anchor.diff:                 end,
                  [], Trace),
       Nodes = lists:reverse(NodesR),
  -    DrawTrace = time_delta(Trace),
  +    DrawTrace = DeltaFun(Trace),
   
       EndTime =  element(2, lists:last(DrawTrace)),
   
  
positive.code:               "  \\draw[color=red!50!black,->] (-2cm, 0.5)"
                "  -- (-1.5cm, 0.5) node[anchor=west] {global send};~n", []),
  
      draw_messages(File, Nodes, ScaleX, DrawTrace),
  
      io:format(
        File,
  
negative.code:       fun(I) ->
                io:format(File,
                "  \\draw[color=gray, very thin] (~pcm, 0.5)"
                "  node[above] {~p" ++ ?IIF(HaveRealTime, "$\\mu$s", "") ++ "} --"
                " (~p, -~p);~n",
                [I*TicsFreq/ScaleX,
                 I*TicsFreq,
  