Normals, UV's and Round Edges

Klaus Hustle

Hi, i was lookin for some help on google for one issue i have since i started learning UVs 3 weeks ago (yeah i am pretty much beginner level).

i get so frustrated in getting a decent normal-map on my lowpoly as i get visual errors all the time.

i am using 3dsMax and xNormals btw!

So i tried it with a simple box first and succeeded after alot of experimenting. I got rid of creepy edges with arranging my UVs in islands rather in having it unfold along the seams. Sorry, please correct me if i confuse some terminology here.

But when im doing something more advance than a box i get into the same troubles i was when i used my unfold Box UV's

So here are some Screenshots:

Here is the problem first, it's pretty obvious:




same view with edges activated:




The High-Poly-Version i created. I just made more Cuts and applied TurboSmooth on it.



and finally, here are my UV's



i know this kind of stuff is very complicated and you cant teach me everything i need to know about this stuff in just one posting here, but can you please give me some hints and buzzwords to look up so i have a higher chance of getting to know this stuff better?

I've read some stuff in the "You're making me hard." -Thread but i dont get it.. first of all i wanted to know what UV-Splits and Smoothing-Splits are? That would help alot to follow the Informations given in the thread i assume.

cheers!

demigodssw

did u try padding option during projection?

Klaus Hustle

i raised the padding in xnormal to 16 yeah, but it has no effect on islands that are stitched together

demigodssw

i am still not very experienced but i think smoothing and uv splits are applying different smoothing groups based on where u have split ur uv or spliting uvs based on ur smoothing group but maybe i am not entiirely sure about it 
and did u export ur objects normal while exporting? and did u use use exported  normal in xnormal?
and can u show us ur normal map plz

Klaus Hustle

i chose "use exported normals" in xNormals yeah!

here is the normal map...

looks pretty bad right... i couldnt recreate how it looked before i started to experiment with it...somehow some additional errors made its way into this map :C 

here is a render with the result 



the area i tagged annoys me the most, but overall its not really rounded

Scruples

It's the smoothing groups/hard edges causing the problems, they should only be separated on UV splits.

Klaus Hustle

u mean like that? i split the uvs on the side by angle, but it has no positive effect on my outcome. to be honest, i have no idea what i have to do with the smoothing groups... can you give ma hint or a good ressource on this stuff? i watched some stuff about it, but its either was too basic or too advanced.

Tzur_H

read the sticky threads about normal mapping in this sub forum...
also, normal maps have their limitation, if the shape of your low poly is drastically not matching the high poly shape, you can't really expect much. it's not a miraculous thing

Klaus Hustle

i know, but the 2 meshes are matching each other. so i worked through alot of info but still got crappy results. 

a bit unfortunate btw that so much attached pictures in the early pages of the stickys wont show anymore.

commador

You don't need to separate your islands that much. Keep it to around 90* or greater**. Search around for UV border scripts that will harden the edges along island borders. This ensures that smoothing groups are applied to each chunk as they are needed.

**As a general rule of thumb. This can change depending on target engine and any specific pipeline requirements.

Deadly Nightshade

Are you using a cage in xNormal? In Maya you can easily create one by selecting the lowpoly and then going into the Render tab > Transfer Maps > Load the mesh at the top. Then in the drop-down menu for "Envelope" select "Both". Now give it a low value like 0,1 and select the envelope mesh in the Outliner and export it.

You can probably create one by local scaling the faces as well (under modelling toolkit) but I like the Transfer Maps trick as it always gives me good cages.

Klaus Hustle

commador said:

You don't need to separate your islands that much. Keep it to around 90* or greater**. Search around for UV border scripts that will harden the edges along island borders. This ensures that smoothing groups are applied to each chunk as they are needed.

**As a general rule of thumb. This can change depending on target engine and any specific pipeline requirements.

ok, thanks for the hint! i lack a lot of experience with UV's etc.. so that helps. First i thought its more important to stitch everything together, i also see this is still very common...but dont seems to work well with normals  

So the Script that you mentioned will do basically smoothing groups out of my island?? i made it by hand now, and it worked very well, posting results below. such script would be handy.



these are the best results i ever had lol.

i tried it with 3DSMAX only this time, instead of using xNormal. Not that i think xNormal is bad or something, but i felt like trying a cage like recommended but 3DSMAX gave me a little bit more overview of what im doing with the Cage etc. I will still try with xNormals.

Deadly Nightshade said:

Are you using a cage in xNormal? [...]

thanks for the hint with the cage! i am using 3DSMAX, but there is also an easy way to do this in max ofc!

i really appreciate your help.

i hope it will still work so good with my initial object, still have to try, much fear ;>

by the way, i noticed alot of tripping hazards on the way, man...

Tzur_H

yes there is a script that can set up your SGs based on your UV layout (and much more), for 3ds max the script is called textools - look it up