[vtkusers] question about vtkMeshQuality.cxx

[Philippe P. Pebay]

Hi

I was looking at using vtkMeshQuality for some paper results, but it 
seems that the name of this class is too generic, because:
1. it only addresses tetrahedral meshes
2. in the case of tetrahedral meshes, there are many quality measures 
that can be used, but this class only provides the "radius-ratio" 
(normalized circumradius / inradius).

I haven't seen any other quality metrics in VTK; would anyone mind if we 
revise vtkMeshQuality to compute various quality measures on several 
different types of cells ?  We would like to compute the following 
quality measures:
1. tetrahedral meshes: radius-ratio, aspect-ratio, shape measures 
(Frobenius-like), etc.
2. hexahedral meshes
3. triangular and quadrilateral elements: various measures in the 
literature.

Also, I noticed that the Execute method in vtkMeshQuality.cxx declares 
p# and dp# (#= 1,2,3,4) as double arrays, and then copies p's into dp's. 
But it appears that dp's are never altered, so why do 2 copies of the 
points exist ?

Cheers
-- 
===============================================================
Philippe P. Pebay             |  pppebay at ca.sandia.gov
Sandia National Laboratories  |  Phone: +1 925 294 2024
PO Box 969, MS 9051           |  Cell : +1 925 784 3255
Livermore, CA 94550 U.S.A.    |  Fax  : +1 925 294 2595
            www.ca.sandia.gov/CRF/staff/pebay.html
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