Offset spline surfaces without self-intersection

[amstuff]

I was wondering if there is a way to offset a spline surface in a way that avoids self-intersection.

From my (limited) research it looks like Parts offset feature mainly wraps the respective OCCT feature.
https://www.opencascade.com/doc/occt-7. ... shape.html unfortunately states, that avoiding self-intersection is an unimplemented feature in OCCT.

Is there maybe another way to get the desired result?

[microelly2]

The self intersection occurs in koncave areas.
So a workaround is to cut these areas, offset the rest and fill the gap with other faces.

[amstuff]

Thanks microelly2! That's of course a valid solution.

However, I forgot to mention that I need to do a lot of offsets on different surfaces (with varying curvature), so manually working around self-intersections really isn't an option for me. I was kind of hoping this had already been implemented somewhere in FreeCAD.
Do you know of any existing way to get offsets, that are free of self-intersections?
Otherwise I'll have to look into implementing it myself, but am really trying to avoid that.

[microelly2]

The only way I know is multidimensional dilation with scipy.

https://docs.scipy.org/doc/scipy-0.14.0 ... y_dilation

the adventure is to come back from the point cloud to a approximated surface.