[Gmsh] importing .step files with multiple parts whose surfacestouch

Zenker, Dr. Matthias Matthias.Zenker at erbe-med.com
Mon Apr 4 12:58:01 CEST 2011


Hi Brent and Mark,

at the moment, I am still working on my processor for the 2D mesh. But as soon as the problem I have with GiD (crash at geometry import in at least one case) is solved, I will stop that work and use GiD. It can collapse surfaces and is not expensive, so it may be worthwhile to try it wioth a one-month evaluation license.

Sorry, gmsh team - gmsh is a very nice tool, and I like it, but it does not offer a real solution to this "3D geometries with double surfaces" problem.

If I manage to develop my 2D mesh processor to a point where it is useful in any way, I will post it here. 

Matthias



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ERBE Elektromedizin GmbH
Dr.rer.nat. Matthias Zenker
Dipl. Phys.
Grundlagenentwicklung / Fundamental Development
Waldhoernlestrasse 17
72072 Tuebingen
Germany
Phone + 49 (0) 7071 755 - 226
Fax + 49 (0) 7071 755 - 5226
E-Mail: <mailto:Matthias.Zenker at erbe-med.com>
URL: http://www.ERBE-med.com
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-----Ursprüngliche Nachricht-----
Von: Mark van Doesburg [mailto:mark.van.doesburg at technolution.nl] 
Gesendet: Montag, 4. April 2011 09:31
An: gmsh at geuz.org; Brent.Vandevender at pnl.gov
Cc: Zenker, Dr. Matthias
Betreff: Re: [Gmsh] importing .step files with multiple parts whose surfacestouch

Hello Brent,

The code I've written was not intended for plane surfaces only. I many cases it works on spheres and cylinders as well. Unfortunately the OCC code does not always find all intersections and many special cases are not handled correctly.

I understood that netgen had something that worked, but apparently (Matthias's reply) it does not.

I intend to write something when I can find the time, but that might take a while. I'll try to avoid writing something from scratch, but I doubt I'll have another look at OCC. Currently CGAL looks the most promising.

Mark van Doesburg.

"Vandevender, Brent A" <Brent.Vandevender at pnl.gov> wrote:

	Thank you for your reply Matthias.  I specifically had you and Mark van Doesburg in mind when I posed the question.  I have followed your posts in the archives and hoped that there was some progress.  I have only recently realized the gravity of my problem and start to appreciate the astronomically high price of the commercial electricity and magnetism FEM package I am trying not to have to buy (Maxwell3D).  It seems I will take some effort to solve the problem myself, as you have.  The best solution, I think,  is to fix the 2D surface meshes created by gmsh with a separate self-written code and re-import to gmsh as you describe in option 2.  I can imagine how the algorithm will work, but also that it will take the age of the universe to complete for a realistic geometry.  My intention was to be a mere consumer of finite-element methods, and I don't know where I will find the time to become a producer.