ZBrushCentral

zBrush, my old Nemesis. Once again...

ZBrush Usage Questions
#1

I didn’t create any displacement maps in the last few years. And now, that I modeled everythig and actually want to create my displacement map, it’s going wrong. Like always.

There are just a few tiny details on my sculpt, but when I return to the lowest subD level and generate the map, it’s not only a few tiny details that get baked, but the whole thing looks like a cavity map. Large areas with bright and dark parts, even nothing got touched in there.

Just for a test: Load an obj, subdivide it a few times, go back to level one and voila, you’ll end up with a displacement map which isn’t neutral gray, but a very modulated black and white image (again the ambient occlusion feeling). What for h… sake do I need to do that my displacement map shows only the stuff I actually modelled? If one would apply this map to a none subdivided mesh in the exzternal application and use displacement, it might look right, but usually your mesh get’s subdivided a few times anyway. So the details just get added on top of that.

So the big question, what do I need to do in order to get only the fine detail (looking more like a bump map would look like) and not the displacement map which looks totally wrong for a subdivided mesh?

Thanks for any help. I always run into this disaster…

Cheers
Thomas

P.S.: Why does zBrush calculate the displacements like this any way? Looks totally strange to me.

#2

O.k., in order to avoid the difference between the unsubdivided mesh and the high poly one which is visible in the displacement, I subdivided another mesh to the same highest sub d level, deleted the lower ones, stored a morph target and “projected all” to it from my sculpted mesh.

Looks fine to me. Klicking between the morph and the normal mesh gave me either the “clean” mesh or the details. Fine! Let’s press the displacement map button. Oh! Map cannot be created while the highest subd-level is active!

I deleted all levels! This is the lowest one!

Aaaargh!

#3

Re-imported the base mesh. Didn’t help. Still get this funky displacement map which result in a bloated object if used.

I tried it with the star object inside zBrush. Store MT, subdivide, sculpt, go back to level 1 and create a displacement map. All is fine.

If try to do this with my mesh, big mess.

If I reimport my base mesh as another subtool, both meshes (the sculpted one and new one) look the same. No polys are jumping except from the areas where I sculpted.

First I store a morph target for the clean mesh. Subdivide it to the same level as the other and go with the sculpted on to the highest subD level. No I project all. Go back to the lowest level, switch the MT and create my displacement. Still the same mess. A map which would inflate my mesh like a balloon.

What - am - i - doing - wrong!!!

#4

You’d be better off showing us pictures, it would be easier to diagnose.