diff --git a/main.cmi b/main.cmi
index a70d639..21f9406 100644
Binary files a/main.cmi and b/main.cmi differ
diff --git a/main.cmx b/main.cmx
index 3827cda..3099830 100644
Binary files a/main.cmx and b/main.cmx differ
diff --git a/main.ml b/main.ml
index 97d6bc4..eb4cfb2 100644
--- a/main.ml
+++ b/main.ml
@@ -17,7 +17,7 @@ and __height__ = 800 ;;
 
 let __istr__ = " 1200x800" ;;
 
-let univ_dt = 0.003 ;;
+let univ_dt = 0.01 ;;
 
 let _camx_ = ref 0
 and _camy_ = ref 0 ;;
@@ -76,6 +76,7 @@ type ball = {
   v : pt_2d ;
   a : pt_2d ;
   fres : pt_2d ;
+  fres_0 : pt_2d ;
 } ;;
 
 (* --- *)
@@ -436,8 +437,11 @@ let remove_dead_destr (destr : polygon dynamic) (cand : int list) =
   in aux cand ;;
 
 let update_ball_data (b : ball) (id : int) (balls : ball array) (polys : polygon dynamic) (destr : polygon dynamic) (spheres : sphere dynamic) (flips : flipper dynamic) (dt : float) =
-  b.fres.x <- 0. ;
-  b.fres.y <- 0. ;
+  b.fres.x <- b.fres_0.x ;
+  b.fres.y <- b.fres_0.y ;
+
+  b.fres_0.x <- 0. ;
+  b.fres_0.y <- 0. ;
 
   let destr_remove = ref [] in
 
@@ -573,6 +577,9 @@ let update_ball_data (b : ball) (id : int) (balls : ball array) (polys : polygon
         let reaction_force_2 = vect_mult_2D proj_n (univ_g *. b.mass *. scal) in
         b.fres.x <- b.fres.x +. reaction_force_2.x *. 1.1 ;
         b.fres.y <- b.fres.y +. reaction_force_2.y *. 1.1 ;
+        (* apply forces to collisionned marble *)
+        balls.(s).fres.x <- balls.(s).fres.x -. reaction_force_2.x *. 1.1 ;
+        balls.(s).fres.y <- balls.(s).fres.y -. reaction_force_2.y *. 1.1 ;
       end;
 
       (* change velocity according to angle *)
@@ -583,6 +590,14 @@ let update_ball_data (b : ball) (id : int) (balls : ball array) (polys : polygon
 
       b.v.x <- symmetric.x ;
       b.v.y <- symmetric.y ;
+      (* apply forces to collisionned marble *)
+      let rc_theta = balls.(s).radius /. (vect_norm_2D (vect_diff_2D balls.(s).xy b.xy)) in
+      let rc_intersection = (vect_convexf balls.(s).xy b.xy rc_theta) in
+      let rc_director = vect_normal_2D rc_intersection (vect_sum_2D rc_intersection proj_n) in
+      let rc_symmetric = vect_symmetry balls.(s).v {x = 0. ; y = 0.} rc_director in
+
+      balls.(s).v.x <- rc_symmetric.x ;
+      balls.(s).v.y <- rc_symmetric.y ;
     end
   done ;
 
@@ -885,6 +900,7 @@ let create_ball (r : float) (x0 : int) (y0 : int) (m : float) (red : int) (green
     v = {x = 0. ; y = 0.} ;
     a = {x = 0. ; y = 0.} ;
     fres = {x = 0. ; y = 0.} ;
+    fres_0 = {x = 0. ; y = 0.} ;
   } ;;
 
 let create_polygon ?showScore:(shsc=true) (arr : (int * int) array) (rest : float) (pts : int) (red : int) (green : int) (blue : int) =
@@ -1022,7 +1038,7 @@ let simulate (data : polygon dynamic) (destructible : polygon dynamic) (dats : s
   open_graph __istr__ ;
   set_window_title "WAH" ;
 
-  let pinballs = generate_pinballs 8 10.0 600 800 0.15 255 255 0 in
+  let pinballs = generate_pinballs 8 10.0 600 1000 0.15 255 255 0 in
   let stime = Unix.gettimeofday () in
   let ctime = ref (Unix.gettimeofday ()) in
 
@@ -1080,10 +1096,13 @@ let flippers = dyn_create default_flipper ;;
 dyn_add polygons (create_polygon [|(700, -20); (500, -20); (500, 1); (700, 1)|] 0. 0 255 32 32) ;;
 
 (* upper part *)
-dyn_add polygons (create_polygon [|(500, -200); (700, -200); (700, -250); (500, -250)|] 0. 0 32 32 32) ;;
-dyn_add polygons (create_polygon [|(500, 800); (500, 1100); (450, 1100); (450, 800)|] 0. 0 32 32 32) ;;
-dyn_add polygons (create_polygon [|(700, 800); (700, 1100); (750, 1100); (750, 800)|] 0. 0 32 32 32) ;;
-dyn_add polygons (create_polygon [|(450, 1100); (750, 1100); (750, 1150); (450, 1150)|] 0. 0 32 32 32) ;;
+dyn_add polygons (create_polygon [|(500, -200); (700, -200); (700, -250); (500, -250)|] 1. 0 32 32 32) ;;
+dyn_add polygons (create_polygon [|(500, 800); (500, 1100); (450, 1100); (450, 800)|] 1. 0 32 32 32) ;;
+dyn_add polygons (create_polygon [|(700, 800); (700, 1100); (750, 1100); (750, 800)|] 1. 0 32 32 32) ;;
+dyn_add polygons (create_polygon [|(450, 1100); (750, 1100); (750, 1150); (450, 1150)|] 1. 0 32 32 32) ;;
+
+(* TEST *)
+(* dyn_add polygons (create_polygon [|(500, 800); (700, 800); (700, 850); (500, 850)|] 1. 0 32 32 32) ;; *)
 
 (* outer walls *)
 dyn_add polygons (create_polygon [|(0, -250); (500, -250); (500, 20); (0, 20)|] 1. 0 32 32 32) ;;
diff --git a/main.o b/main.o
index 7aeda1a..2e47b27 100644
Binary files a/main.o and b/main.o differ
diff --git a/pinball b/pinball
index 7a50c01..56535c1 100755
Binary files a/pinball and b/pinball differ