The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 1996
Filed:
Dec. 04, 1992
Kevin Martin, San Jose, CA (US);
Network Computing Devices, Inc., Mountain View, CA (US);
Abstract
A method for rendering of three dimensional images on a video subsystem which does not include clearing of the Z buffer at each frame includes establishment of a Z buffer and a sequence number in memory, where the sequence number is incremented with each successive frame rendered and the Z buffer is cleared when the sequence number reaches a predetermined value; the Z buffer is thus recycled a number of times between clears. In a more elaborate implementation, the precision of the Z buffer is adjusted to permit clearing of the Z buffer to occur either as the result of the sequence number reaching a predetermined value or as the result of the accrual of a predetermined amount of time allocated for clearing, referred to as scheduling. The scheduling method can be applied to a wide range of accounting tasks within a system. In addition, a related method for recycling the image buffer is also disclosed in which multiple colormap ID's are used to distinguish data included in a current frame from data in a prior frame, where the colormap ID's associated with the prior frames all map to the background color, leaving to be displayed only the data of the current frame.