Normal map help please

tehrobster2

So I tried maya transfer maps and Xnormal, and I am getting this weird thing with my normal maps. And I was hoping some one would be able to help figure out what I am doing wrong.

r_fletch_r

its impossible to see whats wrong with this. post a viewport image of whats not working.

Stromberg90

mm, you have to post a screenshot of the model with the normal map on.

We cant really tell whats wrong unless you do that, remember if it looks right on the model it is right

tehrobster2

high poly and low poly with normal map

Mark Dygert

I'm going to take a guess and say its something like the green channel needing to be inverted... I think the xNormal default is the same as UDK which is the same as 3dsmax, and in order for it to work in Maya the green channel has to be flipped?

But that's a wild stab in the dark. I don't bake all that much with xNormal and even less with maya.

leechdemon

Mark Dygert wrote: »

I'm going to take a guess and say its something like the green channel needing to be inverted... I think the xNormal default is the same as UDK which is the same as 3dsmax, and in order for it to work in Maya the green channel has to be flipped?

I believe Green is flipped in xNormal by default; I have to invert Y in max to get my maps to come up correctly.

Yeah, this does look like something that can be caused by that, though. The result is fairly smooth, but "wrong". Anytime where things tend to look wrong on edge lines, it's because the normal map is working, but pointing in the wrong direction. Either a tangent issue or channel inversion.

tehrobster2

So does anyone have any idea how to flip the channel in Maya??? and thanks again guys!!

Thor Sowards

You should prob flip it in photoshop. Just go to the green channel and flip it

cryrid

You could just flip the channel on the texture itself using photoshop or a similar application. Or rebake in xnormal and change the Y setting.

tehrobster2

Sorry for the newb questions, but in photoshop by flip do you mean invert the green channel, and where in Xnormal, do I change the Y setting.

cryrid

Yup, invert for photoshop. For xnormal, it's in the baking options for the normal map ("..."). You can change the X/Y/Z's +/- values.

Giometric

You don't need to invert the Y channel for Maya, XNormal's default swizzling of +X, +Y, and +Z should work fine. It doesn't really look like an inverted channel problem anyway; larger screenshots would help us to see it better, but from what I can see there it just looks like the edges are all screwy. It's possible you just need to smooth all the normals on your low-poly object (select object, go Normals > Soften Edge).

tehrobster2

yeah I softend the edges, could it have anything to do with the uvs?

Giometric

The UVs can cause trouble with baking if there's any overlaps in them or if the spaces are too small, etc. That doesn't look like the case here, but if you do have any overlaps make sure to get rid of them and try baking again (you can also move the overlapped shells 1 unit away in U or V). On the soft edge thing, try baking the normal map again with the low poly already having all the edges soft. Also, are you making sure to switch the bump map type to Tangent Space Normals in the material's bump node?

I_R_Hopo

Can you post a screen shot of your low poly without any normal map? It might be a smoothing group issue (Those harsh lighting triangles often happen when you haven't set up your hard edges properly).

tehrobster2

Here ya go, and thank you Giometric, you was right i needed to change from bump to tagent space, and still have a few errors but still working on it, might just have to fix some of them in Photoshop

I_R_Hopo

It's kind of hard to see, but it definitely looks like you didn't set up your smoothing groups properly. Remember that any 90 degree or sharp corners should be hard edges. If you do this and still get some shading issues, screw around with the smoothing groups to get a workable result. Any harsh shading issues on your low will remain after baking. Also remember to split your UV islands wherever you have a hard edge or else you'll get black lines (But having one island containing multiple smoothing groups is okay I think. I've never run into problems doing that).

tehrobster2

So your saying that the spike should have hard edges ???

I_R_Hopo

I don't think the spike would need hard edges... It's shading looks decent from what I'm seeing there. Anywhere you have those sharp angles though, they should be separated into different groups. (I don't mean sharp as in the spike's point sharp, I mean sharp like perpendicular lines)

nullfed

*i need to learn to read*

tehrobster2

Thanks for the help everyone, I have been reading more and more on proper normal map making, and thanks to you guys help, I keep learning new steps.