title: Rotate existing matplotlib markers?
body: <p>I'm aware of this answer, <a href="https://stackoverflow.com/questions/23345565/is-it-possible-to-control-matplotlib-marker-orientation?noredirect=1&amp;lq=1">Is it possible to control matplotlib marker orientation?</a>, and the marker documentation, but is it possible to take an existing matplotlib marker symbol (nonregular polygon) and rotate it?</p>
  
  <p>Specifically, I would like to rotate the thin diamond symbol ("d") 90 degrees, such that its long axis is horizontal.</p>