Changing planes, or rotating planes to presumes a varies slope

Hi Experts

I am trying to learn GH for another concept.
i am trying to super elevate a bridge deck so i can assign super elevation slope range from 0 to 3.5% from start to middle of the given curve (7.9 KB) Untitled.3dm (28.8 KB) and then reverse back from mid of curve to end for 3.5 to 0%.
just needed the concept to get it going.
A bit tricky but not impossible.

Best Regards and have a great day.

Not sure this is what you want, anyway check this… (12.4 KB)

Yes. its similar and Thanks lot.

More obvious when display something like this… (13.4 KB)

Well in real life we use a Gauss distortion instead of some classic one (Sin for instance). This yields correct/smooth “transition ramps” (but in big bridges this gain is rather marginal). See attached as a concept demo and if required include the Math used in some GH solution vla native components. (121.9 KB)