The 3dsmax UI only allows you to set material effects ID up to 16 channels. The VRayMtl allows you to go beyond this using the effects ID override but other types of materials don’t have any UI to adjust this. This tool using a backdoor into 3dsmax to set the effects ID beyond the 16 limit imposed by the UI.
This means you can create masks for every material in your scene. Using this tool you can either assign effects IDs by hand or just press to automatically create them and their mask render elements.
You can also make a Vray Multi-matte mask for each layer in the scene too, this uses the include/exclude lists rather than the GBuffferIds, so that you can therefore use the GBuffer IDs for doing variation with texture maps or mask objects individually if you want to.
Get it on ScriptSpot!
http://www.scriptspot.com/3ds-max/scripts/power-masker
Max Made Easy, a blog by Dave Wortley 
Hello Dave,
I’ve tried your script and it’s superb useful, there is one 1 minor thing might i suggest that the naming convention of the MMEs in the script right now i find it does not work verywell with animations and separate passes (i prefer to work with separate passes than muti channel EXR), right now the name is “MME_1+(frame number),” so i modifed it a little bit by adding a “_” to separate the MME’s number from the frame number, it looks like this:
theElement.elementName = (“MME_” + ((ceil (1.0 * i / 3)) as integer) as string + “_”)
after that all the MMEs are named like “MME_1_0001.exr”, it’s better for my compositing program.
I’m not sure if my method is a smart one because i’m very new to maxscript, but i still wanted to let you know if you find it useful. Thanks for the script!
Anh Vu.
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Good spot, fixed on script spot now thank you!
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