input geometriesyr15; figure(-2cm,-2cm,4cm,4cm); pair A,B,C,D,E,F,G,H,O,I,R,S,T,U; path reservoir,dessus,dessous; E=(0cm,0cm); H=(2cm,0); F=(0.8cm,0.5cm); G=(2.8cm,0.5cm); A=E shifted (0,2.2cm); B=F shifted (0cm,2.2cm); C=G shifted (0cm,2.2cm); D=H shifted (0cm,2.2cm); R=E shifted (0,0.6cm); S=F shifted (0cm,0.6cm); T=G shifted (0cm,0.6cm); U=H shifted (0cm,0.6cm); O=iso(E,G); I=O shifted (0,-1cm); draw A--E--H--G--C--B--cycle; draw A--D--H--G; draw E--H; draw D--C; draw I--H; draw E--I--G; draw O--I dashed evenly; draw E--F--I dashed evenly; draw B--F--G dashed evenly; reservoir=R--U--T--G--H--E--cycle; dessus=R--S--T--cycle; dessous=R--U--T--cycle; draw hachurage(E--I--G--H--cycle,30,0.3,1); draw hachurage(dessus,20,0.1,1); draw hachurage(dessous,20,0.1,1); draw hachurage(reservoir,30,0.3,1); draw R--S--T--U--cycle; label.ulft("A",A); label.ulft("B",B); label.urt("C",C); label.ulft("D",D); label.lft("F",F); marque_p:="croix"; nomme.lft(O); label.llft("E",E); label.lrt("H",H); label.rt("G",G); label.bot("I",I); fin; end