<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.E-MailFormatvorlage17
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.E-MailFormatvorlage18
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 70.85pt 2.0cm 70.85pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="DE" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span style="color:#1F497D">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">I want to add some information.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Yes, for the test case I could simply switch to “Plane Surface” and everything is working. But in reality, my models also consist on non-planar surfaces. I added another test as an attachment to
this mail.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">I found that if I increment the Line Loop and Surface numbers by 2 instead of 1, e.g. from the attached example:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Line Loop(1) = {10,2,11,3};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Surface(1) = {1};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Transfinite Surface(1) = {};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Recombine Surface(1) = 60.0;<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Physical Surface(1) = {1};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Line Loop(3) = {12,4,13,5};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Surface(3) = {3};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Transfinite Surface(3) = {};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Recombine Surface(3) = 60.0;<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Physical Surface(3) = {3};<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">no errors occur as well. This matches the error message. It seems that with the OpenCASCADE Factory, additional line loops are created internally. Changing this in my code would be possible but work
I would rather avoid.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Can someone explain to me what where the different treatment of “Plane Surface” and “Surface” with respect to the line loops comes from? The
<a href="http://gmsh.info/doc/texinfo/gmsh.html#Surfaces">documentation</a> says “Surface” is a “surface filling”. What does that mean exactly?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Best regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Martin</span><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DE">Von:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";mso-fareast-language:DE"> gmsh [mailto:gmsh-bounces@ace20.montefiore.ulg.ac.be]
<b>Im Auftrag von </b>Martin.Raedel@dlr.de<br>
<b>Gesendet:</b> Sonntag, 8. Juli 2018 17:01<br>
<b>An:</b> gmsh@onelab.info<br>
<b>Betreff:</b> [Gmsh] Error when switching from Built-In to OpenCascade Factory<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I just recently tried to switch from the built-in Factory to OpenCascade to use Boolean operations.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">However, all of my tests involving more than one surface crash after the switch with the same error:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">OpenCascade wire or line loop with tag 2 already exists<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The same error occurs for all other surfaces except the first.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I added a simple brick geometry example. In case I comment out “SetFactory("OpenCASCADE"); “ everything works fine. If I use the line, the errors occur.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Can someone please point out what causes these errors and how I can fix them?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:DE">Best regards<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:DE">Martin Rädel<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:dimgray;mso-fareast-language:DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:dimgray;mso-fareast-language:DE">————————————————————————</span><span style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE">Deutsches Zentrum für Luft- und Raumfahrt</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE"> e.V.
(DLR)</span><span style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:16.0pt"><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE">German Aerospace Center</span><span lang="EN-US" style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:16.0pt"><span lang="EN-US" style="font-size:8.5pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE">Institute of Composite Structures and Adaptive Systems | Structural Mechanics | Lilienthalplatz
7 | 38108 Braunschweig | Germany</span><span lang="EN-US" style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:dimgray;mso-fareast-language:DE"> </span><span lang="EN-US" style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:dimgray;mso-fareast-language:DE">Dipl.-Ing. </span><b><span lang="EN-US" style="font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE">Martin Rädel</span></b><span lang="EN-US" style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:16.0pt"><span lang="EN-US" style="font-size:8.5pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:DE">Telephone +49 (0)531 295-2048 | Telefax +49 (0)531 295-2232 |</span><span lang="EN-US" style="font-size:8.5pt;font-family:"Arial","sans-serif";mso-fareast-language:DE"> <a href="mailto:martin.raedel@dlr.de"><span style="color:#005AA5">martin.raedel@dlr.de</span></a></span><span lang="EN-US" style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:16.0pt"><span lang="EN-US" style="font-size:8.5pt;font-family:"Arial","sans-serif";mso-fareast-language:DE"><a href="http://www.dlr.de/"><span style="color:#005AA5">www.DLR.de</span></a></span><span style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</body>
</html>