Investigate error message: 'icdf null, snam::ICDF icdf.npy' during simg4ox command execution

[plexoos]

While running the following command:

simg4ox -g eic-opticks/tests/geom/raindrop.gdml -m eic-opticks/tests/run.mac

The following error message appears in the logs:

2026-04-02 17:11:57.602 ERROR [60] [QSim::UploadComponents@174]  icdf null, snam::ICDF icdf.npy

Despite this error, the command appears to complete successfully. It is unclear if the error message indicates an actual critical problem, or if it is a false positive/fake message.

[ggalgoczi]

Did you have scintillation properties in this geometry? If not that is the cause. Simphony complains that there is no scintillation defined so it can not load the icdf table to GPU.

Also in Simon's reply to your previous post: https://groups.io/g/opticks/message/515?p=%2C%2C%2C20%2C0%2C0%2C0%3A%3Acreated%2C%2CUploadComponents%2C20%2C2%2C0%2C104211135

[plexoos]

Ah yes — I had forgotten that I had asked about this before. In any case, it’s time to address it properly. At a minimum, this should be reported as a warning rather than an error if it does not affect the result, and if a geometry lacking scintillation properties is still considered valid. Would you have the capacity to investigate this?

[ggalgoczi]

After I am done with dd4hep integration, wavelength shifting and trapezoid implementation I can take a look.

[ggalgoczi]

@plexoos why did you close this and merged your PR? I commented there problem with the code. Your solution fails to import geometries that have reemission but not scintillation.