ZBrushCentral

Dividing changes base model?!?!?!?

ZBrush Usage Questions
#1

Hi

I just bought a version of zbrush 4 for my company…and it is behaving in a way I didn’t expect. If you:

  1. import a mesh very low res (or start with a cube or something)
  2. divide it several times so it’s nice and smooth
  3. set your subdivision level back to the most basic level

It’s changed!!! It’s a bit smoothed/relaxed. I haven’t anything except divided my model, and zbrush has changed the base mesh. That’s actually REALLY bad, and I was wondering is there was a way to turn this off…to preserve the base mesh shape during the dividing process. The base mesh should only change as a result of my sculpting, not just from subdividing.
Any ideas?

#2

store a MT (morphTarget) before you divide.
or you can import you orginal mesh back into the mesh while it is in edit mode and at it’s lowest subD

#3

Hmmmm…I tried that. Problem is that when I “switch” back to my morph target, I lose the large-scale sculpting that occurred between the first and second levels.
Is there some way to restrict the “large” changes to the second level geometry instead of the first? (keep the first the same)
I found this thread
http://lounge.ego-farms.com/showthread.php?p=14141

sounds similar but they didn;t seem to really find a solution

#4

sorry, so i don’t sound like a total moron here, I’ll mention what this is for

I am working with a model which already done, textured, rigged, animated, etc etc.
client wants extra musculature added…small details…even some large detail like fatter legs and such.

I am trying to find the best workflow here without screwing up any of the work already done. My thoughts are to do it soley with a discplacement texture, or alternately, doing my changes in zbrush and bringing in the base model as a morph target and then displacement for details. did that make sense?

#5

What you need to understand is how multi-resolution mesh editing operates.

Edits that you make to one level are propagated to other levels when you change levels – not when the edits are actually made.

What this means is that you can store a morph target at level 1, divide and sculpt, return to level 1 and switch to the stored morph target to create your displacement map or whatever. Before returning to the higher levels again, switch morph targets again. This returns level 1 to the multi-res state so that it’s not seen as a change in size when you change levels.

Dividing a model smooths the surface. This involves a contraction of the model. ZBrush sees this as a change to the model, which is why your model is smaller when you return to level 1. But the method described above allows you to temporarily switch back to your original base mesh without affecting the higher levels. Just don’t return to the higher levels without switching morph targets again.

If you forget to store a morph target before dividing, all is not lost. Return to level 1, store a morph target and import your original model. You now have a base state and a multi-res state that can be toggled between with the morph target just as if you’d stored one before dividing.

#6

So, ill shoot here in the dark, actually not had this problem.
But, so what if the basemeshe changes ?
You have UVs. SO, make your modeling and export the maps you need and apply them to the original mesh ?! (Just dont turn ON Smooth UVs when creating maps).

I think this should wokr ?

#7

Aurick solved it…at least he explained it to me. 3d programs like max and maya and whatever, do not change the base level upon smoothing, which is what caused the confusion on my part. However ghost666 also had it right…if i use a morph target to begin with, and then switch to it afterwards, the geometric changes are still inside BEFORE i switch back to higher levels.

short story is this is my solution considering i want to contain ALL of my changes within discplacement information, instead of altering the existing model in max.

Pimento…to answer, I need he lowest level model unchanged so that the huge sweeping changes (like a fatter leg) will be included in the displacement information. not sure if that made sense.