Including the fonts used for the text under buttons, to sizes and dimensions of the cabin in general, to physical models of the levers and buttons. Do they ask for the CAD files from the manufacturer(I don't think they would accept?) or do they just take a million photographs from a lot of different angles and use lots of tape measure. For recreating fonts or shapes, taking a very very close and HD photo of the text and then tracing it on Adobe Illustrator could work, but making screens still sounds difficult.
If they are able to, they get access to a real train and take thousands of photos covering every inch of the train. If not, the companies could give technical documentation as part of the licensing agreement. They also have some dimensions online like on wikipedia. Community members could take photos and share it with dtg or if there are high quality YouTube videos or photos online of the interior, those could also be used as reference towards what it should look like such as the seating arrangement or how many doors there are, where the bathrooms are located, etc. It's definitely a combination of lots of things to make it as close to the real thing as possible
I think they may also use this device (looks like a white box I think it’s like a laser type camera or something) on a kinda tall tripod. this is astregon using it for their game “bus sim” you will see it at about 18 seconds in (I’m pretty sure bus sim 21 and TSW4 run on the same engine as I do find similar/same bugs )
Interesting machine. We had something similar in my previous workplace(Leica BLK360 I think it was). But this looks even more detailed.
I think they could use laser scanning or photogrammetry to get accurate dimensions and than model the final mesh on top of that. Otherwise, a skilled 3D artist should be able to scale things well enough so it doesn't look off (and make them fit) even without this kind of precise reference. My final guess is that they have drawings to get basic dimensions and then use photos to create the rest.
As for drawings, it probably depends on the TOC and how helpful they are willing to be, since generally interiors even for the "same" model of coach are bespoke for each customer, which provides or gets a copy of the plans (or in the case of DB does many of them in-house).
You can make a decent enough model of an interior with a few dozen interior photos and some educated guessing. For stuff like fonts there are plenty of sites that will identify them for you.
Though fonts have to be licensed. That's why on neraly every route some fonts (e.g. station signs) are wrong. But tbh, spending a ton of money on a certain font when at the same time you have acess to a font which looks similar is fine for me.
