% pseudo-halftone font with 33 triangle patterns
mode_setup; q:=savepen;
w#:=7.5pt#; font_quad:=w#; designsize:=8w#;

for i=0 upto 32: beginchar(i+ASCII"0",w#,.5w#,0); pickup q;
 alpha:=.5-i/72; z0=(.5w,.5h);
 z1=alpha[(5/6w,.5h),z0]; z2=alpha[(2/3w,-.5h),z0];
 z0=.5[z2,z5]=.5[z3,z6]=.5[z1,z4]; x2=x6; y5=y6;
 draw z1--z2; draw .5[z1,z2]--z0;
 draw z3--z4; draw .5[z3,z4]--z0;
 draw z5--z6; draw .5[z5,z6]--z0; endchar;
 endfor
end.