Hey there,
I want to extrude this red contour lines on this violet surface in grasshopper.
I have done it on rhino but it is a very tiring and time-consuming process.
like
offset each curve one at a time on the surface. using an offsetnormal command.
There are really two ways (I can think of) that you can approach this.
The first one being, to move curve points along the surface normals at the specific locations and redrawing interpolated curves through these points. These curves can then be used with their corresponding initial curve to form a loft. The resulting surface will be doubly-curved.
The second method would be to average the sampled normals of each curve and use that average vector to extrude the curves. You’ll end up with a single curved extrusion, if I’m not mistaken.