And the answer is:
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You can still unlock the “UV Generator” shader in mental ray.
You’ll have to edit the “3dsmaxshaders.mi” file located @ C:\Program Files\Autodesk\3ds Max 2014\NVIDIA\shaders_standard\mentalray\include
Before you edit the file, make a backup in case you make a mistake.
With the file opened in Notepad search (Ctrl + F) for “UV” until you find the following text.
gui “gui_max_base_UVGenerator” { control “Global” “Global” ( “uiName” “UV Generator”, “helpCHM” “max/max help.chm”, “category” “Texture Space Mapping”, “hidden”
Now just change the “hidden” to #”hidden” (just add the pound sign in front) and save the file.
Restart 3ds Max and in your mental ray shaders you’ll now see the “UV Generator” appear.
To get this pass with your image make a separate a new Render Element called “mr Shader Element”.
In this element you can add the “UV Generator” map to create a pass with your UV’s.
Turn off filtering and “Apply Shadows” to get the correct result.
Also make sure you have your frame buffer set to 32-bit in the mental ray Renderer settings to get the full range in the Render Elements.
Since Max 2014 though, your render elements might not be outputting unfiltered data correctly when using Unified Sampling, so you’d be best off rendering a separate pass from a separate file.
Hope that helped,
M.
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