pub fn coplanar_overlap(subject: [Point3; 3], clip: [Point3; 3]) -> Vec<Point3> ⓘExpand description
The overlap of two coplanar triangles, as a 3D polygon.
subject and clip must be coplanar; the caller establishes that with
triangle_triangle_relation.
Returns the overlap polygon’s vertices in order, or an empty vector when the triangles share a plane but no area. An empty result is a normal answer, not a failure: coplanar faces that do not overlap are common and contribute nothing to a boolean.
A result with fewer than three vertices is returned empty. Such a polygon has no area – the triangles meet along an edge or at a point – and reporting it as an overlap would create degenerate faces downstream.
§Panics
When a coordinate is NaN or infinite. The signature has no error channel
and an empty result would claim “no shared area”, so a non-finite input is
a violated precondition; intersection_segments
refuses such a pair with a typed error before calling this.