This page provides information on the MDL Material.

 

Overview

The VRayMDLMtl material loads NVIDIA Material Definition Language files (.mdl) and renders them directly with V-Ray.

V-Ray supports NVIDIA Material Definition Language, version 1.5.2.

The MDL Material does not work within Distributed Rendering at this time.

 

 

||Right-click on the geometry|| > Assign New Material... > VRay section > VRay Mtl MDL


 

||V-Ray Shelf|| > Right-click to Create V-Ray Materials button > VRay Mtl MDL

 


||Hypershade|| > Window tab > Create... > VRay section > VRay Mtl MDL



 

 

Installed Material Library

The following MDL material files are included when installing V-Ray for Maya. They are located in Local Disk (C:) > Program Files > Chaos Group > V-Ray > Maya 20yy for x64 > mdl.


 

 
Aluminum Anodized

 


Architectural

 


Asphalt

 

 

 


Carbon composite

 


Carpet Berber White

 


Ceramic Tiles Small

 

 

 

 
Chrome

 

 
Coated Flipflop Paint

 

 
Coated Flint Glass

 

 

 

 
Colored Wax

 

 
Concrete

 

 
Concrete Polished

 

 

 

 
Copper

 

 
Granite Black

 

 
Mahogany Floorboards

 

 

 

 
Marble White

 

 
Metal Examples

 

 
Noise Flow Glossy

 

 

 

 
Noise Perlin Glossy

 

 
Noise Worley Glossy

 

 
Pattern Blended

 

 

 

 
Pattern Checker Glossy

 

 
Porcelain

 

 
Resin Polyurethane Matte

 

 

 

 
Rubber Studded Black

 

 
Stucco

 

 
Walnut Semi-Gloss

 

 

 

 

Basic

 

The Basic rollout provides the attributes used to set the path to the .mdl file that you wish to load into your chosen material, and an Update button needed to refresh the other attributes available, based on the material file used.


MDL file – Specifies the file path and .mdl file loaded.

Chosen material – If more than one material definition is included in the loaded .mdl file, the selected materials will be seen in the rollouts below.

MDL parameters– The Update button refreshes the additional material-specific attributes for the loaded .mdl file.

 

 

Parameters

Any additional material-specific attributes (if any) are listed in this rollout. The example below shows parameters for the Coated Flip-flop Paint material.

 

 MDL material attributes that can accept Render Nodes to map color values can now use File textures as input. Note that while other texture types may also be used, only File textures are guaranteed to work properly.

 

Asphalt parameters

Advanced

Max Ray Depth – Specifies the maximum reflection/refraction depth for the shader.

Remap Roughness – When enabled (default), determines whether the plugin expects squared values for GGX Roughness settings.

 

System Attributes

Filename – Specifies the file path and .mdl file loaded.

 

 

Importing NVIDIA vMaterials

In order for the MDL Material to correctly import NVIDIA vMaterials, the following two paths should be set in the environment variable shown below:

VRAY_MDL_PATH_MAYA20yy_x64=%PROGRAMFILES%\Chaos Group\V-Ray\Maya 20yy for x64\mdl;%PROGRAMDATA%\NVIDIA Corporation\mdl;%USERPROFILE%\Documents\mdl

where yy is the version of Maya installed.

 

Example:

VRAY_MDL_PATH_MAYA2018_x64=C:\Program Files\Chaos Group\V-Ray\Maya 2018 for x64\mdl;%PROGRAMDATA%\NVIDIA Corporation\mdl;%USERPROFILE%\Documents\mdl

 

Importing MDL Files from Substance Designer 

In some cases, when using MDL files exported from Substance Designer, V-Ray may fail to load some modules. In order to load these modules, a folder needs to be set up before starting Maya, as expalined below:

1.  Make a folder, for example, X:\MDL, that will act as the MDL repository. Put the MDL modules that are exported from Substance Designer into this folder.

2.  Put the textures needed by the MDL materials in the same repository in their respective subfolder (for example, X:\MDL\MDL_Plywood_02).

3.  Tell V-Ray where the MDL repository is by appending it to the VRAY_MDL_PATH_MAYA20yy_x64 environment variable.

4.  Find the folder where Substance Designer keeps its MDL modules (usually C:\Program Files\Adobe\Adobe Substance 3D Designer\resources\view3d\iray\alg but may differ from version to version) and append its path to the same environment variable. 

In the end, the environment variable should look something like:

VRAY_MDL_PATH_MAYA2018_x64=C:\Program Files\Chaos Group\V-Ray\Maya 2018 for x64\mdl;C:\Program Files\Adobe\Adobe Substance 3D Designer\resources\view3d\iray\alg;X:\MDL

 

Known Limitations

 

  • material_emission.mode is ignored
  • material.backface is ignored

  • df::diffuse_transmission_bsdf is not supported

  • df::backscattering_glossy_reflection_bsdf is not supported

  • df::measured_bsdf is not supported

  • From the “alternative distribution functions”, only df::microfacet_ggx_smith_bsdf is implemented

  • df::measured_edf and df::spot_edf are not supported

  • df::anisotropic_vdf is not supported

  • 3D textures are not yet supported

References