@ylegall getting isolines as curves to move oriented quads along is next level stuff. i wouldn't even know where to start.

@ylegall thank you. what you do once you have the points was clear to me but how do you get the points?

@lritter @ylegall I assume it's like blender's "distribute points on faces". you just delete the ones that aren't near the isolines and the ones that are too close to each other?

@aeva @ylegall you can snap them with a distance field but how do they move? you would have to take the gradient and pick a tangent which is easy on a 2-manifold; yet you have two possible directions: cw/ccw

@lritter @aeva @ylegall
In a previous comment, the algorithm for building the isolines is described. I‘m guessing that the points of a line are then converted to curve primitives and evenly resampled using Houdinis „resample“ node. Houdini easily allows you to assign a value „u“ along a curve ranging from 0 (start) to 1 (end). This value can be used to look up the global xyz-position for a point at „u“ along the curve. Incrementing „u“ for every point moves it along the curve.

@jungkopf @lritter @aeva @ylegall yeah my guess too - the isolines don't change, so the isolines could be approximated by b-splines on the manifold, then animating is easy (since you know the arclength for the animation, which would be hard/impossible(?) to parametrically describe)