diff --git a/a.out b/a.out
index 3aecaa0..3a5581b 100755
Binary files a/a.out and b/a.out differ
diff --git a/display.cmi b/display.cmi
index cac5f6a..b86063e 100644
Binary files a/display.cmi and b/display.cmi differ
diff --git a/display.cmo b/display.cmo
index eb1af1b..ac33f45 100644
Binary files a/display.cmo and b/display.cmo differ
diff --git a/display.ml b/display.ml
index 2a38f0e..f28baf8 100644
--- a/display.ml
+++ b/display.ml
@@ -1,14 +1,42 @@
 open Graphics ;;
-open Tsdl ;;
 
 Random.self_init () ;;
 
+let __width__ = 1500
+and __height__ = 1000 ;;
+
 (*
 
-ocamlfind ocamlc -linkpkg -package unix -linkpkg -package graphics -linkpkg -package tsdl -thread -package threads -linkpkg display.ml
+ocamlfind ocamlc -linkpkg -package unix -linkpkg -package graphics -thread -package threads -linkpkg display.ml
 
 *)
 
+(* ------------------------------------------------------------- *)
+(* ------------------------------------------------------------- *)
+
+type 'a dynamic = {mutable tab : 'a array ; mutable len : int ; mutable memlen : int} ;;
+
+let dyn_create i =
+  {tab = Array.make 10 i ; len = 0 ; memlen = 10} ;;
+
+let dyn_append arr elt =
+  let fct x =
+    if x < arr.len then
+      arr.tab.(x)
+    else
+      arr.tab.(0)
+  in
+  if arr.len = arr.memlen then begin
+    let newarr = Array.init (2 * arr.memlen) fct in
+    arr.memlen <- 2 * arr.memlen;
+    arr.tab <- newarr
+  end;
+  arr.tab.(arr.len) <- elt;
+  arr.len <- arr.len + 1 ;;
+
+(* ------------------------------------------------------------- *)
+(* ------------------------------------------------------------- *)
+
 let matrix_mult m1 m2 =
   let n = Array.length m1
   and p = Array.length m1.(0)
@@ -155,6 +183,92 @@ let are_faces_behind (cube : pt_3d array) =
   res.(5) <- (should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(4)) || (should_be_drawn_gr cube.(7));
   (res, res.(0) || res.(1) || res.(2) || res.(3) || res.(4) || res.(5)) ;;
 
+let are_faces_behind_rev (cube : pt_3d array) = 
+  let res = Array.make 6 false in
+  res.(0) <-
+  ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(2))) &&
+  ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(3))) && 
+    ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(1))) &&
+    ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(2))) &&
+    ((should_be_drawn_gr cube.(2)) || (should_be_drawn_gr cube.(3))) &&
+    ((should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(0))) ;
+  res.(1) <- 
+  ((should_be_drawn_gr cube.(4)) || (should_be_drawn_gr cube.(6))) &&
+  ((should_be_drawn_gr cube.(5)) || (should_be_drawn_gr cube.(7))) &&
+    ((should_be_drawn_gr cube.(4)) || (should_be_drawn_gr cube.(5))) &&
+    ((should_be_drawn_gr cube.(5)) || (should_be_drawn_gr cube.(6))) &&
+    ((should_be_drawn_gr cube.(6)) || (should_be_drawn_gr cube.(7))) &&
+    ((should_be_drawn_gr cube.(7)) || (should_be_drawn_gr cube.(4))) ;
+  res.(2) <- 
+  ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(5))) &&
+  ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(4))) &&
+    ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(1))) &&
+    ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(5))) &&
+    ((should_be_drawn_gr cube.(5)) || (should_be_drawn_gr cube.(4))) &&
+    ((should_be_drawn_gr cube.(4)) || (should_be_drawn_gr cube.(0))) ;
+  res.(3) <- 
+  ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(6))) &&
+  ((should_be_drawn_gr cube.(2)) || (should_be_drawn_gr cube.(5))) &&
+    ((should_be_drawn_gr cube.(1)) || (should_be_drawn_gr cube.(2))) &&
+    ((should_be_drawn_gr cube.(2)) || (should_be_drawn_gr cube.(6))) &&
+    ((should_be_drawn_gr cube.(6)) || (should_be_drawn_gr cube.(5))) &&
+    ((should_be_drawn_gr cube.(5)) || (should_be_drawn_gr cube.(1))) ;
+  res.(4) <- 
+  ((should_be_drawn_gr cube.(2)) || (should_be_drawn_gr cube.(7))) &&
+  ((should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(6))) &&
+    ((should_be_drawn_gr cube.(2)) || (should_be_drawn_gr cube.(3))) &&
+    ((should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(7))) &&
+    ((should_be_drawn_gr cube.(7)) || (should_be_drawn_gr cube.(6))) &&
+    ((should_be_drawn_gr cube.(6)) || (should_be_drawn_gr cube.(2))) ;
+  res.(5) <- 
+  ((should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(4))) &&
+  ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(7))) &&
+    ((should_be_drawn_gr cube.(3)) || (should_be_drawn_gr cube.(0))) &&
+    ((should_be_drawn_gr cube.(0)) || (should_be_drawn_gr cube.(4))) &&
+    ((should_be_drawn_gr cube.(4)) || (should_be_drawn_gr cube.(7))) &&
+    ((should_be_drawn_gr cube.(7)) || (should_be_drawn_gr cube.(3))) ;
+    (res, res.(0) || res.(1) || res.(2) || res.(3) || res.(4) || res.(5)) ;;
+
+let are_edges_behind (cube : pt_3d array) = 
+  let res = Array.make 6 [||] in
+  res.(0) <- [|
+    (should_be_drawn_gr cube.(0)) && (should_be_drawn_gr cube.(1));
+    (should_be_drawn_gr cube.(1)) && (should_be_drawn_gr cube.(2));
+    (should_be_drawn_gr cube.(2)) && (should_be_drawn_gr cube.(3));
+    (should_be_drawn_gr cube.(3)) && (should_be_drawn_gr cube.(0))
+  |];
+  res.(1) <- [|
+    (should_be_drawn_gr cube.(4)) && (should_be_drawn_gr cube.(5));
+    (should_be_drawn_gr cube.(5)) && (should_be_drawn_gr cube.(6));
+    (should_be_drawn_gr cube.(6)) && (should_be_drawn_gr cube.(7));
+    (should_be_drawn_gr cube.(7)) && (should_be_drawn_gr cube.(4))
+  |];
+  res.(2) <- [|
+    (should_be_drawn_gr cube.(0)) && (should_be_drawn_gr cube.(1));
+    (should_be_drawn_gr cube.(1)) && (should_be_drawn_gr cube.(5));
+    (should_be_drawn_gr cube.(5)) && (should_be_drawn_gr cube.(4));
+    (should_be_drawn_gr cube.(4)) && (should_be_drawn_gr cube.(0))
+  |];
+  res.(3) <- [|
+    (should_be_drawn_gr cube.(1)) && (should_be_drawn_gr cube.(2));
+    (should_be_drawn_gr cube.(2)) && (should_be_drawn_gr cube.(6));
+    (should_be_drawn_gr cube.(6)) && (should_be_drawn_gr cube.(5));
+    (should_be_drawn_gr cube.(5)) && (should_be_drawn_gr cube.(1))
+  |];
+  res.(4) <- [|
+    (should_be_drawn_gr cube.(2)) && (should_be_drawn_gr cube.(3));
+    (should_be_drawn_gr cube.(3)) && (should_be_drawn_gr cube.(7));
+    (should_be_drawn_gr cube.(7)) && (should_be_drawn_gr cube.(6));
+    (should_be_drawn_gr cube.(6)) && (should_be_drawn_gr cube.(2))
+  |];
+  res.(5) <- [|
+    (should_be_drawn_gr cube.(3)) && (should_be_drawn_gr cube.(0));
+    (should_be_drawn_gr cube.(0)) && (should_be_drawn_gr cube.(4));
+    (should_be_drawn_gr cube.(4)) && (should_be_drawn_gr cube.(7));
+    (should_be_drawn_gr cube.(7)) && (should_be_drawn_gr cube.(3))
+  |];
+  res ;;
+
 let draw_cube_p (cube : pt_3d array) screen_wd screen_ht fov r g b =
   let adjusted = adjust_to_camera cube in
   let (draw_faces, draw_cube) = are_faces_behind adjusted in
@@ -222,6 +336,138 @@ let draw_cube_p (cube : pt_3d array) screen_wd screen_ht fov r g b =
     done
   end ;;
 
+let draw_cube_p_rev (cube : pt_3d array) screen_wd screen_ht fov r g b =
+  let adjusted = adjust_to_camera cube in
+  let (draw_faces, draw_cube) = are_faces_behind_rev adjusted in
+  if draw_cube then begin
+    let proj = project adjusted screen_wd screen_ht fov in 
+
+    let graphed = to_graphics proj screen_wd screen_ht in 
+    set_color (rgb 192 192 192);
+
+    let distances = [|
+      max (farthest_pt cube.(0) cube.(1)) (farthest_pt cube.(2) cube.(3));
+      max (farthest_pt cube.(4) cube.(5)) (farthest_pt cube.(6) cube.(7));
+      max (farthest_pt cube.(0) cube.(1)) (farthest_pt cube.(5) cube.(4));
+      max (farthest_pt cube.(1) cube.(2)) (farthest_pt cube.(6) cube.(5));
+      max (farthest_pt cube.(2) cube.(3)) (farthest_pt cube.(7) cube.(6));
+      max (farthest_pt cube.(3) cube.(0)) (farthest_pt cube.(4) cube.(7));
+    |] in
+
+    let order = [|
+      [|graphed.(0); graphed.(1); graphed.(2); graphed.(3); graphed.(0)|];
+      [|graphed.(4); graphed.(5); graphed.(6); graphed.(7); graphed.(4)|];
+      [|graphed.(0); graphed.(1); graphed.(5); graphed.(4); graphed.(0)|];
+      [|graphed.(1); graphed.(2); graphed.(6); graphed.(5); graphed.(1)|];
+      [|graphed.(2); graphed.(3); graphed.(7); graphed.(6); graphed.(2)|];
+      [|graphed.(3); graphed.(0); graphed.(4); graphed.(7); graphed.(3)|];
+    |] in 
+
+    (* Note : edge orders must be as following :
+      7--------6
+      /|       /|
+     / |      / |
+    4--------5  |
+    |  |     |  |
+    |  3-----|--2
+    | /      | /
+    |/       |/
+    0--------1
+    *)
+
+    for i = 0 to 5 do
+      let cur_max = ref distances.(i) in
+      let idmax = ref i in
+      for j = i to 5 do
+        if distances.(j) > !cur_max then begin
+          cur_max := distances.(j);
+          idmax := j
+        end
+      done;
+      swap distances i !idmax;
+      swap order i !idmax;
+      swap draw_faces i !idmax;
+    done;
+    set_line_width 5;
+    for i = 0 to 5 do
+      if draw_faces.(i) then begin
+        let light = max (0.) (1. -. (distances.(i)) /. 7.5) in
+        let face_R = int_of_float ((float_of_int r) *. light)
+        and face_G = int_of_float ((float_of_int g) *. light)
+        and face_B = int_of_float ((float_of_int b) *. light) in
+        set_color (rgb face_R face_G face_B);
+        fill_poly order.(i);
+        set_color black;
+        draw_poly_line order.(i);
+      end
+    done
+  end ;;
+
+let draw_cube_hollow_p (cube : pt_3d array) screen_wd screen_ht fov r g b=
+  let adjusted = adjust_to_camera cube in
+  let (draw_faces, draw_cube) = are_faces_behind adjusted in
+  let draw_edges = are_edges_behind adjusted in
+  if draw_cube then begin
+    let proj = project adjusted screen_wd screen_ht fov in 
+
+    let graphed = to_graphics proj screen_wd screen_ht in 
+    set_color (rgb 192 192 192);
+
+    let distances = [|
+      max (farthest_pt cube.(0) cube.(1)) (farthest_pt cube.(2) cube.(3));
+      max (farthest_pt cube.(4) cube.(5)) (farthest_pt cube.(6) cube.(7));
+      max (farthest_pt cube.(0) cube.(1)) (farthest_pt cube.(5) cube.(4));
+      max (farthest_pt cube.(1) cube.(2)) (farthest_pt cube.(6) cube.(5));
+      max (farthest_pt cube.(2) cube.(3)) (farthest_pt cube.(7) cube.(6));
+      max (farthest_pt cube.(3) cube.(0)) (farthest_pt cube.(4) cube.(7));
+    |] in
+
+    let order = [|
+      [|graphed.(0); graphed.(1); graphed.(2); graphed.(3); graphed.(0)|];
+      [|graphed.(4); graphed.(5); graphed.(6); graphed.(7); graphed.(4)|];
+      [|graphed.(0); graphed.(1); graphed.(5); graphed.(4); graphed.(0)|];
+      [|graphed.(1); graphed.(2); graphed.(6); graphed.(5); graphed.(1)|];
+      [|graphed.(2); graphed.(3); graphed.(7); graphed.(6); graphed.(2)|];
+      [|graphed.(3); graphed.(0); graphed.(4); graphed.(7); graphed.(3)|];
+    |] in 
+
+    (* Note : edge orders must be as following :
+      7--------6
+      /|       /|
+    / |      / |
+    4--------5  |
+    |  |     |  |
+    |  3-----|--2
+    | /      | /
+    |/       |/
+    0--------1
+    *)
+
+    for i = 0 to 5 do
+      let cur_max = ref distances.(i) in
+      let idmax = ref i in
+      for j = i to 5 do
+        if distances.(j) > !cur_max then begin
+          cur_max := distances.(j);
+          idmax := j
+        end
+      done;
+      swap distances i !idmax;
+      swap order i !idmax;
+      swap draw_faces i !idmax;
+      swap draw_edges i !idmax
+    done;
+    set_line_width 5;
+    set_color (rgb r g b);
+    for i = 0 to 5 do
+      for j = 0 to 3 do
+        if draw_edges.(i).(j) then begin
+          draw_poly_line [|order.(i).(j) ; order.(i).((j+1) mod 4)|];
+        end
+      done
+    done
+  end ;;
+
 let sum_x (poly : pt_3d array) =
   let res = ref 0. in
   for i = 0 to (Array.length poly -1) do
@@ -251,46 +497,15 @@ let cube_dist (c : pt_3d array) =
   }
   in dist_from_camera mid_pt ;;
 
-let draw_multiples_cubes (cubes : pt_3d array array) screen_wd screen_ht fov = 
-  let n = Array.length cubes in
-  let new_arr = Array.make n cubes.(0) in
+let draw_multiples_cubes_colored (cubes : pt_3d array dynamic) rs gs bs screen_wd screen_ht fov render_dist = 
+  let n = cubes.len in
+
   let distances = Array.make n 0. in
+
   for i = 0 to n-1 do
-    new_arr.(i) <- cubes.(i);
-    distances.(i) <- cube_dist cubes.(i)
+    distances.(i) <- cube_dist cubes.tab.(i);
   done ;
-  for i = 0 to n-1 do
-    let cur_max = ref distances.(i) in
-    let idmax = ref i in
-    for j = i to n-1 do
-      if distances.(j) > !cur_max then begin
-        cur_max := distances.(j);
-        idmax := j
-      end
-    done;
-    swap distances i !idmax;
-    swap new_arr i !idmax;
-  done;
-  for i = 0 to n-1 do
-    draw_cube_p new_arr.(i) screen_wd screen_ht fov 192 192 192
-  done ;;
 
-let draw_multiples_cubes_colored (cubes : pt_3d array array) maxlen rs gs bs screen_wd screen_ht fov render_dist = 
-  let n = maxlen in
-
-  let new_arr = Array.make n cubes.(0)
-  and distances = Array.make n 0.
-  and reds = Array.make n 0
-  and greens = Array.make n 0
-  and blues = Array.make n 0 in
-
-  for i = 0 to n-1 do
-    new_arr.(i) <- cubes.(i);
-    distances.(i) <- cube_dist cubes.(i);
-    reds.(i) <- rs.(i);
-    greens.(i) <- gs.(i);
-    blues.(i) <- bs.(i)
-  done ;
   for i = 0 to n-1 do
     let cur_max = ref distances.(i) in
     let idmax = ref i in
@@ -301,16 +516,12 @@ let draw_multiples_cubes_colored (cubes : pt_3d array array) maxlen rs gs bs scr
       end
     done;
     swap distances i !idmax;
-    swap new_arr i !idmax;
-    swap reds i !idmax;
-    swap greens i !idmax;
-    swap blues i !idmax;
+    swap cubes.tab i !idmax;
   done;
   for i = 0 to n-1 do
-    (*Printf.printf "drawing cube (%f, %f, %f) with distance %f" new_arr.(i).(0).x new_arr.(i).(0).y new_arr.(i).(0).z distances.(i);
-    Stdlib.print_endline "...";*)
-    if distances.(i) <= (float_of_int render_dist) then
-      draw_cube_p new_arr.(i) screen_wd screen_ht fov reds.(i) greens.(i) blues.(i)
+    if distances.(i) <= (float_of_int render_dist) then begin
+      draw_cube_p cubes.tab.(i) screen_wd screen_ht fov rs.tab.(i) gs.tab.(i) bs.tab.(i)
+    end
   done ;;
 
 let create_cube x0' y0' z0' sz' =
@@ -330,69 +541,8 @@ let create_cube x0' y0' z0' sz' =
   |]
   in res ;;
 
-let cube = [|
-  {x = -1.; y = 1.; z = 1.}; 
-  {x = -2.; y = 1.; z = 1.}; 
-  {x = -2.; y = 2.; z = 1.}; 
-  {x = -1.; y = 2.; z = 1.}; 
-  {x = -1.; y = 1.; z = 2.}; 
-  {x = -2.; y = 1.; z = 2.}; 
-  {x = -2.; y = 2.; z = 2.};
-  {x = -1.; y = 2.; z = 2.}
-|] ;;
-
-let cube2 = [|
-  {x = 1.; y = 1.; z = 1.}; 
-  {x = 2.; y = 1.; z = 1.}; 
-  {x = 2.; y = 2.; z = 1.}; 
-  {x = 1.; y = 2.; z = 1.}; 
-  {x = 1.; y = 1.; z = 2.}; 
-  {x = 2.; y = 1.; z = 2.}; 
-  {x = 2.; y = 2.; z = 2.};
-  {x = 1.; y = 2.; z = 2.}
-|] ;;
-
-let cube3 = [|
-  {x = 1.; y = 1.; z = 2.}; 
-  {x = 2.; y = 1.; z = 2.}; 
-  {x = 2.; y = 2.; z = 2.}; 
-  {x = 1.; y = 2.; z = 2.}; 
-  {x = 1.; y = 1.; z = 3.}; 
-  {x = 2.; y = 1.; z = 3.}; 
-  {x = 2.; y = 2.; z = 3.};
-  {x = 1.; y = 2.; z = 3.}
-|] ;;
-
-let cube4 = [|
-  {x = 1.; y = 0.; z = 2.}; 
-  {x = 2.; y = 0.; z = 2.}; 
-  {x = 2.; y = -1.; z = 2.}; 
-  {x = 1.; y = -1. ; z = 2.}; 
-  {x = 1.; y = 0.; z = 3.}; 
-  {x = 2.; y = 0.; z = 3.}; 
-  {x = 2.; y = -1.; z = 3.};
-  {x = 1.; y = -1.; z = 3.}
-|] ;;
-
 let fov = 90 ;;
 
-let hehe () =
-  open_graph " 1500x1000" ;
-  set_window_title "3D" ;
-
-  camera_xyz.z <- 0.8;
-  for i = 0 to 488 do
-    open_graph " 1500x1000" ;
-    draw_multiples_cubes [|cube ; cube4 ; cube2 ; cube3|] 1500 1000 fov ;
-    camera_xyz.z <- camera_xyz.z -. 0.1;
-    Stdlib.print_endline "-";
-    Stdlib.print_endline "-";
-    Unix.sleepf 0.15
-  done;
-
-  Unix.sleepf 1.0;
-  close_graph () ;;
-
 (*
       7--------6
       /|       /|
@@ -470,40 +620,46 @@ let is_collision_cube (cam_coords : pt_3d) (cube : pt_3d array) =
 let is_collision (cam_coords : pt_3d) (cubes : pt_3d array array) = 
   let res = ref false in
   let n = !n_walls in
+  
+  let distances = Array.make n 0. in
+  
   for i = 0 to n-1 do
-    if not !res then
+    distances.(i) <- cube_dist cubes.(i);
+  done ;
+
+  for i = 0 to n-1 do
+    if not !res && distances.(i) < 2. then
       res := is_collision_cube cam_coords cubes.(i)
   done;
   !res ;;
+
 let convert_laby laby =
   let width = Array.length laby
   and height = Array.length laby.(0)
   and depth = Array.length laby.(0).(0) in
 
-  let cubes = Array.make (width*height*depth) [||]
-  and reds = Array.make (width*height*depth) 0
-  and greens = Array.make (width*height*depth) 0
-  and blues = Array.make (width*height*depth) 0 in
+  let cubes = dyn_create (create_cube 0 0 0 0)
+  and reds = dyn_create 0
+  and greens = dyn_create 0
+  and blues = dyn_create 0 in
 
-  let index = ref 0 in
   for w = 0 to width-1 do
     for h = 0 to height-1 do
       for d = 0 to depth-1 do
         if laby.(w).(h).(d) <> Free then begin
           (*Printf.printf "added (%d, %d, %d)" w h d;
           Stdlib.print_endline " ";*)
-          cubes.(!index) <- create_cube w h d 1;
-          reds.(!index) <- 212;
-          greens.(!index) <- 212;
-          blues.(!index) <- 212;
-          incr index
+          dyn_append cubes (create_cube w h d 1);
+          dyn_append reds 212;
+          dyn_append greens 212;
+          dyn_append blues 212;
         end
       done
     done
   done;
   (cubes, reds, greens, blues) ;;
 
-let cheesify laby =
+let cheesify (laby : tile array array array) =
   let width = Array.length laby
   and height = Array.length laby.(0)
   and depth = Array.length laby.(0).(0) in
@@ -577,7 +733,7 @@ let play laby =
     fill_poly [|(0, 0); (1500, 0); (1500, 1000); (0, 1000); (0, 0)|];
     set_color white;
 
-    draw_multiples_cubes_colored cs !n_walls rs gs bs 1500 1000 fov render_distance ;
+    draw_multiples_cubes_colored cs rs gs bs __width__ __height__ fov render_distance ;
 
     auto_synchronize true;
 
@@ -585,20 +741,7 @@ let play laby =
     Stdlib.print_endline " ";
 
     let usr_input = get1char () in 
-    move_cam cs true usr_input
-  done ;;
-
-let test1 laby =
-  cheesify laby ;
-  let (cs, rs, gs, bs) = convert_laby laby in
-  camera_xyz.z <- -. (1.5) ;
-  camera_xyz.x <- -. (float_of_int width) /. 2. ;
-  camera_xyz.y <- -. (float_of_int height) /. 2. ;
-  while true do
-    open_graph " 1500x1000";
-    draw_multiples_cubes_colored cs !n_walls rs gs bs 1500 1000 fov render_distance ;
-    camera_xyz.z <- camera_xyz.z +. 1.;
-    Unix.sleepf 1.25
+    move_cam cs.tab true usr_input
   done ;;
 
 play laby ;;
\ No newline at end of file