UV Set Confusion

[t_smith5]

Hi

Has something changed with an update or something...? I swear when I've used UV sets in Maya before, I could get it working no problem. I could have sworn that you selected your recquired UV island, loaded up the UV Set Editor, clicked on New, and then hit Update and it was sent to the new set...? Or you click on copy and it goes to a new set...? Whenever I do it now, nothing seems to happen. I'll click on the new UV set, but it doesn't appear to isolate/show what should be there. In other words, it doesn't hide everything else I didn't select/move and only show what I did. Everything is in the same place in each set.

It tends to do it if I go to UV Sets > Copy UVs to UV Set > Copy into New UV Set, but with the current pieces I'm working with at the moment, it isn't. 😕

[t_smith5]

Can someone please confirm whether this is working as it's supposed to, because this really seems like it's broken to me. It makes no sense. I'm selecting all the UV islands I want to put into a new set, and they're still showing in the first set - UV Channel 1. Or, all parts are moving to the new, except one. Or, I select everything else except the ones I want and copy them into a new set, but when clicking back and forth between the two sets, it's hiding/showing only a few random islands. Clicking on the new set makes them disappear, and then clicking on the original brings them all back together. But how the hell do you toggle between the sets so only the relevant/moved islands show...?? It's really frustrating. I've even tried deleting the history to see if that fixes the issues, but there's no change. 😞

https://imgur.com/a/8dsGBmQ

[mspeer]

Hi!

What Maya version are you using?

I can't see any problem here with Maya 2020.4 and Maya 2022.

Creating a new UV Set creates an empty UV Set, that's correct.

Copying UVs from a UV Set into a new UV Set does not remove any UVs from the old UV Set, so that's also correct.

Based on your video you have multiple objects selected, so that may be the reason why there is some confusion about what's shown in UV Editor.

Please try your steps with only one object selected to make sure it works as expected.

[t_smith5]

Hi. Thanks for the reply. I'm currently using Maya 2022. I've tried just selecting one UV island and adding it to another set, but though it disappears, I don't know how you can access it on its own. I've gone through each object and completely removed any UV sets I've made previously, so they all have UV Channel 1.

I've just tried selecting one UV island and copying it to a new one, and instead of moving that, it looks as though it's transferred all of the other pieces I would have selected with it onto its own set. The one I did select still only appears on UV Channel 1. Second time - I selected one and added a new set, and it's moved it and all the other pieces I didn't select, but where is it...? How to you access them on their own set...? I've still seeing all the other pieces. 😵

[mspeer]

Hi!

Without knowing what UVs depend to what object I can't answer your question.

If you copy UVs to a new UV Set you will see the copied UVs + all UVs from the other objects you currently have selected, so for example if you copy all UVs from one object, then the display will not change.

Please provide a scene-file with the exact steps how to reproduce this cause here it works as expected even when working with multiple objects selected (which I would not recommend as it's confusing, so better work only with one object at once.)

[t_smith5]

I've attached a save file I've set up. When you select all meshes, all the UVs should be within the first grid. I want to try and get specific parts into their own set. In Max, I'm able to select those UVs and move them into channel 2. I can also switch between them via their material IDs. Is there any way of being able to do something like that in Maya? Don't worry about putting the specific UVs I'm after anywhere, you can move whichever. 🙂 I'm just trying to get to grips with how it works in Maya.

Okay, so I get that copying UVs to another set will still show you the copied ones and the ones not moved. But I don't get, and I want to know how, you can see those copied/moved UVs so they're on their own. Separated. So I can just focus on those. I swear I've been able to do it in the past...

Thanks

[mspeer]

Hi!

Thanks for the file, this helped to understand what happens.

You can select multiple objects in Maya and you can edit all these UVs at once, but when you copy UVs into a new UV Set this works only on one object.

What you do in the video is moving some UVs, this changes the UVs for the basic UV Set for all objects, then you create a new empty UV Set for one object, because of this some UV shells are missing (the new mask set is empty) and only on little UV shell is kept at the position, because it's from an other object that still shows the basic UV Set.

When you use copy UVs into a new UV Set this works, but as you moved ALL UVs first and then copied them to a new UV Set, they are now at both UV Sets at the same position.

If you want to isolate some UV shells of one object, then you should only select/copy the UV shells you want in the new UV Set and if you want to remove them from an other Set you need to delete them there.

If you want to create/switch the UV Sets for all objects at once, so for example that you get multiple UV Sets per object, but only one of these contains the UVs, then you need to select all Objects in UV Editor (UV Sets -> Object -> ...) or you need to use the UV Set Editor.

[t_smith5]

Thanks for trying to explain. Unfortunately, no matter how many times I re-read through your post and keep trying, I'm still struggling with this. 😞 Right when I think I've understood, something else happens that pulls the rug from under me. Prior to uploading that save file, each UV was added to more than one set. I went through each of them and removed them. So now they're just under the default one, which is UVChannel_1. However, despite that, I'm selecting everything of the character, except the mask, and copying them to a new set called Tiny Tina. So the UVs should be in both the default set AND the new one, correct...? The problem is, it keeps giving me this error about the skirt:

It's random things like this that throw me off and make me question whether there's a bug. I've checked and re-checked to make sure the skirt piece doesn't have another set. It did have one under the Tiny Tina name, but it was removed. And the object doesn't list any other set. They're all UVChannel_1. I've even tried deleting the history and updating the UV Set Editor. Even if I try a different name, I still get the same error.

If I select the skirt and just copy that to a new set, it automatically adds it to a new set called Tiny Tina. Even if I delete that set and hit Update in the Set Editor, and it returns with every other UV, it still gives me that error if I try to copy everything into a set. Even if I select the skirt on its own, and copy the UV to a new set with a unique name, and do the same for the mask, if I select both objects, they still combine together. There's no way of clicking on each of their own unique sets and switching/isolating between them...? Like you can in 3ds Max...? Even the UV Set Editor doesn't come up with the two individual sets if both objects are selected. Also, even if I select the set the UV has been moved to, when every other object and UV has been selected and can be seen, clicking on isolate doesn't hide everything else but the object. It hides everything. Same if I select the default set UVChannel_1 and click back to the new set. Nothing shows. Everything disappears. The contents of that set aren't isolated from everything else.

Maya's UV Sets make absolutely zero sense to me.

[mspeer · Accepted solution]

Hi!

If you select UVs from more than one object, then you get this error, again Maya can only create a new UV Set based on existing UVs for only one object at a time, so it does not make sense to select more than one object.

Why do you select all objects?

I also still don't understand what you mean with "isolate".

1. If you want to view only the UVs of one specific object, then simply select only one specific object.

2. If you want to have all UVs of all objects at a unique UV space, simply move them. There is no need for any copy process or further UV Sets.

3. If you want to have some UV shells for ONE SPECIFIC OBJECT at unique UV Sets, then simply create a new UV set with the UV shell selected.

Theses are your options and they all work without any problem.

Maybe you want all objects to use the same UV Set, then you need to combine all objects first.

[t_smith5]

Right, okay. That's cleared up some of the confusion, so thanks for that. 🙂 This is an area I feel 3ds Max excels at compared to Maya. In Max, I tend to select all objects and apply a UVW Unwrap modifier to them. This way, I can move/organise the UVs whilst seeing all of them, so then I can determine if some are too close, overlapping, too big, too small etc. It's quite difficult to tell if you can only organise the UVs one at a time. Plus, if I want to hide the UVs I don't want or to add them to their own set, you can select them and assign a new channel to them. Or switch between UV sets based on material IDs. I'm surprised Maya hasn't adopted a similar thing. 😕

By 'isolate' I just mean being able to access and only see the UVs that have been copied/moved to another set without seeing all the others. Plus, there's the Isolate option in the UV Editor. 🙂

[mspeer]

Hi!

You can do this also in Maya, the restriction for one object is only for copying UVs (,which does work when multiple objects are selected, but you can only copy UVs of one object at a time).

Example workflow "Duplicate + Delete", which does not require to copy individual UVs and works with multiple objects and UVs:

[t_smith5]

Ahhh. But. I'm still not getting it. 😅 😖 I'm duplicating the UV set, so there's the UVChannel_1 and the new set both containing all the same UVs, but then, if I delete all the UVs I don't want in the new set, they're being deleted from the UVChannel_1 too, except for one random object/UV. 😖 Is this another case of only being able to select one mesh/object...? Though your GIF is showing multiple objects selected...

EDIT: Wait. I think I'm getting it. I take it it's mandatory to select the objects from the Objects box, to the left of the UV Set box, instead of right clicking, selecting UV Shell, and hitting delete...? That would explain why I sometimes get a random UV in a set despite selecting all the UVs and hitting delete - it's because of an object selected in the Object box! Whenever you've mentioned that you can only copy a UV from one object at a time, I thought you meant if/when you select a mesh in the scene. But you were referring to the Object box. 🙂

I take it though it's also mandatory to put the UVs from a specific set into another UV grid...? So the UVs from both sets don't overlay...? This comes back to 'isolating' again. Is there no way of getting the UVs from one set to disappear when you have another set selected?

[mspeer]

Hi!

"..it's mandatory to select the objects from the Objects box, to the left of the UV Set box"

- Correct.

"...it's also mandatory to put the UVs from a specific set into another UV grid...? So the UVs from both sets don't overlay...?"

- No, the position of the UVs does not matter.

In my example I just hit the delete key on the keyboard.

"Is there no way of getting the UVs from one set to disappear when you have another set selected?"

- What? (It already works like this.)

If you select a new UV Set, then only the UVs of the new selected UV Set will be shown, so other UVs will "disappear" visually, this is the normal behavior.

If you want to remove UVs from a UV Set, simply delete them there.

Every UV Set is a complete independent UV mapping, just arrange your UVs to your likes and then you can view a specific layout just by selecting the corresponding UV Set.

[t_smith5]

See, this is where I suspect there’s an issue somewhere on my end. I’m pretty sure once I’ve put the UVs I want into their own set, clicking on that set isn’t hiding the others and only displaying those. It shows everything. And if I delete the UVs I don’t want from that set, but they’re still in the default one (UVChannel_1), they get removed from there too. I’ll go back and try again and report back on whether it works or not.

[t_smith5]

Yeah, so I had all meshes selected, so all the UVs were showing, I selected the psycho mask from the Object list, hit Duplicate UV Set, selected every UV except the mask pieces, selected the psycho mask in the Object list, selected the new UV set (uvSet1), and hit delete. All the other UVs went, but they're also gone from the default set - UVChannel_1. 😕

I take it when using Duplicate UV Set, you can't just select one object from the list, but all of them...?

I can't seem to select all objects from the list with Shift click, and then press Ctrl and click on the object I don't want deleting either. I would have thought that would have deleted everything except the unselected object. That just deletes everything, including the UV set.

I've also tried selecting all the UVs I don't want, in the Object box, but hitting delete doesn't remove them. So I'm guessing it has to be the UV shells you need to delete, which is what I keep trying. Or, do you need to select everything you don't want in the Object list, and then select the UV shells...?

EDIT: Doing the above seems to work - selecting everything in the Object list, and then selecting/deselecting the UV shells, but clicking on each UV set still isn't hiding the others. The only time that works is if everything is selected in the Object list. Do they always have to be selected then...?

[mspeer]

Hi!

Based on your video as you only selected one object you only created a new UV Set for one object and if you delete other UVs from other objects you deleted them from their main UV Set as the other objects are still using the main UV Set.

Try a simple example as in my scene with just 2 objects and you can clearly see the difference between your workflow (viewing all object UVs, but changing only the UV Set of ONE object) and my workflow (viewing all objects and changing UV Sets of ALL objects).

[t_smith5]

Hi. Okay, I'm starting to get it a bit. In the Screencast I've shared, is that the sort of thing you mean...?

I take it you have to select the empty (default) set, once the UVs have been deleted from it, in order to hide the ones you don't want...?

EDIT: Looks like the forums are being a bitch again. It won't let me upload the Screencast. Despite the video being finished pending, it keeps complaining the HTML is invalid. 😕

[t_smith5]

There's still confusion with my character model though. I would happily do a video, but I can't seem to share them. Surely, if I just select the mask object and mesh, duplicate the UV set, delete it from the default one, and then select every mesh, pick the mask from the list of objects, and then pick its new set, that it will only contain the mask's UV...? After all, that's the only object that was selected from the Object list... But it doesn't appear to be the case. Selecting that new UV set, it's still showing everything else.

I added that mask to a new set just by selecting the mask mesh on its own. And nothing else. If I try and select every UV using UV Shell, except the mask, and I have the new set selected, if I hit delete, it just deletes them completely. From both sets. None of the other objects are listing any other set - just UVChannel_1, so I don't get why I'm still seeing all the other UVs.

As I said before, if I select every object from the Object list, and then click between each set, they disappear/appear as they should. Just not sure if that's the correct way of doing it though.

[mspeer]

Hi!

"Selecting that new UV set, it's still showing everything else."

Sure, as all other objects still use their default UV Set.

The mask shows the UVs of the new UV Set and the other objects the UVs from an other UV Set.

In Maya you can view the UVs from multiple Objects and you can change the UV Set for every object individually.

You created a new UV Set only for the mask and all other objects only have the basic UV Set.

So when you change the UV Set for the mask only, then of course still all other UVs are displayed.

If you then delete UVs from other objects they will be of course deleted from their UV Sets as they still use the default UV Set.

In short:

You only create and switch the UV Set for the mask and not for all objects.

If you want to create a new UV Set for multiple objects or you want to select a specific UV Set for multiple objects at once you need to select all Objects in UV Editor (in your screenshot only one object is selected in UV Editor).

That's all.

Please check again my previous example where I marked with yellow what's important.

Here some more frames, that should make it clear, if not I will run out of options.

[t_smith5]

Based on your GIF, I was right then...? That you need to select all the objects in the Object menu in order to toggle on/off the UVs you do/don't want to see...? That you need to select all the objects in order for their respective UV set to show in the list...? And deselect what isn't...?

And when you say 'Sure, as all other objects still use their default UV Set', that's where it throws me off. Because if those UVs are still existing on the default set, whenever I've tried to delete them from the new set, they've been getting deleted completely. From both sets. I've tried selecting all objects and then selecting their shells, but I've not been able to select the new set they're on as it can only be accessed by selecting the psycho mask object.