[MOAB-dev] One more question: TRI3/6

[Wollaber, Allan B.]

I've noticed that the vertices coming back from a TRI3 or TRI6 element
appear to be numbered in the wrong direction (clockwise instead of
counterclockwise). For instance, for a TRI3, I get (using a one-based
indexing):

[NTmesh]...Global coordinate for each mesh vertex in cm
[NTmesh]...     1 X,Y,Z =  0.000000000E+00, 0.000000000E+00,
[NTmesh]...     2 X,Y,Z =  1.000000000E+00, 0.000000000E+00,
[NTmesh]...     3 X,Y,Z =  0.000000000E+00, 1.000000000E+00
[NTmesh]...Finite element connectivity listing
[NTmesh]...     1 Links      1      3      2

which corresponds to:
2
|  \
|    \
|      \
1-------3

And for a TRI6 I get
[NTmesh]...Global coordinate for each mesh vertex in cm
[NTmesh]...     1 X,Y,Z =  0.000000000E+00, 1.000000000E+00,
[NTmesh]...     2 X,Y,Z =  0.000000000E+00, 0.000000000E+00,
[NTmesh]...     3 X,Y,Z =  0.000000000E+00, 5.000000000E-01,
[NTmesh]...     4 X,Y,Z =  1.000000000E+00, 0.000000000E+00,
[NTmesh]...     5 X,Y,Z =  5.000000000E-01, 5.000000000E-01,
[NTmesh]...     6 X,Y,Z =  5.000000000E-01, 0.000000000E+00,
[NTmesh]...Finite element connectivity listing
[NTmesh]...     1 Links      2      1      4      3      5      6

which corresponds to:

2
|  \
4    5
|      \
1----6---3

This seems to be against the MBCN convention, which assumes
counterclockwise numbering. Is this a bug, or am I doing something
wrong?  The code I am using to get the connectivity is the same as the
snippet I sent several emails ago.

Thanks,
- Allan
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