[Gmsh] normals (again)

[John Borchardt]

Well I'll be darned if I know how THAT got checked!  Thanks,
everything is behaving as expected now!


On Fri, Feb 15, 2008 at 12:11 PM, Christophe Geuzaine
<cgeuzaine at ulg.ac.be> wrote:
>
> John Borchardt wrote:
>  > Hi, please see attached screenshot.  The geometry normal is in red and
>  > the mesh normals are in green -- and they are pointing in opposite
>  > directions as far as I can tell.
>  >
>  > The .geo file that produced this is:
>  >
>  > Point(1) = {0,0,0,0.1};
>  > Point(2) = {1,0,0,0.1};
>  > Point(3) = {0,1,0,0.1};
>  > Line(1) = {1,2};
>  > Line(2) = {2,3};
>  > Line(3) = {3,1};
>  > Line Loop(4) = {1,2,3};
>  > Plane Surface(5) = {4};
>  >
>  > The console output is:
>  >
>  > Info    : -------------------------------------------------------
>  > Info    : Gmsh version   : 2.0.8
>  > Info    : Build OS       : Linux
>  > Info    : Build options  : GSL NETGEN JPEG PNG ZLIB MATHEVAL ANN
>  > Info    : Build date     : Sat Aug 11 17:09:17 GMT 2007
>  > Info    : Build host     : yellow
>  > Info    : Packager       : buildd
>  > Info    : Home directory : /home/john/
>  > Info    : Launch date    : Fri Feb 15 11:54:09 2008
>  > Info    : Command line   : gmsh plate.geo
>  > Info    : -------------------------------------------------------
>  > Info    : Reading 'plate.geo'
>  > Info    : Read 'plate.geo'
>  > Info    : Meshing 1D...
>  > Info    : Meshing curve 1
>  > Info    : Meshing curve 2
>  > Info    : Meshing curve 3
>  > Info    : Mesh 1D complete (0 s)
>  > Info    : Mesh
>  > Info    : Meshing 2D...
>  > Info    : Meshing surface 5 (Plane, MeshAdapt+Delaunay)
>  > Info    : Mesh 2D complete (0.004 s)
>  > Info    : Mesh
>  > Info    : 21 vertices 40 elements
>  > Info    : Meshing 3D...
>  > Info    : Mesh 3D complete (0 s)
>  > Info    : Mesh
>  > Info    : 21 vertices 40 elements
>  > Info    : Reading 'plate.geo'
>  > Info    : Read 'plate.geo'
>  > Info    : Meshing 1D...
>  > Info    : Meshing curve 1
>  > Info    : Meshing curve 2
>  > Info    : Meshing curve 3
>  > Info    : Mesh 1D complete (0.004001 s)
>  > Info    : Mesh
>  > Info    : Meshing 2D...
>  > Info    : Meshing surface 5 (Plane, MeshAdapt+Delaunay)
>  > Info    : Mesh 2D complete (0 s)
>  > Info    : Mesh
>  > Info    : 22 vertices 42 elements
>  >
>  >
>  > Any ideas what's going wrong?  I am using Ubuntu 7.10 x86-64 and I
>
>
>  You wouldn't have the "Reverse all normals" option checked in
>  Tools->Options->Mesh->Light, by any chance?
>
>
>
>
>
>
>
>
>
>  > installed via apt-get I believe.  Thanks!
>  >
>  >
>  > --John
>  >
>  >
>  >
>  >
>  >
>  >
>  > On Fri, Feb 15, 2008 at 11:32 AM, Christophe Geuzaine
>  > <cgeuzaine at ulg.ac.be> wrote:
>  >> John Borchardt wrote:
>  >>  > Sorry I am looking in the manual and list archives and I still don't
>  >>  > understand...
>  >>  >
>  >>  > Can you tell me if the default behaviour of gmsh is such that mesh
>  >>  > element normals are opposite of the surface normals?  Am using version
>  >>  > 2.0.8.
>  >>  >
>  >>  > E.g., when I mesh the following .geo, the element normals are opposite
>  >>  > of the surface normal...
>  >>
>  >>
>  >>  I cannot reproduce this on my machine...
>  >>
>  >>
>  >>
>  >>  >
>  >>  >
>  >>  > Point(1) = {0,0,0,0.1};
>  >>  > Point(2) = {1,0,0,0.1};
>  >>  > Point(3) = {0,1,0,0.1};
>  >>  > Line(1) = {1,2};
>  >>  > Line(2) = {2,3};
>  >>  > Line(3) = {3,1};
>  >>  > Line Loop(4) = {1,2,3};
>  >>  > Plane Surface(5) = {4};
>  >>  >
>  >>  >
>  >>  >
>  >>  > Thanks,
>  >>  >
>  >>  >
>  >>  > --John
>  >>  >
>  >>  > _______________________________________________
>  >>  > gmsh mailing list
>  >>  > gmsh at geuz.org
>  >>  > http://www.geuz.org/mailman/listinfo/gmsh
>  >>  >
>  >>  >
>  >>
>  >>
>  >>  --
>  >>  Prof. Christophe Geuzaine
>  >>  University of Liege, Electrical Engineering and Computer Science
>  >>  http://www.montefiore.ulg.ac.be/~geuzaine
>  >>
>  >>
>  >> ------------------------------------------------------------------------
>  >>
>  >>
>  >> ------------------------------------------------------------------------
>
>
> >>
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>
>
>  --
>  Prof. Christophe Geuzaine
>  University of Liege, Electrical Engineering and Computer Science
>  http://www.montefiore.ulg.ac.be/~geuzaine
>