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:
Nov. 25, 2003
Filed:
Sep. 30, 1999
Kenneth William Egan, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus for generation of pixel lookahead information in a cached computer graphics system is provided. For each pixel-based memory operation, several data items may be generated, such as numerical values representing a coordinate point in an image coordinate space or display coordinate space and characteristic data representing a color value or depth value for the pixel. In addition, lookahead data correlated with the coordinate data is generated. The pixel operation is then issued with the characteristic data, the coordinate data, and the lookahead data. The lookahead data may contain a lookahead vector, which specifies a lookahead vector direction and a lookahead vector length, and a lookahead valid flag, which indicates whether associated lookahead data is valid for the pixel operation. The lookahead direction may be computed based on the coordinate data of the pixel operation and coordinate data for a pixel operation to be performed within a threshold number of pixels operations from the pixel operation. By providing lookahead information based on the rendering state of the graphics subsystem, pixel operation intentions may be indicated prior to the issuance of a pixel operation so that the pixel data may be prefetched into a cache.