// draw_poligon x y num len 
// draw_poligon_ugly x y next_x next_y num len angle num_acc 



import simple_graphics;
import floats;


define colore = (100 , 100 , 100);
define max_x = 800 ;
define max_y = 600 ;


define itof = \ x .
	integer_to_float x;



define find_alfa = \ num .
	(pi -f ((pi *f 2.) /f (itof num)));



// server soltanto per farlo visualizzare usando una visualizzazione del primo quadrante

define c_y = \ y .
	max_y - y;

// sono pigro a passare gli argomenti

define show_line2 = \ x1 . \ y1 . \ x2 . \ y2 . 
	show_line x1 (c_y y1) x2 (c_y y2) colore
;


define loop = fix \ f . \ x .
  f x ;


// e a scrvere il nome delle funzioni .......
	
define ftoi = \ x .
	float_to_integer x;


// non le uso piu ma non fanno male 

define deg_to_rad = \ x .
	(x *f pi) /f 180. 
;

define rad_to_deg = \ x .
	(x *f 180.) /f pi
;


define get_next_angle = \ x . \ base .
 (x +f pi +f base);


define next_xy_rad = \ x . \ y . \ len . \ angle .
	
  if ( angle <=f (pi /f 2.)) then ( ((ftoi((cos angle) *f len)) + x) ,  ((ftoi((sin angle) *f len)) + y) )

  else if ( angle <=f pi) then ( ((ftoi((cos angle) *f len)) + x) , ((-(ftoi((sin angle) *f len))) + y) )

  else if (angle <=f ((pi *f 3.)/f 2.)) then ( ((-(ftoi((cos angle) *f len))) + x) , ((-(ftoi((sin angle) *f len))) + y) )

  else ( ((-(ftoi((cos angle) *f len))) + x) , ((ftoi((sin angle) *f len)) + y) )
;



define next_xy = \ x . \ y . \ len . \ angle .
	
	next_xy_rad  x y len angle;


define draw_poligon_ugly = fix \ f . \ x . \ y . \ new_xy . \ num . \ len . \ angle . \ base_ang . \ num_acc . \ origin .
  if (num_acc < num) then begin
		show_line2 x y (new_xy ^ 1) (new_xy ^ 2);
		f (new_xy ^ 1) (new_xy ^ 2) (next_xy  (new_xy ^ 1) (new_xy ^ 2) len  (angle +f pi +f base_ang)) num len (angle +f pi +f base_ang) base_ang  (num_acc + 1) origin;
			end
  else show_line2 x y (origin ^ 1) (origin ^ 2);



// mi sono dimenticato se il compilatore e' furbo e si calcola una sola volta angle +f etc. 


define draw_poligon_with_angle = \ x . \ y . \ num . \ len . \ angle .
	draw_poligon_ugly x y (next_xy x y len  (angle +f pi +f angle)) num len  (angle +f pi +f angle) angle 1 (x , y) ;


define draw_poligon =  \ x . \ y . \ num . \ len .
	draw_poligon_with_angle x y num len (find_alfa num) ;



define main =  begin

 initialize_graphics max_x max_y;
  draw_poligon 400 400 13 40.;

  loop 1;

end;