% D. Roegel January 2001 % roegel@loria.fr input 3danim input 3dgeom output_res:=72; drawing_scale:=2cm; vardef def_C(expr inst)= new_obj_points(inst,12); % 12 points set_C_points(inst); enddef; vardef set_C_points(expr inst)= set_point(1)(0,0,0);set_point(2)(0,0,1); set_point(3)(0,1,0);set_point(4)(0,1,1); set_point(5)(1,0,0);set_point(6)(1,0,1); set_point(7)(1,1,0);set_point(8)(1,1,1); % vanishing points def_screen_pl(screen); new_line(l)(1,2); if not def_vanishing_point_p_l_pl(9)(l)(screen): message "no vanishing point 1"; set_point(9)(0,0,0); fi; set_line(l)(1,3); if not def_vanishing_point_p_l_pl(10)(l)(screen): message "no vanishing point 2"; set_point(10)(0,0,0); fi; set_line(l)(1,5); if not def_vanishing_point_p_l_pl(11)(l)(screen): message "no vanishing point 3"; set_point(11)(0,0,0); fi; set_line(l)(1,7); if not def_vanishing_point_p_l_pl(12)(l)(screen): message "no vanishing point 4"; set_point(12)(0,0,0); fi; free_line(l); enddef; vardef draw_C(expr inst)= draw_lines(1,2,4,3,1);draw_lines(5,6,8,7,5); draw_line(1,5);draw_line(2,6);draw_line(3,7);draw_line(4,8); pickup pencircle scaled 4pt; drawoptions(withcolor red); if z[ipnt_(9)]=(10,10):draw_line(9,9); fi; if z[ipnt_(10)]=(10,10):draw_line(10,10); fi; if z[ipnt_(11)]=(10,10):draw_line(11,11); fi; if z[ipnt_(12)]=(10,10):draw_line(12,12); fi; drawoptions(); pickup pencircle scaled 1pt; draw_line(9,9);draw_line(10,10);draw_line(11,11);draw_line(12,12); pickup pencircle scaled 0.4pt; drawoptions(dashed evenly scaled 0.5); for j:=1,3,5,7:draw_line(j,9);endfor; for j:=3,4,7,8:draw_line(j,10);endfor; for j:=1 upto 4:draw_line(j,11);endfor; draw_line(1,12);draw_line(2,12); drawoptions(); enddef; new_plane_(screen)(0,0,0); % must be defined before |assign_obj| % because |assign_obj| calls |set_C_point| % on change le champ car on est très près h_field:=160; % degrees v_field:=160; % degrees assign_obj("cube","C"); %for i:=0 upto 100: i=97; beginfig(100+i); % Observator set_point_(Obs)(1.8*cosd(3.6*i),1.8*sind(3.6*i),2); Obs_phi:=90;Obs_dist:=0.5;point_of_view_obj("cube",8,Obs_phi); reset_obj("cube"); draw_obj("cube"); endfig; %endfor; end.