A simple way to send objects and texture sets to Unity from Maya.

  • Create your asset (modeling, texturing etc.)

  • In Maya use the aiStandardSurface shader and connect the textures
    (Use the bump2d node for Normal maps.)

  • Export the object as FBX.
    Make sure the the Embed Media option is turned on!
    An FBX can contain aiStandardSruface shaders and the basic File node connections.
    Fortunately Unity have a dedicated ArnoldStandardSurface shader type and also a special process to create the correct shader and connections when necessary. 

  • In Unity, import the FBX (drag and drop or export directly into your asset folder).

  • Select the imported asset than select the Material tab on the Inspector panel.

    • Set the Material Creation Mode to Import via MaterialDescription

    • Set the Location to Use Embedded Materials

    • Press the Extract Textures button (set the folder)

    • Press the Extract Materials button (set the folder)

    • Turn off the sRGB (Color Texture) option for all but the Albedo (base color) texture, press apply.

  • If you don’t need transparent shader, select the generated material and set the Surface Type to Opaque.
    When using the transparent surface type you might have to change a few things (Depth Test mode, Double-Sided switcher etc.).

That’s it.
Cheers, D