use label="";
col x {box a, b, c, d;}
col y {box a, b, c, d;}
col z {box a, b, c, d;}
col v {box a, b, c, d;}

use line.radius=5, line.type=dotted;
around x.a+v.a box A1;
around z.a+z.c box A2 [imargin=10];
around x.c+x.d *oval A3;

join A1+A2+A3 [fill.color=lgray+50,
              draw_before=x];