I was looking at 3d-io’s Unwrella and UV-Packer and I’m trying to understand why someone would want all the UV’s to have accurate proportionate scaling? Is it better to have it accurate, rather than have the UV’s for the head and/or hands larger to have more texture space for added detail? Is there drawbacks for having UV’s different sizes when designing for a game engine?
What about where to have seams on a character model? I’ve seen meshes where each of the body parts have their own unique UVs (each leg, earch arm, torso, head, etc.) Then I’ve also seen a pelt of the entire character with all the body parts as one continuous UV (Poser style). Is there a drawback to one over the other?
It all depends of what you want to achieve. Separated UVs could come in handy when you want to switch complete parts of the character while runtime. Where you dont need it you may be satisfied with just one texture per mesh. Depends of your needed resolution. Sometimes you may have to split a texture because one texture would not give enough detail.
Accurate proportionate scaling is important to prevent odd looking differences between the textures. It is very visible when you come closer to the object. When there is different scaling, then the one material already shows blurring from resizing the pixels while the other material may still show a detailled and sharp texture. On the other hand, at hands you may need more detail. Also here, it depends.
Setting seams is a thing of experience. Have a look how pros are setting their seams can help. But is no guarantee that you can adopt it to your current mesh one to one.
I have checked Unwrella and it doesnt look that good. I would strongly suggest you 3d coat. It has excellent UV tools, i use it all the time, and it is the same price as Unwrella, plus you get all-in package with retopo, sculpting and what not. However just one thing to note, you will still need 3ds max or maya probably if you want to repack UVs better or if you want to do some changes to UVs.
Unwraping whole character is never a Pro solution. Never. This is only fast way to do it, but you will lose a tons of UV space, thats why all pros unwrap every part of character in different UV tile to save space. I would suggest you not to get used with whole pelt maping of object on any object, it is always better to break it and save some space. The only good side of pelting whole character or mesh is that you have low number of seams, but that doesnt justify it for games, maybe it does for movies where you can use huge textures.
Have to disagree. You can also waste lots of with separated UVs at several textures. Because this separate textures all have a border, which you cant use then. But as told, it always depends of what you want to achieve. And every artist most probably has another opinion and workflow when it comes to unwrapping
Thanks. I’m just trying to get some thoughts for the best way to UV my character mesh for a character creator and first person shooter in the works. I have the base mesh completed and I was looking for advice as to how UV and texture it. If I wanted the player the ability to add cybernetics; such as legs and/or arms that are similar in streamlined shape to the flesh counterpart, should I use one texture sheet and swap them out depending in what they add, or should I have the arms and legs as separate meshes/textures?
Tiles, you mentioned that different UV sized become very visible when you get close to the model such as with a character creator. I probably should have the head as a separate texture, but still have the character mesh as one model. Not sure how noticeable a 1024 texture for the head and another for the entire body would blend…
Unwrella is not for the painting phase at all. What you use unwrella for is baking. So, you’ve either unwrapped the model first by hand, using different proportions or whatever, then when you want to bake out high quality normal maps and get more efficient projections, thats what unwrella is good for.
The reason you might want to adjust the proportions of certain areas on your model can vary a lot, but a common thing with a human model for instance, is to focus on the areas you want/should have more detail, like the face (often unwrapped on a seperate UV layer) at the end of the texturing process, a plugin like unwrella optimizes the uv space for you so you can get the highest efficiency transfer/bake etc of the maps onto 1 uv space to save resources.
This good old method will not work well for organic shapes. Too much seams that way. And too much unnecessary work too. Marking seams, then apply LSCM is more efficient and better looking in most cases. Needs a bit trainig though until you are comfortable with how to cut your mesh in the best manner.
Hm, from what i can read Unwrella is for automatic unwrapping, not baking.
We have FlatIron here, which is the big brother to Unwrella (not available for Maya though), and we use it a lot on a daily basis.
For clarity, Unwrella unwraps single objects; FlatIron extends this by unwraping many objects into a single (or multiple) UV set - not dissimilar to how Beast works. However the unwrap quality and packing is far superior to beast.
Proportional scaling avoids texture stretch, and ensures the pixel detail on your models is consistent and without distortion artifacts.
FlatIron (and I’m pretty sure Unwrella too) has options for retaining Seams (with a threshold value) for flexibility. As a fast wrapping/baking solution it’s indisposable for the pricetag.
The key thing with Unwrella is that it lets you have extremely effecient UVs here and now, and when you’re working with Work In Progress models it’s a no-brainer - worry about custom UVs when you’re ready to spend time on them, but even then you’ll probably find the Unwrella UVs are more than good enough.
All of this said, if you’re working on shared dependencies between characters; interchangable body props, textures sets and common UV layouts, then automated systems probably aren’t the best way to go.
This is correct. Our own everyday usage is to use it (or FlatIron, same process) to create a second UV set and bake textures from UV0 (quick and dirty in-progress mapping) onto UV1, then when happy with the result copy UV1 into UV0. It’s very flexible, and of course because they’re just regular UVs you can edit the layout to suit your needs afterwards - a side effect of the packing efficiency is that with a complex object (or in FlatIron’s case, lots of objects), not all UVs are guaranteed to be aligned with the vertical/horizontal plane (i.e. it will rotate UVs if it means tighter packing is possible).
Note however that there are two packing modes - organic and hard surface - and they both give very different results; the target mesh type should be self explanatory.
I should clarify what I ment by baking. What it does is help you create an efficient final texture layout for baking purposes. IE transfering high res details from a high res painted model onto a low res version. It doesn’t generally create nice uv’s for painting on, at least not for anything hard surface wise, it does a decent job creating organic uv’s - if you lay the seams out and use some tricks to get holes to look correct. Unfortunately for me, it always created to much stretching to be helpful with anything hard surface, and I found manually doing those was faster. Especially in max 2012 with some of the tool changes, combine that with textools and you can unwrap really fast and efficiently.
I would suggest you to break character into two parts. One is head and second is body. If you mean to do this character for character modification then this is a must. Changing whole 1024x1024 texture just to change players head is useless and very heavy on resources. So if you load only 512x512 different texture it is more sparingly, especially if your game has several characters in game at once.
If you want deeper modification scene you might also want to separate eyes and hands, but that depends what are your resource budgets for game.
Thanks everyone. I think I’ll experiment with two textures; one for the head and one for the body and see what kind of “seam” I’ll notice between the two textures at the neck.
Photoshop CS5 and beyond has a default unwrap with minimal stretching options, then import to your favorite UV editor to move and stitch together. The 3D painting tools in PS are very nice. I haven’t worked with any complex objects though. I am still looking for an easier solution, UV mapping seems to be a huge pain, although I hear zbrush has some sort of magic button that does awesome unwraps for you, but that’s not a very cheap solution.
