> On 30 Jan 2015, at 13:32, Zenker, Dr. Matthias <[email protected]> > wrote: > > Hi Mark, > > to my experience, the "cut and merge" feature works only for simple cases. > What you can do is to preprocess your geometry with Salomé. Load the STEP > file, modify it if needed, make a partition (that makes the duplicates go > away) and save that one as brep, then do the meshing with gmsh. > Salomé has also a meshing module, but I find that gmsh is more powerful since > it has more meshing algorithms implemented and gives better control over the > result. > > @Christophe: I don't know how the "partition" operation in Salomé works under > the hood - would it be possible to implement it in gmsh? >
It would be very useful indeed to add this operation in Gmsh ; we interfaced the Salome class "Partition_Spliter" a while back, which was supposed to do this operation. But maybe there is something more to it? Any information in this regard would be useful; it's clearly a sore point in our brep/step import. > HTH, > > Matthias > > >> -----Ursprüngliche Nachricht----- >> Von: Christophe Geuzaine [mailto:[email protected]] >> Gesendet: Donnerstag, 29. Januar 2015 19:18 >> An: Mark Smith >> Cc: [email protected] >> Betreff: Re: [Gmsh] GMSH renumbers elemntaty tags on reload >> >> >>> On 29 Jan 2015, at 13:37, Mark Smith <[email protected]> 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 <[email protected]> >>> To: Mark Smith <[email protected]> >>> Cc: "[email protected]" <[email protected]> >>> 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 <[email protected]> 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 <[email protected]> >>>> To: Mark Smith <[email protected]> >>>> Cc: "[email protected]" <[email protected]> >>>> 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 <[email protected]> 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 >>>>> [email protected] >>>>> 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 >> >> >> >> > > > > _____________________________________________________________________ > ERBE Elektromedizin GmbH > Firmensitz: 72072 Tuebingen > Geschaeftsfuehrer: Christian O. Erbe, Reiner Thede > Registergericht: Stuttgart HRB 380137 -- Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
