Exporting triangles intersecing with fiber surface

[Mohit Sharma]

Hi,

I have the following two queries regarding fiber surfaces:

1. What does the EdgeParameterization field in the point data represent?

2. I see the TetIds field in the cell data, which I expect corresponds to the domain tetrahedron containing the fiber surface triangle. Is there an easy way to export the domain tetrahedra, triangles, edges, and points intersecting a particular fiber surface triangle?

Thanks,
Mohit Sharma

[Julien Tierny]

Hi Mohit,

thanks for your email!

> 1.
> What does the *EdgeParameterization* field in the point data represent?
This is the parameter "t" from the section 5 of "Fast and exact fiber surfaces for tetrahedral meshes" (see Fig 6 of that paper).

> 2.
> I see the *TetIds* field in the cell data, which I expect corresponds to

> the domain tetrahedron containing the fiber surface triangle. Is there an
> easy way to export the domain tetrahedra, triangles, edges, and points
> intersecting a particular fiber surface triangle?

The most efficient way would be to write some C++ code (for instance at the end of the ttkFiberSurface class) to retrieve these tets (and their faces) from TTK's triangulation data structure.
A less efficient but convenient way would be to use the ParaView filter "TTK Triangulation Request" from a pvpython script. There you can extract any simplex from its identifier, along with its faces, cofaces, etc. You'd just need to write a Python snippet that parses the list of tets from the fiber surface and feed that to the triangulation request module.

I hope this helps.

Thanks for letting me know if you need further information.

Have a great day!

Best,
--
Dr Julien Tierny
CNRS Researcher
Sorbonne Universite
https://julien-tierny.github.io/

On Tuesday, 24 February 2026 11:45:13 CET Mohit Sharma wrote:
>
> Hi,
>
> I have the following two queries regarding fiber surfaces:
>

> 1.
>
> What does the *EdgeParameterization* field in the point data represent?
> 2.
> I see the *TetIds* field in the cell data, which I expect corresponds to