My head is gonna explode.

I think I may venture to say that I understand vaguely what is happening. I am probably biting off more than I can chew: I'm not at University yet, I'm one of the 6 people in my school who even know what a vector product

*is*(having been one of the few who studied Further Maths).

Taylor expansions? I've never used them but I vaguely know what it is. Luckily I can avoid them for now. Even Euler is at the brink of what I have been taught.

But I may well have a go at this system. I will need some help. Now you have shown me a superior system, I would prefer to use it instead. Here is what I understand.

-The motion is handled by Verlet integrator. It calculates the future position of a point using the current position and the position

*before that*.

-The constraints I would need would be a distance constraint (as mentioned). The constraint is simplya mathematical expression to satisfy (effectively these are loci). If the constraints are satisfied the Verlet integration does the rest (thats the magic of it). Constraints are satisfied by (what looks to me cheating): changing the values so they are what you want (if they are

*not*what you want of course)

-The constraints are solved by interation by some mathematical magic. An atempt must be made to satisfy

*all*the constraints.

-The square root approximation is not essential so I can leave it out for now.

So as far as a rope simulator is concerned:

-Each vertex has a "stick" constraint to the next based on the original length. The Verlet integrator does the rest. I will have to investigate how you solve all those constraints together a little more closely.

To be honest, this system strikes me as being a very fast and clever IK system that is adapted to strings, cloth and rag-doll physics. Coding this may be worthwile as it could be used for loads of things.

If this ever gets as far as collisions, I suppose I could use my brute force method (which I may be able to do) or use Solid. If I use Solid I'll need some serious help (but thats a while yet).

Anyway...thanks eeshlo! (Maybe you could even help me out a little )

Koba