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Pro artists tackle your queries

- Cirstyn Bech-yagher replies

So, if mirroring and overlappin­g parts of the model’s UVS means you can get the resolution you need from a smaller texture, that is more efficient, right?

Questions about unwrapping humans have been around since planar mapping was a thing. The most common questions are about dividing the model, cutting and unwrapping hands, faces, lips, eyes and nostrils. Feet, not so much.

As always, the unwrap depends on your model’s destinatio­n. A good rule of thumb to remember is that if your personal sculpt isn’t going any further than a render engine, you can cut it up and unwrap it as it suits you. If it’s for VFX or a game engine, you need to consider a few more things; despite some of the big studios using one flavour or other of Ptex in their pipeline, UDIMS still seem to be the norm, and as such, they pretty much follow guidelines for good UV layouts, like good space utilisatio­n, as flat as possible, and being easy to read and work with.

As game engines still don’t have (proper) UDIM support, you need to make the most out of layering on your single UV tile. In itself, a human body won’t need much stacking, other than i.e. hair or body hair, eyebrows and eyelashes. And while game engines currently can handle an insane number of geometries, you still need to take clothing, interchang­eable

parts and their shaders into considerat­ion when unwrapping.

A workflow I took with me from project management into 3D and freelancin­g is to always start with the most work-intensive or challengin­g tasks if you can, as they require the biggest focus and effort. Once the heavy lifting is done, the lightweigh­t tasks often don’t require as much effort, and it’s always easier to get help for those if needed.

So, when I unwrap a human, I often start with the face or hands. I take a look at where I can hide distortion (behind the eyeballs and under the hair, if I know it will have hair on a head) as well as the best places to cut in order to squarify the face, as a lot of game studios require unwraps as square as possible as part of utilising maximum UV space. I also look at the rest of the body, whether I can pelt or cut it with symmetry, as well as checking what tools to best use where, such as the magic wand, Topocopy and brushes. I consider where to put seams and how I can minimise cuts if that’s a requiremen­t, and how to work with my texel density budget.

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 ??  ?? Humans are generally no more difficult to unwrap than other objects
Humans are generally no more difficult to unwrap than other objects
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