In toribash it looks like after a joint's state is toggled to contracting (or extending), a force or torque is applied along the joint in one direction; as you progress some frames, you see the connected bodyparts will move appropriately until that joint's LIMIT is reached.

For example, when you extend the knee joint, the knee locks eventually to stop your joint from overextending; if a joint is fractured, these limits are ignored and you see the leg keep moving past the limit in a gross looking way.

What I want to know is: is there ANY way at all to figure out how "extended" or "contracted" a given joint is?

What I want to do is have a function return a value from 0 to 1, with 0 meaning the joint is completely extended (like the starting position, jumping jack pose), and 1 meaning the joint is fully contracted (like when the force from the joint can't bring the two connected bodyparts any closer than they are).

Anyone have any ideas, did I overlook something really obvious?
Thanks