UV mapping techniques

Alec3d

I've read about a collection of techniques and was wondering what you guys use more:

1. relying mainly on automatic unwrapping by strategically using seams
2. use projection unwrapping and welding UV's together
3. using a program such as Unwrella

I'm keen to hear your thoughts!

throttlekitty

1,2 and hand tweaking for me. Kind of depends on the shape I'm mapping

3Drobbo

What i tend to so is lots of selecting parts of my model, planar map, and relax. Tweeking here and there to get it as best as i can.

RELAX its my best friend when unwrapping.

I tend to pelt map a lot of round surfaces, or curved surfaces. but other than that like above, planar stitch, relax, tweak.

I haven't used any unwrapping programs lately, but they never really worked as well as i wanted from my experience.

OBlastradiusO

There's a automatic unwrap technique I use in 3d Max. What I do is take a box or cylinder. Open the uvw unwrap editor. Go into edge mode, then make breaks in the edges to create opening seams. Then go into face mode after the seams are established, and select the whole mesh. Then go into relax mode and select "Relax By Edge Angles" and scale the iterations as high as you want. The mesh should unwrap and twist around automatically. Finally to flatten out the mesh hit "Relax By Face Angles" and mess around with the iterations again. Volia! Your mesh has unwrapped automatically. Hopefully I was clear in explaining this technique. This technique works for me like a charm most of the time.

Mark Dygert

It depends entirely on the object as to the best way to unwrap it quickly and efficiently. Sometimes I'll use automatic unwrap and stitch. Sometimes I select a few edges and break then relax, sometimes I'll use pelt. Often with splines and other simple objects I'll leave it alone.

I normally sort them into disorganized groups often with just a planar map on the group, making the pieces easy to select by element. Then I unwrap each group and arrange it.

I normally have a pretty good idea of how an object will unwrap before I get down to actually unwrapping it, that in large defines the groups. The type of material also plays into it and if I'm working with another artist or not.

Sometimes I assign material ID's before unwrapping just to make the groups easier to select.

Joshua Stubbles

I only use automatic unwrap for lightmap UVs, where everything needs unique UV space. Even then, I'll tweak those to get better usage.

The only other "assist" I use for hard surface UV's is an old maxscript called UV Paint. It's got real limitations though, such as having to convert to editable mesh, then breaking the UV's, before it will work. Once done, I convert back to epoly and weld UVs.
But it's really handy. It lets you literally paint UVs from one poly to the next and it keeps the texel distribution across each poly as you paint. After I use it I'll usually clean it up quite a bit by hand, but it's an awesome starting point for difficult shapes.

Bal

I use automatic UV unwrapping all the time (xrayunwrap/roadkill mostly), be it for characters or even simple objects. The results are fairly close to what I was getting when doing it be hand with planars before, and it's much quicker.
I still pack by hand in the end though, and tweak stuff around quite a bit.

kary

I use UVlayout at work and it's new auto unwrapping is fairly brilliant. If you do it piece by piece it keeps the UV islands sensibly placed together -- instead of all over the place like the other autounwrap/packs I've used. http://www.headus.com/au/doc/uvlayout-expert/videos/UVLayout-Segment.mov

DEElekgolo

I usually use pelt map, or just unfold 3d. And if that doesn't work out nicely then I do everything in headus.

renderhjs

like many others I used to mark seams and then flatten (relax) shells but I found it to be much much faster by simply selecting faces (e.g by normal angle) and then flatten it as a shell like this:

I binded the "Planar" button from the unwrap UVW interface combined with a relax iteration on a shortcut. The same can be found in this command:
from textTools

A similar workflow I use with this script:
http://www.renderhjs.net/textools/texTools_internet_images/texTools_1.9_pelt_mapping_preview.gif
(not yet included in TexTools) where I can edge loop select edges and unwrap the associated faces of the edges with a single shortcut.

I only use automatic unwrapping for exploding my UV for the first time so its easier to sort out what belongs together.

Alec3d

thanks for all your comments guys, seems to me that most of you guys are using max and maya - I'm fairly familiar with the maya interface but It's too expensive for a youngen such as myself so I'm currently going to buy Silo for most of my modeling and UV work and so far It's really a step forward for my workflow.

Mongrelman

I use blender myself, and tend to do 1 and 2.

Sometimes I do a planar projection of an area to make sure those uvs are exactly the way I want, pin them and then do the pelt mapping so the rest of the uvs move around this area. Then pin some uvs and move them about to adjust the rest of the map.

Often, mainly for mechanical type things, I'll go over most of it and align uvs manually to help with texturing.

Zwebbie

I use Blender and just do #1. Sometimes it's useful to do something like Mongrelman, where I don't want bevels interfering with the unwrap, but that can be done by selecting the basic faces and doing the usual LSCM on them. Blender has two unwrapping methods, conformal and angle based. One's supposed to be better at the organic and the other better at mechanical, but I always just use the default until something doesn't turn out well enough and the other method will yield the right results. For faces, I tend to pick a few anchor point vertices to pin and then move them around to distort the map into giving more space to the face and the nose especially.

Alec3d

I agree, for most of my characters (I'm fairly hopeless at modeling believable weapons) i just place seams here and there and use LSCM, then I go in with a few manual tweaks in live UV mode. For weapons that I've texture I think that of course it's faster to try and place seams everywhere it is ****ing annoying to do and the results are very meh where as using planar mapping gives you precise control.

eld

LSCM in blender, pack them together, done.


no stretching, unison pixel density.

Alec3d

got any example pics?

vargatom

LSCM is exactly the opposite of no stretch and uniform pixel size... You can't just wrap anything into a square without that...

Mark Dygert

MoP has a great MaxScript that normalizes the size of your UV islands so pixel density matches. Renderhjs rolled it into his TexTools also.

Relax does a good job in Maya or Max of minimizing stretching. I would be highly suspect of any tool that says it can eliminate stretching.

t4paN

Roadkill stand-alone works very well for organic models, other than that, break and relax.

Ghostscape

I do mostly hard surface stuff, so I tend to run a flatten map on the whole thing, move that out of my 0-1, and then use a combination of stitch, relax, re-flattening (I use the hell out of renderhj's iron tool), and pelt mapping.

And of course there are the occassional cylindrical/spherical projections - those are rare but useful, although if you have simple cylinders (X sides+single poly top) running the unfold mapping on it gives you a better, quicker unwrap than a cylindrical projection.

Tumerboy

I can eliminate stretching Vig, I just split EVERY edge, and flatten each poly individualy.

eld

vargatom wrote: »

LSCM is exactly the opposite of no stretch and uniform pixel size... You can't just wrap anything into a square without that...

the very definition of lscm means that it will try to unwrap a group of polygons with the least amount of stretching, no unwrapping can defy the laws of surfaces.

you point out splits, it does the rest.

Mark Dygert

Tumerboy wrote: »

I can eliminate stretching Vig, I just split EVERY edge, and flatten each poly individually.

Heh, touche' =P