Maya 2017 - Unfold not rescaling UVs for consistent texel scale

[Zliks]

Have the UV unfold functions (legacy and Unfold3d) been changed from Maya 2016 to Maya 2017? They are no longer re-scaling UVs to give multiple shells of the same mesh consistent texel scale. Am I just missing something simple?

I experimented on basic primitives using the same tools and settings and got completely different results between Maya 2016 and Maya 2017.

I have Unfold3D plug-in set to load and auto-load in plug-in manager. I see online that there is a bonus tools download available for Maya 2017. I have not installed it yet. Does it contain a fix for the Unfold tools?

My Autodesk Desktop App says "Your available updates are installed" and doesn't give me the option to update Maya.

Image attached - showing result after running Legacy and Unfold3D at the default settings. Notice that cap of cylinder is at different scale than shaft of cylinder.

Thank you!

[cornelh]

@Zliks

About updating, sometimes the Autodesk Desktop App doesn't work as expected.  You should be on Maya 2017 Update 2 to be on the latest update..  You can check your Maya version by clicking on the Help tap and about.. You can get the latest download via your Autodesk account under Maya "updates and add-ons".

As far as the UVs unfolding,  you seem to be correct on this one.. I was able to get this to work with Maya 2016 under legacy layout (prescale "object") Uniform.. etc..  Using these same legacy settings in Maya 2017 update 2 gives me UV's that don't really match uniformly accross the object.  I will check our defect database to see if this has been logged, and if not, I will be logging this in our system and hopefully it will be dealt with in a timely manner.  

Thank you again for bringing this to our attention.  Thanks

[cornelh]

@Zliks

About updating, sometimes the Autodesk Desktop App doesn't work as expected.  You should be on Maya 2017 Update 2 to be on the latest update..  You can check your Maya version by clicking on the Help tap and about.. You can get the latest download via your Autodesk account under Maya "updates and add-ons".

As far as the UVs unfolding,  you seem to be correct on this one.. I was able to get this to work with Maya 2016 under legacy layout (prescale "object") Uniform.. etc..  Using these same legacy settings in Maya 2017 update 2 gives me UV's that don't really match uniformly across the object.  I will check our defect database to see if this has been logged, and if not, I will be logging this in our system and hopefully it will be dealt with in a timely manner.  

Thank you again for bringing this to our attention.  Thanks

[Zliks]

Thank you!

[Anonymous]

Has there been any resolution to this issue?

Thanks.

[trevor.adams]

Hi,

Glad you brought this up, @Zliks - we've made a few changes from release to release that caused this inconsistency you're running into.  In Maya 2016, you had a new Unfold algorithm (Unfold3D), giving you the option to use either method (Unfold3D algorithm or Legacy algorithm (Maya 2015's Unfold algorithm)) to to unfold UVs.  However, the Layout algorithm was the same as it's always been in Maya, in this 2016 version.  That changed in Maya 2017 - we upgraded Maya's Layout operation by adding a new/modernized method/algorithm (Unfold3D), allowing you to choose between the old and new methods.  Lastly, Unfold has a "Pack" option that's On by default in Maya 2016 (when "Unfold3D" method is set).  It's still on by default in Maya 2017, but we turned it Off by default in the latest version, Maya 2017 Update 3.  Why?  I'll get to that in a second.  Let me first clarify why you're getting different results.

When you run Unfold in Maya 2016, you are first unfolding UVs and then (when the option is on), Maya runs a layout operation to "Pack" the UVs.  The important thing to know here is that the Layout operation being used when "Pack" is on for Unfold is the (now) legacy algorithm.  That legacy method had object pre-scaling on by default in this case.

When you run Unfold in Maya 2017, you are once again first unfolding UVs and then Maya runs a layout operation to "Pack" the UVs (by default).  However, since Maya 2017 has a new packing/layout method (Unfold3D), you're packing with a different algorithm and a different set of default options.

So that's why we turned "Pack" off by default in Update 3 - we want users to Unfold and Pack (Layout) separately, since Layout has a ton of options that users tend to tweak per-operation - and a lot of users were requesting that Unfold doesn't pack by default (especially when users are trying to unfold a single UV shell in an already-laid-out UV layout, for example).

All that to say, you can get the results you're looking for by doing the following in Maya 2017 versions:

1. Run Unfold with the "Pack" option disabled
2. Run Layout with the "Shell Pre-Scaling" option set to "Preserve 3D Ratios" (it's set to "None" by default)

Maya 2017 Update 3 also has new Texel Density controls so that you can manage all of this outside of the Unfold and Layout operations.

Hope that helps - let me know if you have any other questions and whether or not this solves your problem.

[Zliks]

OK first off, this is a huge overhaul of the UV tools! Thank you Trevor, this is fantastic.

But I still can't quite seem to find what I'm looking for. I would like the option to unfold selected UV shells as well as scale them to consistent texel density, all in one operation. I don't want to have to pack/layout in order to re-scale UV shells. And I don't want to have to re-scale as a separate step than unfolding (though the UV toolkit -> transform -> texel density tools are great!)

Yes it's totally possible to do what I want but it requires more clicks. I feel like consistent scaling should be part of an unfold operation, or at least a toggle on/off if unfolding should rescale. While still only operating on the selected UVs or selected shells, without packing/laying out shells. Am I missing this somewhere?

All that said, the new tools look great, and have definitely rendered my request more nitpicky! Thanks!

[trevor.adams]

Thanks @Zliks.

To clarify, the Unfold operation by itself doesn't do any scaling.  Historically (pre-Maya 2017 Update 3), 'Pack' was enabled by default for all Unfold operations.  And historically, the packing algorithm that was used prior to Maya 2017 was Maya's 'Layout UVs' operation, which pre-scaled the UV shells the way you currently want them to.  So, with all that considered, you were essentially running both Unfold & Layout operations in a single step.  And again, that bothered a good majority of users (users wanted to unfold without affecting the current layout of their shells, by default), so it's no longer happening in current versions.

This is a multi-faceted issue because of multiple changes that happened between then and now.  I just wanted to clarify that if we were to address anything here, it wouldn't be adding a (pre)scaling option to the Unfold operation, simply because that option only really applies to Layout ("Pack").  That said, I do like the combo of Unfold/Pack with proper pre-scaling - I agree with you there.  One way to address this would be to add sub-options for the 'Pack' option in Unfold, one of which would be to enable/disable 'Shell Pre-Scaling' (and yes, we could set that to Preserve 3D Ratios by default).  And we should probably just rename 'Pack' to 'Layout' to remove any further confusion that these are separate things (again turning on 'Pack' is just adding a 'Layout' operation to run after the Unfold process is done, with default options).

I've added the improvement request in our system.  Thanks again, but continue to let me know if you think I'm misunderstanding something here, from your vantage point.