2008

Backface Culling
mental ray rendering correctly performs backface culling, and renders one-sided
faces much as the scanline renderer does.
3ds Max Materials in mental ray Renderings
For the most part, the mental ray renderer treats 3ds Max maps and materials
the same way the default scanline renderer does. The exceptions are listed
below. In general, if the mental ray renderer does not recognize a map or
material, it renders it as opaque black.
WARNING The mental ray renderer does not necessarily support maps or materials
provided as plug-ins from third-party vendors. It supports third-party maps and
materials only if the vendor has explicitly used the mental ray SDK to add support
for the mental ray format. Unless the third-party vendor clearly specifies mental
ray support, you should assume the map or material is unsupported, and will
render as black.
See also:
■
mental ray Renderer on page 6039
■ Getting Good Results with mental ray Rendering on page 6044
Issues for Reflections and Refractions
The maps used to create reflections or refractions, Flat Mirror, Raytrace,
Reflect/Refract, and Thin Wall Refraction, are supported by the mental ray
renderer. However, the mental ray renderer simply uses these maps as
indications to use its own ray-tracing method, leading to some restrictions on
which parameters are supported, as described in the sections “Materials” and
“Maps,” below.
Map Blurring
When reflections and refractions are ray traced, applying Blur (or Distortion,
in Flat Mirror) does not apply to reflections or refractions of environment
maps. In general, Blur and Distortion render differently than they do with
the default scanline renderer, and you might have to experiment with
parameter values to get a comparable rendering result.
6048 | Chapter 18 Rendering