[Gmsh] using gui

[Magdalena Stolarska]

Thanks to both of you for your response.

To Joe Koski:  Actually, you can build the whole geometry using the GUI.
What you do is the following.  When you open up gmsh, you can pick between
geometry, mesh, solver, and post-processing.  To create a geometry, you
choose 'geometry' (which seems to be the default when you open gmsh), and
then to add a new entity such as a point or line or volume, etc, you pick
'Elementary', then 'Add', then 'New'.  After that you have a whole list of
geometrical entities to choose from.  Setting up most of the new entities
is pretty intuitive.  What was unclear to me is that after you pick the
lines bounding your plane surface you have to press 'q' (for quit, I
guess), and this is how gmsh knows that you are done setting up the line
loop for a plane surface.  Once you are done setting up your geometry, you
can save it as a *.geo file, which means that gmsh generates the script
that you mentioned below.  I just started playing around with the gui
today, so this is basically all I know of its features.  However, it is
already clear to me how useful it is, not to mention _so_ much easier than
writing out your own geometry file, especially for complicated geometries.

-MS


On Wed, 26 May 2004, Joe Koski wrote:

> As an outside observer, I think I understand her question. It is one that I
> have wondered about too. When you build an object in GMSH, it appears to me
> that you always start with an external script file that you import to
> describe some grid points and, then, step-by-step build the geometry. This
> scripting is outside the GUI in an editor. You keep adding to the script and
> rerunning it as you go. Once that's done you can rotate, inspect, etc.
>
> Only the meshing part, after the geometry is built, appears (to me) to be
> truly interactive within the GUI.
>
> Is this interpretation correct? My background is with Patran, and there you
> could always see the points, surfaces, volumes, nodes and elements appear on
> the screen as you built the mesh. (There are problems with that approach
> too. Changes can get really messy.) It appears that in GMSH need you to
> describe the geometry with a separate script file before you start.
>
> Please correct me if I misinterpreted.
>
> Joe Koski
>
> on 5/26/04 6:02 PM, Christophe Geuzaine at geuzaine at acm.caltech.edu wrote:
>
> > Magdalena Stolarska wrote:
> >
> >> Hi.  I am wondering how one creates plane surfaces and volumes using the
> >> gui.  I have managed on setting up the points and creating lines, but when
> >> I try to use the "Plane Surface" or "Volume" option my intuition is not
> >> correct, and as far as I can see, there is little documentation about the
> >> gui on the web.
> >>
> >
> > For surfaces, you have to select the exterior boundary (click on the
> > boundary lines) first, than select any holes (again by clicking on the
> > boundaries of the holes). Same for volumes, except you have to select
> > the boundary surfaces.
> >
> > Note that Gmsh's next version will have a much improved entity selection
> > gui (with multiple "undo" capability)... If you want to give it a try,
> > you can download the nightly archive from http://geuz.org/gmsh/src/
> >
> > Cheers,
> >
> > Christophe
>
>