>
   - (start point selected in stretch mode):by starting a move (<kbd>m</kbd>) operation and moving the mouse the start arc angle may be changed.<br>
   - (arch center selected in stretch mode): by starting a move (<kbd>m</kbd>) operation and moving the mouse the arc radius may be changed.<br>
   If a circle is needed then use the <kbd>Ctrl-Shift-C</kbd> key combination.
   <br>A <kbd>fill=true</kbd> attribute may be given to have the shape filled with the layer fill style.
  </p>
  <img src="xschem_elemen