[vtkusers] vtkTensorGlyph | traversing all instanced glyphs

[jelle]

Hi,

I'm writing an exporter from vtk to a software renderer.
Right now, I'm traversing through the cells of the vtkTensorGlyph instance.
Which if not the best approach for sure.

Much rather I'd loop through the instances of the glyph that vtkTensorGlyph
produces. Also, rather than coloring per-face, I'd like to export the
vtkTensorGlyph instances colored on a per-object basis. 

My question is how I can traverse through the instances vtkTensorGlyph
generates, as well as finding its corresponding color in the vtkLookupTable.
Regarding vtkLookupTable, I haven't understood the GetTableValue method.

The method takes a vtkIdType as an argument, which is what puzzles me.
What does this vtkIdType correspond to? 
Perhaps the index of the cell its coloring? 

Many thanks in advance,

-jelle