%% gh
%% Arbre d'une expression logique
autocrop
%% échelle et étendue de l'image
60 setxunit
1 8 setxrange
-.5 4.5 setyrange

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% définitions des couleurs
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/coul0 {0 0 0 0.5 setcmykcolor} def %gris
/coul1 {noir} def
/coul2 {orange} def
/coul3 {rouge} def
/coul4 {bleu} def

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Les feuilles de l'arbre
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
coul1
1.5 setlinewidth
15 setfontsize
5 setdboxit 		%% reglage bordure de l?encadrement 
/linearc .1 def 	%% pour arrondir les angles 
setPalatino
/levelsep 1 def
/treesep 2 def

/treehooki {/treesep 1 def} def
4 4 (Et) Tb rootnode
[down
   (Ou) Tb [
      (p) Tb (q) Tb]
   (Ou) Tb [
      (Non) Tb [(p) Tb]
      (Et) Tb [
         (p) Tb (Non) Tb [(q) Tb]
      ]
   ]
] tree