Patent ID: 6181347
Filing Date: 2001-01-30
Classification: G06T

Abstract:
A computer system that applies texel values from a texture map to computer screen pixels by selectively using a variety of texture mapping techniques, said computer system comprising:a texture map address generator that converts an x, y pixel address to a fractional coordinate in a texture map including an integer portion and a fractional portion, said fractional coordinate corresponding to one of a plurality of regions in said texture map, said regions include a first plurality of regions in which point sampling is performed, a second plurality of regions in which two-texel averaging is performed, and another region in which four texel averaging is performed;a selectable mode smoothing filter address selection unit coupled to said texture map address generator, said selectable mode smoothing filter address selection unit using said fractional coordinate to generate an integer coordinate in said texture map of a texel to be used in applying said texel values to said pixels, said selectable mode smoothing filter address selection unit further determining to which region said integer coordinate corresponds to determine an appropriate filtering technique to use to render a pixel, and further said selectable mode smoothing filter address selection unit calculating scale factors for two and four texel averaging in which said scale factor include the range of 0 to 1, including 0 and 1;wherein said scale factors are calculated by subtracting a first value equal to 1/4 from said fractional coordinate and multiplying the difference by a second value equal to 2;a texture memory device that stores said texture map; andan address translator disposed between said selectable mode smoothing filter address selection unit and said texture memory that translates said integer texture map coordinate to a texture memory address.