MARKET: Mental Ray ships as the standard renderer with Softimage|XSI, is included with Maya and 3D Studio Max, and is available as a renderer for use with other animation systems.
KEY FEATURES: Mental Ray is a sophisticated programmable raytracer that also supports global illumination, for radiosity-style bounced lighting and caustic effects. Mental Ray shaders are regular program code, typically compiled from C++, which has speed advantages over more sophisticated scripting languages to develop shaders, but also can make shader development more difficult. Every aspect of the rendering process in Mental Ray is controlled by programmable plug-in shaders, with geometry shaders customizing the tessellation or subdivision of objects, material and texture shaders controlling every aspect of the surfaces, photon shaders controlling global illumination effects, camera shaders simulating different lens types and antialiasing, output shaders controlling post-processed effects, and other categories.
Mental Ray is also available as an optional renderer to use with 3D Studio Max (although that provides a limited version without programmable shaders.)