Anyone know whats going on with this? ive seen this happen in maya too.
What’s happening is that you’re using a tangent-space map. The math behind this type of map flips the normals whenever you cross a UV seam. This is not a ZBrush issue; it’s inherent in the map type.
You can remap your model to hide the seams as much as possible. Or you could use an object-space map, which has different math behind it. Or you could try the technique here: http://www.zbrushcentral.com/zbc/showthread.php?t=56882
hey aurick, i’m trying object spaced normal map now. i have a quesiton (not sure if you’ll know or not) whenever we’ve done normal maps at work, or when i see peoples screen grabs its always the tangent space normal maps. is there like a rule of thumb on when to use which type of map? hope that makes sense.
Hi Nerver Met A German,
The saying is that Object space normal maps can’t be used for objects
that are gonna deform or get animated.
I don’t know why, but it is what is said by pros everywhre.
It’s a kind of normal map that I think can be used on static
props I guess.
As for your details getting flipped.
Here is my solution for my Zmapper tangent space normal maps.
I’m using 3ds max R9 and I’m using 3dsmax8modifiedE zmapper config file.
Maybe it will work for you.
In the expert pass 1 tab turn on derive normal from tanget x binormal.
You have now to make 2 renders of your Tangent space normal map.
In the Normal and Cavity tab:
-Flip red/green on the first one
-Just flip green for the other .(meaning just flip back red to it’s original state)
Mix both in Photoshop
(do not blend them,just cut and paste)
Tell me if it worked.
hey christian, when you say cut and paste what do you mean? if i cut and paste in photoshop, i have 2 layers and i’m unable to see the layer underneath. i’m not sure what you mean exactly. i’m trying to post some test renders online so i can start rigging but i cant until this normal map thing is fixed. oy…
Basically ,you are just pasting a chunk from a normal map to another .
You don’t need to see what is under ,you are replacing it.
ex:
I have a seam between two Uv parts and the details are inverted
on each side of the seam.
What I do is I just make 2 renders of the normal map
using the 2 different zmapper settings I told you.
Then,I open them both in Photoshop,
I use the polygonal lasso to select around the seam of NormalMap#1
and cut/paste it over NormalMap#2
Again,I’m using Max R9 and the 3dsmax8modifiedE Zmapper config file,
so the 2 settings combination might not work if you’re using maya or even another max version.