Alan Cox pointed me long ago to implicitcad, because it implements fillets and chamfers by rounding intersections and unions. I kept meaning to play with it…

Tonight my wife asked me whether I could 3D print a set of catenary arch blocks as math teaching aids. To my surprise, I couldn’t find a set to print. I saw that ImplicitCAD (unlike OpenSCAD) implements cosh() and figured it was the right tool for the job. Sadly, I find no way to define arbitrary polyhedra in ImplicitCAD. git grep polyhedron in the source code comes up empty. There’s no hull or loft or minkowski sum, either. So I guess back to OpenSCAD and do it the hard way.

(Originally posted on Pluspora)