#load "graphics.cma";;

Graphics.open_graph "";;
Graphics.set_color 0;;

(* type point *)
type pt = float * float;;
let (creerPt : float->float->pt) = function x -> function y -> (x,y);;
let (absPt : pt->float) = function (x,y) -> x;;
let (ordPt : pt->float) = function (x,y) -> y;;

(* type carré *)
type carre = pt * float;;
let (creerCarre : pt->float->carre) = function p -> function c -> (p,c);;
let (origCarre : carre->pt) = function (p,c) -> p;;
let (coteCarre : carre->float) = function (p,c) -> c;;

(* arrondi : pour passer d'un flottant au plus proche entier *)
let round x = if x > 0. then int_of_float (x +. 0.5)
	else int_of_float (x -. 0.5);;

(* dessine un carré *)
let (traceCarre : carre->unit) = function car -> 
	let ocar = origCarre car and c = coteCarre car in
	let ax = round (absPt ocar) and ay = round (ordPt ocar) in
	Graphics.moveto ax ay ;
	Graphics.lineto (ax + round c) ay ;
	Graphics.lineto (ax + round c) (ay + round c) ;
	Graphics.lineto ax (ay + round c) ;
	Graphics.lineto ax ay;;

(* renvoie les quatres sommets (de type point) d'un carré *)
let (somCarre : carre->pt*pt*pt*pt) = function car ->
	let ocar = origCarre car and co = coteCarre car in
	let ox = absPt ocar and oy = ordPt ocar in
	let a = creerPt ox oy in
	let b = creerPt (ox +. co) oy in	
	let c = creerPt (ox +. co) (oy +. co) in
	let d = creerPt ox (oy +. co) in
	(a,b,c,d);;

(* dessine un quadrilatère donné par ses 4 sommets *)
let (dessCarre : pt*pt*pt*pt->unit) = function (a,b,c,d) -> 
	Graphics.moveto (round (absPt a)) (round (ordPt a)) ;
	Graphics.lineto (round (absPt b)) (round (ordPt b)) ;
	Graphics.lineto (round (absPt c)) (round (ordPt c)) ;
	Graphics.lineto (round (absPt d)) (round (ordPt d)) ;
	Graphics.lineto (round (absPt a)) (round (ordPt a));;

(* calcul le milieu de deux points *)
let (milieu : pt->pt->pt) = function a -> function b ->
	creerPt ((absPt a +. absPt b)/.2.) ((ordPt a +. ordPt b)/.2.);;



(* à vous de jouer... *)