Already available:
Var 62 / other_veh_xyz_offset: Give positional offset from current vehicle to n-th following vehicle.
This can be used to provide diffeent orientations for a vehicle for all combinations of x, y, and z differences.

New OTTD feature: "distribute sprite over multiple articulated parts"
* Articulated part gives sprite and says "span this sprite over this and the next N articulated parts".
* OTTD takes the sprite, and draws it at the xyz-center between 1st and Nth articulated part.
* Drawing is done by cutting the sprite horizontally/vertically into multiple parts and putting them into the bounding boxes of the single articulated vehicles.
* The latter prevents most clipping with depot, tunnel, foundations, bridges, ...