Help Best practices for climbing up / down a rope?

[ShawnF]

The rope should be enough to make the character swing, no need for the extra hinge joint. Otherwise you'll get a rope that sags below the character, as it's impossible to make a group of distance constraints (or constraints of any kind, for that matter) converge perfectly.

I'd definitely be up for removing the hinge if you feel like it will be problematic in the long run, I mostly just had some trouble getting the system working without it. But at the moment I'm confused by the issue you describe. Isn't that actually the expected behavior? I'd think that the rope should be taut from the top until it touches the character, and then loose below that point. Or did you mean something else?  

In any case, I'll spend a little time trying this out and see what issues I run into. Hopefully it resolves my issue.

If you want to keep the hinge joint, you can get the length from any particle to the top of the rope by iterating trough rope elements towards the top and accumulating their length.

Thanks!