"Points" is not recording some nodes.

[quantatanu]

Hi,

while working on the external muon ID of DUNE ND, I wrote the following algorithm to see if a track passes through a pair of readout strips in an RPC, it looks like this:

The detector: The RPC is placed just outside the KLOE magnet, first layer being Foam0, then XX copper Strips, then bakelite etc and the gas gap, after the gas gap, again bakelite etc and in the end Foam1 followed by 'Strip YY'. So the order is Faom0->StripXX-> ... -> gas gap -> ... -> StripYY -> Foam1

The algorithm: I first check if I have hits in the gas gap, if there are, then I scan that track using Points class and access the node names corresponding to those Points, I want to find the particular XX and YY strips in its path.

The issue: most of the time I find YY Strips as well as Foam1 but do not find any XX Strip in the track! That is so weird!
My thoughts and tests:

1. I thought, maybe the gap among points of the Points could be wide enough to miss a thin node (0.5 mm thick strips), so I started subdividing the gap between two points that are widely separated (~0.25 mm), I still don't find the XX strips!
2. So, I thought maybe, node names are saved corresponding to each point of the "Points". subdividing the gaps may not help because maybe node names corresponding to those mean points are not stored in the root file!
3. So, as a desperate test, I increased the dimensions of my components 10 times, 0.5 mm strips are now 0.5 cm, I still find majority of tracks have YY Strips but no XX Strips names when accessed through FindNode(x,y,z)->GetName() where (x,y,z) are coordinates of Points accessed using event->Trajectories[trackid].Points.at(ii).Position.X(), Y(), Z().

By the way, in the mac file I specified /edep/db/set/trajectoryBoundary charged:EMIRPC_lv_PV where EMIRPC_lv is the logical volume containing the whole RPC. I alo thought, maybe specifying each strip name would force Points to not miss any of the strips, so I did include edep/db/set/trajectoryBoundary charged:volEMIRPCBakelite_0_PV and all other (84 XX and 212 YY strips!).. which shouldn't be done I suppose because there will be thousands of components in some detectors, for example, straws in the STT volume, writing each node name down seems impractical. Can you please tell me what I am doing wrong, or maybe Points has limitations?

Thanks