Resample Curve by N attribute

[philpappas]

hello,

i have a curve in 3d space with an organic shape and i want to resample it so it becomes jagged but maintaining its features. So i was thinking i should compare the tangent value of  each point with its next one and if the difference is big it means the curve is changing direction so i keep that point. If there is no big change in direction i remove points. But i have no idea how to implement this in Vop or Vex, i am new to Houdini. Any ideas?

[Sean Lewkiw]

Have you tried just using a facet SOP with "remove inline points" and playing with the "distance" parm?

[philpappas]

yes tried that, also tried the reifne sop, not exactly the effect i was going for, but it works.

I think it requires more local control, imagine you did this by hand, and you had to make this curve jagged while retaining its features, so to make it more like what a hardsurface panel would look like. the two methods mentioned produce the result in the image below

[konstantin magnus]

Hi philpappas,

to extract main features of your curve you could first measure its curvature with the new measure SOP or by calculating the dot product of your tangents (see attachment).

 

Afterwards a derivation of the curvature might be useful to only keep "break points" that are important to the visual appearance of your curve. I just would not know how to calculate this though.

curve_curvature.hiplc