I finally figured out, after searching for a while, how to make my Curve extend the way I want it to. But now I have the problem that I do not know how long the curve is. The goal is to multiply the curve length from 0 to one. Where 0 means that the curve is not extended at all and 1 means that the curve is fully extended. But it doesn't seem to work somehow. Can someone help me to find out the curve length used by the trim curve node?
Attention: Spline Length does not bring my searched result! Then it really behaves as I want with the multiplication, but the splines extend completely differently, namely not as nicely together as they do when nothing is inserted in the Trim Curve Node.