Dynamic Rope using animation nodes but with fixed length

So I have seen this tutorial here https://youtu.be/BziV080OFHQ and this is basically what I need, a rope between 2 empties that I can move around the scene and it will update dynamically. This method however changes the length of the rope between the empties. Is there a way to have a fixed length? So if I move the empties closer the rope will sag further, and moving the empties farther away will pull the rope tighter.

Anyone know how this can be done?