From iray dev blog, Nvidia has introduced the iray Material plugin for 3ds Max (2013) >> Light Path Expressions in iray >> GLK...
>> Light Path Expressions in iray
>> GLK-Class SUV renderings by Jeff Patton
Features:*3 layers: Glossy Coating, Metallic Flakes, Glossy/Diffuse/Transparent Base
*Backscattering (for realistic fabrics)
*Metallic flakes (for great car paint)
*Thin film coating
*Anisotropy on each layer
*Displacement, bump, round corners, cutout
also Artur Leao has unveiled his 3dsmax plugin iray Manager 2013. This version of iray Manager added iray Material 1.2 and enables support for the iray string options in 3ds Max.
Download iray Material plugin for 3ds Max here
Download Iray Manager here
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