Using alignment conditions with DD4hep
@gcorti @adavis @kreps @bcouturi @sponce @tlatham
This issue depends on the solution coming out from the discussion in #15 on how to properly access the dd4hep/detdesc conditions.
Description
Gaussino, as of today, is equipped with a configuration that allows for having just one run (G4Run) during the execution of the main simulation algorithm. All the geometry, sensitive detectors, and magnetic fields are constructed before the run at the initialize time. We do not expect the geometry to change within the run. Therefore, all the alignment conditions can be read and integrated when the geometry is constructed.
For dd4hep, this is done in DD4hepCnvSvc
. We load an XML file and convert the geometry with Geant4Converter
from DD4Hep/DDG4
. As I could not find any alignment conditions support in Geant4Converter
, below you will find a few possible options that I managed to come up with.
Available options
- Change the code in
Geant4Converter
such that it handles alignment conditions and transmits the information correctly during the conversion. No additional code is needed in Gaussino, just passing the conditions in the function's signature. - Implement our own code, that would update the geometry already created by
Geant4Converter
. This could be handled in a similar way as it was done in GaussGeo (detdesc case)
Any comments or other ideas would be very much appreciated!