Help with the Clip Brushes in Zbrush

LaJolly

I am trying to use the Clip Rectangle and Clip Circle tools. When I use one of the tools to draw out a shape on some mesh, whatever is outside of the mesh will vanish. When I select Alt, the inside of the selection does not vanish as I presume it should do the opposite of the first function. Does anyone know how to get the clip rectangle and clip circle tools to delete the interior of the selected shape, rather than the exterior? Thank you!!

Bartalon

Sounds like you should just use dynamesh booleans for something like that.

Alternatively you can use SliceRect (but with a circle) to create a separate polygroup and delete it or extrude it inward.

Dantert

Bartalon is right, but if you don't want to dynamesh all to have a clean surface you can also try to create a new polygroup with the shape of the hole you need from each sides of the mesh, just use the slice cyrcle or the other slice brushes(ctrl+shift) then select the rest that you want to keep and delete hidden, then select the CurveBridge brush from the menù and with shift+drag go over the borders of the hole, in that way you'll create two curves of the shape of the holes and zbrush will recalculate the hole with new geo. It's actually a pretty cool ctrick to keep the res down.

cryrid

I'd favor slicing as well. Clip brushes don't modify the topology, they just push vertices around and mash them together. You can read about its behavior (including the alt function and the importance of the crosshair on the rectangle/circle brushes) at http://docs.pixologic.com/user-guide/3d-modeling/hard-surface/clip-brushes/