SolidClassifier problem with a torus

I have a strange problem I thought I would ask about here before poking around too deeply... I build a toroidal solid from bottom up using arcs, ruled faces, planar faces with multiple wires, etc. When I use BRepClass3d_SolidClassifier to determine when points are in or out I get the wrong answer (OUT instead of IN and vice versa, I think ON is correct). However if I write the solid out to a step file and then read it back in, I get correct behavior. I don't see this problem with simple shapes (non-toroidal). Any ideas what I might be doing wrong? I build a shell with BRepAPI_Sewing, adding the faces in a more or less random order - does this matter? Do I need to be concerned with face orientation?


Forum supervisor's picture

Dear Wayne,
If it's possible we would be pleased to get a script or sample to reproduce the specified problem.

wayne606's picture

Thanks for the help. I was working on the test program to show the problem and ran into a different issue... I create some arc edges and a wire, and the bounding box of these is correct. Then I make a face from the wire, and the bounding box of that face is wrong. I build the incremental mesh for the face as discussed several times in this forum but it doesn't seem to help ... Any thoughts?

wayne606's picture

I see the problem. The solid has negative volume so I do in fact need to be concerned with face orientation.