Overlapping UV's: do you care?

Assuming you aren’t going to use a model in a game, do you care if a beautifully textured model has overlapping uv’s? I think there will be some people who want them non-overlapping simply because it looks neater. But for rendering, as far as I know, there’s no reason to care (assuming no texture painting). I have a whole city full of models using 10 or so PBR materials, and it would be a massive waste to make each arch on a building, for example, (currently mapped to the same place on a UV), have it’s own space. I’ve joined a bunch of modular blocks, then merged multiple objects into one, so yes, there will be many overlaps. Thoughts?

Overlaping UVs are bad when you want to make unique texture on mesh eg. by baking.
If you just apply texture eg tiling, or trim sheet on model its nothing wrong in overlaping UV and its even expected. Even baked assets are made with in some extend overlap (eg mirrored object).

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No.
You can overlap UV’s : that is a common practice.
And if encounter a problem with with method, you can create variance by mixing your texture with another one using another UVmap.

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Thanks. I just wonder, as Turbosquid (and I’ve been selling there for more than 10 years), is obsessed with non-overlapping. Even Kitbash proudly displays it’s non-overlapping uv’s. Just seems like a massive extra step to re-uwrap a build made of tiling geometry.

If it’s non overlapping, it already has a setup suitable for baking. It depends on the game engine it’s going to be used I guess. You may have the option of special purpose UV layouts for light maps, or it may have to use a single channel. And “looking neat” isn’t just about the visual appeal, but how easy it is to work with those UVs in any software. What if the software shows all UVs regardless of selected faces and it’s all kinds of messy?

If people want to freely edit textures (or create textures), then they need non-overlapping UV.

Here, let’s say you make a fully textured character model, with mirrored UV, and sell it, and then the person that buys it wants to create an asymmetrical tattoo on that character. To do that, they’ll have to either use decal mesh techniques or create their own UV. If the model they bought has non-overlapping UV, then part of the work they’ll need to do is already solved.

I don’t know exactly what obsessed means in this context, but it makes perfect sense to me that a model with a high quality, non-overlapping UV map has added value over one without.

But of course, Turbosquid doesn’t have opinions; people have opinions. There are actual people that are saying this to you. Why not ask them why they want non-overlapping UV? (Some of them, it’s probably just a knee-jerk thing where they don’t know why, but for others, I think you’ll find reasons similar to the one I mentioned.)

Yes, that’s what I’m doing here. For props and characters, it makes sense to have non-overlapping. But for a bunch of tiling geometry buildings…it sort of defeats the purpose of tiling geometry. So, yes, I’m trying to get a sense here of if it matters. That said, it’s entirely academic. I’ve sold more than $50k on Turbosquid, overlapping and non. Weirdly, I keep selling ancient models that are crap in every sense, with few complaints. I can’t go back and clean that account up (I have two), as it’s got 1000 plus assets, so I just deal with issues as they arise. I’m trying to keep my new account up to date, so I want to know what’s important and practical.

For close up shots I prefer non-overlapping UV’s because I can go into Substance Painter and really tweak the textures without worrying about weird stuff happening.

For distant non-detail objects (say for instance a cityscape) I tend not to care too much.

Ian Hubert’s entire workflow uses overlapping UV’s and it seems to work fine for what he needs to do – but I think he’ll be the first to admit that it’s not suitable for close up work.

I mean, it’s the same thing if they want to put some graffiti on a building. Yes, there is definitely added value from having good overlapping UV as well, to improve texel density. But assuming you have some well laid out UV, and your target isn’t game use, it doesn’t seem to me that it would be that hard to add an extra UV map where you just hit ctrl-a, ctrl-p to make it non-overlapping.

Could the client do that as easily? Well, yes, but I would imagine that there’s a decent chunk of people purchasing that are scared of/unfamiliar with at least some modelling operations (because otherwise, they might just be making their own models instead of buying them.)

Looked him up (Ian). He’s pretty good…HAHAHAHA! He’s amazing, clearly. Well, good. That’s exactly what I’m doing. Building, big cityscapes.

Yes, I get that. In any event, things are so specifically placed on my textures, I can’t just pack them and have them randomly placed (stone blocks ending at the ground and being 1’ tall etc). But I’m glad to hear more reasons and ideas.

I’m not saying to replace your overlapped UV. Like I said, there’s a lot of value in overlapped UV as well. If you baked a city to a lightmap pack, your textures would turn to mud anyways. Leave the textures mapped to your overlapped UV, and offer a no-overlap UV in addition.

At least, it’s something you could do. It sounds like you’re doing pretty well for yourself, and I don’t see why you’d bother worrying about it. If it ain’t broke, don’t fix it, right?

Right. Just curious. I see huge value in tiling geometry, but when you join 10 arches, 5 straights, 3 windows…SLOPPY UV’s. In the arches, 2 models and 3 materials. Joined all together…ugh. But here, it clearly doesn’t matter. I’ll admit that I wish there was a way Blender could magically reorder islands and keep the appearance and resolution, because I HATE sloppy. So…that’s why I’m asking. It’s a case of “Please tell me it’s ok!” Hahahaha!

I pretty much re-seam/re-UV all the models that I purchase since far too many of them seem rather sloppy. I can’t model worth crap, but I can handle redoing the UV’s to my specifications without issues. But yeah, I’m a bit odd in that way (actually in several ways…but I digress).

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I think it’s okay to have sloppy UVs. At the point that you’re looking at a really detailed model, you’re no longer considering exporting a UV map to paint in GIMP anyways. You’re using techniques where the actual layout of the UV map is abstracted away: baking, texture painting, SP.

Trying to make super-orderly UV maps doesn’t strike me as a great way to spend the limited amount of time you have to make a great model. I’m sure there are potential clients for whom orderly UV is really important, but that’s not for a good reason. (Like somebody who judges an electrician’s competence by the cleanliness of their truck, it’s mostly because they don’t have the skills they’d need to identify meaningful criteria.)

I suppose that placing like with like is still nice because of margins and mipmapping. But there’s a limited amount of work I’m willing to do to address that, and I’d rather wait until I have a visible problem to fix it.

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Yeah, I pretty much always just use autopackers these days. Density and keeping margins is the important part for stuff like Substance Painter.

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It can cause some serious issues when baking various maps in Substance Painter. Believe me, if I buy a model and it’s good to go in Substance Painter I’m not complaining. But if I bring the geometry into Substance Painter and my AO’s Curvatures, etc. are a mess, then I gotta go back and re-do the UV’s. Thankfully I use Houdini for that type of thing which has some great UV utility nodes.

So I think there’s two basic aproaches-
You can either treat your materials as - materials. You use tilable textures and they’ll tile a few times over the mesh,
OR you can have a single set of textures for an object - one colour, one metalic, one roughness, one normal - and that takes into account dirt, materials, everything.

There are also mixes of the two aproaches with multiple us - or ones that tile one texture and have the other untiled within the same uv.