+ else
+
+ # manually drawing the 3x4 boundaries specified by argv ...
+ draw_cyl $bx0 $by0 $bz0 $bx1 $by0 $bz0
+ draw_cyl $bx0 $by0 $bz0 $bx0 $by1 $bz0
+ draw_cyl $bx1 $by1 $bz0 $bx1 $by0 $bz0
+ draw_cyl $bx0 $by1 $bz0 $bx1 $by1 $bz0
+
+ draw_cyl $bx0 $by0 $bz1 $bx1 $by0 $bz1
+ draw_cyl $bx0 $by0 $bz1 $bx0 $by1 $bz1
+ draw_cyl $bx1 $by1 $bz1 $bx1 $by0 $bz1
+ draw_cyl $bx0 $by1 $bz1 $bx1 $by1 $bz1
+
+ draw_cyl $bx0 $by0 $bz1 $bx0 $by0 $bz0
+ draw_cyl $bx0 $by1 $bz1 $bx0 $by1 $bz0
+ draw_cyl $bx1 $by0 $bz1 $bx1 $by0 $bz0
+ draw_cyl $bx1 $by1 $bz1 $bx1 $by1 $bz0
+
+ fi
+