I definitly thought i posted a possible solution to this, but it must've encountered an error.
It might be possible, but with a huge amount of entities.
what you will need is a func_train
trigger multiples
trigger changetargets
multi_managers
path_corner
and loads of patience.
Try this out:
Make a big room with a func_train
place 12 or so trigger multiples in the room (64 unit cubes)
inside each trigger multiple place a trigger changetarget and a path_corner
(im not sure how trigger changetargets work, so this is just a hypothesis on my part)
have the trigger_multiple change the target of the func_train to the path_corner nearest you VIA a trigger change target
If you didnt get that.
Basically, if you walk to one corner of the room, the func_train will go to the path corner nearest you, and if you move, the trigger_changetarget will select the closest path_corner to you based on which trigger _multiple you select.
The ONLY problem i can see with this, is making the train not solid, and having it travel through walls around corners.
Try it out