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Overlap? Messed up meshes keep occuring

Hi - well I have another problem with Zbrush.

I have created a tool and carved things with build clay and Smooth brush.
And it ends up with…overlapped meshes? Well when I switch to SHIFT + F mode and show the mesh grids, the mesh shows a mix of green and red and these are the bits that seem to be what is called “non-manifold” faces or whatnot. Anyway, it’s causing problems.

I haven’t done anything fancy, and yet, it’s causing so much of these weird bits here and there. No amount of smoothing does the trick, nor Geometry>Fix Mesh.

Says “Mesh integrity is complete” but when I export this model, obvisoulsy it’s an issue.

What more can I do? I mean, just sculpting normally causes this, is this a fault in the software??

Edit

I “undo”-ed a few steps and the issue seems to stem from how Zbrush messes up the polyframe. The “webbing” or the “frame” whatever its name is, the lines that defined the polygon gets knotted up like a messy tangle of strings. “Smooth” apparently exacerbates that and does nothing to “untangle” these messed up webs of the polygon.

God, if there’s a way to manually untangle these lines line-by-line I’d do it. I don’t know why on earth this mesh is so messed up… I hope to God I don’t need to redo the past 9 hrs of work that got me up to here…

HI @JTG ,

I can’t tell you what in your process caused this, only to assure you that it was indeed something in your process.



Just a quick note. If you are new to ZBrush and you just want to jump right into quick sculpting without any topological concerns or the need to familiarize yourself with basic program feature documentation, restart ZBrush and load the DefaultProject.zpr from Lightbox. Activate Sculptris Pro mode (supports many but not all brushes), and just start sculpting on the default poly sphere. Use Dynamesh periodically to clean the mesh up and redistribute the polygons.



As to your problem here I see a few things.

  1. It looks like the mesh has been partially subdivided. This might happen if any section of the mesh was either hidden or masked when the “Subdivide” button was pressed. This would cause that area to be locally subdivided, but the mesh will not be smoothed and it will create geometry that performs poorly for sculpting in the areas where a surface of one level of resolution must connect to a section with smaller, denser polygons. You can see a lot of poles where the two areas of differing resolution intersect.

  2. It looks like the geometry includes the radial topology from a sphere primitive where all the edges converge into a single point on the top of the sphere. This type of triangulated radial topology will also perform poorly. ZBrush loves well distributed quads, as close to square-shaped as possible, for most purposes.

  3. I cannot tell from your screenshot whether you actually have a separate, duplicate section of mesh there, or if the polygons have simply been problematically stretched and mashed together. You may simply have different polygroups there which could have been created as a part of any number of operations. With polyframe mode on, clear any masking and run a Smooth brush over that area to relax the points and move them futher apart. This may show you whether you are actaully looking at overlapping mesh section, or rather p[olygons on the same mesh that have become twisted and compressed.



If still in the early stages of the model and making frequent changes to the form, this is an ideal use case for Dynamesh. Activate Dynamesh for the mesh and it will resurface the entire mesh, redistributing the polygons so they again perfrom well for sculpting.

It will also clean up these areas for you, and eleminate overlapped geometry.

After you resurface the mesh, try activating Sculptris Pro mode for your sculpting brushes. This mode adds geometry to the mesh in real time as you sculpt, which will prevent poly stretching. Over time, this may result in especially dense sections of geometry with more polygons than are actively needed. These areas may not perfrom well for sculpting, and may generally reduce the performance of the mesh from unnecessary polycount. Use Dynamesh periodically to again redistribute the geomertry to make the mesh surface perform well for sculpting.

:slight_smile:

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