Renzatic on 10/8/2019 at 21:51
Quote Posted by Nameless Voice
UV mapping and packing really ought to be something that a computer should be able to automatically at a single click so you'd never have to worry about it. Sadly, it's a kind of complex problem and no one has developed a really good algorithm for it yet.
I've heard that Cinema 4D and Maya are decent at UV packing. Blender? It gets the job done, but it's not exactly efficient about it.
Nameless Voice on 11/8/2019 at 02:06
That's a shame. I had a foolish hope that if/when I finally get around to learning Blender, it would do a better job at UV mapping and packing. Guess I'm going to be disappointed.
Renzatic on 11/8/2019 at 03:34
If you want something really nice, and are willing to spend about $170 USD for a program that just UVs, I've heard a lot of good stuff about RizomUV Virtual Spaces.
[video=youtube;z2QvajdFHes]https://www.youtube.com/watch?v=z2QvajdFHes[/video]
Judith on 11/8/2019 at 09:26
I'll send you the link when I get home, as I only have phone now. Btw. It's not true that proper UV division and placement gets irrelevant because of the Substance "magic". You still have to make some decisions here. Good thing is, most of the unwrapping tools have things like unpacking uvs according to smoothing groups, settings for padding etc.
Judith on 11/8/2019 at 18:02
The explanation starts around 5:30.
[video=youtube_share;ePnLTuzRAbg]https://youtu.be/ePnLTuzRAbg[/video]
Judith on 12/8/2019 at 07:29
Now that I'm at home, a few more things worth clarifying:
1) High poly vs smoothing groups vs uv islands:
Usually, your highpoly model shouldn't have any smoothing group (or just have one) and look correctly. > Your low poly model should have smoothing groups that would mimic the high poly look. > Its uv islands should match smoothing groups - you should have uv seams where the hard edges are.
Now, "hard edge" might be a bit misleading, since you'll often find that it doesn't always match the "real-life" hard edge. You'll get much more predictable results, when you assume that "hard edge" is when the angle between two surfaces is 80° or more.
2)
Quote:
It's weird how every tutorial I've read or watched on UV editing over the years has stressed keeping your UV unwraps as seamless as you possibly can without distorting the underlying geometry.
Hah, nope. Aligning UV seams to smoothing groups is one thing, but at least in case of normalmaps, it's better to keep angled UVs straightened. Not only they're easier to pack and save texture space, but you also avoid normalmap pixel aliasing, which might become a problem when scaling down your textures.
Renzatic on 14/8/2019 at 06:26
It's funny how I used to think UVing was this arcane process that could only be barely understood through years and years of practice. I've come to understand that UVing is actually quite easy to wrap your head around.
It's just tedious as fuck.
And speaking of Blender, and good UV packing, I came across this entirely by accident a little while ago, and thought of posting it here. It's a $20 addon, but it looks to do a decent job packing UVs. The only thing that Blender's still missing would be a UV relaxer, which I'd really love to have.
[video=youtube;-uunwDLWn7A]https://www.youtube.com/watch?v=-uunwDLWn7A[/video]
Judith on 14/8/2019 at 06:47
Quote:
It's just tedious as fuck.
It's like a penalty for having fun modeling cool stuff, basically.
But I prefer to do this semi-manually, because:
1) In case of materials like wood, you'll make your life easier if you position all the islands vertically or horizontally, so they're all properly aligned with the woodgrain.
2) If you have several surfaces per model, you'd want to group UVs per surface in 0-1 texture space (better readability and editing in Photoshop/Gimp later, Substance Painter isn't 100% self-sufficient for me)
3) Contrary to popular belief, not all surfaces of the model have to have equal pixel density; those less important, rarely visible, or visible from afar can have smaller uv islands, you just have to be careful with controlling that.
4) Mirrored UVs aka the biggest dilemma that you can have with UV islands. Great savings with texture space, but you have to watch for obvious repetitions and faces that can or can't be seen simultaneously when walking around the model.
All of these require your decisions.