Module self_intersection 

NURBS surface self-intersection detection.

Detects regions where a single NURBS surface folds back on itself, producing S(u1,v1) = S(u2,v2) with (u1,v1) ≠ (u2,v2).

Algorithm

1. Sample the surface on a grid, build triangles with (u,v) parameter ranges
2. Build a BVH over triangle AABBs
3. Query overlapping pairs, filter out adjacent triangles
4. For non-adjacent close pairs: Newton-refine with constraint (u1,v1) ≠ (u2,v2), S(u1,v1) = S(u2,v2)
5. March along self-intersection curves

Structs

SelfIntersectionCurve

A self-intersection curve on a NURBS surface.

Functions

detect_self_intersection

Detect self-intersections on a NURBS surface.