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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">When importing STL format geometry or similar, where connectivity information is not implicit in the data structure, it appears that the connectivity is reconstructed
via an octree search. This is very inefficient when surfaces with large differences in edge length are imported – we have had a recent case where an STL took 45mins to load. If the same input geometry is converted to OBJ format via an external tool, the load
time reduces to minutes.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">A generally more efficient method is to calculate the distance of each point from a location outside the point cloud bounding box and then to bubble-sort the
resulting list. Unless you are dealing with a pathological case your local search neighbourhood of identical distance points will be small and the algorithm very fast. More complex, multi-origin algorithms are also possible to counter pathological instances.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I can provide more details and sample code if you are interested.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Eugene de Villiers<o:p></o:p></span></b></p>
<p class="MsoNormal"><i><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Managing Director<o:p></o:p></span></i></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><a href="mailto:e.devilliers@engys.com">e.devilliers@engys.com</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Mob: +44 (0) 77 89748490<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Tel: +44 (0)20 32393041 (ext. 102)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Fax: +44 (0)20 33573123<o:p></o:p></span></p>
<p class="MsoNormal"><a href="http://www.engys.com/"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;text-decoration:none"><img border="0" width="136" height="30" id="Picture_x0020_1" src="cid:image001.png@01D1D6C9.FC475980" alt="logo_red-black_fonts_signature"></span></a><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Calibri",sans-serif;color:#1F497D">This message is intended only for the use of the addressee and may contain information that is privileged, confidential and exempt from disclosure under applicable
law. If the reader of this message is not the intended recipient, or the employee or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly
prohibited. If you have received this e-mail in error, please notify us immediately by return e-mail and delete this e-mail and all attachments from your system.</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
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