I am working on a model that I take frequently between 3dsm and Zbrush. Pictures at bottom.
My workflow is as follows:
Create low poly base mesh in 3dsm.
Using smoothing groups and turbosmoothing I subdivide the whole model without losing the overall shape by using smoothing groups.
Take the turbosmoothed model into Zbrush where I can subdivide even further without losing the form/shape. If I would take the low poly mesh into Zbrush and subdivide it there I would get very bad results since I couldn’t keep the shape like I can with smoothing groups. Technically I could do it with extra geometry, but that is something I’m avoiding.
Sculpt details in Zbrush and bake out normals and apply to the low poly in 3dsm.
This method has worked pretty well except for a minor issue. Basically, when I apply Turbosmooth, the seams of some of my UV islands get distorted. Those distorted UVS then get taken into Zbrush and baked onto. So when I apply the normal map to my low poly, the distortions are very obvious since the UVS of the low poly have not been distorted by Turbosmooth.
Here you can see the subdivided UV map on the left gets curved edges while the unsubdivided has straight edges.
Here you can see the distortion inside the red circles.
I did google the issue and found multiple threads about it, including ones from cgtalk like this however none of the solutions listed there work. Except the one about adding more geometry but that I’d prefer not to do, same with adding a UV unwrap modifier on TOP of the Turbosmooth because then I could not use my normal maps on my low poly model.
I did try splitting all edges, copying the Channel info, and pasting after disabling the edit poly where the splitting occured. No luck.
Most of the threads I found are at least 1-2 years old so I was wondering if there are some common workarounds for this issue?
edit: Ofcourse I “found” a way to fix the issue somewhat a few minutes after posting this thread. Detaching the affected polygons to element seems to minimize the problem. Although it has not completely disappeared.
However I’m not sure if that might cause other issues along the way, for example when I’ve taken it to Zbrush and start doing normal bakes since now many parts of the object are seperate geometry.
I’m still interested in hearing more solutions to this or if I’m doing something terribly wrong. Also some others might be having similar issues and this might be helpful.