I can get something to render fine if I do "arches2()", but if I do "difference, mirror; mirror" I get some odd error. In cases like that, we suspect the object in question is not a manifold. So check if arches2() is a manifold.

What do I do to check if it is manifold or not? <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Thu, Mar 8, 2018 at 6:33 AM, Ronaldo Persiano <rcmpersiano@gmail.com> wrote: > > I can get something to render fine if I do "arches2()", but if I do > "difference, mirror; mirror" I get some odd error. > > > In cases like that, we suspect the object in question is not a manifold. > So check if arches2() is a manifold. > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

What do I do to check if it is a manifold or not? If you are using polyhedron to build arches2 (), check if each edge are common to exactly 2 facets and that you have face winding order consistent to what is prescribed in the OpenSCAD manual.

Or just union it with a unit cube and see if CGAL throws an error. On 8 March 2018 at 14:52, Ronaldo Persiano <rcmpersiano@gmail.com> wrote: > > What do I do to check if it is a manifold or not? > > > If you are using polyhedron to build arches2 (), check if each edge are > common to exactly 2 facets and that you have face winding order consistent > to what is prescribed in the OpenSCAD manual. > > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >