Geometriesyr16 - Exemple 7

 verbatimtex
 %&latex
 \documentclass{article}
 \usepackage[frenchb]{babel}
 \begin{document}
 etex
 
 input geometriesyr16;
 
 

 figureespace(-10u,-10u,10u,10u);
 Initialisation(5,-15,25,500);
 color O,N,X,Y,B,L,O';
 O=(0,0,0);
 N=(0,0,1);
 X=(0,-1,0);
 Y=symetrie(X,O);
 color P,Q,R,Q';
 P=(cosd(-70),sind(-70),0);
 Q=(1,0,0);
 Q'=(cosd(60),0,sind(60));
 R=(cosd(30),sind(30),0);
 B=(cosd(-70)*cosd(60),sind(-70)*cosd(60),sind(60));
 L=(cosd(30)*cosd(60),sind(30)*cosd(60),sind(60));
 O'=(0,0,sind(60));
 path ch,cv,mg,mb,ml,mbl,gcbl;
 ch=cercles(O,X,O,X,(1,0,0));
 cv=cercles(O,Y,O,Y,N);
 mg=cercles(O,(1,0,0),O,(1,0,0),N);
 mb=cercles(O,P,O,P,N);
 ml=cercles(O,R,O,R,N);
 mbl=cercles(O',B,O',B,(cosd(20)*cosd(60),sind(20)*cosd(60),sind(60)));
 color Nr,Nrr;
 Nr=Normal(O,B,L);
 Nrr=Normal(O,B,Nr);
 trace subpath(0,length ch/2) of ch;
 trace subpath(length ch/2,length ch) of ch dashed evenly;
 trace subpath(0,length cv/2) of cv;
 trace subpath(0,length mg/4) of mg withcolor vert;
 trace subpath(0,length mb/4) of mb withcolor violet;
 trace subpath(0,length ml/4) of ml withcolor orange;
 trace subpath(0,5*length mbl/18) of mbl withcolor rouge;%cutafter segment(O',L)
 marque_p:="croix";
 pointe(P,R);
 nomme.top(N);
 nomme.bot(B);
 nomme.llft(L);
 label.llft(btex 70\degres\ Ouest etex,Projette(P));
 label.lrt(btex 30\degres\ Est etex,Projette(R));
 label.bot(btex 0\degres\ (Greenwich) etex,Projette(Q));
 trace chemin(P,O,N);
 trace segment(O,Q);
 trace segment(O,R) cutbefore mg;
 trace segment(O,R) cutafter mg dashed evenly;
 trace segment(O,B) dashed dashpattern(on12bp off6bp on3bp off6bp);
 trace chemin(B,O',Q');
 trace segment(O',L) cutafter mg dashed evenly;
 trace segment(O',L) cutbefore mg;
 path cod;
 cod=cercles(O,1/3[O,N],O,1/3[O,N],P);
 cod:=cod cutbefore demidroite(O,B) cutafter demidroite(O,P);
 trace cod;
 label.lft(btex 60\degres etex,point(length cod/2) of cod);
 gcbl=cercles(O,B,O,B,Nrr);
 trace gcbl cutbefore (subpath(0*length cv/4,length cv/4) of cv) dashed evenly withcolor bleu;
 trace gcbl cutafter (subpath(3*length cv/8,3.5*length cv/8) of cv) dashed evenly withcolor bleu;
 trace gcbl cutbefore demidroite(R,L) withcolor bleu;
 finespace;
 end