How can you make a rope like this without joints?

I am trying to make a rope like this. I have tried to raycast from the ball tracing points backwards as I move and draw it with a line but it is really complicated once you start moving back especially. Do anybody have a better idea to make this happen?160451-rope-2.gif

I’m also looking for the same answer. Joints are prone to falling apart, even when breakforce and breaktorque is infinite. Even when you follow all the steps Unity recommends to increase stability. In my game I don’t need breaking at all. What I need is a rope that bands and twists and interacts with other ropes and colliders but without the weakness joints. Obi rope (a particle based rope in asset store) has a lot of limitations (unintuitive, poor documentation, hard to learn it, hard to have it interact with colliders etc).
@Bunny83 Any idea?

Well, the exact purpose is not clear. Ropes may have different definitions and purposes. In the example shown it seems there are not external forces applied and the “rope” doesn’t have a limited length but acts like an idealized rubber band. If the desired mechanic is to be able to wrap the rubber band around those “pegs”, you can do this analytically. Though it’s certainly quite tricky.

I would logically split the total path into straight sections and wrap-around-arcs. The arcs would have a positive angle that is relative to the starting tangent. As soon as that angle gets “smaller” than 0, the arc would be removed and you go back the chain one step.

Detecting the attach points could also be done analytically with planes and side checks and the changes between two frames

What may be slightly relevant thematically is this One More Line question. (For some reason I just had to think about this 3b1b video about the windmill puzzle as well ^^).

So it’s mainly a matter of data organisation. Of course we talk about a pure 2d scenario. In 3d things get exponentially more complex. So in 2d technically we only need one kind of anchor points: a circle. A plain edge could be represented by two circle anchors with radius 0 at the two ends of the edge. At a 0 radius circle the line would simply pivot around, still only in one direction, depending on where it was attached (left or right side, so it rotates clockwise or counterclockwise).