Intersection points over surface from which perpendicular lines start

Hello everybody,

I received a GH file in which I have an hyperbolic surface (like a 3D egg shape)
On top of it, a pattern with 2D lines has been projected over the surface: that’s how I get a grid with an curved shape. From it, I got all the intersection point thanks to “MultipleCurves” (MCX)

What I would like to found out:
I would like to generate lines from those intersection points and they also need to be perpendicular to the surface underneath.

If someone has an idea, it would be very nice to know how to do it :slight_smile:
All my gratitude for your help!

Best reagards,

Hi @karimammor,

Welcome to the forums!

Simply use Surface Closest Point (SrfCP) to find a UV Point (uvP) for each of your points. Then evaluate your surface with Evaluate Surface (EvalSrf) at each UV Point, in order to find its corresponding normal. Lastly, draw a Line SDL (Line) from each point in the direction of the its designated normal and a desired length.

Please read How to ask effective questions to ask your questions more effectively next time!

Thank you P1r4t3b0y for your answer and the precious advice. I will read it carefully. Next time I’ll post more efficient and clear questions. The combinaison you gave is life saving! It could also work perfectly for other projects! Thanks again!