ZBrushCentral

Cutting off parts of a model

ZBrush Usage Questions
#1

Hi. I really feel like a n00b these days, asking question after question, but is there a way for me to say, cut off a limb of a model with very little fixing up afterwards? If I hide parts and crop that way, it leaves holes, and I don’t really want that :stuck_out_tongue:

#2

You’re basically asking for a boolean cut. There’s no such feature in ZBrush at this time. Deleting polygons will always leave holes.

The closest you can get is by using the Flatten deformation. Depending on the nature of your model, it can get a bit tricky trying to get the result you’re after, though.

Alternatively, the only other option is to delete the polygons and then use ZBrush’s retopology features to edit the topology and construct new polygons. This actually isn’t as hard as it sounds:


  1. Select the ZSphere tool.
  2. Press Tool>Rigging>Select Mesh and choose your model with the hole.
  3. Press Tool>Topology>Select Topo and choose the model again.
  4. Press Tool>Topology>Edit Topology.
Now draw ZSphere lines that connect across the mesh. One down the center works well, followed by one that bisects across that line. (You can connect a line to an existing one at the center, only.) You can then bisect each of these new segments again. It only takes a few topology lines for ZBrush to figure out what you’re doing and fill in the rest of the hole for you. Press A periodically to see how you’re doing.

The image below shows an example where I did this after chopping off the demo head’s shoulders. The green lines are the new topology lines that I drew. I started with one that ran across the hole along the model’s center line. Then I simply bisected that line a few times in the X direction. ZBrush does construct a point in the very center of the model when you use this technique. I simply moved that point out so that the line through the middle of the mesh (front to back) ran straight across the hole.

ZBC-Image.jpg

#3

Thanks a lot! I’ll try that next time, when I didn’t find a way to do it yesterday I exported my model into Maya and did it there, but that probably took longer than it’d take, had I used this method :slight_smile:

Again, thanks :smiley:

#4

Wow it does not work here :frowning:

#5

Then you’re probably missing a step someplace. Unfortunately, “it doesn’t work” has zero value for troubleshooting purposes. We don’t know what you did. We can’t see any pictures of what’s happening. If you provide more info, we’ll try to help.

#6

Step to reproduce : (kidding)

  1. Load the mesh I want to close.
  2. Draw a Zsphere
  3. Load the mesh to edit in the rig sub menu of the zsphere.
  4. go in the topology sub menu.
  5. reload the mesh.
  6. Press edit mesh.
  7. Draw the point and lines of the mesh I want to fill.

And there is the problem once I finished it did not draw the mesh and the hole is not filled.

:slight_smile:

#7

Still need to see what you’re doing. Can you provide screen shots of what you’re drawing and the results that you get when you turn the preview on?

#8

that is the problem there is nothing to show when I press A because it doesn’t modify the mesh.

#9

Actually, pictures would help.

We need to see what your mesh looks like. We also need to see the view with the ZSpheres active so that we can see what changes you’re trying to make to the topology. If we can’t see what you’re doing, we can’t tell where you’re going wrong.

#10

[oldface_hole.jpg](javascript:zb_insimg(‘95214’,‘oldface_hole.jpg’,1,0))
this is the mesh, but I have restarted the sulpt.
See in that thread :slight_smile:
http://www.zbrushcentral.com/zbc/showthread.php?t=53057&page=2&pp=15