Xnormal - normal map seams, inverted??

Illusive

Hi So it's been ages since i've played with xnormal or normal map at all but i was doin a test on a wheel and i'm not sure what's gone wrong, it looks like part of the uvs are flipped or something, has anyone seen this before or know what i'm doing wrong?

thanks in advance

Illusive

k so i figured it out (if anyone cares)

took it off tangent space and made it world instead seemed to give me good results

Butthair

Glad you've figured it out, but...

What does it look like as a world based normal? What does your hi poly model look like? If the surface of the tire which meets the ground is a curved surface, but the low poly is flat, you will get a gradient like that which compensates for that curve.

The match up for the long strip and the tire side surfaces also don't match up in normal color, which might be caused by smoothing groups or a lack of edge angle support, meaning it's a 90 degree angle on your lo poly, where you hi poly might have a prominent curve on it.

Illusive

thanks butthair, the tread around the high poly was flat but you were dead on about the smoothing groups.

turns out world/object normal won't work in the engine anyway so i'm back to using tangents. being a noob i had a lot to work out. the main difference i found between the two normal map types are to do with smoothing groups and putting seams on all hard edges. also worked out that i needed the Y inverted.

i still think object/world normal look way better but reading up on them they're pretty limited. getting much better results now though.

Ace-Angel

Don't put your normal in your diffuse to look at them, that's a terrible way to debug stuff.

Instead put in your Normal slot and see if it looks good, it not, fix you Smoothing, Chamfer edges, etc.

metalliandy

Ace-Angel wrote: »

Don't put your normal in your diffuse to look at them, that's a terrible way to debug stuff.

Instead put in your Normal slot and see if it looks good, it not, fix you Smoothing, Chamfer edges, etc.

This.

It's perfectly normal to have normal map look crappy when it's displayed as a diffuse texture, so don't worry if it looks like there is a seam when you apply it as a diffuse map

When the edges of your mesh are rotated in UV space, there will always different colours at those edges. This is because they are at different angles and the tangent basis uses these colours to correctly light the mesh.

If there is a seam once the normal map is applied correctly, then you can worry