Floating point texture filtering using unsigned linear interpolators and block normalizations

Abstract

Apparatus and systems utilizing fixed point filtering to perform floating point texture filtering. A texture pipe unit consisting of a texture addressing unit, texture cache unit, and texture filter unit accepts texture requests for a specified pixel from a resource and returns formatted bilinear filtered results based on the specific pixel's corresponding four texels. The texture filtering unit consists of a pre-formatter module, interpolator module, accumulator module and a format module. The pre-formatter module accepts texel data in a floating point or fixed point format. However, if the data is in a floating point format the pre-formatter module converts the floating point data into a normalized fixed point data format whereby the interpolator module may perform its bilinear interpolator functions using standardized fixed point systems and apparatus without necessitating the use of floating point arithmetic units. A method utilizing fixed point filtering to perform floating point texture filtering is also presented.