beginfig(116)
u:=2cm;
pair A[], B[], C[], D[], E[];
path p[];
A[0] = u*up;
for i=1 upto 10:
A[i] := A[i-1] rotated 72;
endfor;
for i=0 upto 4:
p[i] := A[i]--A[i+1];
draw p[i];
draw (point 1 of p[i]) --
( (point 1 of p[i]) + 4mm*unitvector(direction 1 of p[i]));
draw (point 0 of p[i]) --
( (point 0 of p[i]) - 4mm*unitvector(direction 0 of p[i]));
endfor
for i=0 upto 9:
B[i] := 1/2[ A[i], A[i+1] ];
endfor;
B[5]:=B[0];
for i=0 upto 9:
C[i] := .8*B[i];
endfor;
for i=0 upto 4:
p[i] := B[i] --- C[i] .. C[i+2]{dir 72i};
draw p[i];
draw (point 2 of p[i]) --
( (point 2 of p[i]) + 4mm*unitvector(direction 2 of p[i]));
draw (point 0 of p[i]) --
( (point 0 of p[i]) - 4mm*unitvector(direction 0 of p[i]));
endfor;
for i=0 upto 4:
draw subpath(1,1.4) of p[i] withpen pencircle scaled 4bp withcolor white;
draw subpath(0,1.5) of p[i];
endfor;
for i=0 upto 4:
draw A[i] withpen pencircle scaled 4bp;
draw B[i] withpen pencircle scaled 4bp;
draw C[i] withpen pencircle scaled 4bp;
endfor;
endfig;
end.