Menu MDL material location

ifmMDLmaterial material with MDL folders
MDL materials can be accessed on three predefined locations. By default these locations are:
All MDL materials installed by the NVIDIA MDL Material Exchange package to grant compatibilty between different packages using Iray and MDL. By default this folder is: C:\ProgramData\NVIDIA Corporation\mdl
You see this folder only if the NVIDIA MDL Material Exchange package is installed. It is strictly recommended not to delete files in this folder. It is not recommended to rename this folder or to move it to another location.
This is the place where users can place their own MDL files. By default this folder is: C:\Users\USERNAME\Documents\mdl
This is the default installation path of Iray for Maya 2.0. By default this folder is: C:\Program Files\NVIDIA Corporation\Iray for Maya 2017\materialLibraries
Click on the tree view in the Attribute Editor and open the folder to get a MDL material. Once you select the MDL material the exposed attributes appear.
Avoid having multiple MDL materials using the same name in the different folders. Each MDL material must have a unique name to prevent confusion.
For details about the displayed attributes, refer to the documentation of the loaded library. These libraries and the associated documentation are not part of Iray for Maya 2.0.
The ifmMDLmaterial replaces the ifmCustomMDL material introduced with Iray for Maya 2014. Scenes from older version will get an empty node after loading. To rebuild your scene and migrate to the new ifmMDLMaterial we provide an environment variable to use both nodes parallel. We strictly recommend to enable this function only for conversion reasons. The ifmCustomMDL node will be erased in the next version of Iray for Maya. Set the environment variable IFM_LEGACY_CUSTOMMDL=enable to get access to the old ifmCustomMDL node.
For further information about MDL, refer to the MDL Handbook provided by Nvidia.