<polygon id="0" faceup="true" z="0">
  <vertex id="4" x="-50.0" y="50.0" is_crease="false"></vertex>
  <vertex id="3" x="50.0" y="50.0" is_crease="false"></vertex>
  <vertex id="2" x="50.0" y="-50.0" is_crease="false"></vertex>
  <vertex id="1" x="-50.0" y="-50.0" is_crease="false"></vertex>
</polygon>
<caption>square</caption>
