vtkWedge confusion

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vtkWedge confusion

Jeff Lee
Hi,
I am confused about the vtkWedge celltype -  in the manual, and current
documentation, the node ordering is such that the bottom tri points away
from the top tri (using the right-hand rule).  Previous code
documentation suggests that the bottom tri points into the top tri (like
a hex).  I did a test where I placed a tet next to a wedge(using the
current definition of node ordering) in a vtkUnstructuredGrid, and cut a
plane section through both cells.  The resulting contour pieces had
normals facing in opposite directions (the wedge pieces were pointing
opposite to the tet pieces).  When I make the base of the wedge point
into the top tri, all the contour pieces point in the same direction.  
Based on my assumption that the contouring algorithm is designed to make
the orientation of all output tris consistent , is it correct to
conclude that the vtkWedge cell type is documented incorrectly, and that
the current picture in the manuals should have nodes 1 and 2 swapped as
well as 4 and 5 swapped?
Regards,
Jeff
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Re: [vtk-developers] vtkWedge confusion

Mathieu Malaterre-2
is it correct to
> conclude that the vtkWedge cell type is documented incorrectly, and that
> the current picture in the manuals should have nodes 1 and 2 swapped as
> well as 4 and 5 swapped?

Correct. This will be updated in the next version of the book.
     2
    /\
   /  \
  /    \
0-----1\
  \     /\5
   \   /  \
    \ /    \
     3------ 4

Mathieu
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