[vtkusers] TensorGlyphs

[Jose Paulo Moitinho de Almeida]

Hello 

I have collected the modifications that I made to vtkTensorGlyphs which are 
available at http://www.civil.ist.utl.pt/~moitinho/vtk/vtkTensorGlyph/

There you may download a patch or the modified vtkTensorGlyphs.[ch].

These modifications include:

- adding three new boolean variables to the class: ThreeGlyphs, Symmetric and 
ColorEigen. The first two define wether we want to draw just one (ThreeGlyphs 
is false and Symmetric is false), two (false, true), three (true, false) or 
six glyphs (true, true). The other variable (ColorEigen) defines if each 
glyph is colored according to the corresponding eigenvalue.

- adding a new float: Length, which is needed to draw (preserving the 
orientation) the symmetric of a glyph.

A new variable numDirs (1,2,3 or 6) controls the cycle of drawing. The 
greatest change is in the drawing itself, as the 
translations/scalings/rotations have to be performed according to the type of 
representation required.

Looking at an ediff should be enough to have an idea of what I did.

In the same directory I have also included the an example in python 
(example.py), which requires a vtk data file (tensor.vtk), as well as 
modified TenEllip.tcl which is now OrientedTenArrows.tcl, where those that 
understand the Boussinesq solution will appreciate the information about the 
sign of the radial and tangential stresses.

If these changes are acceptable I am hereby giving permision to incorporate 
them into vtk.


Regards

Ze Paulo