DD4hep Meeting January 9th, 2025

Present:  A.Sailer, M.Frank, T.Madlehner

Apologies:

Link to minutes of previous meeting

Merged PRs

• PR1375:  Fix a few compiler warnings (Juan Miguel Carceller)
• PR1368:  Fix user analysis test (Andre)
• PR1367:  Allow for smartless configuration of volumes in Geant4 (Markus+Alvaro)
  
  Closed PRs:
• PR1381:  CI: add LCG_106 and enable EDM4hep for it. (Andre)
• PR1333:  Use edm4hep::labels::CellIDEncoding instead of "CellIDEncoding" (Juan Miguel Carceller)

Pending Problems

• 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);
  

   

        New issues:

• ISSUE1335: Uniform random picking of points on detector surfaces for noise studies
              This problem is linked to #1297 and #580.
• ISSUE1343:  want to get a parameter into ddsim SDAction at run time (Sarah Eno)
• ISSUE1369:  Create EDM4hep reader for DDG4 (Andre)
• ISSUE1373:  Add GeneratorInfo to EDM4hepReader (Andre)
• ISSUE1379:  Discussion: Evolution of edm4hep and dd4hep enhancement (Markus)
• ISSUE1382:  More useful crash message question (Sarah Eno)

        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:

• PR1380:  Restore compatibility with EDM4hep 0.10 (Juan Miguel Carceller)
• PR1378:  Use standard locations if the LD_LIBRARY_PATH or ROOTSYS are empty (Andriish)
• 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
• PR1376:  DD4hepSimulation: pass self to the steeringFile eval (Dimitry Kalinkin)
• PR1374:  Do not set or read the color flow for MCParticles from EDM4hep (Juan Miguel Carceller)
• ISSUE1369, ISSUE1373, 
  PR1371:  Read edm4hep (Andre)
• PR1370:  Feature celeritas integration (Sakib Rahman/EIC)

Closed issues and fixed problems

• ISSUE1360: Issue with Assembly volume and g4-copynumbers
• ISSUE1361: Controlling Geant4 smart voxelization from the detector constructor
               ====> CPU speed-up issue from Alvaro
• ISSUE1363: Rotated coordinate system on a measurement surface
• ISSUE1364: Potential Inclusion of Geant4 Kernel Initialization in Per-Event Timing bug (Alvaro)
• ISSUE1372: multiple actions within same subdetector question (Daniel Jeans)

Round Table

Andre:      The EDM4hep MC reader was generally accepted.
Markus:    Will attempt to investigate update of Geant4VolumeManager after discussion with John. (See attachment in the agenda).
Thomas:  NTR

AOB

----

Next meeting:   January 23th, 2025