Moving a TGeoVolume inside the geometry

ROOT
1

Suppose you have build a whole geometry, you have called gGeoManager->CloseGeometry() and you want to make a series of runs where you want to move a given TGeoVolume from run to run. Is it possible to call

TGEoVolume::RemoveNode()
TGeoVolume::AddNode()

to do that? Or is it too late because CloseGeometry() has been called? If it is not possible, is the only solution to delete the whole geometry and rebuild it entirely from run to run?
Thanks for your help

2

Hi,
Indeed, once the geometry closed it is too late to remove nodes. The RemoveNode() method is more intended for the geometry builder GUI.

But you can “misalign” an existing (physical) node. See:
ftp://root.cern.ch/root/doc/18Geometry.pdf page 340

Cheers,

3

I have tried your solution and it works perfectly. Many thanks.

4

Hi,

This link does not work anymore. Can you please provide a description how to perform this “misalignment”?

I need to remove a node from the existing geometry saved in a ROOT file.

Thank you,

Konstantin

5

I think I have found it:
https://root.cern.ch/root/htmldoc/guides/users-guide/Geometry.html#representing-misalignments-of-the-ideal-geometry