[Gmsh] GMSH renumbers elemntaty tags on reload

Christophe Geuzaine cgeuzaine at ulg.ac.be
Fri Feb 6 15:19:40 CET 2015


> On 03 Feb 2015, at 22:43, Mark Smith <piedycat at yahoo.com> wrote:
> 
> Hi Christophe,
> The svn version (gmsh-svn-Windows64.zip 2015-02-03 02:25) seems to work for my current STEP geometry removing duplicate surfaces and on reload the elementary surface numbers do not change which is great, but it does take a long time.
> Is there any way of outputting the corrected/repaired geometry in a valid format so I can read this in with the cut and merge faces box unchecked to avoid the time consuming process again? (You have already told me not to save the STEP/BREP file as a .geo)
> 

Save "new.brep";

should do the trick


> The Salome "cut and merge" (Geometry.OCCConnectFaces = 2) doesn't crash my machine but the face numbers still change on Reload ;-(
> 
> Best regards
> Mark
> 
> 
> 
> From: Christophe Geuzaine <cgeuzaine at ulg.ac.be>
> To: Mark Smith <piedycat at yahoo.com> 
> Cc: "gmsh at geuz.org Geuzaine" <gmsh at geuz.org> 
> Sent: Friday, January 30, 2015 6:57 PM
> Subject: Re: [Gmsh] GMSH renumbers elemntaty tags on reload
> 
> 
> > On 30 Jan 2015, at 18:43, Mark Smith <piedycat at yahoo.com> wrote:
> > 
> > sorry
> > step file attached
> 
> The Salome "cut and merge" actually crashes on my machine; our internal routine seems to work (but it slow).
> 
> I've added the possibility to choose which algorithm to use - you can give it a try with tomorrow's nightly build.
> 
> 
> >  
> > From: Christophe Geuzaine <cgeuzaine at ulg.ac.be>
> > To: Mark Smith <piedycat at yahoo.com> 
> > Sent: Friday, January 30, 2015 10:20 AM
> > Subject: Re: [Gmsh] GMSH renumbers elemntaty tags on reload
> > 
> > 
> > > On 30 Jan 2015, at 10:54, Mark Smith <piedycat at yahoo.com> wrote:
> > > 
> > > Hi Christophe,
> > > Find attached a simple step file that shows the problem of face renumbering on reload, I enable the cut and merge faces to get rid of duplicate surfaces at mating solids.
> > 
> > Hi Mark - can you send the step? (You sent the solidworks part)
> > 
> > > Thanks for you time.
> > > Best regards
> > > Mark
> > >  
> > > From: Christophe Geuzaine <cgeuzaine at ulg.ac.be>
> > > To: Mark Smith <piedycat at yahoo.com> 
> > > Cc: "gmsh at geuz.org" <gmsh at geuz.org> 
> > > Sent: Thursday, January 29, 2015 6:18 PM
> > > Subject: Re: [Gmsh] GMSH renumbers elemntaty tags on reload
> > > 
> > > 
> > > > On 29 Jan 2015, at 13:37, Mark Smith <piedycat at yahoo.com> wrote:
> > > > 
> > > > Hi Christophe,
> > > > I agree that saving the cad geometry to a .geo file it is not the way to go but at least the surface numbers don't change on reload ;-)
> > > > I have some other cad geometry where I don't get this problem, which is why perhaps you haven't seen it? have you any other suggestions I could try?
> > > 
> > > Maybe the best would be for you to send an (small) step file that exhibits the problem? We could try to see where the non-deterministic numbering comes from.
> > > 
> > > > Regards
> > > > Mark
> > > >  
> > > > From: Christophe Geuzaine <cgeuzaine at ulg.ac.be>
> > > > To: Mark Smith <piedycat at yahoo.com> 
> > > > Cc: "gmsh at geuz.org" <gmsh at geuz.org> 
> > > > Sent: Thursday, January 29, 2015 11:19 AM
> > > > Subject: Re: [Gmsh] GMSH renumbers elemntaty tags on reload
> > > > 
> > > > 
> > > > > On 29 Jan 2015, at 10:45, Mark Smith <piedycat at yahoo.com> wrote:
> > > > > 
> > > > > Hi Christophe,
> > > > > Unfortunately it makes no difference ;-(
> > > > > I used cadexchanger from http://www.cadexchanger.com/ to convert the step file into a .brep file but this suffers with the same problem.
> > > > > If is do file: save as and type say file2.geo and with the GEO options box "save physical group lables"  ONLY ticked I get a file with all the points, lines line loops etc. When I lad this the element tag numbers stay fixed, ( it is relatively simple geometry consisting of volumes bounded by plane surfaces) but I cannot get the surfaces to be filled (rendered) but only crossed faces even when I set
> > > > 
> > > > Mark - Do not save your .brep/.step as a .geo! Gmsh is designed to work directly with the native files - "translating" them to .geo is only there for very specific uses or debugging purposes: the .geo CAD kernel is far too rudimentary to handle all the complexities of .step/.brep
> > > > 
> > > > 
> > > > > Geometry.SurfaceType = 2  this makes it difficult to pick surfaces to put into surface physical groups infact changing Geometry.SurfaceType to 0 1 or 2 make no difference to the way the surfaces are displayed?
> > > > > Strangely if I load in my cad geometry file Merge "file.STEP"; etc then the surfaces displayed are as expected if one changes the setting of Geometry.SurfaceType, any ideas?
> > > > > 
> > > > > Thanks in advance.
> > > > > Best regards
> > > > > Mark
> > > > > 
> > > > >  
> > > > > From: Christophe Geuzaine <cgeuzaine at ulg.ac.be>
> > > > > To: Mark Smith <piedycat at yahoo.com> 
> > > > > Cc: "gmsh at geuz.org" <gmsh at geuz.org> 
> > > > > Sent: Wednesday, January 28, 2015 7:11 PM
> > > > > Subject: Re: [Gmsh] GMSH renumbers elemntaty tags on reload
> > > > > 
> > > > > 
> > > > > > On 28 Jan 2015, at 15:36, Mark Smith <piedycat at yahoo.com> wrote:
> > > > > > 
> > > > > >  
> > > > > > Gmsh version 2.8.5
> > > > > > 
> > > > > > Hi, I load a step file generated in solidworks saved in AP203 or AP214 format and load in into GMSH using a .geo file with the following lines
> > > > > > 
> > > > > > // in gmsh options-geometry make sure the "cut and merge faces" is checked 
> > > > > > // to remove duplicate entities on import of STEP file
> > > > > > Merge "file.STEP";
> > > > > > Geometry.AutoCoherence = 1;
> > > > > > Coherence;
> > > > > > 
> > > > > > in the options:geometry I get the model to display the surface labels with their elementary tags number, if I hit reload the tag numbers change this make defining physical surfaces impossible since the surfaces shown in the surface physical groups keep changing;-(
> > > > > > I have not had this behaviour before and at this moment it is a show stopper, is there a way of preventing this behaviour?
> > > > > > 
> > > > > 
> > > > > I don't see this behavior when I do the same thing over here (note that "Geometry.AutoCoherence = 1; Coherence;" will have no effect on your STEP data)... Does adding "Delete All;" before the "Merge" command help?
> > > > > 
> > > > > 
> > > > > 
> > > > > 
> > > > > 
> > > > > > Thanks in advance
> > > > > > Mark
> > > > > 
> > > > > > 
> > > > > > 
> > > > > > _______________________________________________
> > > > > > gmsh mailing list
> > > > > > gmsh at geuz.org
> > > > > > http://www.geuz.org/mailman/listinfo/gmsh
> > > > > 
> > > > > -- 
> > > > > Prof. Christophe Geuzaine
> > > > > University of Liege, Electrical Engineering and Computer Science 
> > > > > http://www.montefiore.ulg.ac.be/~geuzaine
> > > 
> > > 
> > > 
> > > > 
> > > > 
> > > > 
> > > > > 
> > > > > 
> > > > > 
> > > > > 
> > > > > 
> > > > 
> > > > -- 
> > > > Prof. Christophe Geuzaine
> > > > University of Liege, Electrical Engineering and Computer Science 
> > > > http://www.montefiore.ulg.ac.be/~geuzaine
> > > > 
> > > > 
> > > > 
> > > > 
> > > 
> > > -- 
> > > Prof. Christophe Geuzaine
> > > University of Liege, Electrical Engineering and Computer Science 
> > > http://www.montefiore.ulg.ac.be/~geuzaine
> > > 
> > > 
> > > 
> > > 
> > > <gmshtest.SLDPRT>
> > 
> > 
> > 
> > 
> > -- 
> > Prof. Christophe Geuzaine
> > University of Liege, Electrical Engineering and Computer Science 
> > http://www.montefiore.ulg.ac.be/~geuzaine
> > 
> > 
> > 
> > 
> > <gmshtest.STEP>
> 
> 
> 
> 
> -- 
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science 
> http://www.montefiore.ulg.ac.be/~geuzaine
> 
> 
> 
> 

-- 
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science 
http://www.montefiore.ulg.ac.be/~geuzaine







More information about the gmsh mailing list