RIGHT "flow and behavior" of UV's

Kkyc

Good time, comrades! I'm on way to create 3d character and now i'm on phase, where i must create UV map for my subject.
So, cause i'm self-taught, I watched and read a lot of information about IT, but i have couple of questions:

- What about "flow" of UV? (I haven't seen much material on the subject) 
On this image you guys, can see, that my lines are not straight AND i'm worry about it. How the straightness of the lines can affect to my work?

- Second question follows on from the first one. When i start to straight my lines, i face with some "weird looking" artifacts. You can see it in Image below:
Should i worry about it too and how i can solve this "weird looking"

AND i attach this photo (bellow), for compare "flow" of UV
(you can see here, the "flow" of UV and lines are so smooth)

rexo12

The checker (pun) grid will show you what your textures will look like with that UV mapping. If you believe that degree of warping on the test grid is unacceptable then change the UVs. I probably would consider that unacceptable - particularly the inconsistent scaling - but it depends on whether that area is really visible, and whether fixing it would sacrifice quality elsewhere that's more important. The straightness of topology in the UV layout itself is only really important for packing efficiency, generally more rectangular islands pack better, but prioritise how the unwrap actually looks on your model first.

Solving it is usually a matter of adding extra seams to create new islands with a more conformal projection. There is a minimise stretch function in blender but I've never found it particularly useful.

Klunk

wouldn't worry about it too much, keep them "neat and tidy" and easy to understand (for the next guy) and of relative equal density. It can have an effect if you are going for hand painted textures but even then some distortion is, to paraphrase agent smith, ineviatable but usually manageable. Otherwise with rrt as above it's all about effieciency and good organization the tools deal with irregularities and distortions.

dimwalker

Flow might matter for specific shader or if you plan to make a running light using UV animation, for example.
Normally you should not worry about it.

Neox

dimwalker said:

Flow might matter for specific shader or if you plan to make a running light using UV animation, for example.
Normally you should not worry about it.

it might be used for tiling detailmaps, then it will make a difference how you orbit your shells

Kkyc

@rexo12 thank you for your opinion and your pieces of advice! But as for scaling, I realize that if I do a whole character it won't make much sense, but in my case it's only a leg from the whole character