# ## a cylinder # algebraic3d curve2d outer=(8; -2, -2; 0, -2; 2, -2; -2, 0; 2, 0; -2, 2; 0, 2; 2, 2; 4; 3,2,3,5; 3,5,8,7; 3,7,6,4; 3,4,1,2); curve3d pathcurve1 = (2; -2,2,0; -2,2,-10; 1; 2,1,2); solid ext = extrusion(pathcurve1; outer; 0,0,1);