Expansion directive isn't visible in the GeoViewer

Hello, when transforming bodies with the geometry directives, I can clearly see them moving or rotating when using $Start_translat or $Start_transform. However, when I am trying to use an expansion geometry directive ($Start_expansion), it has no effect on the bodies in the GeoViewer visualiser. Why is this? Is there something I am missing? Is this working as intended? Thanks for your help.

Dear Stwalker,

welcome on the FLUKA Forum!

I added a $start_expansion to the example available in the FLUKA directory. Using Flair 3.0-1, the dimension scaling was visible in the Geoviewer.

If you can share an input file, where it is not working for you, we could take a look.

@stwalker thank you for reporting. Indeed it is not working, we will fix in the next respin. Most probably is due to the normalisation of the transformation matrix to fix numerical precision problems when dealing with small angles.
As a temporary solution you can use expressions to the coefficients which can help you to fine tune the expansion more accurately. For example only in the dimensions and not in the position.

SPH x: 10 y: 0 z: 0 R: =5*inch

@stwalker correction to what I’ve set, on my test example the Start_expansion is working. As @horvathd mentioned please send us your input to check.