Discussion Item: Improving CopyNumberLevel/positionIndex handling in GeoModelXml
When revising some aspects of the ITk geometry in GeoModelXml, it has proved quite difficult to understand the CNL_ indices that get generated, and thus how to update the logic for assigning/combining them to produce positionindices than can be used for generating Identifiers.
One thought that came up that might improve this was if it was made possible to assign a specific CNL_N to a structure, as this would help knowing which ones should be used where, and also allow them to be consistent when working on both "full" and "partial" versions of the geometry (e.g. when debugging by running just a single barrel layer geometry - at the moment this would completely change the CNL meanings compared to running the full geometry).
My thoughts were along the lines that:
-
It should be possible to specify the
NinCNL_Nin the same way one specifieszeroidto determine whether things get reset to zero -
We should then keep track of which
Nhave already been assigned, and anyCNLfor structures which don't specify a value should start fromN+1
I think this might be a start towards making this part of the geometry development a bit more straightforward. I just wanted to see what people think about this before I start actually working out how this could be achieved and trying to implement it.