So I've decided that rather than scrap the grapple idea, I'm going to instead scrap a spatial dimension :)
I keep thinking about Little Big Planet and how cool a 2D game with 3D graphics can be. The recent indie game where you play the knight who keeps dying is another example. Forget it's name.
So I'll need to yank out the physics system and replace it with a 2D version. I have a 2D GJK lying around somewhere from when I was investigating the algorithm last year so should be easy enough.
I can easily put back into my level editor support for 2D collision shapes again then that side is sorted.
It will be nice to tackle this without using Box2D this time. This isn't planned as a heavy physics game and character controllers a bitch to get right in a real physics context.
Now I've got my head around the maths for a spring force, should be possible to deal with the physics myself, and I know I can get a grapple rope working great in 2D so full steam ahead.
This is the plan anyway. Taking a dimension out of the physics makes a lot of things simpler, including on the content pipeline side which has traditionally been my problem.
Screenshots next time. Promise.