Best practice for Displacement tearing?

3D4Eva

I'm running into some issues where I have cubes, or even a sphere with a single uv shell (from zbrush) and if I do any displacement it will tear and split apart at the seams. I have no idea how to avoid this problem on a complex mesh where I need displacement in several spots.

Aside from displacing within a uv shell only and not letting it touch the seam edges I'm not sure how else to go about this. I do know about smoothing seam angles beyond 90 degrees but I'm not sure what the best practices are.

Most of my displacement I viewed in Painter but I intent on rendering it with vray next in maya so I'm not sure if there is some trick or feature in vray next that can displace without splitting at any seam edge.

Yerus

I had that problem during my hole college and no one ever solved it, I tried everything myself till someday by chance I watched the solution and understood what was causing the problem. It was the scalar difference between ZBrush and Maya. Displacement maps are scale-dependant, and ZBrush typically shrink down the models, you got to get it right before exporting to Maya. That may not be your case, but just try to do that and see. There are two techniques I know that you can choose from:
- One is by setting 'export' tab under 'Tools' menu accordingly to the value that u had to rescale the model in Maya. https://www.youtube.com/watch?v=MlKURPhoz84
- Two is by using 'scale master' ZPlugin by reaching out the most approximate dimensions  of the model and fine tuning them: https://www.youtube.com/watch?v=X-JqryNf9xg

Good luck!

3D4Eva

Thank you. My issue wasn't due to scales mismatching. I can create a few buildings and displace bricks out but at the edges the building will split at the edges sadly. Those edges are also uv seams which are not avoidable as even a single UV shell still has seams (the surrounding edges of the shell)

Obscura

If they are one uv island, and one smoothing group, it should not break. Well. Even if they are multiple shells. So I guess you have a hard edge there.

Yerus

Um.. is it 100% on using displacement rather than normal maps? 
Just checking but, you're subdividing the mesh right? When exporting to SP you need to be sure the mesh has enough subdivs to handle the displacement.

kittinzaa

I understand what you are talking about.
In Unreal there is a thing call "Crack free displacement" that solves this problem.
but I don't see any other software could do this yet.

Obscura

Haloo!! Make sure you don't have a smoothing split on the edge and then it won't break.

Eric Chadwick

Read the V-Ray help file for displacement, there's a solution there for uv cracks.