Function closed_at_poles 

pub fn closed_at_poles(
    model: &mut Model,
    surface: SurfaceId,
    edges: &[Shape],
    tol: Tolerances,
) -> OgeomResult<Vec<Shape>>

A wire’s edge uses with the chart closed where the surface collapses.

A face whose boundary passes through a pole or an apex meets it in space at one vertex, but in the chart the use arriving there and the use leaving it sit apart along the row (or column) that collapses to that point: a sphere bounded by its seam walked both ways arrives at the north pole on one side of the chart and leaves it on the other. An exchange file has no edge for that stretch, and without one the boundary does not close in the chart. Between consecutive uses that share a vertex and whose images sit apart on a stretch the surface maps to that one point, a degenerate edge is put in, its pcurve the straight run across. A wire whose images break anywhere else (an image a period off its neighbours, which the mesher folds back) has no run to trust, and comes back as it is, as does one with a use that has no image on surface.

Errors

OgeomError::Dangling if the surface, an edge or a pcurve is not in this model.