COMMENT ⊗   VALID 00004 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	% This page should match page 2 of MANUAL.MF,
C00004 00003	"Figure Da" % Neenie's problem
C00009 00004	end
C00010 ENDMK
C⊗;
% This page should match page 2 of MANUAL.MF,
% because I'm testing stuff to add to that file

def clear_all = clearit; clearxy; pickup standardpen;
proofrulethickness 0;
enddef;

def heavy_dot expr z =
 makelabel.top("",z-(1,0));
 makelabel.top("",z+(1,0));
 makelabel.top("",z-(0,1));
 makelabel.top("",z+(0,1));
 makelabel.top("",z+(1,1)/sqrt2);
 makelabel.top("",z+(1,-1)/sqrt2);
 makelabel.top("",z-(1,1)/sqrt2);
 makelabel.top("",z-(1,-1)/sqrt2);
 enddef;

def font_setup=
define_pixels(u,tiny,axis,hheight,border);
define_blacker_pixels(hair,thin,thick,rulethickness);
pickup if tiny<.5: nullpen else: pencircle scaled tiny fi;
tinypen:=savepen;
currenttransform:=identity slanted slant yscaled aspect_ratio;
enddef;

mode=proof; mode_setup;
standardpen=savepen;
"Figure Da"; % Neenie's problem
clear_all;
z1l=(0,240-y); z1r=(15,288-y);
z0l-z0r=z1l-z1r; z0r=(144,189-y); y0l=0;
pickup pencircle scaled 2;
numeric a,b,c,d;
a=x1l; b=y1r; (c,d)=z0r;
draw z0l--z0r--z1r--z1l--cycle;
proofrule((a,d),(a,b)); proofrule((a,b),(a-d+b,b));
for z=z0l,z0r,z1l,z1r,(a,b): heavy_dot z; endfor
makelabel.bot.nodot("≤",z1r+(3,-8));
makelabel.lft("(a,b)",(a,b));
makelabel.top("z1r",z1r);
makelabel.lft("z1l",z1l);
makelabel.rt("(c,d)",z0r);
makelabel.lft("z0r ",z0r);
makelabel.lft("z0l ",z0l);
showit; shipit;
end