Do you mean unpowered rolling stock? Like freight cars? I'd imagine locomotives are more difficult because of the addition of an engine and traction physics, but the structure and artwork would be necessary for both so they're both challenging.
I don't think there's much difference between a railcar, DMU/EMU or Loco for game dev purposes. I mean, isn't the 142 a "railcar" or rather "railbus"? It'd more depend on the vehicle in question if anything (some are a lot more complex, esp with electronic screens and such)
Without access to Simugraph and how it handles different parameters, hard to say. Personally I would say a loco might be harder but then a modern DMU with hydraulic transmission and final drive might also be challenging.
A Rail Car is basically a locomotive with passenger bits in it. It has two cabs, same as most locos (at least in UK/Europe), it has engines, brakes, lights and such. There's really not much difference from a component perspective between a rail car and a loco - except - the rail car ALSO has all the passenger compartment in it too. So - making it in the game, usually the loco is easier because setting up all the seats, door animations, etc etc is a bit of a pain. There are going to be some locos more complex than the average rail car though, but on *average* railcar will be more time consuming. Matt.
Do you mean a coach / carriage? So in the UK at least a Rail Car is a single powered vehicle capable of hauling passengers on its own. If you mean simply a coach, such as a superliner or something then they will always be easier than a loco - the physics is very straight forward, audio is quite simple, the number of interactions is low because there is no cab, and the only extra wrinkle is all the seating setup but that's nothing compared to the stuff required to make a loco work. ART wise - a coach is often much closer, because a loco might not have the interior but does have the cab. That said, coach interiors often have lots of duplication as the seats are usually only a few types and then placed in the vehicle. The detailed interiors on coaches do significantly add to their dev time though. Ofcourse if its a driving trailer like a cab car then that's more like a loco + coach mix because of all the cab set up needed, though often simugraph and audio is still simpler than a full loco would be. Bottom line I guess is that it's very specific on the specific vehicles but hope that helps a little. Matt.
ah ok what fright car like cyclical hopper or bathtub gondola cars etc... actually could you copy the Simu graph freight car aspects from fright car that already made and just make new fright car to that car. https://churcher.crcml.org/circle/GovernmentHoppers.html https://www.pwrs.ca/archive/dyn.Mar_12_2007_Sultran_PWRS_Special_Run.php
