Function point_inside

pub fn point_inside(
    point: Point3,
    solid: &TriMesh,
    tolerance: Tolerance,
) -> Option<bool>

Whether point lies strictly inside the closed mesh solid.

Uses the generalized winding number rather than ray parity. Parity is unreliable exactly where building geometry lives: axis-aligned boxes put rays along faces and through shared edges, and every tie-break there is a guess. Winding accumulates oriented solid angle, so it degrades smoothly instead of flipping.

A point ON the boundary has winding near 1/2 and is deliberately NOT inside: two slabs sharing a face are in contact, not overlapping. That single decision is what keeps every abutting wall out of a clash report.