Hello
I discretize the curve with points. If you say D is the minimum distance between curves. I put points on curve every D/5. I use various way to treat point Proximity, I didn’t find a best for all situation. I use Rtree, Dictionary and also a simple grid to fasten the point detection.
You’ll fin on discourse many Rtree examples.
You’ll find example of dictionary there
I will publish this component in a plugin
