Hard edges show in the normal map baked of a model in Zbrush 4R6 despite applying smoothing groups
polycounter lvl 6
Hi friends,I have an issue with my 3D asset here. Let me explain what I did before I faced the issue....
1. I made a 3D asset (A stylized axe in 3Ds Max with 872 quads)
2. Then I did the smoothing groups and the unwrap for all the sub objects of the model before taking the object in Zbrush.
3. I installed a plugin called smoothing groups plugin in ZBrush so that the smoothing groups which I made in 3Ds Max can be imported in Zbrush with the model.
4. I split the object into sub parts like the way they were categorized in 3Ds Max.
5. I did the polypaint and sculpting by increasing the divisions.
6. Now when I generated the normal maps and texture maps, I noticed that the normal maps have also baked the hard edges which were showing softened in 3Ds Max by smooting groups. The texture maps generated from the polypaint are fine though.
When I checked the low poly sub tools of the axe in Zbrush after bringing it to the lowest subdivisions, I noticed that the all the subobjects have hard edges along the mesh flow of the model, around almost each polygon, even where the mesh was with the same smoothing groups to be smooth. However those edges which were supposed to be smooth by the smoothing groups, after subdivision of the model in Zbrush become smooth again. This explains why I got faceted baked normals. I tried Xnormals but the maps are not coming out properly, even when I set the cage properly and covered both the high and low poly meshes properly with it.
I don't understand why the imported objects in Zbrush, before subdivision, show hard edges all along the places where the mesh was supposed to be smooth, especially when I had imported the smoothing groups. The mesh was in fact imported with smoothing groups because I can also see the creases (because of the smoothing groups) on the imported low poly model of the axe in Zbrush from 3Ds Max when I turn on 'Draw poly frame' in Zbrush. I rechecked the smoothing groups on the model in 3Ds Max and everything is fine.
I just need the normals to come out the way the model shows as sculpted in Zbrush.
I have imported all the necessary files and screenshots (of one of the sub tools of the main model) as an example, for a better explanation of my problem....
Please help,
Thanks in advance!
Replies
• First off, Zbrush does not support nor display face normals per say. Meaning that the SG import plugin is converting them to something that Zbrush can handle internally (I haven't used it recently, but that's probably either split polygroups of Zbrush "creases").
"Now when I generated the normal maps and texture maps [...]"
• Question is, how did you generate them in the first place ? The current reliable solutions are basically either Toolbag3, Xnormal or Substance Painter/Designer. Don't bake normals in Zbrush.
At the end of the day the problem you are having likely comes from a collusion between the Zbrush terminology and features, and the baking process itself. Focus on getting a clean high and a clean low out your sculpting and modeling programs (in obj or fbx), and practice baking one to the other in an app like Toolbag3. This will give you a better understanding of what's going on, and will remove all Zbrush related issues out of an equation where they don't belong.
Good luck.
Thanks for replying.
The issue I am facing is having faceted edges on the model imported from 3Ds Max in Zbrush, even when I have done the smoothing groups in 3Ds Max using the smoothing groups import plugin from Zbrush's plugins. Because of that when Zbrush creates the normal maps after going back to the lowest subdivision mode it also bakes the hard edges on the lowest subdivision mode (ones which were supposed to be smooth because of the applied smoothing groups). Apart from that, the normal map was fine. Even the polypaint was baked properly as texture maps.
I am sorry that I wrote my main post in a descriptive but complicated manner.
Apart from that, the normal map was fine [...]
What does that mean ? "Fine" as in, displaying perfectly accurately when shown in your final target environment ... which is ?
In short :
- If you are attempting to bake for games,
- then, Zbrush is irrelevant to the baking process
- therefore, what Zbrush does or doesn't do to your low is irrelevant, since your final low never needs to be imported in Zbrush anyways.
To make your post more clear you need to explain your context more clearly (target engine/renderer, and so on). If not you will very likely end up tackling the problem the wrong way around.
http://xyproblem.info/