diff --git a/src/graphics/buffers.c b/src/graphics/buffers.c
index 1c6c3d8..7070204 100644
--- a/src/graphics/buffers.c
+++ b/src/graphics/buffers.c
@@ -344,35 +344,45 @@ static bool compute_space_3D (int space_size_x,
         }
         if (P) printf("\n");
     };
-    *(line_origin + lines_ndx) = 0; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 2; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 1; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 3; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 2; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 3; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 0; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 1; lines_ndx += 1;
+    /* *(line_origin + lines_ndx) = 0; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 2; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 1; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 3; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 2; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 3; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 0; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 1; lines_ndx += 1; */
 
-    *(line_origin + lines_ndx) = 20; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 22; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 21; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 23; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 22; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 23; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 20; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 21; lines_ndx += 1;
+    /* *(line_origin + lines_ndx) = 20; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 22; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 21; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 23; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 22; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 23; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 20; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 21; lines_ndx += 1; */
 
-    *(line_origin + lines_ndx) = 0; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 20; lines_ndx += 1;
+    for (int u = 0; u <= space_size_x * space_size_y * 2; u ++){
+        //for (int v = 0; v <= space_size_y; v ++){
+            *(line_origin + lines_ndx) = u * 2;
+            lines_ndx += 1;
+            *(line_origin + lines_ndx) = u * 2 + 1;
+            lines_ndx += 1;
+         //   v ++;
+       //}
+        //u ++;
+    }
+    /* *(line_origin + lines_ndx) = 0; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 20; lines_ndx += 1; */
 
-    *(line_origin + lines_ndx) = 1; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 21; lines_ndx += 1;
+    /* *(line_origin + lines_ndx) = 1; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 21; lines_ndx += 1; */
 
-    *(line_origin + lines_ndx) = 2; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 22; lines_ndx += 1;
+    /* *(line_origin + lines_ndx) = 2; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 22; lines_ndx += 1; */
 
-    *(line_origin + lines_ndx) = 3; lines_ndx += 1;
-    *(line_origin + lines_ndx) = 23; lines_ndx += 1;
+    /* *(line_origin + lines_ndx) = 3; lines_ndx += 1; */
+    /* *(line_origin + lines_ndx) = 23; lines_ndx += 1; */
 
     //if (S3) printf("space 3D  buffer_lines  (from-to)  ");
     printf("buffers (lines/vertex) = %d/%d    ", lines_ndx / 2, vertex_ndx / 3);
diff --git a/src/graphics/graphics.c b/src/graphics/graphics.c
index 0504ff2..f49daa9 100644
--- a/src/graphics/graphics.c
+++ b/src/graphics/graphics.c
@@ -539,8 +539,8 @@ GLubyte arrows[] = {
 
 static void get_model_data_and_user_preferences(){
 
-    model_space_size_x = 5;    //   0 < model_space_size_x
-    model_space_size_y = 1;    //   0 < model_space_size_y
+    model_space_size_x = 3;    //   0 < model_space_size_x
+    model_space_size_y = 2;    //   0 < model_space_size_y
     model_space_size_z = 1;    //   0 < model_space_size_z
     model_arrows_nb = 4; //  assert : l'emplacement des flèches est contraint
                          //  par model_space_size_x, y, z et le nombre de sites