It seems that I have to build the items separately.
- Train body
- Bogie
- Wheel
- Pantograph
- Doors
- Seats (repeated items)
For the driving compartment, it is more complicated.
No, not true at all. You can build everything as one item to begin with, it makes everything a hell of a lot easier if you build everything in one file at once, because you can see whre bits fit.
The only time when you need to seperate each component is when you export the item from Sketchup/Max/Blender/Whatever, as then the program references these items and puts the reference where there are points, which are termed "attachment points." If you feel really clever and want to reduce the poly counts, you can break everything down into components, basically, a small section like part of a body, then use attachment points to "repeat" the object so you get a carriage or as you say, seats, doors and the like.
Most vehicles will only need to be exported as:
- Body
- Bogies (including wheels)
- Pantograph
- Cab (not driving compartment by the way, the proper term as far as I know of, is a "drivers cab") and other interiors you may wish to export, like a passenger view if you so wish to do so.
- Any meshes that are removed and repeated to increase performance or have animation.
Does this help?
As for exporting, there is good news, you DO NOT need a texture to export an object, but it DOES need mapping coordiates, so you may have to add some sort of UVW modifier, you also need to name/use a texture with (name_of_material).m.notex for anything to export properly.
