If I'm making a door that only opens once (after setup or point capture), is there a reason to make it a func_door over func_movelinear? What's the difference for tf2, and is one more expensive than the other? For the moment, I'm making the doors out of brushes and not dynamic props
func_door is more or less a more specialized version of func_movelinear that's easier to set up for, well, doors. I don't know if one is somehow more or less expensive than the other but the difference is almost certainly trivial.
I figured out another significant difference, the nav_generate function treats func_movelinear as solid brushes, but allows bots to walk through func_doors if they've opened up
https://developer.valvesoftware.com/wiki/Func_movelinear "Unlike a func_door, it can be positioned anywhere along its axis of movement, making moving things much simpler in most cases while also using less memory." So yes, it is cheaper
