Accelerated texture lookups using texture coordinate derivatives

摘要

Methods, systems, and devices are disclosed for preparing to prefetch memory in 3D graphical shader programs. Based on the memory addresses of texels from a texture map that were previously read, a memory address of a to-be-read texel is estimated by using a first-order derivative of the memory address with respect to pixel distance. The estimated memory address is then prefetched for use when the pixel corresponding to the texel is rendered. Whether or not to perform the estimation of the texel memory address can be determined by whether the corresponding pixels are on the same, flat facet on a 3D model. Multiple directions on the facet can be used for memory address estimation as well as higher-order derivatives.

主权项

1. A method of preparing to prefetch a texel for graphics processing, the method comprising:
receiving memory addresses for texels of a texture map, the texels corresponding to a set of pixels in an image; determining that the set of pixels correspond to a common non-linear surface on different facets of a three-dimensional model; computing, using at least one processor operatively coupled with a memory, a surface derivative of a change in a texel memory location to a change in a surface location based at least in part on curve parameters of the non-linear surface; determining, based at least in part on the computed surface derivative, a predicted memory location of a texel in the texture map that corresponds to a selected pixel on the surface; and prefetching a texel for the selected pixel using the predicted memory location, wherein computing the surface derivative for prefetching is based on a determination that the pixels correspond to the same non-linear surface on different facets.