ZBrushCentral

Is Zbrush subdividing existing levels slow?

ZBrush Usage Questions
#1

At some point at work I started wondering about that. This model has 8 subD levels topping at 15 mio polys…with 3 separate layer details added so far. It feels like Zbrush is having a hard time stepping up and down between the subD levels - also when parts of the model is isolated.

It’s not unusual to wait sometimes 7-10 seconds moving up and down, especially between the top levels. Probably a minor detail but it can get really annoying during a daily workflow. You just want those existing levels to shift instantly - no delay! :smiley:

Wel maybe my settings is wrong? Any know?

I work on a windows 7, dual quad core I7 processor system with 12 gigs of memory.

My Mem settings in Zbrush is:

  • Compact Mem: 4096
  • Doc Undo: 4
  • Tool Undo: 4
  • MaxPolyPerMesh: 21.2806
  • HD Preview MaxPoly: 10.64

Cheers!

#2

Your settings are right for your system. It’s simply that a 15 million polygon model with four additional layers is in fact a 60 million polygon model. That’s a lot of data to be throwing around, and this especially comes into play when switching levels. It becomes even more prominent when part of the mesh is hidden due to the fact that ZBrush must also extrapolate the hidden part across the level change.

I believe that you’ll find that going down in level is more challenging than up in this case because when going down ZBrush must also adjust the edges of the visible area to compensate for partial polygons. (Each polygon of course divides to become 4. But if only 1, 2 or 3 of those sub-polys are visible at the higher level, ZBrush must determine whether the lower level polygon will be visible or not upon dropping down in level. That calculation takes a little extra time.)

#3

Thanks for a very detailed reply, Aurick. It helped a lot in understanding the process here. You are the Zbrush Über Lord :cool:

#4

Yes, thanks for the reply.
Those are big delays for me. 4 layers, 17m polys.
I wouldnt let things get so out of control, but im texturing something already rigged, and the bad UV’s force me to go up up up as zbrush is heavily dependent on polypaint.
Thanks again.