"Unfold 3d Process Error" - Use the legacy unwrapping algorithm.

[Anonymous]

Hello, 

When I want to unfold my UVs I get this error "Unfold 3d Process Error". I saw that Autodesk acknowledged this as an issue due to limitation with AMD CPUs (I have a Ryzen 3800X). They propose to disable the processor's SMT in the Bios, which I did, but it didn't work.  
Now, I want to use the legacy unwrapping algorithm, as they propose it as well. However I don't know how to enable it. I believe it is something you select in the Unfold settings, but I don't have any way to do so. 

So how do you enable it, and do you know if there is any thing to help with this amd problem  ? 
Thank you 🙂 

[t_chanma]

You can Shift + click the Unfold button in the UV Editor to open the options.  There's a Legacy option in there.

https://help.autodesk.com/view/MAYAUL/2020/ENU/?guid=GUID-039FFDA5-3AC5-4CCF-A53E-546CCA6439FC

[Anonymous]

Hi
Thank you, that was it. I just was in the Unfold UV Tool (the brush one), not the base Unfold UVs. 
The results are different than with the Unfold3D tho, but I'll be able to work with it 🙂
Thank you again 🙂 

[Anonymous]

This is not help. please fix

[jerome.lievens]

Hello,

After one year this shouldn't be a solution to give this is disrespectful.

"Don't use it" isn't a solution.

Time to fix unfold3D to be sure it's compatible with new technologies.

Legacy isn't a good algorythm to unfold a 3D object anymore.

Thank you to bring this problem up

[brentmc · Accepted solution]

Hi,

Older versions of Maya were patched to fix this issue with Ryzen CPUs.

You need to edit maya.env and add "MAYA_USE_ALTERNATE_UNFOLD_SHIM = 1" as described in this knowledge base article:

https://knowledge.autodesk.com/support/maya-lt/troubleshooting/caas/sfdcarticles/sfdcarticles/Unfold...

Note: It was addressed in this manner because these versions of Maya predate the Ryzen CPUs and the fix involved using a slightly different version of Unfold3D.

I also updated the solution to remove the old advice of using the Legacy version of Unfold because it is out of date information. 

--
Brent

[Maffnwy]

that isnt working

any new insights?
unfold works fine and then it doesnt. very annoying\

[q6v6p.simon]

Just solved the problem. One important thing I've noticed is you have to update your Maya 2020 first. And this doesn't mean that you have to update the software to the latest version like 2023, just update it to the latest version of 2020 will work. After update, you can then edit the maya.ev. I've been failed sooooooo many times until I updated maya software. This is the video shows where to find the update maya file: https://www.youtube.com/watch?v=5Liiw7qdIxU 

It is not in English but still works. Good luck!