@whit, I came to the conclusion that doing a flexible SNSPD readout with what's in the DD4HEP is not feasible - realistically, it's not within our abilities to densely cover and read out a whole chip worth of individual ~10um pixels. I can somewhat emulate a ganged pixel readout by doing a MultiSegmentation of nested CartesianGrids (once I figure how to do that), but even that lacks some features. I will need to add a new Segmentation derived class to accommodate the SNSPD needs.
How do you want me to organize the file and folder structure. I don't feel that this code should go into GenericDetectors folder.