Create mark

 

  With this function, you can set any number of points in your distance-time diagram by a mouse click. As always, to discontinue, right click the mouse. It is suitable for positioning auxiliary  and reference points but also (possibly in combination with the line function) for setting up help and reference points but also (possibly in combination with the line function) for the set up of obstructed view perspectives or line of sight lines. Likewise, the usual  snap functions are active.