[Gmsh] Negative area with MEDIT mesh format 2D.

[Geordie McBain]

2010/6/2 Philippe Miron <philippe.miron at polymtl.ca>:
> I try to define the Line Loops in a different order but still getting node
> number in the clockwise direction..
> I think I'll just do a postprocessing script to fix all triangles and edges
> elements.

Really?  I tried the following two geometry files for a simple
triangular Plane Surface, with the characteristic length set large
enough so that the (MEDIT) mesh ends up with a single Triangle
element.
Both have the Points numbered anticlockwise: 1, 2, 3.  In positive.geo
I join them anticlockwise, in negative.geo clockwise, into Lines, and
I get the expected correct orientation in the MEDIT: positive.mesh has
its triangle 2 3 1 and negative 2 1 3.

I run these with, e.g.,

$ gmsh -2 -format mesh -string "Mesh.SaveElementTagType=2;" positive.geo
-------------- next part --------------
A non-text attachment was scrubbed...
Name: triangle.geo
Type: application/octet-stream
Size: 78 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20100602/3945bc26/attachment.geo>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: positive.geo
Type: application/octet-stream
Size: 156 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20100602/3945bc26/attachment-0001.geo>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: negative.geo
Type: application/octet-stream
Size: 155 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20100602/3945bc26/attachment-0002.geo>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: positive.mesh
Type: model/mesh
Size: 322 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20100602/3945bc26/attachment.mesh>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: negative.mesh
Type: model/mesh
Size: 322 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20100602/3945bc26/attachment-0001.mesh>