pub fn feature_edges(mesh: &Mesh, threshold_deg: f32) -> Vec<[V3; 2]>Expand description
The edges to draw for Eagle’s “Show Edges”: the segments where the
faces on either side meet at more than threshold_deg degrees, plus
the open edges with a face on one side only. Edges inside a flat area
(the diagonals of a triangulated quad) are left out.