[Mean Height] vs [Max Height]

[Mael]

Elaborate?

AFAIK, crouching currently occurs instantly. Meaning, the moment you press the button, your head instantly drops to it's crouch location. The moment you release the button, your head instantly returns to it's standing location. The transition occurs instantly, even though the camera appears to droop. This is one of a few inconsistencies between what the player sees and what is actually occurring. Another example is when you are running, the camera remains steady while the head bobs slightly.

If the head drooped the way the camera did, there would be a slight delay between the moment you press the button and the moment you could enter a tunnel too short to stand in. Raise the floor of that tunnel slightly enough so players can still crouch through it but enough to prevent players from walking in through the entrance without jumping and you have a one way "door".

To put it as simply as I can, you can only jump if you are not crouching. Jumping takes time but crouching does not. If it took time to crouch, you could raise the floor of the tunnel enough so the player must jump and crouch in the air to get in. But the crouch delay would be too long; you'd hit the ceiling and bounce back down before you could crouch low enough to enter.

I did make a simple map to try to make it work and it almost does. It blocks about 90% of all attempts but every once in a while you get through.