Patent · US Expired

Multiple depth buffers for graphics and solid modelling

US5027292A · kind A · utility

27Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 1989
Grant dateJun 25, 1991
Priority date
Expiry dateApr 19, 2009

Classification

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

Abstract

A CSG solid modelling system 10 has a triple z-buffer architecture. For each pixel stored in a pixel memory 12 there are five storage entries grouped into five buffers including a front z-buffer (F) 16 which is employed to store the depths of a front face for a currently processed z-connected product, a back z-buffer (B) 18 which is employed to store the depths of a back face for the currently processed z-connected product and a final z-buffer (Z) 20 which stores the front faces of a displayed solid. Two other buffers are an intensity buffer (T) 22 for storing the intensities associated with the front face of the current z-connected product and a final intensity buffer (I) 24 for storing the intensities of the visible faces of the displayed solid. A bus 26 couples these various buffers together and to a processor 28 which may be a central processing unit or a peripheral processor. The system provides for a solid represented by any CSG tree to be represented as a union of z-connected products and that these z-connected products be expressed as intersections of z-connected sweeps. Furthermore it is shown that expressions of z-connected products in terms of sweeps are extracted direct…

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