Hi Thomas, degenerate faces and degenerate polyhedra are quite useful for what you want to do. A flat, degenerate polyhedron can be generated from even more degenerate triangles like this: module polyhedrify_points(points) { faces = [for(i=[0:len(points)-1]) [i,i,i]]; hull() polyhedron(points, faces); } polyhedrify_points([[2,2,2], [2,8,8], [7,2,2], [7,8,8]]); // Or for a non-degenerate result: //polyhedrify_points([[2,2,2], [2,8,8], [7,2,2], [7,8,8], [0,0,10]]); >From the above it is trivial to linear extrude by some vector v. One way for this is to hull with the translated result: hull() for(i=[0,1]) translate(i*[-2,-6,0]) polyhedrify_points([[2,2,2], [2,8,8], [7,2,2], [7,8,8]]); Degenerate faces and degenerate polyhedra are not documented in OpenSCAD. So I am not sure if the above will remain possible in all future versions. Maybe someone can tell. I am using 2015.03-2. Martin www.panohero.de -- Sent from: http://forum.openscad.org/