1group(); 2group(); 3group(); 4group(); 5group(); 6group(); 7group(); 8group(); 9group(); 10group(); 11cube(size = [1, 1, 1], center = false); 12sphere($fn = 0, $fa = 12, $fs = 2, r = inf); 13cylinder($fn = 0, $fa = 12, $fs = 2, h = inf, r1 = -inf, r2 = -inf, center = false); 14group(); 15group(); 16group(); 17 18