0     align-&gt;save_rigid_alignment_vals();
<a name="l00551"></a>00551 
<a name="l00552"></a>00552     <span class="comment">// We require at least 3 correspondences to fully describe a 3D alignment</span>
<a name="l00553"></a>00553     <span class="keywordflow">if</span>(npts &lt; 3) <span class="keywordflow">return</span>;
<a name="l00554"></a>00554 
<a name="l00555"></a>00555     <span class="comment">// Save the initial alignment in the event we need to revert to it</span>
<a name="l00556"></a>00556   