Method and system for accessing texture data in environments with high

Abstract

A system for accessing texture data in a graphics rendering system allows texture data to be stored in memories with high latency or in a compressed format. The system utilizes a texture cache to temporarily store blocks of texture data retrieved from an external memory during rendering operations. In one implementation, geometric primitives are stored in a queue long enough to absorb the latency of fetching and possibly decompressing a texture block. The geometric primitives are converted into texture block references, and these references are used to fetch texture blocks from memory. A rasterizer rasterizes each geometric primitives as the necessary texture data becomes available in the texture cache. In another implementation, geometric primitives are converted into pixels, including a pixel address, color data, and a texture request. These pixels are stored in a queue long enough to absorb the latency of a texture block fetch. The texture requests are read from the queue and used to fetch the appropriate texture blocks. As texture data becomes available in the texture cache, the texture data is sampled as necessary and combined with the pixel data read from the queue to compute output pixels.