[Gmsh] Problem creating Line Loops with the OpenCASCADE geometry kernel

[Lucas Blattner Martinho]

Dear all,

I am having trouble creating line loops while using the OpenCASCADE
geometry kernel. A line loop that seems to be well defined for  Gmsh's
native kernel is regarded as an open loop by OpenCASCADE...

A more detailed description of the problem is provided below and the .geo
files required to repeat the issue are available attached to this message.

Does anybody understand why Gmsh exhibits sjuch a behavior ? Could anybody
provide some help ?


Best regards,

Lucas Blattner
G2Elab - Laboratoire de Génie Électrique de Grenoble



Problem description :


I am working on the geometry of a complex coil in the shape of a horse
saddle (see .geo files attached to this message).

File '"Lower.geo" contain the points and lines of the geometry. These were
generated with the help of a computer program and are loaded  by the main
file "Saddle.geo" with an "Include" command.

I am trying to make line loops using the lines contained  in the
aforementioned file to proceed creating surfaces and volumes. The lines ids
are stored in vectors such as Lower_Line2[], Lower_InputLine[] and so on,
all of which are defined in "Lower.geo".

I am particularly interested in generating a thin volume with the aid of
the "ThruSections"  function provided by OpenCASCADE. The first step is the
creation of the line loops required by this function..

That  said, I created a line loop  in the main file "Saddle.geo". The loop
seem to be OK, that is, it  is  closed and is  created without console
errors or warnings. This can be verified by taking a look at the physical
regions "myLoop", which correspond to the same list of lines composing the
loop.

However, loading "Saddle.geo" after uncommenting the first line of the code
(to enable the OpenCASCADE functions) results in the following error :


*Error   : Line Loop is not closedError   : 'C:\xxxxxx\saddle.geo', line
6 : Could not add line loop*

This error makes it impossible to continue using ThruSections. Since the
line loop seems to be correctly defined, I believe that it could be caused
by a bug....
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