beginchar("b",.4em#,4cap#/7,dth#); "beta"; 
picture BHTA;
path p[];
 save ww,hh;

 ww = w/4; hh = h/4;
 b := .3ww;

 z0 = (.7ww,-.8hh);
 z1 = (.5ww,3hh);
 x2 = x6 = 2ww;
 y6 = 4hh - y2 = 0;
 y5 = 4hh - y3 = 1hh;
 x3 = 3ww; x5 = 3.5ww;
 x4 = 1.5ww; y4 = .7[y2,y6];

 penpos0(1.5b,0);
 penpos1(b,0);
 penpos2(2b,270);
 penpos3(b,180);
 penpos4(2b,angle(z4-z3) - 90);
 penpos5(1.2b,180);
 penpos6(2b,90);
 penpos7(b,0);
 penstroke z0e..z1e{up}..z2e{right}..z3e{down}..{z4-z3}z4e;
 p0 = z0..z1{up}..z2{right}..z3{down}..{z4-z3}z4{z5-z4}..z5{down}..
 {left}z6;
 z7 = point .6 of p0;
 z8 = point 4 of p0;
 penpos8(3b,angle(z3-z8) - 90);
 penstroke z8e{z5-z4}..z5e{down}..{left}z6e;
 penstroke z6e{left}..{up}z7e;
 BHTA = currentpicture;
endchar;