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Answered: Sculpt layer surface high frequency distortion bug!

ZBrush Usage Questions
#1

I finally isolated this, I’m seeing it when using sculpting layers, and it’s making a mess of detailed surfaces.

When using sculpt layers, if you use the transpose tools or the deformation tools on any portion of your mesh while a layer is in record mode, you will end up with undesired surface noise corruption on the portion of the mesh you transformed! This high-frequency distortion appears as you turn OFF record mode, and each time you enter and leave record mode on that layer, the distortion is amplified. Smoothing the noise away within the affected layer removes the noise but only until the record mode is again turned off. The distortion seems to be proportional to the distance each point has moved from its original (non-layered) position. Layers created _after_ a transpose operation (even if that operation was done in another layer) are not affected unless they also use transpose. It is possible to use a secondary layer to smooth away the noise created in a previous layer, but the noise returns when that previous layer is edited once more. Additionally, if using a 'smoothing layer', turning off the visibility of the layer with transpose causes the inverse of the noise to be seen, unless the smooth layer is also turned off. There is no way that I've found to use the transpose tools within a layer without generating this noise. exporting/reimporting and morph targets did not seem to provide a way to circumvent the problem.


Note, the transpose and deformation tools provide the most obvious way for this problem to occur – regular sculpting brushes ALSO exhibit the problem if they create a big enough displacement from the original (non-layered) position of each point.

This problem is extremely easy to reproduce, If anyone finds a way to recover or avoid the problem, I'd love to hear it. I'm surprised nobody's seen it yet.... to reproduce: 1) create a sphere 3D. 2) make it a polymesh 3d. 3) subdivide it two or three times (the distortion is too high frequency to cause noticeable perturbation in coarse mesh detail) 4) Create a new layer. 5) using transpose, move the mesh a decent distance to the left. (about 4 to 5 sphere diameters is plenty) 6) switch to rotate without changing the transpose line (move doesn't have as much effect as rotate), and rotate the sphere about 45 degrees downward 7) turn off record mode and examine the surface of the sphere. Use one of the zsketch materials or bump viewer to get a good visualization of the noise 8) turn on and off record mode a few times and watch the noise get worse. 9) find a way to fix it and tell me!

#2

Thanks for the steps to duplicate this. I’m bringing it to the attention of the development team.

#3

Hi, another example please help!!!

Attachments

NOISE CORRUPTION.jpg

#4

Sorry if this has already been addressed, but I haven’t been able to find the solution to this anywhere on the forums and I am currently running into this problem with version 4r4. This is the first time it is happening actually.

I unfortunately can’t provide a screenshot though.

I’ve tried resolving it by turning recording the layer, smoothing things out (which is destructive to the desired details), turn record off, and the artifacts return to the surface.

I also noticed the distortion is ringed, as if it is being projected and stretched onto the surface.

Only solution I can think of: Bake the layer down, making the transpose permanent. Then resculpt :\