How to make a HL2 ladder.

First, make a prop static set for the ladder's model.


Now spawn a func_usable_ladder. Make it about one unit from touching the ladder.





Now, see that white circle in the 2d view?





Drag the white circle up so that the bottom of the rectangle that follows the circle is as high as the topmost part the player has to go over.


Now, place an info_ladder_dismount like so:


Place some more at the bottom like this:


These tell the game where you can leave the ladder smoothly, without them you have to crouch-jump off.

There is a very easier way to do this...I may make a tutorial on it.

yea i did it another way than chip

The brush based version of ladder?

http://developer.valvesoftware.com/wiki/Working_Ladders

Neither way works on all games, but they both work in garrysmod.