UV Map advice

Hi guys. I’m still trying to work out how to do nice UV maps for substance painter and am practicing making nice seams. My worry is that when I have a molding type piece, because there’s quite a few faces in it, when the UV island is shrunk down to fit into the UV map with all the other pieces it looks like the UV island is so cramped up. Is this okay? Or is there a different way to go about this?
You can see in the first picture an example of a model. Then in the second you can see this curved piece unwrapped. However once I’ve unwrapped this whole model, squishing all these UVs into the UV space, you can see on image 2 how tiny some of the faces will be on the UV island. I imagine it’ll be even smaller than that… And this is not exactly a big model, or a very detailed one.
Does anyone have any suggestions? Or am I worrying about nothing? I intend to texture in substance painter.


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Thanks man that looks really interesting. Is it necessary to use this in this situation though ? It seems most people that use this are doing very high poly sculpts. All my model is is a fairly small porch. It just seems the UVs will be tiny once fit into the space .
My main thing I’ll do is model buildings for use in a strategy game, and I’ve just not heard of this UDIM for these kind of models, what’s your opinion? Or can I make my UV map bigger ? I’m a complete novice with UV mapping at the moment so any advice from anyone is welcome

Maybe it doesn’t actually matter how small the face is because it’s basically just making up a long shape - it’s not like the texture with be placed on each face as a new image … I think I’ll just try it as it is - also can I place these identical islands onto of each other ? As they will use the same texture

You may repeat the texture but with an offset:

Thanks man. Yeah good point about the unseen faces ! I’ll get rid of them. I’ve heard more and more about this offset by 1 thing ? Would you elaborate? Finding it tricky to understand what people are meaning … and what do you think to how small my UV island is for the main part of the curved shape ? Is it too small?
I don’t quite understand what you’re trying to say with the arrows either
And to the curved pieces , I mean like actually overlapping them ontop of each other to take into SP ?

Offset: if the UV rectangle of the wood planks or beams are all set to 0,0 to 1.0,1.0 (for example) then of course all surfaces looks the same and unnatural. If you make them a little smaller than the actual UV texture rectangle and offset them a bit (while not using the whole UV space if you have different texture in it) yu can use say a texture 2-3 times larger then one beam but texture all beans slight different.
Relations: too small/big depends on you texture (handpainted/realistic) and the usage (background prop/ close up detail)

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What Okidoki means is that you can use overlapping UV faces with a bit of an offset.
For many situations it is a waste of UV space to give each face its own personal UV space. Do not be afraid of using overlapping UV’s they can be very useful to save texture space.

Right , so they would sorta look like a deck of cards splayed out to one side if they where all rectangle islands ?

Yes, but more like scattered on top of each other than splayed out to get some randomness into the texture.
You can move the islands around in the UV editor and preview the results until you are satisfied.

Okay, well I’m using substance so I can’t move islands around without going back and forth from blender I don’t think.
And do I just bring everything into substance the same as normal even with these uv overlaps ?
Thanks for the help by the way!

In that case you would have to set out the overlapping UV’s beforehand in blender. I do not use substance but I am sure you can import an overlapping UV map into it.

The overlapping method only works if you do not mind different parts of the model sharing parts of the texture.

It all depends on your final intentions, If you want to paint some gratify on afterwards it would not be so good to overlap (or at least not those faces).

Thanks man I appreciate the advice ! Will be giving it a test out soon as I got time