my_model(x[3], a[1]) { array center[3]; center = [6,6,0]; cl1=hfCylinderX(x,center,2); center[2]=-6; cl2=hfCylinderY(x,center,3); center[1]=-6; cl3=hfCylinderZ(x,center,4); my_model = cl1 | cl2 | cl3; }