I've got a reasonably game together now, but I really can't figure out how to allow the player to jump. Either I'm completely confused and I'm stuck on something easy or I'm just doing it wrong, but nothing seems to work.

I'm currently using the movement system from workshop 23 (one of the tutorials) just to stuff around, I've added quite a few features which I'm happy with, but what I'm lacking most right now is jumping.

I tried searching around but surprisingly I haven't found any code or questions/answers related to it. I may have just searched improperly but I tried.

Any help is appreciated.