Read ATI's lips: no Rip-Mapping in 7500 & 8500
The Hard|OCP's NVIDIA GeForce4 Ti 4200 PREview II
was already covered in yesterday's shortbread
, but it deserves a little more attention. Though the article is really supposed to be covering NVIDIA's excellent Ti 4200, the OCP does manage to get some clarification from ATI on some recent "Rip-Mapping" rumors:
"The RADEON 8500 & 7500 products use true anisotropic filtering, not rip-mapping. They achieve the high performance they do with AF because they have the unique ability to dynamically select the number of texture samples taken for each pixel. Thus, pixels that would get no visual benefit from AF use only a single bilinear texture sample, while those that are at very sharp angles and would get the most benefit can use up to 16 bilinear samples (in 16x mode). Since 16x samples requires 16x bandwidth, and only a small fraction of the pixels on the screen ever require this many samples, the RADEON products can offer the full visual quality improvement with almost no performance hit."
That's straight from ATI's Technology Marketing Manager, folks; kudos to the OCP for getting clarification on that.