diff --git a/src/graphics/graphics.c b/src/graphics/graphics.c
index 2dbc729..5d7c30c 100644
--- a/src/graphics/graphics.c
+++ b/src/graphics/graphics.c
@@ -594,7 +594,7 @@ static void compute_buffers_sizes(int model_space_size_x,
                                   int model_space_size_y,
                                   int model_space_size_z,
 
-                                  int arrows_nb,
+//                                  int arrows_nb,
 
 //                                  int pref_mark_unit_space,
 //                                  int pref_style_lines_planes,
@@ -654,8 +654,7 @@ static void compute_buffers_sizes(int model_space_size_x,
 
 
 
-static bool rewrite_arrow (GLuint *arrows, int arrows_nb,
-                          long address, long weight,
+static bool rewrite_arrow (GLuint *arrows, long address, long weight,
                           long site, long x, long y, long z)
 {
     printf("write the arrow weight to %ld at (%ld, %ld, %ld, %ld)\n",\
@@ -663,15 +662,14 @@ static bool rewrite_arrow (GLuint *arrows, int arrows_nb,
     return 1; /* replaces the load of the existing arrow by the load 'weight' */
 }
 
-static bool create_arrow (GLuint *arrows, int arrows_nb,
-                          long weight, long site, long x, long y, long z)
+static bool create_arrow (GLuint *arrows, long weight, long site, long x, long y, long z)
 {
     printf("create a new arrow with weight = %ld at (%ld, %ld, %ld, %ld)\n",\
            weight, site, x, y, z);
     return 1;
 }
 
-static bool erase_arrow (GLuint *arrows, int arrows_nb, long address,
+static bool erase_arrow (GLuint *arrows, long address,
                          long site, long x, long y, long z)
 {
     if (1) printf("erase arrow at address %ld with values (%ld, %ld, %ld, %ld)\n",\
@@ -689,12 +687,6 @@ static bool erase_arrow (GLuint *arrows, int arrows_nb, long address,
     *(arrows + address + 3) = *(arrows + (arrows_nb - 1) * 5 + 3);
     *(arrows + address + 4) = *(arrows + (arrows_nb - 1) * 5 + 4);
 
-    /* *(arrows + (arrows_nb - 1) * 5 + 0) = 0;    //  est-ce bien utile ? */
-    /* *(arrows + (arrows_nb - 1) * 5 + 1) = 0; */
-    /* *(arrows + (arrows_nb - 1) * 5 + 2) = 0; */
-    /* *(arrows + (arrows_nb - 1) * 5 + 3) = 0; */
-    /* *(arrows + (arrows_nb - 1) * 5 + 4) = 0; */
-
     arrows_nb --;
     buffer_lines_size -= 14;
     buffer_lines_origin = g_realloc(buffer_lines_origin, buffer_lines_size * 2 * sizeof(GLuint) * 2);
@@ -704,8 +696,7 @@ static bool erase_arrow (GLuint *arrows, int arrows_nb, long address,
     return 1;
 }
 
-static long check_for_arrow (GLuint *arrows, int arrows_nb,
-                             long site, long x, long y, long z)
+static long check_for_arrow (GLuint *arrows, long site, long x, long y, long z)
 {
     long address = -1, f_weight = -1, f_site = -1, f_x = -1, f_y = -1, f_z = -1;
     for (int i = 0; i < arrows_nb; i++)
@@ -726,14 +717,13 @@ static long check_for_arrow (GLuint *arrows, int arrows_nb,
 }
 
 
-static bool set_arrow (GLuint *arrows, int arrows_nb,
-                       long weight, long site, long x, long y, long z)
+static bool set_arrow (GLuint *arrows, long weight, long site, long x, long y, long z)
 {
-    long address = (check_for_arrow (arrows, arrows_nb, site, x, y, z));
+    long address = (check_for_arrow (arrows, site, x, y, z));
     if (address == -1 && weight == 0) return 0;
-    if (address == -1 && weight  > 0) return create_arrow  (arrows, arrows_nb, weight, site, x, y, z);
-    if (address >=  0 && weight == 0) return erase_arrow   (arrows, arrows_nb, address, site, x, y, z);
-    if (address >=  0 && weight  > 0) return rewrite_arrow (arrows, arrows_nb, address, weight, site, x, y, z);
+    if (address == -1 && weight  > 0) return create_arrow  (arrows, weight, site, x, y, z);
+    if (address >=  0 && weight == 0) return erase_arrow   (arrows, address, site, x, y, z);
+    if (address >=  0 && weight  > 0) return rewrite_arrow (arrows, address, weight, site, x, y, z);
 
     return 0;
 }
@@ -773,7 +763,7 @@ void graphics_init_buffers(const void *gl_area)
                            model_space_size_y,
                            model_space_size_z,
 
-                           arrows_nb,
+//                           arrows_nb,
 
 //                           pref_mark_unit_space,
 //                           pref_style_lines_planes,
@@ -813,12 +803,12 @@ void graphics_init_buffers(const void *gl_area)
                       model_space_size_z * model_space_size_y, model_space_size_z,
                       arrows, arrows_nb);
 
-    set_arrow(arrows, arrows_nb, 0, 4,  3, 0, 0);
-    set_arrow(arrows, arrows_nb, 0, 5,  3, 0, 1);
-    set_arrow(arrows, arrows_nb, 0, 5,  2, 1, 1);
-    set_arrow(arrows, arrows_nb, 0, 4,  2, 1, 0);
-    set_arrow(arrows, arrows_nb, 0, 2,  2, 1, 1);
-    set_arrow(arrows, arrows_nb, 0, 3,  2, 2, 1);
+    set_arrow(arrows, 0, 4,  3, 0, 0);
+    set_arrow(arrows, 0, 5,  3, 0, 1);
+    set_arrow(arrows, 0, 5,  2, 1, 1);
+    set_arrow(arrows, 0, 4,  2, 1, 0);
+    set_arrow(arrows, 0, 2,  2, 1, 1);
+    set_arrow(arrows, 0, 3,  2, 2, 1);
 
     draw_some_arrows (buffer_lines_origin, s,
                       model_space_size_z * model_space_size_y, model_space_size_z,