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:
Mar. 21, 2000
Filed:
Apr. 22, 1998
Daniel Wong, North York, CA;
Milivoje Aleksic, Richmond Hill, CA;
ATI Technologies, Inc., Thornhill, CA;
Abstract
A method and apparatus for space variant texture filtering begins when texture coordinates for a given pixel of an object being rendered are received. From the texture coordinates, first and second axis derivatives are determined. When the first and second axis derivatives have differing degrees of magnitude, a determination is made as to whether the first access derivative or the second axis derivative corresponds to a major axis. Next, a number of samples along the major axis are determined based on a logarithmic function of a ratio between the first and second derivatives. Having obtained the number of samples, a separation between the samples is determined based on derivatives along the major axis. Having obtained the number of samples and separation, one of a plurality of related texture maps (e.g., MIP maps) is referenced based on the derivatives along a minor access to obtain the samples. Having obtained the samples, they are filtered based on the number of samples to obtain a filtered texel for the given pixel.