open Graphics ;;
open_graph "" ;;

let arrondi x_float =
  let x_int = int_of_float x_float in
  let différence_float = x_float -. float_of_int x_int in
  if différence_float > 0.5 then
    if différence_float < 0. then
      x_int - 1
    else
      x_int + 1
  else
    x_int ;;


let avance distance angle =
  let (x_courant_int,y_courant_int) = current_point() in
  let x_courant_float = float_of_int x_courant_int
  and y_courant_float = float_of_int y_courant_int in
  let x_cible_float = x_courant_float +. distance *. (cos angle)
  and y_cible_float = y_courant_float +. distance *. (sin angle) in
  let x_cible_int = arrondi x_cible_float
  and y_cible_int = arrondi y_cible_float in
  lineto x_cible_int y_cible_int ;;

let pi = 3.1415926535 ;;
let pi_sur_trois = pi /. 3. ;;

let rec motif generation distance angle = match generation with
  0 -> avance distance angle
| n -> let nouvelle_distance = distance /. 3. in
           motif (n-1) nouvelle_distance angle ;
           motif (n-1) nouvelle_distance (angle +. pi_sur_trois) ;
           motif (n-1) nouvelle_distance (angle -. pi_sur_trois) ;
           motif (n-1) nouvelle_distance angle ;;

clear_graph();;
moveto 10 10;;
motif 0 300. 0.;;
moveto 10 50;;
motif 1 300. 0.;
moveto 10 150;;
motif 2 300. 0.;;
moveto 10 250;;
motif 3 300. 0.;;
moveto 10 350;;
motif 4 300. 0.;;
moveto 385 10 ;;
motif 5 300. (pi /. 2.);;
moveto 435 10 ;;
motif 6 300. (pi /. 2.);;

 while not(key_pressed()) do
   ()
 done;;