UVs: Orientation VS Spacing

goekbenjamin · Nov 2018

Goal: prepare uvs for a game ready model to generate textures inside Substance painter.

I have two objects (let us assume both have some asymmetry in it):

Image: https://us.v-cdn.net/5021068/uploads/editor/om/adhc4ok6o5ow.png

is it better to preserve a "better orientation" like this

Image: https://us.v-cdn.net/5021068/uploads/editor/h5/xu55k7tc833w.png

or is it better to save space like that

Image: https://us.v-cdn.net/5021068/uploads/editor/g4/d95hypwv7f96.png

remember: "cut" both in halve and also rotate to a better orientation is not possible of asymmetry

Noren · Nov 2018

If you are planning to do any editing in a 2D editor, a natural orientation will save you a lot of headaches. Is there a reason you left that undergarment with the sleeves in one piece, though? You could chop off the arms and have both, good orientation and use of space. (Not sure from what culture this is, but that often is were the actual seams are anyway, plus, they are covered by the overgarment. You can also consider slightly deforming the UVs so you can easily apply fabric texture overlays.

thomasp · Nov 2018

both are bad.

always keep at least a few pixels of distance between uv shells and don't rotate them at odd angles. any straight lines on the pattern will pixelate and especially display badly at lower resolutions (mip maps, texture filtering).

most importantly: as soon as you need to edit that texture outside a 3D painter it becomes really handy to not having to deal with that sort of mess. better to scale a pattern non-uniformly to fill up empty space. usually you don't need perfect aspect to get things to look right.

in your case the easy solution would be to look into turning this into a 2x1 aspect texture (2048x1024 or the like).

Alex_J · Nov 2018

With garments like this, something you may also need to consider pretty often is how you are going to apply a pattern -- like embroidery or whatever. Much easier if you keep things aligned in parallel/perpendicular lines. If you are working with Marvelous Designer, check this out : https://lesterbanks.com/2016/11/marvelous-designer-uvs-maya/

There is even some scripts out there that automate the process, though I haven't tried them.

If you aren't using MD, you may still want to look at the process just to see what the "perfect" UV's are. Of course it is situational, and you'll learn the best answer to your specific situation by going ahead and experimenting with the different approaches.

Here is some current work I am doing where I am asking the same question to myself (it's in progress, don't judge the mess). So I have this saree that, although being wrapped around the body and pleated in places, it's nothing but a big rectangle. So, ideally, I keep my UV's that big rectangle, then applying intricate patterns to it will be a cinch. I could just copy real life saree patterns directly. That would be ideal. However, will distortion make that impossible? Maybe I can just use a really big texture, or maybe even several, so the distortion isn't too bad? Maybe I'll just have to cut it up into random chunks and just do my best with 3d painting. Who knows, can't really answer until I try.

Image: https://i.gyazo.com/f7a3f78af3ceef122956c494bbb28106.png

goekbenjamin · Nov 2018

thanks to all.
i guess maybe my core question is: what benefits do i have if i rotate it?

Neox · Nov 2018

theoretically more texturespace. practically this is void with certain patterns as straightened uvs at 90° angles have less visible pixelation at lower texeldensity. curved uvs also tend to get lodded a lot worse that straightened edges. the small amount of stretching you get barely becomes a problem anymore with enough geometry to balnce it and 3d projection/bsking to handle it.

UVs: Orientation VS Spacing

Replies