My gravatar in ConTeXt with MetaPost

gravatar.tex

\startMPpage
numeric u; u := 10pt ;
picture eighth, quarter;
path p, q;

drawoptions(withcolor(166/255,165/255,177/255)) ;

eighth := image (
    fill origin -- (u,0) -- (u,u/2) -- cycle ;
    fill (0,u) -- (u,u) -- (u,u/2) -- cycle ;
    fill origin -- (u/2,u/2) -- (0,u) -- cycle ;
) ;

quarter := image (
    p := origin -- (u/2,0) -- (u/2,u/2) -- cycle ;
    fill p shifted (-0,0) ;
    fill p shifted (0,u/2) ;
    fill p shifted (u/2,u/2) ;

    draw eighth shifted (u,0);
    draw eighth shifted (0,u);

    p := (u/2,0) -- (u,u/2) -- (u/2,u) -- (0,u/2) -- cycle ;
    q := (u/2,u/4) -- (u/4,u/2) -- (u/2,3u/4) -- (3u/4,u/2) -- cycle ;
    eofill (p -- q -- cycle) shifted (u,u) ;
) shifted (-u,-u) ;

draw quarter rotated (  0) shifted (0,0) ;
draw quarter rotated ( 90) shifted (2u,0);
draw quarter rotated (180) shifted (2u,2u) ;
draw quarter rotated (270) shifted (0,2u) ;
\stopMPpage