by Anton Shilov
11/20/2002 | 07:36 PM
We told you numerous times that NVIDIA’s GeForce FX graphics processor supports all the features provided by Microsoft DirectX 9.0 API and even beyond. Mostly due to their unique capabilities in vertex and pixel shaders, the Santa Clara, California-based graphics chip developer can boast with the CineFX architecture that should bring Hollywood to your personal computer. Apparently, we now doubt that NVIDIA really supports all the necessary DirectX 9.0 capabilities in hardware: according to our friends from Reactor Critical web-site, the GeForce FX also known as the NV30 graphics processor does not support Displacement Mapping.
As we know from our Matrox Parhelia Review, hardware displacement mapping support is a long-time dream of software developers who wanted to correctly display bump mapped models without making them too complex by describing each bump in a separate set of polygons. According to Microsoft, displacement mapping is based on the N-Patch approach introduced by ATI a year ago, hence, have almost nothing to do with NVIDIA’s RT-patches implemented in the GeForce3 GPU. Competing products, such as Matrox Parhelia, ATI RADEON 9700 and RADEON 9500 support the displacement mapping in hardware. Furthermore, NVIDIA does not seem to like curved surfaces very much at all: they turned off parametric surfaces support in the GeForce3 drivers due to compatibility issues a year ago, so, currently NVIDIA does not seem to support any higher order surfaces. <%BANNER[article]%>
At this point I do not know if the displacement mapping is needed to be strictly supported by hardware in order to declare “DirectX 9.0 compatibility”. If it is, NVIDIA will not be able to claim that the GeForce FX VPU is 100% DirectX 9.0 compatible.