<ol>
<li>Display your mesh in the viewer. </li>
-<li>Choose <b>Controls > Length 2D</b> or click <em>"Length 2D"</em>
-button in the toolbar.
+<li>Choose <b>Controls > Face Controls > Length 2D</b> or click
+<em>"Length 2D"</em> button in the toolbar.
\image html image34.png
<center><em>"Length 2D" button</em></center>