UV optimisation??

nyffix

Hi! So I've watched videos from flippednormals and in one of their unwrap videos they mentioned UDIMs and I used them on two of my models.. but then this morning i was like ' is this really okay for games? ' and i searched this forum and I saw a lot of people being like ' no, it's not okay ' and now I understand it's more of a movie/film practice than a games one.

So my problem is. How do I optimise a UV set? Does anyone have any resources I could look at because I'm having a hard time understanding how to stack UVs and also keep a good resolution on characters. Is it indeed better to have everything on 1 map than multiples?

I've attached pictures of what I'm working on now and the UVs for it in hopes someone could give me some pointers on how I could do things better.

Thank you!

Edit: I use Maya and this is for my portfolio if it matters.

Neox

there is no real clean rule, it walways depends on your final output

considering your avatar is the style you are aiming for, you could actually approach it in a lot less standard way to achieve higher resolution textures

check the GuiltyGear XRD talks on that topic.

but yeah, the first thing i would do. apply one checke material and make sure all your assets have essentially the same texture resolution / texel density.

then you can puzzle those really quickly into on 0-1 space and see how pixelated it looks. is it acceptable? then you are good. Is it not? Then think about what you can do

you could for instance make the head bigger as it's a huge focus on your character. or the hands if first person is your goal. the arms and hands could also be their own sheet (like udim) to offset the load of the rest of the character in first person view etc.

you could certainly straighten your UVs more to be able to stack them better. the hands eat a ton of UVspace. a lot on that first sheet is so wobbly, if you straigten things some more you can gain some resolution, in exchange for slightly more stretching. Depending on the case.

you could take a look at ripped game content on platforms such as sketchfab. there are tons of overwatch assets for instance, including stuff i wouldnt be allowed to share myself. buzt there you have all that data and can analyze it.

nyffix

@Neox Thank you so much for taking the time to answer. I will have a look at those overwatch characters once I get back from work. 

By straightening the UVs do you mean manually make them more of a grid? Or simply making sure they are straight themselves as they are presented currently? 

My aim is to make a small fantasy scene with this character and another 2 (one of which i will need to rework the textures of ) where they're sat on logs by a fire or something similar with small animations. 
I will post the other 2 models here once I can.


I

Neox

you don't have to straighten manually. you only straighten the outsides manually and then relax the insides.

dependent on the software you are using you have various possibilities at hand. One thing i LOVE about 3dsmax is, that i can weld UVs even tho the verts are not connected in the mesh. What sounds like a bug, gives me a ton of flexibilitiy when using it.

here are a few examples of how that works. but in other tools you can straighten and pin, to do similar things

http://www.polyphobia.de/public/advices/bananafingers.gif

http://www.polyphobia.de/public/advices/Oface.gif

http://www.polyphobia.de/public/advices/UV_straight_01.gif

Straightening has many positive sideeffects for games. Not just that UV puzzling is easier to handle.

Say you want to make LOD (Level of Detail) models, you can kill loops without worrying that you will create texture seams.

You can also paint straight lines without aliasing issues happening.

Neox

lemme actually just prep our internal guide on the topic

Neox

http://www.polyphobia.de/public/advices/uvstraightening.pdf

meh export didnt wanna work for unknown reasons, so layout is bodged and no animated stuff. but i posted the important stuff before

goekbenjamin

Neox said:

http://www.polyphobia.de/public/advices/uvstraightening.pdf

meh export didnt wanna work for unknown reasons, so layout is bodged and no animated stuff. but i posted the important stuff before

Just awesome! Danke dir vielmals!

nyffix

@Neox
Absolutely bless you!! Will go through the document once I can access my pc and post here when I've made some changes!! Thank you so much! 

csprance

Banana Finger Syndrome

Neox

csprance said:

Banana Finger Syndrome

it is what it is, also i hate bananas. so that shit better goes away!

Dethling

Thanks a lot Neox for the breakdown, this is VERY helpfull!

nyffix

So I said I'd post here once I've made some changes to the mesh and I have reunwrapped most of it! 

Let me know how else I can improve! Thank you!

Ended up breaking it off in hair and the rest!

Neox

i think you could do a little better closing those big gaps here and there. but its on a good way.

what i think atm is the oddest is the hair.the mesh is a mix of a handmade lowpoly on the front part and a very very dense zremesh for the back? for one i think the loops look pretty crazy and not great for rigging (depends on what you wanna do with them, might also be okay) but is insanely dense compared to the rest of the model. if you killed 50% of those tris it would not look worse and you could spend those on deforming areas, the shoulders, the ellbow, hip and knee joints and maybe the face.

for the flow of the lowpoly hips, i think you could take another look on the wireframes from existing games. i dont think what you did there looks really nice fo deformation and also in terms of density. you will have a tone of movement around the hips

nyffix

Ill give it another go! Thanks!