Anders Logg wrote: > On Mon, Jun 22, 2009 at 12:46:09PM -0600, Bartosz Sawicki wrote: >> Kent Andre wrote: >>> On ma., 2009-06-22 at 00:40 -0600, Bartosz Sawicki wrote: >>>> On 22/06/09 12:06 AM, Anders Logg wrote: >>>>> On Sun, Jun 21, 2009 at 11:36:29PM -0600, Bartosz Sawicki wrote: >>>>>> On 19/06/09 02:53 PM, kent-...@simula.no wrote: >>>>>>> When using VMTK the boundary indicators are stored as a set of arrays >>>>>>> with names >>>>>>> boundary facet cells, >>>>>>> boundary facet numbers >>>>>>> boundary indicators >>>>>>> The two first arrays are used to find the global facet numbers. >>>>>>> The function computes a mesh function based on these arrays. >>>>>>> >>>>>>> This was what Anders prefered since VMTK does not now anything >>>>>>> about the global numbering of facets in Dolfin (without linking it into >>>>>>> Dolfin). >>>>>>> >>>>>>> This is not a VMTK specific problem, but I do think VMTK is the only >>>>>>> mesh-generator >>>>>>> that let you store boundary indicators at the moment. I guess we should >>>>>>> add >>>>>>> this to NetGen as well, both Hans Petter Langtangen and Douglas Arnold >>>>>>> has >>>>>>> bugged >>>>>>> me about this the last few days. >>>>>> I'm every day user of this functionality. I use Netgen generated models, >>>>>> but also other software which add boundary indicators to existing >>>>>> meshes. Netgen supports boundary indicators quite well, both by geo >>>>>> files, and by GUI. I don't understand what you want to add? >>>>> Is it possible to set DOLFIN boundary indicators from Netgen? I didn't >>>>> know. >>>> It is definitely possible :) I don't have direct converter from Netgen >>>> vol to Dolfin xml. Most of my old models were stored in Diffpack grid >>>> format, so I'm using grid to xml converter. >>>> Netgen can export to the grid format, so this is not a big issue. >>> It is not possible to store the boundary indicators in Dolfin format >>> using Netgen, at the current time. I wrote the Netgen -> dolfin filter >>> in Netgen so I should know :). >>> >>> But it should be possible to include support for that in a similar >>> fashion as we did in VMTK. >> You are right that Netgen doesn't support Dolfin XML mesh format. But it >> doesn't mean that is not possible to use boundary indicators generated >> by Netgen in Dolfin. Converterting via Diffpack grid file preserves >> boundaries. >> >> The algoritm is simple: >> 1. Generate mesh using Netgen. >> 2. Mark boundaries indicators. >> 3. Export to Diffpack format. >> 4. Convert Diffpack to XML. >> 5. Enjoy boundary indicators in Dolfin. >> >> cheers, > > Nice, but not optimal. At some point, we need an application that can > do all of these (and more). There seem to be a couple of different > options: > > 1. Extend Netgen with full support for DOLFIN (and change the toolkit...) > 2. Extend Gmsh with full support for DOLFIN (and change the toolkit...) > 3. Extend MeshBuilder to do mesh generation (using for example Netgen) > 4. ? > > Any thoughts on these options?
Developing modeler with nice GUI and good mesher inside is huge amount of work. It would be nice to have all-in-one, but I'm afraid we don't have enough human-power. > The problem with (3) is that no one is really developing MeshBuilder, > except when we pay Kalkulo (http://simula.no/applications/kalkulo/) to > do it. I've just compiled MeshBuilder. Are there any modeler features? I could only display meshes, mark some entities, and save meshfunctions. The main problem that I see, is modeler functionality. All we need is simple and powerful modeler with nice GUI (maybe similar to Google SketchUp). Easy to say, but hard to do. I don't know any nice opensource modeler. For today, I think, all we can afford is direct converter from Netgen, or DOLFIN export implementation in Netgen. cheers, > ------------------------------------------------------------------------ > > _______________________________________________ > DOLFIN-dev mailing list > DOLFIN-dev@fenics.org > http://www.fenics.org/mailman/listinfo/dolfin-dev _______________________________________________ DOLFIN-dev mailing list DOLFIN-dev@fenics.org http://www.fenics.org/mailman/listinfo/dolfin-dev
