the interactive cloth is a great tool and i was wondering if its possible to create a infinitely long piece of cloth (even tough that would be insanely expensive) simply by adding more verticles to it at run time or if the mesh used by the cloth needs to be predefined ,also would it is possible for the mesh to remain closed and to have internal air pressure
Highly doubt that's possible...
However, a lil thing you could do, is make a "model" of a plan that kinda thins out, to give it an illusion of being really long, then just have it move with the player... I'd assume this could work, and wouldn't be nearly as expensive...
Just a suggestion though! =). Good question though.