small addition (yellow cubes at the center)

display.ml

@@ -1047,6 +1047,17 @@ let generate_structure_1 hash mem ch_x ch_y ch_z =
             dyn_append filled {cube = create_cube ((chx+w)*chunk_size) ((chy+h)*chunk_size) ((chz+d)*chunk_size) chunk_size; red = 250; green = 128; blue = 64};
             Hashtbl.add hash (chx+w, chy+h, chz+d) filled;
           end
+          else if w = 0 && h = 0 && d = 0 then begin
+            let filled = dyn_create {cube = create_cube 0 0 0 1; red = 33; green = 33; blue = 22} in
+            for i = 0 to chunk_size -1 do
+              for j = 0 to chunk_size -1 do
+                for k = 0 to chunk_size -1 do
+                  dyn_append filled {cube = create_cube (chx*chunk_size+i) (chy*chunk_size+j) (chz*chunk_size+k) 1; red = 250; green = 250; blue = 64};
+                done
+              done
+            done;
+            Hashtbl.add hash (chx+w, chy+h, chz+d) filled;
+          end
           else begin
             Hashtbl.add hash (chx+w, chy+h, chz+d) empty;
           end;