blender uving a long group of polys

MainManiac

I'm not sure how to explain it, but basically I have a single row of polys(just an extruded plane) thats bordering a low poly catwalk (think upright handrail) that starts and stops and curves a bit.

In Max id just select the polys and then relax and get a straight row of polys in the UVs (or multiple rows since theres breaks in the mesh). But in blender when I unwrap the selected polys and hit relax nothing happens and I can't get them straight.

By straight row I mean

[][][][][][][][][][][][][]

But instead they have a shape similar to the shape in the actual geometry

I'm currently not home but ill be happy to provide pictures later if this is hard to visualize

Thanks!

xrg

The w-key has options for alignments, but afaik it only works on vertices and not entire faces, so would be pretty tedious with a lot of geometry.

In some cases, you can pretty good results by unwrapping using follow active quads or project from view.

MainManiac

Follow active quads looks really useful and I did not know about it, Thanks for that!

But heres an example:



In max I could just relax that in the uv window and get even pixel coverage, how can I do that in blender? It keeps coming out squished

MainManiac

(bump) I've tried googling but I don't know what this is called, and blenders relax acts different than max

This is stopping me from uving a model

In the viewport the model looks like above:
[-][-][-]

But when I unrwap it in blender it looks like:

[][][][][][] with uneven pixel coverage and the faces are all "squished"

And like I said in max I could just relax "[][][][][][]"
and it would slowly expand into [-][-][-]
And give me even pixel coverage in the uv space

frmdbl

Did you apply the scale?
(Ctrl + A, scale)

In Blender there isn't really a lot you can do with UVs after unwrapping
in terms of straightening or even relaxing compared to 3ds Max.

Michael Knubben

Now we're on this topic: is there actually a decent relax in Blender?
'minimise stretch' doesn't do much, and what it does is usually not what I want at all. You can smooth with the sculpt brush, but is there just a command to relax a selection?

frmdbl: far from it, the alignment (w) menu is quite nice for straightening stuff. I miss a few things from Max/Textools, but the unwrapping's really quite nice as long as you deselect 'keep uv and edit mide in sunc'.

MainManiac

frmdbl wrote: »

Did you apply the scale?
(Ctrl + A, scale)

In Blender there isn't really a lot you can do with UVs after unwrapping
in terms of straightening or even relaxing compared to 3ds Max.

The amount of pixels inside the faces is not proportional to the size of the faces on the real model, so scaling it fixes it a little but not really

frmdbl

@frell

I made a similar mesh, unwrapped it, applied a uv checker pattern and the pixel ratio is perfect.
I can't think of what you may have changed,
maybe if you post the .blend we can sort that out.

Now we're on this topic: is there actually a decent relax in Blender?

I think the two you mentioned are the only ones.
The thing about unwrapping in Blender is that it uses LSCM algorithm, so there should be very little distortion by default
(It doesn't work that well with hard surface though).

After unwrapping like I said there isn't really a lot you can do in the UV editor.
Even 'stitch' was added very lately, and up untill the latest release it was pretty much useless cause it stiched all the islands connected to the selected vertex,
(now it's edge based like in max)

The 'w' menu works only per vertex, so you can only straighten a selection of vertices. It's nothing compared to Max's straighten, which sort of gives faces right angles.

What I find extremely useful in B though is 'live unwrap' coupled with pinned vertices.

EDIT:
@frell

I don't know if you understood me properly. I don't mean to scale, but to apply the tranformations(scale in this case).
It's like reseting the Xform in Max.

xrg

I just tried to model a similar shape then u->unwrap. I don't get any stretching, but I'm not entirely certain that's what you're having an issue with either. I've never used 3ds Max, so I don't know it's UV workflow.

Frankie

It does the 'follow active quad' ratio based on the active quads uv so if you don't have that one allready uvd at 1:1 the rest wont be.

MainManiac

Weird, it seems the thinner the strip of polys the more distortion there is but im still having problems

This is the border of a ship, and the result is after cutting it at the stern and bow and unwrapping...



Sure I can just manually stretch that longer part but I don't understand why it isn't coming out even. If this was a more complex model id be shitting bricks

MainManiac

bump

Frankie

upload the mesh if you want more help

MainManiac

http://uppit.com/p5friiimfdmv/example.blend


Heres the area that would take me half a second to get even in Max but I cant get right in blender:

frmdbl

Change the unwrap 'method' from angle based to conformal,
this gives much better results to me.

Other than that, you can use more seams, or 'Smart UV Project" and then stitch the UVs.

Frankie

that is pretty wired yeah, I get the same issue just taking a plane scaling it down 0.01 and doing a unwrap, wrong aspect ratio and a skew.

The change frmdml suggests makes it a lot better though, strange I never noticed it before!

MainManiac

frmdbl wrote: »

Change the unwrap 'method' from angle based to conformal,
this gives much better results to me.

Other than that, you can use more seams, or 'Smart UV Project" and then stitch the UVs.

Where is that setting?


Thanks guys

Nosslak

I'd rotate it to be mostly straight by rotating the segments around the 2D cursor (dot-key is the hotkey for that) like the top segment on the picture, hit W->Align Auto, then hit P (or UVs->Pin, whatever you like) and unwrap it again. Lastly you'll still need to go over it all and aligning all the edges you want straight, but this'll give you minimal stretching.

EDIT: I forgot the picture:

frell wrote: »

Where is that setting?

It's under the 3D Views Toolbox (T-key) when you hit unwrap under Method.

MainManiac

Thanks guys, that seems to be exactly why I was looking for!