Home Technical Talk

3ds Max Material ID to Smoothing Groups

I create some models in MoI 3D and want to retopologize them in 3ds Max using QuadRemesher. For QR to work properly I need to set up smoothing groups. Luckily MoI 3D exports all parts which need to have a unique smoothing group in separate elements. SO I quickly give them some random materials using material IDs to have some visual feedback on the parts that need to have a smoothing group.

Is there a quick way to turn those material IDs to smoothing groups?


  • Kanni3d
    Offline / Send Message
    Kanni3d ngon master
    You could select by ID in the same little window that you can assign material id's to polygons, and then give it an autosmooth (which can be hotkeyed) of a low threshold, like 180, so that the entire selection of material id gets one unique smoothing group next to another.
  • second_ich
    Thanks, that makes it a bit faster. Still would be nice to automate it completly. I just need to turn Material ID 1 to smoothing group 1, material ID 2 to smoothing group 2, M ID 3 to SG 3...
  • poopipe
    Offline / Send Message
    poopipe grand marshal polycounter
    It's pretty trivial to script that sort of thing in max. if you poke around the docs for half an hour you should be able to  put something together
  • coven
    Offline / Send Message
    coven polycounter lvl 6
    You can do it with the Data Channel Modifier. 
    1. Add Data channel Modifier on top
    2. Add Face Input - Material ID
    3. Add Normalize modifier - more on this later
    4. Add Face Output and set to Smoothing Groups
    Now go to Normalize modifier and set min to 1 and max to how ever many material ID's you have. You have to do this because the Material ID's internally start at 0. Would be good to have a simple math process operator here instead.
  • coven
    Offline / Send Message
    coven polycounter lvl 6
    Well scratch that. The transfer isn't 1 - 1. Smoothing groups are bitwise values (1 - 2 - 4 - 8 - 16 etc.). Maxscript is the most logical choice, and this points to a unexpected result in DCM. I'll log that ;)
Sign In or Register to comment.