DD4hep Meeting February 20th, 2025

Present: A.Sailer, M.Frank, Peter McKneown

Apologies: A.Tolosa Delgado, T.Madlehner

Link to minutes of previous meeting

Merged PRs

PR1403: Have more consistent test naming
---> Cast out everything using Geant4 in tests : $> ctest -E _sim_
PR1404: Remove compiler warnings for MacOS
.... Checked once again compile logs when creating a PR
PR1405: Enable random seed printout to debug flaky BoxOfStraws example
---> New error: apparently G4 steps can pass sensitive volume boundaries.
Causes trouble, because we use the pre-step touchable to determine
the sensitive volume.

ISSUE1199: Persist hepmc vertex status code into output
==> Should we eliminate Geant4EventReaderHepMC
==> Decision: Geant4EventReaderHepMC will be removed
ISSUE1285: Memory Consumption of Sensitive Detectors
==> Should be handled as illustrated in PR1288. Intrinsic problem of the Geant4VolumeManager;
ISSUE1296: DetectorImp::endDocument() called twice for some geometries?
==> Unsure if it is a problem wrongly configuring multiple xml inputs.
ISSUE1297: Possible to dump all available readout elements?
==> Possibly a copy of unsolved ISSUE580 from Valentin about enumerating all sensitive cells.
ISSUE1319: Problem with regexSensitiveDetector and volume IDs
==> Interesting use case for reg-ex sensitive detectors
having a VolumeMgr equivalent.
ISSUE1320: Replacing a Handle<Segmentation> which contains a MultiSegmentation with the underlying Segmentation
===> Unclear what he really means. Questions after re-reading, calls like:
```
Handle<SomeSegmentation> seg = multisegmentation->subSegmentation(cellID);
or
Segmentation* seg = multisegmentation->subSegmentation(cellID);
```
ISSUE1335: Uniform random picking of points on detector surfaces for noise studies
This problem is linked to #1297 and #580.
ISSUE1373: Add GeneratorInfo to EDM4hepReader (Andre)
PR1371: Read edm4hep (Andre)
ISSUE1399: ddsim: Vertices of tau and its decay product not matching the information in the input HEPMC file
---> Apparently Geant4 problem. Andre has submitted a ticket.

Pending PRs:(no changes since last meeting):

PR1240: Add multithreading support to ddsim
PR1304: SurfaceManager: lazily construct surface maps on demand (Leonhard Reichenbach)
PR1314: Cylinder segment surface (Armin Ilg)

New Pending PRs:

PR1370: Feature celeritas integration (Sakib Rahman/EIC)
PR1377: Use canonical variables for the installation locations of libraries and binaries (Andriish)
==> Idea to have an additional DD4HEP_PLUGIN_PATH and remove dd4hep plugins fdrom the LD_LIBRARY_PATH

ISSUE1379: Discussion: Evolution of edm4hep and dd4hep
---> Not too much response.
ISSUE1392: DD4hep installation fails if Intel compiler is used for compilation
==> Should we support icc ?
ISSUE1393: DD4hep installation fails if Intel compiler is used for compilation
---> Declined, until Intel compiler is supported by SFT.
ISSUE1400: Question about (Primary) Vertex mismatch - wrong smearing?
---> Closed by Andre
ISSUE1402: CI was failing to install cvmfs, caches removed, works again
---> Closed as completed by Andre

Andre:       NTR
Markus:    NTR
Peter:        NTR

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Next meeting: March 6th, 2025