topic 3dsmax 2021 'Forgettin' UV mapping in 3ds Max Modeling Forum

3dsmax 2021 'Forgettin' UV mapping

Migsey_UK — Wed, 01 Apr 2020 14:07:37 GMT

Hello Everybody.

In my line of work, I constantly need to bake textures to make solids look better in an environment similar to a gaming one.

One of the features I was very happy to see in 2021 is the ability to queue the rendering of multiple baked textures. A real blessing. However, after rendering a few textures and placing them on the geometry, the final result was far from the expected one.

So the workflow is as follows: select geometry, apply UNWRAP UVW, and from the UV editor, choose FLATTEN MAPPING. the faces get all separated and laid in the UV space as expected. Then bake to texture and all is good. Now I re-adjust the lighting in my scene and then go to bake to texture again when I check the UV mapping, 3dsmax reverts to the previous state before FLATTEN MAPPING the object. So, picture 1 (UV END) shows the geometry UV mapped and the second picture (UV START) shows the UVs when I check them after the baking is done. It is like 3dsmax didn't save the UV mapping and it never happened. Any ideas?????

Thank You very much for your attention!

Re: 3dsmax 2021 'Forgettin' UV mapping

10DSpace — Wed, 01 Apr 2020 16:51:19 GMT

@Migsey_UK

When you finished with your flatten mapping in the Unwrap UV Editor, did you collapse the Unwrap UVW modifier to the mesh on the stack? This should lock in the finished Unwrap UV editing. So if you did any further tweaking of scene lighting or anything else the UV Mapping should definitely not change if you were to subsequently reapply the Unwrap UVW modifier and look at it.

I am still on Max 2020.3, but I have had circumstances (sorry, can't exactly remember the situations) where not collapsing the Unwrap UVW editor and then returning to it after making other changes in the scene, lost the Unwrapping changes I had made. Just something to try if you haven't already done so. Hope this helps.

Re: 3dsmax 2021 'Forgettin' UV mapping

Migsey_UK — Wed, 01 Apr 2020 17:28:56 GMT

Hi There

Thanks for your reply. In 2019 I never collapse the stack as many times I have to go back and do some changes. I did some investigating and it seems that this is not a new thing. Someone has already reported it in 2018. the workaround seems to do exactly what you say. Once UV mapped to collapse the stack and thus locking the UVs. This is very weird cos I never really collapse the stack. It feels to me that it goes a bit against the non-destructive layering idea. For the moment I am also experimenting with saving the Uvs to an external file.

Thank you very much for your reply and time reading my posting!

Re: 3dsmax 2021 'Forgettin' UV mapping

Anonymous — Thu, 02 Apr 2020 19:08:55 GMT

It was fixed in some 2018 update, but now it seems to surface again in 2021 release.

So some regression. Have to report as bug.

Re: 3dsmax 2021 'Forgettin' UV mapping

Migsey_UK — Thu, 02 Apr 2020 19:16:41 GMT

Hi there.

Thanks for your reply. Is there an official channel for bug reporting?
All the Best

Re: 3dsmax 2021 'Forgettin' UV mapping

Anonymous — Thu, 02 Apr 2020 19:25:49 GMT

Sure, the official channel:

http://download.autodesk.com/us/support/report_a_bug.html?SelProduct=3dsMax

Re: 3dsmax 2021 'Forgettin' UV mapping

Migsey_UK — Fri, 03 Apr 2020 08:33:37 GMT

Many Thanks

I have submitted it! If it is a bug and nothing I am blindly missing, I hope it gets fixed soon!

Re: 3dsmax 2021 'Forgettin' UV mapping

10DSpace — Fri, 03 Apr 2020 15:48:21 GMT

@Migsey_UK

It feels to me that it goes a bit against the non-destructive layering idea. For the moment I am also experimenting with saving the Uvs to an external file.

Until a fix is available, the other option for working non-destructively (which I am sure you are well aware of) is to make a copy of the model with the complete stack so that you can always return to that state of the model even if you have to work on a separate collapsed version to achieve a certain objective. One reason that this is seen as a clumsier workflow is that it takes multiple steps (Clone, rename backup, Hide Backup). So I wrote a script (attached) that automates this process which I use when I am forced to collapse the stack for whatever reason. The script does the following:

Makes a copy of the selected object and names it as [selected Object’s Name]_Bak_Date_Time
Places the Backup Object in a separate Layer Named "Backup"
Hides the backup so that you can go on working on the selected Object

By making this a 1 click process and organizing your backups in a single layer with a timestamp for each backup, I find it makes me far less hesitant about collapsing the stack.

Also, a few other personal thoughts on the term "non-destructive" and the sometimes negative effect it has had on my workflow.

If the only things on the stack are an Unwrap UVW modifier on top of an Editable Poly, then collapsing the Unwrap UVW modifier is not at all destructive; adding the Unwrap UVW modifier back at any later time returns you to the Unwrapping you last did before collapsing the modifier. So nothing has been destroyed.
If you have a more complex stack below the Unwrap UVW modifier, then making a backup of the object with the complete stack intact will allow you to return to where you were. So again here, nothing has been destroyed.
This one is admittedly a little philosophical and a bit off topic. Personally, I have sometimes hesitated too much in exploring alternative model designs because I worry about preserving an increasingly complex "nondestructive" stack, renaming the various edit poly modifiers so I can remember what each one does. Also, maintaining the stack has tended to defer artistic decision making (for me) for the sake of “flexibility” in the future. In actual practice, I find that if I make a copy of the object to preserve the full stack with my little script, I then proceed more boldly, making those artistic decisions and rarely go back to previous versions. Having the previous versions in the Backup layer with the naming convention described above makes it easy to delete them, which I invariably do.

I am not trying in any way to minimize the need for a non-destructive workflow for much of the modeling process, but wanted to offer the script as another way of helping to do that in cases where collapsing the stack is necessary or expedient.

Anyway, I hope this is helpful in some way.

Re: 3dsmax 2021 'Forgettin' UV mapping

10DSpace — Fri, 03 Apr 2020 15:53:56 GMT

@Migsey_UK

For some reason the script did not attach to previous post. Hopefully, here it is.

Re: 3dsmax 2021 'Forgettin' UV mapping

Anonymous — Fri, 22 May 2020 16:29:51 GMT

I am having the same issue. Seems to be a bug.

Re: 3dsmax 2021 'Forgettin' UV mapping

Migsey_UK — Fri, 22 May 2020 17:01:52 GMT

Good to know that it wasn't something I was doing wrong 😉 . I reported it a while ago but had no answer. For the moment I am collapsing all UV mapping which defeats the purpose of the Non- destructive workflow but at least I know what I get.

Thanks for replying!

Cheers

Re: 3dsmax 2021 'Forgettin' UV mapping

Anonymous — Thu, 09 Jul 2020 07:28:40 GMT

@10DSpace

Impossible to clone the geometry to make a backup as doing so breaks the UV's - same with mirroring - this is a really irritating bug and means I am having to collapse the stack and perform a destructive operation for something that I'm pretty sure wasn't broken in previous versions.

I have reported as a bug through the correct channels but thought I would bring this to attention as there is no workaround other than collapsing the stack!

Re: 3dsmax 2021 'Forgettin' UV mapping

10DSpace — Thu, 09 Jul 2020 13:11:38 GMT

@Anonymous

Impossible to clone the geometry to make a backup as doing so breaks the UV's

If simply cloning your object breaks the UV's in Max 2021, then that is a new bug other than the one originally described above. Cloning certainly does not break UVs in previous versions of Max.