<html><body><div style="font-family: arial,helvetica,sans-serif; font-size: 12pt; color: #000000"><div>Hello,<br><br></div><div>thanks for your immediate response. Yet adding the compound constraint to surfaces 21 and 22 doesn't solve the problem. The virtual topology is still ignored. </div><div><br data-mce-bogus="1"></div><div> Is that because I didn't <!--StartFragment-->"redefine the volume in terms of the new surfaces"? How would I do this? As I understand your concept of virtual topology, there aren't any new surfaces at all, just meshing constraints. So what should I do to redefine the volume?<!--EndFragment--> </div><div><br data-mce-bogus="1"></div><div>Furthermore, I have to set a rather small element size in order to avoid negative jacobians.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>How about imposing local mesh refinement in areas with invalid elements? That might be a way to automatically resolve such problems in a smarter way than just global refinement.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div><div><img src="cid:aebd869d91d2069857bc6acb2a5e9c153715fa3f@zimbra" data-mce-src="cid:aebd869d91d2069857bc6acb2a5e9c153715fa3f@zimbra" width="743" height="439"></div><div> <!--StartFragment--> </div>Best regards, Martin Kraska</div><div><br><span id="zwchr" data-marker="__DIVIDER__">----- Am 22. Jul 2019 um 22:42 schrieb Christophe Geuzaine <cgeuzaine@uliege.be>:<br></span></div><div data-marker="__QUOTED_TEXT__"><blockquote style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;" data-mce-style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><blockquote style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;" data-mce-style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;">On 22 Jul 2019, at 21:47, Martin Kraska <martin.kraska@th-brandenburg.de> wrote:<br> <br> Hello,<br> <br> in the attached script I try to mesh a step part using virtual topology (trying<br> to update the example<br> https://github.com/mkraska/CalculiX-Examples/tree/master/CAD/OnshapeTutorial )<br> I see that I have to use a new syntax for virtual topology but otherwise did not<br> make any changes compared to gmsh 3.0.3 which I tried last.<br> <br> In gmsh 4.3.0 I get a boundary mesh issue.<br> In 4.4.0 the virtual topology is just ignored but the part is meshed.<br> in the git version of today (2019-07-22) I get a slightly different boundary<br> mesh issue.<br> <br> Did I miss some settings? Or is the part just too nasty?</blockquote><br> <br> You forgot to set:<br> <br> Compound Surface {21};<br> Compound Surface {22};<br> <br> With these the first order mesh looks OK.<br> <br> Note that the 2nd order mesh will not work - this is currently expected with<br> Mesh.CompoundClassify=1 (the default), as elements are reclassified across the<br> boundaries.<br> <br> We will improve this in the future. In the meantime, you can set<br> Mesh.CompoundClassify=0; but you will need to redefine the volume in terms of<br> the new surfaces. We haven't decided yet what the best/most natural workflow<br> should be in that case. Any feedback is welcome!<br> <br> Christophe<br> <br> <br> <br><blockquote style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;" data-mce-style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><br> Thanks for any advice, Martin Kraska<br> <vt.zip>_______________________________________________<br> gmsh mailing list<br> gmsh@onelab.info<br> http://onelab.info/mailman/listinfo/gmsh</blockquote><br> <br> —<br> Prof. Christophe Geuzaine<br> University of Liege, Electrical Engineering and Computer Science<br> http://www.montefiore.ulg.ac.be/~geuzaine<br><br></blockquote></div></div></body></html>