixel regions of a pixel using a coverage mask. Pixel circuitry according to a clock-optimized approach includes separate color and alpha accumulators for computing color and alpha values for sub-pixel regions of a pixel. The accumulated color values are then summed and scaled to compute final color values for a pixel. To reduce hardware requirements, pixel circuitry in a hardware-optimized approach recognizes that some pixel regions have common accumulated alpha values as each fragment layer is processed. As such, color contributions for fragment layers can be computed using a single color accumulation operation for a pixel region having common alpha values.

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